Culturable bacterial communities associated to Brazilian Oscarella species (Porifera: Homoscleromorpha) and their antagonistic interactions.

PubMed

Laport, Marinella Silva; Bauwens, Mathieu; de Oliveira Nunes, Suzanne; Willenz, Philippe; George, Isabelle; Muricy, Guilherme

2017-04-01

Sponges offer an excellent model to investigate invertebrate-microorganism interactions. Furthermore, bacteria associated with marine sponges represent a rich source of bioactive metabolites. The aim of this study was to characterize the bacteria inhabiting a genus of sponges, Oscarella, and their potentiality for antimicrobial production. Bacterial isolates were recovered from different Oscarella specimens, among which 337 were phylogenetically identified. The culturable community was dominated by Proteobacteria and Firmicutes, and Vibrio was the most frequently isolated genus, followed by Shewanella. When tested for antimicrobial production, bacteria of the 12 genera isolated were capable of producing antimicrobial substances. The majority of strains were involved in antagonistic interactions and inhibitory activities were also observed against bacteria of medical importance. It was more pronounced in some isolated genera (Acinetobacter, Bacillus, Photobacterium, Shewanella and Vibrio). These findings suggest that chemical antagonism could play a significant role in shaping bacterial communities within Oscarella, a genus classified as low-microbial abundance sponge. Moreover, the identified strains may contribute to the search for new sources of antimicrobial substances, an important strategy for developing therapies to treat infections caused by multidrug-resistant bacteria. This study was the first to investigate the diversity and antagonistic activity of bacteria isolated from Oscarella spp. It highlights the biotechnological potential of sponge-associated bacteria.

Taxonomic composition and physiological and biochemical properties of bacteria in the digestive tracts of earthworms

NASA Astrophysics Data System (ADS)

Byzov, B. A.; Tikhonov, V. V.; Nechitailo, T. Yu.; Demin, V. V.; Zvyagintsev, D. G.

2015-03-01

Several hundred bacterial strains belonging to different taxa were isolated and identified from the digestive tracts of soil and compost earthworms. Some physiological and biochemical properties of the bacteria were characterized. The majority of intestinal bacteria in the earthworms were found to be facultative anaerobes. The intestinal isolates as compared to the soil ones had elevated activity of proteases and dehydrogenases. In addition, bacteria associated with earthworms' intestines are capable of growth on humic acids as a sole carbon source. Humic acid stimulated the growth of the intestinal bacteria to a greater extent than those of the soil ones. In the digestive tracts, polyphenol oxidase activity was found. Along with the data on the taxonomic separation of the intestinal bacteria, the features described testified to the presence of a group of bacteria in the earthworms intestines that is functionally characteristic and is different from the soil bacteria.

Bacteria Responsible for Mucilage-Layer Decomposition in Kona Coffee Cherries1

PubMed Central

Frank, Hilmer A.; Lum, Norma A.; Cruz, Amy S. Dela

1965-01-01

The predominant microbial flora present during decomposition of the mucilage layer of Kona coffee cherries were gram-negative bacteria which fermented lactose rapidly. Cultures isolated from coffee cherries under-going fermentation included species of Erwinia, Paracolobactrum, and Escherichia. Unblemished cherry surfaces and coffee plantation soil also had a microflora containing a high proportion of bacteria belonging to these three genera. Of 168 isolates tested, the 44 strains capable of demucilaging depulped coffee cherries were all members of Erwinia dissolvens. Supernatant growth medium liquids, after removal of E. dissolvens cells, actively decomposed the mucilage layer of depulped cherries. PMID:14325879

Isolation and characterization of marine bacteria capable of utilizing phthalate.

PubMed

Iwaki, Hiroaki; Nishimura, Ayaka; Hasegawa, Yoshie

2012-03-01

Eleven phthalate-degrading bacterial strains were isolated from seawater collected off the coast of Japan. The isolates were found to be most closely related to the marine bacterial genera Alteromonas, Citreicella, Marinomonas, Marinovum, Pelagibaca, Rhodovulum, Sulfitobacter, Thalassobius, Thalassococcus, Thalassospira, and Tropicibacter. For the first time, members of these genera were shown to be capable of growth on phthalate. The plate assay for visual detection of phthalate dioxygenase activity and PCR detection of a possible gene encoding 4,5-dihydroxyphthalate decarboxylase indicated that phthalate is degraded via 4,5-dihydroxyphthalate to protocatechuate in all the isolates.

[Characteristics of natural strains of naphthalene-utilizing bacteria of the genus Pseudomonas].

PubMed

Levchuk, A A; Vasilenko, S L; Bulyga, I M; Titok, M A; Thomas, K M

2005-01-01

Sixty-three strains of bacteria capable of utilizing naphthalene as the sole source of carbon and energy were isolated from 137 samples of soil taken in different sites in Belarus. All isolated bacteria contained extrachromosomal genetic elements of 45 to 150 kb in length. It was found that bacteria of 31 strains contained the IncP-9 incompatibility group plasmids, bacteria of one strain carried a plasmid containing replicons IncP-9 and IncP-7, and bacteria of 31 strains contained unidentified plasmids. Primary identification showed that the hosts of plasmids of naphthalene biodegradation are fluorescent bacteria of the genus Pseudomonas (P. putida and P. aeruginosa; a total of 47 strains) and unidentified nonfluorescent microorganisms (a total of 16 strains). In addition to the ability to utilize naphthalene, some strains exhibited the ability to stimulate the growth and development of the root system of Secale cereale.

Biosynthesis of silver nanoparticles by Pseudomonas spp. isolated from effluent of an electroplating industry.

PubMed

Punjabi, Kapil; Yedurkar, Snehal; Doshi, Sejal; Deshapnde, Sunita; Vaidya, Shashikant

2017-08-01

The aim of this study was to isolate and screen bacteria from soil and effluent of electroplating industries for the synthesis of silver nanoparticles and characterize the potential isolate. Soil and effluent of electroplating industries from Mumbai were screened for bacteria capable of synthesizing silver nanoparticles. From two soils and eight effluent samples 20 bacterial isolates were obtained, of these, one was found to synthesize silver nanoparticles. Synthesis of silver nanoparticle by bacteria was confirmed by undertaking characterization studies of nanoparticles that involved spectroscopy and electron microscopic techniques. The potential bacteria was found to be Gram-negative short rods with its biochemical test indicating Pseudomonas spp . Molecular characterization of the isolate by 16S r DNA sequencing was carried out which confirmed its relation to Pseudomonas hibiscicola ATCC 19867. Stable nanoparticles synthesized were 50 nm in size and variable shapes as seen in SEM micrographs. The XRD and FTIR confirmed the crystalline structure of nanoparticles and presence of biomolecules mainly proteins as agents for reduction and capping of nanoparticles. The study demonstrates synthesis of nanoparticles by bacteria from effluent of electroplating industry. This can be used for large scale synthesis of nanoparticles by cost effective and environmentally benign mode of synthesis.

Evaluation of the plant-growth-promoting abilities of endophytic bacteria from the psammophyte Ammodendron bifolium.

PubMed

Zhu, Yanlei; She, Xiaoping

2018-04-01

The objective of this study was to assess the plant-growth-promoting abilities of 45 endophytic bacterial isolates from Ammodendron bifolium through physiological characteristics detection and endophytic bacteria-plant interaction. Each of these isolates exhibited 1 or more plant-growth-promoting traits, but only 11 isolates belonging to the genera Bacillus, Staphylococcus, and Kocuria were capable of promoting seed germination and radicle growth. These results together with the results of the correlation analysis revealed that the completion of seed germination may not be due to IAA production, phosphate solubilization, pellicle formation, and ACC deaminase, protease and lipase production by endophytic bacteria, but may be closely related to amylase and cellulase production. Further, endophytic bacterial isolates with plant-growth-promoting traits may also provide beneficial effects to host plants at different growth stages. Thus, these results are of value for understanding the ecological roles of endophytic bacteria in host plant habitats and can serve as a foundation for further studies of their potential in plant regeneration.

Degradation of euptox A by tannase-producing rumen bacteria from migratory goats.

PubMed

Sharma, D; Mal, G; Kannan, A; Bhar, R; Sharma, R; Singh, B

2017-11-01

The gut microbiota capable of degrading plant biomass and antinutritional phytometabolites are of immense importance. This study reports isolation and characterization of tannase-producing rumen bacteria that could also degrade euptox A (9-oxo-10,11-dehydroageraphorone) present in Eupatorium adenophorum (Spreng). Migratory Gaddi goats were selected as source of inoculums for isolating rumen bacteria with ability to produce tannase which catalyses degradation of hydrolysable tannins (HTs). Three rumen bacterial isolates producing tannase were studied, and identified as Klebsiella variicola strain PLP G-17 LC, K. variicola strain PLP S-18 and Klebsiella pneumoniae strain PLP G-17 SC. The isolates exhibited optimal tannase activity at 40°C, and pH 6·0. The bacteria could also degrade euptox A, a potent hepatotoxin in E. adenophorum Spreng, a widely distributed noxious weed. The rumen bacteria could degrade antinutritional HTs and euptox A. Culture-independent metagenomic interventions are envisioned to completely decipher the rumen microbial ecology and exploit its genetic and metabolic potential. The bacteria producing tannase which catalyses degradation of HTs, and concurrently degrading euptox A, may have potential as microbial feed additives to increase utilization of plant biomass containing antinutritional phytometabolites. © 2017 The Society for Applied Microbiology.

[Screening and identification of a bacterium capable of converting agar to neoagaro oligosaccharides].

PubMed

Han, Junping; Huang, Yayan; Ye, Jing; Xiao, Meitian

2015-09-04

To screen and identify a bacterium capable of converting agar to neoagaro oligosaccharides. We took samples of porphyra haitanensis and nearby seawater, and then used the medium containing 1 per thousand agar to enrich the target bacteria. The target isolates were obtained by dilution-plate method, of which crude enzymes were further obtained by liquid culture. We adopted DNS method to determine the target bacteria which can convert agar to neoagaro oligosaccharides. The phylogenetics was identified by analyzing 16S rDNA sequence and combining the strain's morphological and bacterial colonial physiological biochemical characteristics. We isolated a gram-negative bacterial strain HJPHYXJ-1 capable of transforming agar to neoagaro oligosaccharides. Basic Local Alignment Search Tool (BLAST) search of HJPHYXJ-1's 16S rDNA sequence on GenBank suggested that the similarity between this strain and Vibrio natriegens reached 99% . In addition, the morphological and physiological biochemical characteristics of HJPHYXJ-1 also showed highly similarity to Vibrio natriegens. So we identified HJPHYXJ-1 as Vibrio natriegens. The results of HPLC suggested that the metabolite of enzymatic degradation was neoagaro oligosaccharides. HJPHYXJ-1 or the new isolate of Vibrio natriegens was capable of converting agar to neoagaro oligosaccharides.

Isolation of a human intestinal anaerobe, Bifidobacterium sp. strain SEN, capable of hydrolyzing sennosides to sennidins.

PubMed Central

Akao, T; Che, Q M; Kobashi, K; Yang, L; Hattori, M; Namba, T

1994-01-01

A strictly anaerobic bacterium capable of metabolizing sennosides was isolated from human feces and identified as Bifidobacterium sp., named strain SEN. The bacterium hydrolyzed sennosides A and B to sennidins A and B via sennidin A and B 8-monoglucosides, respectively. Among nine species of Bifidobacterium having beta-glucosidase activity, only Bifidobacterium dentium and B. adolescentis metabolized sennoside B to sennidin B, suggesting that the sennoside-metabolizing bacteria produce a novel type of beta-glucosidase capable of hydrolyzing sennosides to sennidins. PMID:8161172

Efficacy of indigenous soil microbes in arsenic mitigation from contaminated alluvial soil of India.

PubMed

Majumder, Aparajita; Bhattacharyya, Kallol; Kole, S C; Ghosh, Sagarmoy

2013-08-01

Selected arsenic-volatilizing indigenous soil bacteria were isolated and their ability to form volatile arsenicals from toxic inorganic arsenic was assessed. Approximately 37 % of AsIII (under aerobic conditions) and 30 % AsV (under anaerobic conditions) were volatilized by new bacterial isolates in 3 days. In contrast to genetically modified organism, indigenous soil bacteria was capable of removing 16 % of arsenic from contaminated soil during 60 days incubation period while applied with a low-cost organic nutrient supplement (farm yard manure).

Isolation and characterization of aerobic culturable arsenic-resistant bacteria from surfacewater and groundwater of Rautahat District, Nepal.

PubMed

Shakya, S; Pradhan, B; Smith, L; Shrestha, J; Tuladhar, S

2012-03-01

Arsenic (As) contamination of groundwater is a serious Environmental Health Management issue of drinking water sources especially in Terai region of Nepal. Many studies have reported that due to natural abundance of arsenic in the environment, various bacteria have developed different resistance mechanisms for arsenic compound. In this study, the culturable arsenic-resistant bacteria indigenous to surfacewater as well as groundwater from Rautahat District of Nepal were randomly isolated by standard plate count method on the basis of viable growth on plate count agar amended with arsenate ranging from 0, 0.5, 10, 40, 80 to 160 milligram per liter (mg/l). With respect to the morphological and biochemical tests, nine morphologically distinct potent arsenate tolerant bacteria showed relatedness with Micrococcus varians, Micrococcus roseus, Micrococcus luteus, Pseudomonas maltophilia, Pseudomonas sp., Vibrio parahaemolyticus, Bacillus cereus, Bacillus smithii 1 and Bacillus smithii 2. The isolates were capable of tolerating more than 1000 mg/l of arsenate and 749 mg/l of arsenite. Likewise, bioaccumulation capability was highest with M. roseus (85.61%) and the least with B. smithii (47.88%) indicating the potential of the organisms in arsenic resistance and most probably in bioremediation. Copyright © 2011 Elsevier Ltd. All rights reserved.

The gut microbiota of insecticide-resistant insects houses insecticide-degrading bacteria: A potential source for biotechnological exploitation.

PubMed

Almeida, Luis Gustavo de; Moraes, Luiz Alberto Beraldo de; Trigo, José Roberto; Omoto, Celso; Cônsoli, Fernando Luis

2017-01-01

The exploration of new niches for microorganisms capable of degrading recalcitrant molecules is still required. We hypothesized the gut microbiota associated with insect-resistant lines carry pesticide degrading bacteria, and predicted they carry bacteria selected to degrade pesticides they were resistant to. We isolated and accessed the pesticide-degrading capacity of gut bacteria from the gut of fifth instars of Spodoptera frugiperda strains resistant to lambda-cyhalothrin, deltamethrin, chlorpyrifos ethyl, spinosad and lufenuron, using insecticide-selective media. Sixteen isolates belonging to 10 phylotypes were obtained, from which four were also associated with the susceptible strain. However, growth of gut bacteria associated with larvae from the susceptible strain was not obtained in any of the insecticide-based selective media tested. Growth of isolates was affected by the concentration of insecticides in the media, and all grew well up to 40 μg/ml. The insecticide-degrading capacity of selected isolates was assessed by GC or LC-MS/MS analyses. In conclusion, resistant strains of S. frugiperda are an excellent reservoir of insecticide-degrading bacteria with bioremediation potential. Moreover, gut-associated bacteria are subjected to the selection pressure imposed by insecticides on their hosts and may influence the metabolization of pesticides in insects.

Bioprecipitation of Calcium Carbonate Crystals by Bacteria Isolated from Saline Environments Grown in Culture Media Amended with Seawater and Real Brine

PubMed Central

Silva-Castro, G. A.; Uad, I.; Gonzalez-Martinez, A.; Rivadeneyra, A.; Gonzalez-Lopez, J.; Rivadeneyra, M. A.

2015-01-01

The precipitation of calcium carbonate and calcium sulphate by isolated bacteria from seawater and real brine obtained in a desalination plant growth in culture media containing seawater and brine as mineral sources has been studied. However, only bioprecipitation was detected when the bacteria were grown in media with added organic matter. Biomineralization process started rapidly, crystal formation taking place in the beginning a few days after inoculation of media; roughly 90% of total cultivated bacteria showed. Six major colonies with carbonate precipitation capacity dominated bacterial community structure cultivated in heterotrophic platable bacteria medium. Taxonomic identification of these six strains through partial 16S rRNA gene sequences showed their affiliation with Gram-positive Bacillus and Virgibacillus genera. These strains were able to form calcium carbonate minerals, which precipitated as calcite and aragonite crystals and showed bacterial fingerprints or bacteria calcification. Also, carbonic anhydrase activity was observed in three of these isolated bacteria. The results of this research suggest that microbiota isolated from sea water and brine is capable of precipitation of carbonate biominerals, which can occur in situ with mediation of organic matter concentrations. Moreover, calcium carbonate precipitation ability of this microbiota could be of importance in bioremediation of CO2 and calcium in certain environments. PMID:26273646

Bioprecipitation of Calcium Carbonate Crystals by Bacteria Isolated from Saline Environments Grown in Culture Media Amended with Seawater and Real Brine.

PubMed

Silva-Castro, G A; Uad, I; Gonzalez-Martinez, A; Rivadeneyra, A; Gonzalez-Lopez, J; Rivadeneyra, M A

2015-01-01

The precipitation of calcium carbonate and calcium sulphate by isolated bacteria from seawater and real brine obtained in a desalination plant growth in culture media containing seawater and brine as mineral sources has been studied. However, only bioprecipitation was detected when the bacteria were grown in media with added organic matter. Biomineralization process started rapidly, crystal formation taking place in the beginning a few days after inoculation of media; roughly 90% of total cultivated bacteria showed. Six major colonies with carbonate precipitation capacity dominated bacterial community structure cultivated in heterotrophic platable bacteria medium. Taxonomic identification of these six strains through partial 16S rRNA gene sequences showed their affiliation with Gram-positive Bacillus and Virgibacillus genera. These strains were able to form calcium carbonate minerals, which precipitated as calcite and aragonite crystals and showed bacterial fingerprints or bacteria calcification. Also, carbonic anhydrase activity was observed in three of these isolated bacteria. The results of this research suggest that microbiota isolated from sea water and brine is capable of precipitation of carbonate biominerals, which can occur in situ with mediation of organic matter concentrations. Moreover, calcium carbonate precipitation ability of this microbiota could be of importance in bioremediation of CO2 and calcium in certain environments.

The gut microbiota of insecticide-resistant insects houses insecticide-degrading bacteria: A potential source for biotechnological exploitation

PubMed Central

de Almeida, Luis Gustavo; de Moraes, Luiz Alberto Beraldo; Trigo, José Roberto; Omoto, Celso

2017-01-01

The exploration of new niches for microorganisms capable of degrading recalcitrant molecules is still required. We hypothesized the gut microbiota associated with insect-resistant lines carry pesticide degrading bacteria, and predicted they carry bacteria selected to degrade pesticides they were resistant to. We isolated and accessed the pesticide-degrading capacity of gut bacteria from the gut of fifth instars of Spodoptera frugiperda strains resistant to lambda-cyhalothrin, deltamethrin, chlorpyrifos ethyl, spinosad and lufenuron, using insecticide-selective media. Sixteen isolates belonging to 10 phylotypes were obtained, from which four were also associated with the susceptible strain. However, growth of gut bacteria associated with larvae from the susceptible strain was not obtained in any of the insecticide-based selective media tested. Growth of isolates was affected by the concentration of insecticides in the media, and all grew well up to 40 μg/ml. The insecticide-degrading capacity of selected isolates was assessed by GC or LC-MS/MS analyses. In conclusion, resistant strains of S. frugiperda are an excellent reservoir of insecticide-degrading bacteria with bioremediation potential. Moreover, gut-associated bacteria are subjected to the selection pressure imposed by insecticides on their hosts and may influence the metabolization of pesticides in insects. PMID:28358907

Molecular identification of marine symbiont bacteria of gastropods from the waters of the Krakal coast Yogyakarta and its potential as a Multi-Drug Resistant (MDR) antibacterial agent

NASA Astrophysics Data System (ADS)

Bahry, Muhammad Syaifudien; Pringgenies, Delianis; Trianto, Agus

2017-01-01

The resistance of pathogenic bacteria may occur to many types of antibiotics, especially in cases of non-compliance use of antibiotics, which likely to allow the evolution of Multi-Drug Resistant (MDR) bacteria. Gastropods seas are marine invertebrates informed capable of production of secondary metabolites as antibacterial MDR. The purpose of the study was the isolation and identification of gastropod symbiont bacteria found in the waters of Krakal, Gunung Kidul, Yogyakarta, which has the ability to produce antibacterial compounds against MDR(Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, MRSA (methicillin-Resistant Staphylococcus aureus), Staphylococcus aureus, and Staphylococcus homunis) molecular. Stages of this research began with the isolation of bacteria, bacteria screening for anti-MDR compound, mass culture, and extraction, antibacterial activity test, DNA extraction, amplification by PCR 16S rDNA and sequencing. The results of the study showed that 19 isolates of bacteria were isolated from three species of gastropods namely Littorina scabra, Cypraea moneta and Conus ebraeus. Among them, 4 isolates showed activity against MDR test bacteria (E. coli, E. cloacae, K. pneumoniae, S. aureus and S. homunis). The highest activity was displayed by code LS.G1.8 isolate with the largest inhibition zone 15.47±0.45mm on S. humonis at 250 µg/disk concentration. Isolate CM.G2.1 showed largest inhibition zone, with 21.5±0.07mm on MRSA at 1000 µg/disk concentration and isolate the largest inhibition zone CM.G2.5 14.37±0.81mm on MRSA 14.37±0.81mm at concentrations 1000 µg/disk. The molecular identification of isolates LS.G1.8 has 99% homology with Bacillus subtilis and isolates CM.G2.1 has 99% homology with Bacillus pumillus.

Endophytic Bacteria Associated with Hieracium piloselloides: Their Potential for Hydrocarbon-Utilizing and Plant Growth-Promotion.

PubMed

Pawlik, Małgorzata; Piotrowska-Seget, Zofia

2015-01-01

The aim of this study was to assess the potential of 18 crude-oil-degrading endophytic bacteria for removal of hydrocarbons and promotion of plant growth. Strains were isolated from Hieracium piloselloides (tall hawkweed), which grows in soil heavily polluted with petroleum hydrocarbons. Bacteria from the genus Pseudomonas were abundant among the isolates. The potential for hydrocarbon degradation was evaluated by polymerase chain reaction (PCR) analyses of the genes alkB, alkH, C23O, P450, and pah. It was found that 88.89% of the endophytic bacteria contained gene-encoding polycyclic aromatic hydrocarbon (PAH) initial dioxygenase, 61% possessed the 2,3-catechol dioxygenase gene, and 39% of strains that were tested had the cytochrome P-450 hydroxylase gene. All isolates were capable of producing indole-3-acetic acid (1.8-76.4 μg/ml). Only 17% of them were able to produce siderophores, excrete cellulase, and solubilize phosphate. Hydrogen cyanide synthesis occurred in 33% of endophytic bacteria. The 1-aminocyclopropane-1-carboxylate deaminase activity in isolates that were screened was in the range of 2.6 to 74.1 μmol α-ketobutyrate/mg/h. This feature of the bacteria indicated that isolates may enhance the phytoremediation process. Data suggest that crude-oil-degrading endophytic bacteria possess potential to be promising candidates for enhancement of phytoremediation of hydrocarbon-contaminated soil. Further evaluation of these bacteria is needed in order to assess the role played in the degradation of petroleum hydrocarbons.

Lindane Bioremediation Capability of Bacteria Associated with the Demosponge Hymeniacidon perlevis.

PubMed

Loredana, Stabili; Graziano, Pizzolante; Antonio, Morgante; Carlotta, Nonnis Marzano; Caterina, Longo; Maria, Aresta Antonella; Carlo, Zambonin; Giuseppe, Corriero; Pietro, Alifano

2017-04-06

Lindane is an organochlorine pesticide belonging to persistent organic pollutants (POPs) that has been widely used to treat agricultural pests. It is of particular concern because of its toxicity, persistence and tendency to bioaccumulate in terrestrial and aquatic ecosystems. In this context, we assessed the role of bacteria associated with the sponge Hymeniacidon perlevis in lindane degradation. Seven bacteria isolates were characterized and identified. These isolates showed a remarkable capacity to utilize lindane as a sole carbon source leading to a percentage of residual lindane ranging from 3% to 13% after 12 days of incubation with the pesticide. The lindane metabolite, 1,3-6-pentachloro-cyclohexene, was identified as result of lindane degradation and determined by gas chromatography-mass spectrometry (GC-MS). The bacteria capable of lindane degradation were identified on the basis of the phenotypic characterization by morphological, biochemical and cultural tests, completed with 16S rDNA sequence analysis, and assigned to Mameliella phaeodactyli , Pseudovibrio ascidiaceicola , Oceanicaulis stylophorae , Ruegeria atlantica and to three new uncharacterized species. The results obtained are a prelude to the development of future strategies for the in situ bioremediation of lindane.

Cultivation of Anaerobic and Facultatively Anaerobic Bacteria from Spacecraft-Associated Clean Rooms▿

PubMed Central

Stieglmeier, Michaela; Wirth, Reinhard; Kminek, Gerhard; Moissl-Eichinger, Christine

2009-01-01

In the course of this biodiversity study, the cultivable microbial community of European spacecraft-associated clean rooms and the Herschel Space Observatory located therein were analyzed during routine assembly operations. Here, we focused on microorganisms capable of growing without oxygen. Anaerobes play a significant role in planetary protection considerations since extraterrestrial environments like Mars probably do not provide enough oxygen for fully aerobic microbial growth. A broad assortment of anaerobic media was used in our cultivation strategies, which focused on microorganisms with special metabolic skills. The majority of the isolated strains grew on anaerobic, complex, nutrient-rich media. Autotrophic microorganisms or microbes capable of fixing nitrogen were also cultivated. A broad range of facultatively anaerobic bacteria was detected during this study and also, for the first time, some strictly anaerobic bacteria (Clostridium and Propionibacterium) were isolated from spacecraft-associated clean rooms. The multiassay cultivation approach was the basis for the detection of several bacteria that had not been cultivated from these special environments before and also led to the discovery of two novel microbial species of Pseudomonas and Paenibacillus. PMID:19363082

Cultivation of anaerobic and facultatively anaerobic bacteria from spacecraft-associated clean rooms.

PubMed

Stieglmeier, Michaela; Wirth, Reinhard; Kminek, Gerhard; Moissl-Eichinger, Christine

2009-06-01

In the course of this biodiversity study, the cultivable microbial community of European spacecraft-associated clean rooms and the Herschel Space Observatory located therein were analyzed during routine assembly operations. Here, we focused on microorganisms capable of growing without oxygen. Anaerobes play a significant role in planetary protection considerations since extraterrestrial environments like Mars probably do not provide enough oxygen for fully aerobic microbial growth. A broad assortment of anaerobic media was used in our cultivation strategies, which focused on microorganisms with special metabolic skills. The majority of the isolated strains grew on anaerobic, complex, nutrient-rich media. Autotrophic microorganisms or microbes capable of fixing nitrogen were also cultivated. A broad range of facultatively anaerobic bacteria was detected during this study and also, for the first time, some strictly anaerobic bacteria (Clostridium and Propionibacterium) were isolated from spacecraft-associated clean rooms. The multiassay cultivation approach was the basis for the detection of several bacteria that had not been cultivated from these special environments before and also led to the discovery of two novel microbial species of Pseudomonas and Paenibacillus.

CLASSIFICATION OF PAH-DEGRADING BACTERIA BY PAH UTILIZATION PATTERNS AND THE COMPARISON OF METABOLIC PRODUCTS

EPA Science Inventory

Bacterial strains capable of using either phenanthrene, fluoranthene, or pyrene as sole carbon and energy sources were isolated from 16 different soil samples collected from the United States, Germany, and Norway. Thirty one strains were isolated on fluoranthene and the other twe...

Azoreductase activity of anaerobic bacteria isolated from human intestinal microflora.

PubMed Central

Rafii, F; Franklin, W; Cerniglia, C E

1990-01-01

A plate assay was developed for the detection of anaerobic bacteria that produce azoreductases. With this plate assay, 10 strains of anaerobic bacteria capable of reducing azo dyes were isolated from human feces and identified as Eubacterium hadrum (2 strains), Eubacterium spp. (2 species), Clostridium clostridiiforme, a Butyrivibrio sp., a Bacteroides sp., Clostridium paraputrificum, Clostridium nexile, and a Clostridium sp. The average rate of reduction of Direct Blue 15 dye (a dimethoxybenzidine-based dye) in these strains ranged from 16 to 135 nmol of dye per min per mg of protein. The enzymes were inactivated by oxygen. In seven isolates, a flavin compound (riboflavin, flavin adenine dinucleotide, or flavin mononucleotide) was required for azoreductase activity. In the other three isolates and in Clostridium perfringens, no added flavin was required for activity. Nondenaturing polyacrylamide gel electrophoresis showed that each bacterium expressed only one azoreductase isozyme. At least three types of azoreductase enzyme were produced by the different isolates. All of the azoreductases were produced constitutively and released extracellularly. Images PMID:2202258

Azoreductase activity of anaerobic bacteria isolated from human intestinal microflora.

PubMed

Rafii, F; Franklin, W; Cerniglia, C E

1990-07-01

A plate assay was developed for the detection of anaerobic bacteria that produce azoreductases. With this plate assay, 10 strains of anaerobic bacteria capable of reducing azo dyes were isolated from human feces and identified as Eubacterium hadrum (2 strains), Eubacterium spp. (2 species), Clostridium clostridiiforme, a Butyrivibrio sp., a Bacteroides sp., Clostridium paraputrificum, Clostridium nexile, and a Clostridium sp. The average rate of reduction of Direct Blue 15 dye (a dimethoxybenzidine-based dye) in these strains ranged from 16 to 135 nmol of dye per min per mg of protein. The enzymes were inactivated by oxygen. In seven isolates, a flavin compound (riboflavin, flavin adenine dinucleotide, or flavin mononucleotide) was required for azoreductase activity. In the other three isolates and in Clostridium perfringens, no added flavin was required for activity. Nondenaturing polyacrylamide gel electrophoresis showed that each bacterium expressed only one azoreductase isozyme. At least three types of azoreductase enzyme were produced by the different isolates. All of the azoreductases were produced constitutively and released extracellularly.

In Vitro Efficacy of Nonantibiotic Treatments on Biofilm Disruption of Gram-Negative Pathogens and an In Vivo Model of Infectious Endometritis Utilizing Isolates from the Equine Uterus

PubMed Central

McCue, Patrick M.; Borlee, Grace I.; Loncar, Kristen D.; Hennet, Margo L.

2015-01-01

In this study, we evaluated the ability of the equine clinical treatments N-acetylcysteine, EDTA, and hydrogen peroxide to disrupt in vitro biofilms and kill equine reproductive pathogens (Escherichia coli, Pseudomonas aeruginosa, or Klebsiella pneumoniae) isolated from clinical cases. N-acetylcysteine (3.3%) decreased biofilm biomass and killed bacteria within the biofilms of E. coli isolates. The CFU of recoverable P. aeruginosa and K. pneumoniae isolates were decreased, but the biofilm biomass was unchanged. Exposure to hydrogen peroxide (1%) decreased the biofilm biomass and reduced the CFU of E. coli isolates, K. pneumoniae isolates were observed to have a reduction in CFU, and minimal effects were observed for P. aeruginosa isolates. Chelating agents (EDTA formulations) reduced E. coli CFU but were ineffective at disrupting preformed biofilms or decreasing the CFU of P. aeruginosa and K. pneumoniae within a biofilm. No single nonantibiotic treatment commonly used in equine veterinary practice was able to reduce the CFU and biofilm biomass of all three Gram-negative species of bacteria evaluated. An in vivo equine model of infectious endometritis was also developed to monitor biofilm formation, utilizing bioluminescence imaging with equine P. aeruginosa isolates from this study. Following infection, the endometrial surface contained focal areas of bacterial growth encased in a strongly adherent “biofilm-like” matrix, suggesting that biofilms are present during clinical cases of infectious equine endometritis. Our results indicate that Gram-negative bacteria isolated from the equine uterus are capable of producing a biofilm in vitro, and P. aeruginosa is capable of producing biofilm-like material in vivo. PMID:26719448

In Vitro Efficacy of Nonantibiotic Treatments on Biofilm Disruption of Gram-Negative Pathogens and an In Vivo Model of Infectious Endometritis Utilizing Isolates from the Equine Uterus.

PubMed

Ferris, Ryan A; McCue, Patrick M; Borlee, Grace I; Loncar, Kristen D; Hennet, Margo L; Borlee, Bradley R

2016-03-01

In this study, we evaluated the ability of the equine clinical treatments N-acetylcysteine, EDTA, and hydrogen peroxide to disrupt in vitro biofilms and kill equine reproductive pathogens (Escherichia coli, Pseudomonas aeruginosa, or Klebsiella pneumoniae) isolated from clinical cases. N-acetylcysteine (3.3%) decreased biofilm biomass and killed bacteria within the biofilms of E. coli isolates. The CFU of recoverable P. aeruginosa and K. pneumoniae isolates were decreased, but the biofilm biomass was unchanged. Exposure to hydrogen peroxide (1%) decreased the biofilm biomass and reduced the CFU of E. coli isolates, K. pneumoniae isolates were observed to have a reduction in CFU, and minimal effects were observed for P. aeruginosa isolates. Chelating agents (EDTA formulations) reduced E. coli CFU but were ineffective at disrupting preformed biofilms or decreasing the CFU of P. aeruginosa and K. pneumoniae within a biofilm. No single nonantibiotic treatment commonly used in equine veterinary practice was able to reduce the CFU and biofilm biomass of all three Gram-negative species of bacteria evaluated. An in vivo equine model of infectious endometritis was also developed to monitor biofilm formation, utilizing bioluminescence imaging with equine P. aeruginosa isolates from this study. Following infection, the endometrial surface contained focal areas of bacterial growth encased in a strongly adherent "biofilm-like" matrix, suggesting that biofilms are present during clinical cases of infectious equine endometritis. Our results indicate that Gram-negative bacteria isolated from the equine uterus are capable of producing a biofilm in vitro, and P. aeruginosa is capable of producing biofilm-like material in vivo. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Potency of Amylase-producing Bacteria and Optimization Amylase Activities

NASA Astrophysics Data System (ADS)

Indriati, G.; Megahati, R. R. P.; Rosba, E.

2018-04-01

Enzymes are capable to act as biocatalyst for a wide variety of chemical reactions. Amylase have potential biotechnological applications in a wide range of industrial processes and account for nearly 30% of the world’s enzyme market. Amylase are extracellular enzymes that catalyze the hydrolysis of internal α-1,4-glycosidic linkages in starch to dextrin, and other small carbohydrate molecules constituted of glucose units. Although enzymes are produced from animal and plant sources, the microbial sources are generally the most suitable for commercial applications. Bacteria from hot springs is widely used as a source of various enzymes, such as amylase. But the amount of amylase-producing bacteria is still very limited. Therefore it is necessary to search sources of amylase-producing bacteria new, such as from hot springs Pariangan. The purpose of this study was to isolation of amylase-producing bacteria from Pariangan hot spring, West Sumatera and amylase activity optimization. The results were obtained 12 isolates of thermophilic bacteria and 5 isolates of amyalse-producing bacteria with the largest amylolytic index of 3.38 mm. The highest amylase activity was obtained at 50°C and pH 7.5.

Quinones are growth factors for the human gut microbiota.

PubMed

Fenn, Kathrin; Strandwitz, Philip; Stewart, Eric J; Dimise, Eric; Rubin, Sarah; Gurubacharya, Shreya; Clardy, Jon; Lewis, Kim

2017-12-20

The human gut microbiome has been linked to numerous components of health and disease. However, approximately 25% of the bacterial species in the gut remain uncultured, which limits our ability to properly understand, and exploit, the human microbiome. Previously, we found that growing environmental bacteria in situ in a diffusion chamber enables growth of uncultured species, suggesting the existence of growth factors in the natural environment not found in traditional cultivation media. One source of growth factors proved to be neighboring bacteria, and by using co-culture, we isolated previously uncultured organisms from the marine environment and identified siderophores as a major class of bacterial growth factors. Here, we employ similar co-culture techniques to grow bacteria from the human gut microbiome and identify novel growth factors. By testing dependence of slow-growing colonies on faster-growing neighboring bacteria in a co-culture assay, eight taxonomically diverse pairs of bacteria were identified, in which an "induced" isolate formed a gradient of growth around a cultivatable "helper." This set included two novel species Faecalibacterium sp. KLE1255-belonging to the anti-inflammatory Faecalibacterium genus-and Sutterella sp. KLE1607. While multiple helper strains were identified, Escherichia coli was also capable of promoting growth of all induced isolates. Screening a knockout library of E. coli showed that a menaquinone biosynthesis pathway was required for growth induction of Faecalibacterium sp. KLE1255 and other induced isolates. Purified menaquinones induced growth of 7/8 of the isolated strains, quinone specificity profiles for individual bacteria were identified, and genome analysis suggests an incomplete menaquinone biosynthetic capability yet the presence of anaerobic terminal reductases in the induced strains, indicating an ability to respire anaerobically. Our data show that menaquinones are a major class of growth factors for bacteria from the human gut microbiome. These organisms are taxonomically diverse, including members of the genus Faecalibacterium, Bacteroides, Bilophila, Gordonibacter, and Sutterella. This suggests that loss of quinone biosynthesis happened independently in many lineages of the human microbiota. Quinones can be used to improve existing bacterial growth media or modulate the human gut microbiota by encouraging the growth of important symbionts, such as Faecalibacterium species.

Isolation and Molecular Identification of Streptomyces spp. with Antibacterial Activity from Northwest of Iran

PubMed Central

Maleki, Hadi; Dehnad, Alireza; Hanifian, Shahram; Khani, Sajjad

2013-01-01

Introduction: Streptomyces are a group of prokaryotes that are usually found in all types of ecosystems including water and soil. This group of bacteria is noteworthy as antibiotic producers; so the isolation and characterization of new species seemed to be crucial in introduction of markedly favorable antibiotics. Therefore, in this study we aim to isolate and characterize novel strains of Streptomyces with high antibiotic production capability. Methods: To achieve this goal, from 140 isolates collected throughout northwest of Iran, 12 selected Streptomyces isolates which exhibited high antibacterial activity against pathogenic bacteria were subjected to PCR reaction for identification via 16S rDNA gene and random amplified polymorphic DNA (RAPD) pattern analysis. Results: Analysis of morphological and biochemical characteristics and the 16S rDNA gene sequence indicated that all 12 selected isolates belonged to the genus Streptomyces. Moreover, screening of the isolates with regard to their antimicrobial activity against indicator bacteria as well as their classification using RAPD analysis revealed that G614C1 and K36C5 isolates have considerable antimicrobial activity and high similarity to Streptomyces coelicolor and Sreptomyces albogriseolus, respectively. Conclusion: Since many isolates in this study showed inhibitory effects against pathogenic bacteria, soil of northwest of Iran could be used as a rich source to be explored for novel Streptomyces strains with high potency of antibiotic production. PMID:24163805

Isolation and Molecular Identification of Streptomyces spp. with Antibacterial Activity from Northwest of Iran.

PubMed

Maleki, Hadi; Dehnad, Alireza; Hanifian, Shahram; Khani, Sajjad

2013-01-01

Streptomyces are a group of prokaryotes that are usually found in all types of ecosystems including water and soil. This group of bacteria is noteworthy as antibiotic producers; so the isolation and characterization of new species seemed to be crucial in introduction of markedly favorable antibiotics. Therefore, in this study we aim to isolate and characterize novel strains of Streptomyces with high antibiotic production capability. To achieve this goal, from 140 isolates collected throughout northwest of Iran, 12 selected Streptomyces isolates which exhibited high antibacterial activity against pathogenic bacteria were subjected to PCR reaction for identification via 16S rDNA gene and random amplified polymorphic DNA (RAPD) pattern analysis. Analysis of morphological and biochemical characteristics and the 16S rDNA gene sequence indicated that all 12 selected isolates belonged to the genus Streptomyces. Moreover, screening of the isolates with regard to their antimicrobial activity against indicator bacteria as well as their classification using RAPD analysis revealed that G614C1 and K36C5 isolates have considerable antimicrobial activity and high similarity to Streptomyces coelicolor and Sreptomyces albogriseolus, respectively. Since many isolates in this study showed inhibitory effects against pathogenic bacteria, soil of northwest of Iran could be used as a rich source to be explored for novel Streptomyces strains with high potency of antibiotic production.

Electricity Generation in Microbial Fuel Cell (MFC) by Bacterium Isolated from Rice Paddy Field Soil

NASA Astrophysics Data System (ADS)

Fakhirruddin, Fakhriah; Amid, Azura; Salim, Wan Wardatul Amani Wan; Suhaida Azmi, Azlin

2018-03-01

Microbial fuel cell (MFC) is an alternative approach in generating renewable energy by utilising bacteria that will oxidize organic or inorganic substrates, producing electrons yielded as electrical energy. Different species of exoelectrogenic bacteria capable of generating significant amount of electricity in MFC has been identified, using various organic compounds for fuel. Soil sample taken from rice paddy field is proven to contain exoelectrogenic bacteria, thus electricity generation using mixed culture originally found in the soil, and pure culture isolated from the soil is studied. This research will isolate the exoelectrogenic bacterial species in the rice paddy field soil responsible for energy generation. Growth of bacteria isolated from the MFC is observed by measuring the optical density (OD), cell density weight (CDW) and viable cell count. Mixed bacterial species found in paddy field soil generates maximum power of 77.62 μW and 0.70 mA of current. In addition, the research also shows that the pure bacterium in rice paddy field soil can produce maximum power and current at 51.32 μW and 0.28 mA respectively.

Characterization of bromate-reducing bacterial isolates and their potential for drinking water treatment.

PubMed

Davidson, Andrew N; Chee-Sanford, Joanne; Lai, Hoi Yi Mandy; Ho, Chi-hua; Klenzendorf, J Brandon; Kirisits, Mary Jo

2011-11-15

The objective of the current study was to isolate and characterize several bromate-reducing bacteria and to examine their potential for bioaugmentation to a drinking water treatment process. Fifteen bromate-reducing bacteria were isolated from three sources. According to 16S rRNA gene sequencing, the bromate-reducing bacteria are phylogenetically diverse, representing the Actinobacteria, Bacteroidetes, Firmicutes, and α-, β-, and γ-Proteobacteria. The broad diversity of bromate-reducing bacteria suggests the widespread capability for microbial bromate reduction. While the cometabolism of bromate via nitrate reductase and (per)chlorate reductase has been postulated, five of our bromate-reducing isolates were unable to reduce nitrate or perchlorate. This suggests that a bromate-specific reduction pathway might exist in some microorganisms. Bioaugmentation of activated carbon filters with eight of the bromate-reducing isolates did not significantly decrease start-up time or increase bromate removal as compared to control filters. To optimize bromate reduction in a biological drinking water treatment process, the predominant mechanism of bromate reduction (i.e., cometabolic or respiratory) needs to be assessed so that appropriate measures can be taken to improve bromate removal. Copyright © 2011 Elsevier Ltd. All rights reserved.

Characterization of bacterial diversity associated with calcareous deposits and drip-waters, and isolation of calcifying bacteria from two Colombian mines.

PubMed

García G, Mariandrea; Márquez G, Marco Antonio; Moreno H, Claudia Ximena

2016-01-01

Bacterial carbonate precipitation has implications in geological processes and important biotechnological applications. Bacteria capable of precipitating carbonates have been isolated from different calcium carbonate deposits (speleothems) in caves, soil, freshwater and seawater around the world. However, the diversity of bacteria from calcareous deposits in Colombia, and their ability to precipitate carbonates, remains unknown. In this study, conventional microbiological methods and molecular tools, such as temporal temperature gradient electrophoresis (TTGE), were used to assess the composition of bacterial communities associated with carbonate deposits and drip-waters from two Colombian mines. A genetic analysis of these bacterial communities revealed a similar level of diversity, based on the number of bands detected using TTGE. The dominant phylogenetic affiliations of the bacteria, determined using 16S rRNA gene sequencing, were grouped into two phyla: Proteobacteria and Firmicutes. Within these phyla, seven genera were capable of precipitating calcium carbonates: Lysinibacillus, Bacillus, Strenotophomonas, Brevibacillus, Methylobacterium, Aeromicrobium and Acinetobacter. FTIR and SEM/EDX were used to analyze calcium carbonate crystals produced by isolated Acinetobacter gyllenbergii. The results showed that rhombohedral and angular calcite crystals with sizes of 90μm were precipitated. This research provides information regarding the presence of complex bacterial communities in secondary carbonate deposits from mines and their ability to precipitate calcium carbonate from calcareous deposits of Colombian mines. Copyright © 2015 Elsevier GmbH. All rights reserved.

ATMOSPHERIC NITROGEN FIXATION BY METHANE-OXIDIZING BACTERIA

PubMed Central

Davis, J. B.; Coty, V. F.; Stanley, J. P.

1964-01-01

Davis, J. B. (Socony Mobil Oil Co., Inc., Dallas, Tex.), V. F. Coty, and J. P. Stanley. Atmospheric nitrogen fixation by methane-oxidizing bacteria. J. Bacteriol. 88:468–472. 1964.—Methane-oxidizing bacteria capable of fixing atmospheric nitrogen were isolated from garden soil, pond mud, oil field soil, and soil exposed to natural gas, indicating a rather wide prevalence in nature. This may explain the high concentration of organic nitrogen commonly found in soils exposed to gas leakage from pipelines or natural-gas seeps. Added molybdenum was a requirement for growth in a nitrogen-free mineral salts medium. All nitrogen-fixing, methane-oxidizing bacteria isolated were gram-negative, nonsporeforming, usually motile rods. Colonies were light yellow, yellow, or white. The most common isolate, which formed light-yellow colonies, is referred to as Pseudomonas methanitrificans sp. n., and is distinguished from Pseudomonas (Methanomonas) methanica by nitrogen-fixing ability and a preponderance of poly-β-hydroxybutyrate in the cellular lipid fraction. Images PMID:14203365

Isolation and characterization of bacteriocinogenic lactic bacteria from M-Tuba and Tepache, two traditional fermented beverages in México

PubMed Central

de la Fuente-Salcido, Norma M; Castañeda-Ramírez, José Cristobal; García-Almendárez, Blanca E; Bideshi, Dennis K; Salcedo-Hernández, Rubén; Barboza-Corona, José E

2015-01-01

Mexican Tuba (M-Tuba) and Tepache are Mexican fermented beverages prepared mainly with pineapple pulp and coconut palm, respectively. At present, reports on the microbiota and nutritional effects of both beverages are lacking. The purpose of this study was to determine whether M-Tuba and Tepache contain cultivable lactic acid bacteria (LAB) capable of producing bacteriocins. Tepache and M-Tuba contain mesophilic aerobic bacteria, LAB, and yeast. Bacillus subtilis, Listeria monocytogenes, Listeria innocua, Streptococcus agalactiae, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium, and Salmonella spp, were the microorganisms most susceptible to metabolites produced by bacterial isolates. M-Tuba and Tepache contain bacteria that harbor genes coding for nisin and enterocin, but not pediocin. The presence of Lactococcus lactis and E. faecium in M-Tuba and Tepache, was identified by 16S rDNA. These bacteria produced bacteriocins of ∼3.5 kDa and 4.0–4.5 kDa, respectively. Partial purified bacteriocins showed inhibitory effect against Micrococcus luteus, L. monocytogenes, L. innocua, Str. agalactiae, S. aureus, Bacillus cereus, B. subtilis, E. faecalis, and K. pneumoniae. We characterized, for the first time, cultivable microbiota of M-Tuba and Tepache, and specifically, identified candidate lactic bacteria (LAB) present in these beverages that were capable of synthesizing antimicrobial peptides, which collectively could provide food preservative functions. PMID:26405529

[Diversity and enzyme-producing activity of culturable halophilic bacteria in Daishan Saltern of East China].

PubMed

Yang, Dan-Dan; Li, Qian; Huang, Jing-Jing; Chen, Min

2012-11-01

Soil and saline water samples were collected from the Daishan Saltern of East China, and the halophilic bacteria were isolated and cultured by using selective media, aimed to investigate the diversity and enzyme-producing activity of culturable halophilic bacteria in saltern environment. A total of 181 strains were isolated by culture-dependent method. Specific primers were used to amplify the 16S rRNA gene of bacteria and archaea. The operation taxonomy units (OTUs) were determined by ARDRA method, and the representative strain of each OTU was sequenced. The phylogenetic position of all the isolated strains was determined by 16S rRNA sequencing. The results showed that the isolated 181 strains displayed 21 operational taxonomic units (OTUs), of which, 12 OTUs belonged to halophilic bacteria, and the others belonged to halophilic archaea. Phylogenetic analysis indicated that there were 7 genera presented among the halophilic bacteria group, and 4 genera presented among the halophilic archaea group. The dominant halophilic strains were of Halomonas and Haloarcula, with 46.8% in halophilic bacteria and 49.1% in halophilic archaea group, respectively. Enzyme-producing analysis indicated that most strains displayed enzyme-producing activity, including the activities of producing amylase, proteinase and lipase, and the dominant strains capable of enzyme-producing were of Haloarcula. Our results showed that in the environment of Daishan Saltern, there existed a higher diversity of halophilic bacteria, being a source sink for screening enzyme-producing bacterial strains.

Biodegradation of kraft lignin by newly isolated Klebsiella pneumoniae, Pseudomonas putida, and Ochrobactrum tritici strains.

PubMed

Xu, Zhaoxian; Qin, Ling; Cai, Mufeng; Hua, Wenbo; Jin, Mingjie

2018-05-01

Bacterial systems have drawn an increasing amount of attention on lignin valorization due to their rapid growth and powerful environmental adaptability. In this study, Klebsiella pneumoniae NX-1, Pseudomonas putida NX-1, and Ochrobactrum tritici NX-1 with ligninolytic potential were isolated from leaf mold samples. Their ligninolytic capabilities were determined by measuring (1) the cell growth on kraft lignin as the sole carbon source, (2) the decolorization of kraft lignin and lignin-mimicking dyes, (3) the micro-morphology changes and transformations of chemical groups in kraft lignin, and (4) the ligninolytic enzyme activities of these three isolates. To the best of our knowledge, this is the first report that Ochrobactrum tritici species can depolymerize and metabolize lignin. Moreover, laccase, lignin peroxidase, and Mn-peroxidase showed high activities in P. putida NX-1. Due to their excellent ligninolytic capabilities, these three bacteria are important supplements to ligninolytic bacteria library and could be valuable in lignin valorization.

Isolation and phylogenetic characterization of iron-sulfur-oxidizing heterotrophic bacteria indigenous to nickel laterite ores of Sulawesi, Indonesia: Implications for biohydrometallurgy

NASA Astrophysics Data System (ADS)

Chaerun, Siti Khodijah; Hung, Sutina; Mubarok, Mohammad Zaki; Sanwani, Edy

2015-09-01

The main objective of this study was to isolate and phylogenetically identify the indigenous iron-sulfur-oxidizing heterotrophic bacteria capable of bioleaching nickel from laterite mineral ores. The bacteria were isolated from a nickel laterite mine area in South Sulawesi Province, Indonesia. Seven bacterial strains were successfully isolated from laterite mineral ores (strains SKC/S-1 to SKC/S-7) and they were capable of bioleaching of nickel from saprolite and limonite ores. Using EzTaxon-e database, the 16S rRNA gene sequences of the seven bacterial strains were subjected to phylogenetic analysis, resulting in a complete hierarchical classification system, and they were identified as Pseudomonas taiwanensis BCRC 17751 (98.59% similarity), Bacillus subtilis subsp. inaquosorum BGSC 3A28 (99.14% and 99.32% similarities), Paenibacillus pasadenensis SAFN-007 (98.95% and 99.33% similarities), Bacillus methylotrophicus CBMB 205 (99.37% similarity), and Bacillus altitudinis 41KF2b (99.37% similarity). It is noteworthy that members of the phylum Firmicutes (in particular the genus Bacillus) predominated in this study, therefore making them to have the high potential to be candidates for the bioleaching of nickel from laterite mineral ores. To our knowledge, this is the first report on the predominance of the phylum Firmicutes in the Sulawesi laterite mineral ores.

Removal enactment of organo-phosphorous pesticide using bacteria isolated from domestic sewage.

PubMed

Shabbir, Md; Singh, Mukesh; Maiti, Swati; Kumar, Sunil; Saha, Samar K

2018-05-01

Three bacteria (MS I, II and III) i.e., Pseudomonas aeruginosa (KY781886), Enterobactor ludwigii (KX881423) and Enterobacter cloacae (KX881513) isolated from domestic sewage were identified on the basis of 16S rDNA sequencing and are capable to growth in the presence of organo-phosphorous pesticide (chlorpyrifos). The mega plasmid size >23 kb was found in MS I and III. Biosurfactants of the significant amount were produced by three isolates. The ability of the isolates to degrade pesticide over 3 days in the presence of pesticides containing chlorpyrifos as the active component was estimated. Results of UV-visible, FTIR spectroscopy and GC-MS studies confirmed the removal of chlorpyrifos rather than degradation. Pesticide uptake results showed chlorpyrifos in intracellular components and bound to the cell surface in its native state. Removal of pesticide from soil was also recorded by these bacteria. Microbial treated pesticide did not have any effect on Vigna radita seedlings and goat erythrocytes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Isolation and characterisation of obligately anaerobic, lipolytic bacteria from the rumen of red deer.

PubMed

Jarvis, G N; Strömpl, C; Moore, E R; Thiele, J H

1998-03-01

Two Gram-positive, obligately anaerobic, lipolytic bacteria, isolates LIP4 and LIP5, were obtained from the rumen contents of juvenile red deer. These mesophilic bacterial strains were capable of hydrolysing the neutral lipids, tallow, tripalmitin and oliver oil, into their constituent free long-chain fatty acid and glycerol moieties. The latter compound was dissimilated by both isolates, with isolate LIP4 producing propionate as the predominant product, while isolate LIP5 produced acetate, ethanol and succinate. The lactate-utilising isolate LIP4 grew on a limited range of saccharide substrates including glucose, fructose and ribose, and exhibited an unusual cell wall structure and morphology. The isolate LIP5 grew upon a wider range of saccharides, but was unable to use lactate as a substrate. Based upon phenotypic and 16S rRNA gene sequence analyses, isolate LIP4 clusters with species in the genus Propionibacterium, while isolate LIP5 is a member of clostridial cluster XIVa.

Phylogenetic Affiliation of Soil Bacteria That Degrade Aliphatic Polyesters Available Commercially as Biodegradable Plastics

PubMed Central

Suyama, Tetsushi; Tokiwa, Yutaka; Ouichanpagdee, Pornpimol; Kanagawa, Takahiro; Kamagata, Yoichi

1998-01-01

Thirty-nine morphologically different soil bacteria capable of degrading poly(β-hydroxyalkanoate), poly(ɛ-caprolactone), poly(hexamethylene carbonate), or poly(tetramethylene succinate) were isolated. Their phylogenetic positions were determined by 16S ribosomal DNA sequencing, and all of them fell into the classes Firmicutes and Proteobacteria. Determinations of substrate utilization revealed characteristic patterns of substrate specificities. PMID:9835597

Characterization of tetracycline-resistant bacteria in an urbanizing subtropical watershed.

PubMed

Sullivan, B A; Gentry, T; Karthikeyan, R

2013-09-01

The objective of this study was to determine whether varying levels of urbanization influence the dominant bacterial species of mildly resistant (0·03 mmol l(-1) tetracycline) and highly resistant (0·06 mmol l(-1) tetracycline) bacteria in sediment and water. Also, the level of urbanization was further evaluated to determine whether the diversity of tetracycline resistance genes present in the isolates and the capability of transferring their resistance were influenced. Sediment and water samples collected from five sampling sites were plated in triplicate on nutrient agar plates with a mild dose (0·03 mmol l(-1) ) and a high dose (0·06 mmol l(-1) ) of tetracycline. Five colonies from each plate plus an additional five from each triplicate group were randomly selected and isolated on nutrient agar containing 0·03 mmol l(-1) tetracycline (400 isolates). The isolates were identified by 16S rRNA gene sequencing and comparison to GenBank using blast. The isolates were also screened for 15 tetracycline resistance genes using a multiplex PCR assay and their ability to transfer resistance through conjugation experiments using a kanamycin-resistant Escherichia. coli K-12 strain labelled with a green fluorescent protein gene. Results from this study indicate that the dominant resistant organisms in this watershed are Acinetobacter spp., Chryseobacterium spp., Serratia spp., Pseudomonas spp., Aeromonas spp. and E. coli. All of these organisms are Gram negative and are closely related to pathogenic species. A majority of the isolates (66%) were capable of transferring their resistance, and there was a greater incidence of tet resistance transfer with increasing urbanization. Also, it was determined that the dominant resistance genes in the watershed are tet(W) and tet(A). Urbanization significantly affected dominant tetracycline-resistant bacteria species, but did not affect dominant resistance genes. There was correlation between increased urbanization with an increase in the ability to transfer tetracycline resistance. This indicates that urban areas may select for bacterial species that are capable of transferring resistance. These results indicate that urbanization influences the occurrence of tetracycline-resistant bacteria and the potential for transfer of resistance genes. © 2013 The Society for Applied Microbiology.

Diversity of protease-producing marine bacteria from sub-antarctic environments.

PubMed

Cristóbal, Héctor Antonio; López, Maria Alejandra; Kothe, Erika; Abate, Carlos Mauricio

2011-12-01

From seawater and the intestines of benthonic organisms collected from the Beagle Channel, Argentina, 230 marine bacteria were isolated. Cultivable bacteria were characterized and classified as psychrotolerant, whereas few isolates were psychrophiles. These isolates were capable of producing proteases at 4 and 15 °C under neutral (pH 7.0), alkaline (pH 10.0) and acidic (pH 4.5) conditions on different media, revealing 62, 33 and 22% producers at cold and 84, 47 and 33% producers at low temperatures, respectively. More protease-producing strains (67%) were detected when isolated from benthic invertebrates as compared to seawater (33%), with protease production under neutral conditions resulting in milk protein hydrolysis halos between 27 and 30 ± 2 mm in diameter. Using sterile 0.22 μm membrane filters, 29 isolates exhibiting extracellular protease activity were detected. These were grouped into six operational taxonomic units by restriction analysis and identified based on 16S rDNA as γ-proteobacteria of the genera Pseudoalteromonas, Pseudomonas, Shewanella, Alteromonas, Aeromonas, and Serratia. Plasmids were found to be harbored by eight strains, mainly within the isolates from benthonic organisms. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

PHB-degrading bacteria isolated from the gastrointestinal tract of aquatic animals as protective actors against luminescent vibriosis.

PubMed

Liu, Yiying; De Schryver, Peter; Van Delsen, Bart; Maignien, Loïs; Boon, Nico; Sorgeloos, Patrick; Verstraete, Willy; Bossier, Peter; Defoirdt, Tom

2010-10-01

The use of poly-β-hydroxybutyrate (PHB) was shown to be successful in increasing the resistance of brine shrimp against pathogenic infections. In this study, we isolated for the first time PHB-degrading bacteria from a gastrointestinal environment. Pure strains of PHB-degrading bacteria were isolated from Siberian sturgeon, European sea bass and giant river prawn. The capability of selected isolates to degrade PHB was confirmed in at least two of three setups: (1) growth in minimal medium containing PHB as the sole carbon (C) source, (2) production of clearing zones on minimal agar containing PHB as the sole C source and (3) degradation of PHB (as determined by HPLC analysis) in 10% Luria-Bertani medium containing PHB. Challenge tests showed that the PHB-degrading activity of the selected isolates increased the survival of brine shrimp larvae challenged to a pathogenic Vibrio campbellii strain by a factor 2-3. Finally, one of the PHB-degrading isolates from sturgeon showed a double biocontrol effect because it was also able to inactivate acylhomoserine lactones, a type of quorum-sensing molecule that regulates the virulence of different pathogenic bacteria. Thus, the combined supplementation of a PHB-degrading bacterium and PHB as a synbioticum provides perspectives for improving the gastrointestinal health of aquatic animals. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Final Scientific Report: Bacterial Nanowires and Extracellular Electron Transfer to Heavy Metals and Radionuclides by Bacterial Isolates from DOE Field Research Centers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nealson, Kenneth

This proposal involved the study of bacteria capable of transferring electrons from the bacterial cells to electron acceptors located outside the cell. These could be either insoluble minerals that were transformed into soluble products upon the addition of electrons, or they could be soluble salts like uranium or chromium, that become insoluble upon the addition of electrons. This process is called extracellular electron transport or EET, and can be done directly by cellular contact, or via conductive appendages called bacterial nanowires. In this work we examined a number of different bacteria for their ability to perform EET, and also lookedmore » at their ability to produce conductive nanowires that can be used for EET at a distance away from the EET-capable cells. In the work, new bacteria were isolated, new abilities of EET were examined, and many new methods were developed, and carefully described in the literature. These studies set the stage for future work dealing with the bioremediation of toxic metals like uranium and chromium. They also point out that EET (and conductive nanowires) are far more common that had been appreciated, and may be involved with energy transfer not only in sediments, but in symbioses between different bacteria, and in symbiosis/pathogenesis between bacteria and higher organisms.« less

Assessment of active bacteria metabolizing phenolic acids in the peanut (Arachis hypogaea L.) rhizosphere.

PubMed

Liu, Jinguang; Wang, Xingxiang; Zhang, Taolin; Li, Xiaogang

2017-12-01

Phenolic acids can enhance the mycotoxin production and activities of hydrolytic enzymes related to pathogenicity of soilborne fungus Fusarium oxysporum. However, characteristics of phenolic acid-degrading bacteria have not been investigated. The objectives of this study were to isolate and characterize bacteria capable of growth on benzoic and vanillic acids as the sole carbon source in the peanut rhizosphere. Twenty-four bacteria were isolated, and the identification based on 16S rRNA gene sequencing revealed that pre-exposure to phenolic acids before sowing shifted the dominant culturable bacterial degraders from Arthrobacter to Burkholderia stabilis-like isolates. Both Arthrobacter and B. stabilis-like isolates catalysed the aromatic ring cleavage via the ortho pathway, and Arthrobacter isolates did not exhibit higher C12O enzyme activity than B. stabilis-like isolates. The culture filtrate of Fusarium sp. ACCC36194 caused a strong inhibition of Arthrobacter growth but not B. stabilis-like isolates. Additionally, Arthrobacter isolates responded differently to the culture filtrates of B. stabilis-like isolates. The Arthrobacter isolates produced higher indole acetic acid (IAA) levels than B. stabilis-like isolates, but B. stabilis-like isolates were also able to produce siderophores, solubilize mineral phosphate, and exert an antagonistic activity against peanut root rot pathogen Fusarium sp. ACCC36194. Results indicate that phenolic acids can shift their dominant culturable bacterial degraders from Arthrobacter to Burkholderia species in the peanut rhizosphere, and microbial interactions might lead to the reduction of culturable Arthrobacter. Furthermore, increasing bacterial populations metabolizing phenolic acids in monoculture fields might be a control strategy for soilborne diseases caused by Fusarium spp. Copyright © 2017 Elsevier GmbH. All rights reserved.

Identification of Antimony- and Arsenic-Oxidizing Bacteria Associated with Antimony Mine Tailing

PubMed Central

Hamamura, Natsuko; Fukushima, Koh; Itai, Takaaki

2013-01-01

Antimony (Sb) is a naturally occurring toxic element commonly associated with arsenic (As) in the environment and both elements have similar chemistry and toxicity. Increasing numbers of studies have focused on microbial As transformations, while microbial Sb interactions are still not well understood. To gain insight into microbial roles in the geochemical cycling of Sb and As, soils from Sb mine tailing were examined for the presence of Sb- and As-oxidizing bacteria. After aerobic enrichment culturing with AsIII (10 mM) or SbIII (100 μM), pure cultures of Pseudomonas- and Stenotrophomonas-related isolates with SbIII oxidation activities and a Sinorhizobium-related isolate capable of AsIII oxidation were obtained. The AsIII-oxidizing Sinorhizobium isolate possessed the aerobic arsenite oxidase gene (aioA), the expression of which was induced in the presence of AsIII or SbIII. However, no SbIII oxidation activity was detected from the Sinorhizobium-related isolate, suggesting the involvement of different mechanisms for Sb and As oxidation. These results demonstrate that indigenous microorganisms associated with Sb mine soils are capable of Sb and As oxidation, and potentially contribute to the speciation and mobility of Sb and As in situ. PMID:23666539

Isolation of oxalotrophic bacteria associated with Varroa destructor mites.

PubMed

Maddaloni, M; Pascual, D W

2015-11-01

Bacteria associated with varroa mites were cultivated and genotyped by 16S RNA. Under our experimental conditions, the cultivable bacteria were few in number, and most of them proved to be fastidious to grow. Cultivation with seven different media under O2 /CO2 conditions and selection for colony morphology yielded a panel of species belonging to 13 different genera grouped in two different phyla, proteobacteria and actinobacteria. This study identified one species of actinobacteria that is a known commensal of the honey bee. Some isolates are oxalotrophic, a finding that may carry ramifications into the use of oxalic acid to control the number of phoretic mites in the managed colonies of honey bees. Oxalic acid, legally or brevi manu, is widely used to control phoretic Varroa destructor mites, a major drive of current honey bees' colony losses. Unsubstantiated by sanctioned research are rumours that in certain instances oxalic acid is losing efficacy, forcing beekeepers to increase the frequency of treatments. This investigation fathoms the hypothesis that V. destructor associates with bacteria capable of degrading oxalic acid. The data show that indeed oxalotrophy, a rare trait among bacteria, is common in bacteria that we isolated from V. destructor mites. This finding may have ramifications in the use of oxalic acid as a control agent. © 2015 The Society for Applied Microbiology.

Identification of astilbin metabolites produced by human intestinal bacteria using UPLC-Q-TOF/MS.

PubMed

Zhao, Min; Xu, Jun; Qian, Dawei; Guo, Jianming; Jiang, Shu; Shang, Er-xin; Duan, Jin-ao

2014-07-01

Astilbin, mainly isolated from a commonly used herbal medicine, Smilax glabra Roxb (SGR), exhibits a variety of pharmacological activities and biological effects. It is metabolized by intestinal bacteria after oral administration which leads to the variation of ethnopharmacological profile of this traditional medicine. However, little is known on the interactions of this active compound with intestinal bacteria, which would be very helpful in unravelling how SGR works. In this study, different pure bacteria from human feces were isolated and were used to investigate their conversion capability of astilbin. Ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technique combined with Metabolynx(TM) software was used to analyze astilbin and its metabolites. The parent compound and two metabolites (quercetin and eriodictyol) were detected in the isolated bacterial samples compared with blank samples. Quercetin was present in Enterococcus sp. 8B, 8-2 and 9-2 samples. Eriodictyol was only identified in Enterococcus sp. 8B sample. The metabolic routes and metabolites of astilbin produced by the different intestinal bacteria are reported for the first time. This will be useful for the investigation of the pharmacokinetic study of astilbin in vivo and the role of different intestinal bacteria in the metabolism of natural compounds. Copyright © 2014 John Wiley & Sons, Ltd.

Calcium Carbonate Precipitation by Bacillus and Sporosarcina Strains Isolated from Concrete and Analysis of the Bacterial Community of Concrete.

PubMed

Kim, Hyun Jung; Eom, Hyo Jung; Park, Chulwoo; Jung, Jaejoon; Shin, Bora; Kim, Wook; Chung, Namhyun; Choi, In-Geol; Park, Woojun

2016-03-01

Microbially induced calcium carbonate precipitation (CCP) is a long-standing but re-emerging environmental engineering process for production of self-healing concrete, bioremediation, and long-term storage of CO2. CCP-capable bacteria, two Bacillus strains (JH3 and JH7) and one Sporosarcina strain (HYO08), were isolated from two samples of concrete and characterized phylogenetically. Calcium carbonate crystals precipitated by the three strains were morphologically distinct according to field emission scanning electron microscopy. Energy dispersive X-ray spectrometry mapping confirmed biomineralization via extracellular calcium carbonate production. The three strains differed in their physiological characteristics: growth at alkali pH and high NaCl concentrations, and urease activity. Sporosarcina sp. HYO08 and Bacillus sp. JH7 were more alkali- and halotolerant, respectively. Analysis of the community from the same concrete samples using barcoded pyrosequencing revealed that the relative abundance of Bacillus and Sporosarcina species was low, which indicated low culturability of other dominant bacteria. This study suggests that calcium carbonate crystals with different properties can be produced by various CCP-capable strains, and other novel isolates await discovery.

Advances in the field of high‐molecular‐weight polycyclic aromatic hydrocarbon biodegradation by bacteria

PubMed Central

Kanaly, Robert A.; Harayama, Shigeaki

2010-01-01

Summary Interest in understanding prokaryotic biotransformation of high‐molecular‐weight polycyclic aromatic hydrocarbons (HMW PAHs) has continued to grow and the scientific literature shows that studies in this field are originating from research groups from many different locations throughout the world. In the last 10 years, research in regard to HMW PAH biodegradation by bacteria has been further advanced through the documentation of new isolates that represent diverse bacterial types that have been isolated from different environments and that possess different metabolic capabilities. This has occurred in addition to the continuation of in‐depth comprehensive characterizations of previously isolated organisms, such as Mycobacterium vanbaalenii PYR‐1. New metabolites derived from prokaryotic biodegradation of four‐ and five‐ring PAHs have been characterized, our knowledge of the enzymes involved in these transformations has been advanced and HMW PAH biodegradation pathways have been further developed, expanded upon and refined. At the same time, investigation of prokaryotic consortia has furthered our understanding of the capabilities of microorganisms functioning as communities during HMW PAH biodegradation. PMID:21255317

Occurrence, diversity and community structure of culturable atrazine degraders in industrial and agricultural soils exposed to the herbicide in Shandong Province, P.R. China.

PubMed

Bazhanov, Dmitry P; Li, Chengyun; Li, Hongmei; Li, Jishun; Zhang, Xinjian; Chen, Xiangfeng; Yang, Hetong

2016-11-08

Soil populations of bacteria rapidly degrading atrazine are critical to the environmental fate of the herbicide. An enrichment bias from the routine isolation procedure prevents studying the diversity of atrazine degraders. In the present work, we analyzed the occurrence, diversity and community structure of soil atrazine-degrading bacteria based on their direct isolation. Atrazine-degrading bacteria were isolated by direct plating on a specially developed SM agar. The atrazine degradation genes trzN and atzABC were detected by multiplex PCR. The diversity of atrazine degraders was characterized by enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) genotyping followed by 16S rRNA gene phylogenetic analysis. The occurrence of atrazine-degrading bacteria was also assessed by conventional PCR targeting trzN and atzABC in soil DNA. A total of 116 atrazine-degrading isolates were recovered from bulk and rhizosphere soils sampled near an atrazine factory and from geographically distant maize fields. Fifteen genotypes were distinguished among 56 industrial isolates, with 13 of them representing eight phylogenetic groups of the genus Arthrobacter. The remaining two were closely related to Pseudomonas alcaliphila and Gulosibacter molinativorax and constituted major components of the atrazine-degrading community in the most heavily contaminated industrial plantless soil. All isolates from the adjacent sites inhabited by cogon grass or common reed were various Arthrobacter spp. with a strong prevalence of A. aurescens group. Only three genotypes were distinguished among 60 agricultural strains. Genetically similar Arthrobacter ureafaciens bacteria which occurred as minor inhabitants of cogon grass roots in the industrial soil were ubiquitous and predominant atrazine degraders in the maize rhizosphere. The other two genotypes represented two distant Nocardioides spp. that were specific to their geographic origins. Direct plating on SM agar enabled rapid isolation of atrazine-degrading bacteria and analysis of their natural diversity in soil. The results obtained provided evidence that contaminated soils harbored communities of genetically distinct bacteria capable of individually degrading and utilizing atrazine. The community structures of culturable atrazine degraders were habitat-specific. Bacteria belonging to the genus Arthrobacter were the predominant degraders of atrazine in the plant rhizosphere.

Genome Sequences for Six Rhodanobacter Strains, Isolated from Soils and the Terrestrial Subsurface, with Variable Denitrification Capabilities

PubMed Central

Green, Stefan J.; Rishishwar, Lavanya; Prakash, Om; Katz, Lee S.; Mariño-Ramírez, Leonardo; Jordan, I. King; Munk, Christine; Ivanova, Natalia; Mikhailova, Natalia; Watson, David B.; Brown, Steven D.; Palumbo, Anthony V.; Brooks, Scott C.

2012-01-01

We report the first genome sequences for six strains of Rhodanobacter species isolated from a variety of soil and subsurface environments. Three of these strains are capable of complete denitrification and three others are not. However, all six strains contain most of the genes required for the respiration of nitrate to gaseous nitrogen. The nondenitrifying members of the genus lack only the gene for nitrate reduction, the first step in the full denitrification pathway. The data suggest that the environmental role of bacteria from the genus Rhodanobacter should be reevaluated. PMID:22843592

Pattern of elemental release during the granite dissolution can be changed by aerobic heterotrophic bacterial strains isolated from Damma Glacier (central Alps) deglaciated granite sand.

PubMed

Lapanje, Aleš; Wimmersberger, Celine; Furrer, Gerhard; Brunner, Ivano; Frey, Beat

2012-05-01

Colonisation and weathering of freshly deglaciated granite are key processes in initial soil formation and development. We have obtained 438 isolates from granite sand covering glacial toe, 284 isolates at 22°C and 154 at 4°C incubation temperatures, respectively, to obtain cultures for the investigation of their weathering capabilities under laboratory conditions. The isolation of bacteria from granite sand was performed on rich-, intermediate- and low-nutrient-content solid media. Isolates were identified by 16S rRNA gene sequencing. According to the genera-associated weathering capabilities described in the literature and according to their abundance in our culture collection, we selected eight strains to analyse their effects on the weathering dynamics of granite sand during the batch culture experiment. Analysis of culturable bacteria showed higher species richness among isolates from 22°C than from 4°C incubations. In the R2A and 1/100 Ravan media, we observed the highest species richness of isolates obtained at 22°C and 4°C incubation temperatures, respectively. The obtained 16S rRNA sequences revealed the presence of alpha-, beta- and gamma-proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes. The most numerous group of isolates was distantly related to Collimonas representatives, and according to the sequences of the 16S rRNA genes, they can form a new genus. Isolates from this group had the capability of causing increased dissolution rates for Fe, W, Ni and Rb. In general, at each sampling during the 30-day experiment, every strain showed a unique weathering profile resulting from differential rates of the dissolution and the precipitation of different minerals in the batch culture. Consequently, the presence of different strains, their growth stage and changes in proportions of strains in the bacterial community can affect further soil development and the successive colonisation by plants.

Isolation and characterization of metal-reducing thermoanaerobacter strains from deep subsurface environments of the Piceance Basin, Colorado.

PubMed

Roh, Yul; Liu, Shi V; Li, Guangshan; Huang, Heshu; Phelps, Tommy J; Zhou, Jizhong

2002-12-01

Five bacterial strains were isolated from anaerobic enrichment cultures that had originated from inoculations with samples collected from the deep subsurface environments of the millions-of-years-old, geologically and hydrologically isolated Piceance Basin in Colorado. Small-subunit rRNA gene-based analyses indicated that all of these bacteria were closely related to Thermoanaerobacter ethanolicus, with similarities of 99.4 to 99.5%. Three isolates (X513, X514, and X561) from the five bacterial strains were used to examine physiological characteristics. These thermophilic bacteria were able to use acetate, glucose, hydrogen, lactate, pyruvate, succinate, and xylose as electron donors while reducing Fe(III), cobalt(III), chromium(VI), manganese(IV), and uranium(VI) at 60 degrees C. One of the isolates (X514) was also able to utilize hydrogen as an electron donor for Fe(III) reduction. These bacteria exhibited diverse mineral precipitation capabilities, including the formation of magnetite (Fe(3)O(4)), siderite (FeCO(3)), rhodochrosite (MnCO(3)), and uraninite (UO(2)). The gas composition of the incubation headspace and the ionic composition of the incubation medium exerted profound influences on the types of minerals formed. The susceptibility of the thermophilic Fe(III)-reducing cultures to metabolic inhibitors specific for ferric reductase, hydrogenase, and electron transport indicated that iron reduction by these bacteria is an enzymatic process.

Characterization of unusual bacteria isolated from respiratory secretions of cystic fibrosis patients and description of Inquilinus limosus gen. nov., sp. nov.

PubMed

Coenye, Tom; Goris, Johan; Spilker, Theodore; Vandamme, Peter; LiPuma, John J

2002-06-01

Using a polyphasic approach (including cellular protein and fatty acid analysis, biochemical characterization, 16S ribosomal DNA sequencing, and DNA-DNA hybridizations), we characterized 51 bacterial isolates recovered from respiratory secretions of cystic fibrosis (CF) patients. Our analyses showed that 24 isolates belong to taxa that have so far not (or only rarely) been reported from CF patients. These taxa include Acinetobacter sp., Bordetella hinzii, Burkholderia fungorum, Comamonas testosteroni, Chryseobacterium sp., Herbaspirillum sp., Moraxella osloensis, Pandoraea genomospecies 4, Ralstonia gilardii, Ralstonia mannitolilytica, Rhizobium radiobacter, and Xanthomonas sp. In addition, one isolate most likely represents a novel Ralstonia species, whereas nine isolates belong to novel taxa within the alpha-PROTEOBACTERIA: Eight of these latter isolates are classified into the novel genus Inquilinus gen. nov. as Inquilinus limosus gen. nov., sp. nov., or as Inquilinus sp. The remaining 17 isolates are characterized as members of the family ENTEROBACTERIACEAE: The recovery of these species suggests that the CF lung is an ecological niche capable of supporting the growth of a wide variety of bacteria rarely seen in clinical samples. Elucidation of the factors that account for the association between these unusual species and the respiratory tract of CF patients may provide important insights into the pathophysiology of CF infection. Because accurate identification of these organisms in the clinical microbiology laboratory may be problematic, the present study highlights the utility of reference laboratories capable of identifying unusual species recovered from CF sputum.

Isolation and identification of culturable bacteria, capable of heterotrophic growth, from rapid sand filters of drinking water treatment plants.

PubMed

Vandermaesen, Johanna; Lievens, Bart; Springael, Dirk

The microbial community in sand filters (SFs) of drinking water treatment plants (DWTPs) likely contributes to SF functionalities, such as organic carbon removal through heterotrophic metabolism. However, the dynamics and functionality of the SF microbiome and microbial communities in oligotrophic freshwater environments in general, are poorly understood. Therefore, the availability of bacterial strains from these oligotrophic environments is of great interest, but such organisms are currently underrepresented in culture collections. Focusing on heterotrophic carbon metabolism, bacteria were isolated from SFs using conventional media and media that contained SF extracts to mimic the SF environment. The majority of isolates belonged to Betaproteobacteria, more specifically to the families Comamonadaceae (genera Acidovorax, Curvibacter, Hydrogenophaga, Simplicispira, Paucibacter, Pelomonas, Piscinibacter and Rhodoferax) and Oxalobacteraceae (Undibacterium). Additionally, members of Alphaproteobacteria (Mesorhizobium), Gammaproteobacteria (Aeromonas and Perlucidibaca) and Actinobacteria (Rhodococcus and Brachybacterium) were isolated. Several of those genera have only rarely been described, but appear typical inhabitants of oligotrophic freshwater environments. In this regard, the Comamonadaceae isolates are of particular interest. Our study shows that bacteria representative of oligotrophic environments can be isolated using simple isolation procedures. The isolates provide a microbial framework for extending our knowledge of the taxonomy, physiology and functionality of oligotrophic freshwater microbiomes and their interactions with possible invaders. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

No evidential correlation between veterinary antibiotic degradation ability and resistance genes in microorganisms during the biodegradation of doxycycline.

PubMed

Wen, Xin; Wang, Yan; Zou, Yongde; Ma, Baohua; Wu, Yinbao

2018-01-01

Biodegradation of antibiotic residues in the environment by microorganisms may lead to the generation of antibiotic resistance genes (ARGs), which are of great concern to human health. The aim of this study was to determine whether there is a relationship between the ability to degrade antibiotic doxycycline (DOX) and the development of resistance genes in microorganisms. We isolated and identified ten bacterial strains from a vegetable field that had received long-term manure application as fertilizer and were capable of surviving in a series of DOX concentrations (25, 50, 80, and 100mg/L). Our results showed no evidential correlation between DOX degradation ability and the development of resistance genes among the isolated microorganisms that had high DOX degradation capability (P > 0.05). This was based on the fact that Escherichia sp. and Candida sp. were the most efficient bacterial strains to degrade DOX (92.52% and 91.63%, respectively), but their tetracycline resistance genes showed a relatively low risk of antibiotic resistance in a 7-day experiment. Moreover, the tetM of the ribosomal protection protein genes carried by these two preponderant bacteria was five-fold higher than that carried by other isolates (P < 0.05). Pearson correlations between the C t /C 0 of DOX and tet resistance genes of three isolates, except for Escherichia sp. and Candida sp., showed remarkable negative correlations (P < 0.05), mainly because tetG markedly increased during the DOX degradation process. Our results concluded that the biodegradation of antibiotic residues may not necessarily lead to the development of ARGs in the environment. In addition, the two bacteria that we isolated, namely, Escherichia sp. and Candida sp., are potential candidates for the engineering of environmentally friendly bacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

Gram-positive marine bacteria as a potential resource for the discovery of quorum sensing inhibitors.

PubMed

Teasdale, Margaret E; Donovan, Kellye A; Forschner-Dancause, Stephanie R; Rowley, David C

2011-08-01

Inhibitors of bacterial quorum sensing have been proposed as potentially novel therapeutics for the treatment of certain bacterial diseases. We recently reported a marine Halobacillus salinus isolate that secretes secondary metabolites capable of quenching quorum sensing phenotypes in several Gram-negative reporter strains. To investigate how widespread the production of such compounds may be in the marine bacterial environment, 332 Gram-positive isolates from diverse habitats were tested for their ability to interfere with Vibrio harveyi bioluminescence, a cell signaling-regulated phenotype. Rapid assay methods were employed where environmental isolates were propagated alongside the reporter strain. "Actives" were defined as bacteria that interfered with bioluminescence without visible cell-killing effects (antibiotic activity). A total of 49 bacterial isolates interfered with bioluminescence production in the assays. Metabolite extracts were generated from cultures of the active isolates, and 28 reproduced the bioluminescence inhibition against V. harveyi. Of those 28, five extracts additionally inhibited violacein production by Chromobacterium violaceum. Chemical investigations revealed that phenethylamides and a cyclic dipeptide are two types of secondary metabolites responsible for the observed activities. The active bacterial isolates belonged primarily to either the genus Bacillus or Halobacillus. The results suggest that Gram-positive marine bacteria are worthy of further investigation for the discovery of quorum sensing antagonists.

Microbial population dynamics in the sediments of a eutrophic lake (Aydat, France) and characterization of some heterotrophic bacterial isolates.

PubMed

Mallet, C; Basset, M; Fonty, G; Desvilettes, C; Bourdier, G; Debroas, D

2004-07-01

The bacterial populations of anoxic sediments in a eutrophic lake (Aydat, Puy-de-Dôme-France) were studied by phospholipid fatty acid analysis (PLFA) and also by culturing heterotrophic bacteria under strictly anaerobic conditions. The mean PLFA concentrations of prokaryotes and microeukaryotes were 5.7 +/- 2.9 mgC g(-1) DS and 9.6 +/- 6.7 mgC g(-1) DS, respectively. The analysis of bacterial PLFA markers was used to determine the dynamics of the Gram-positive and Gram-negative species of anaerobic bacteria, Clostridiae, and sulfate-reducing bacteria. Throughout the sampling period the concentrations of i15:0 (from 20 nmol g(-1) DS to 130 nmol g(-1) DS), markers of Gram-positive bacteria, were higher than those for Gram-negative bacteria. The dynamics of Clostridiae (Cy15:0) paralleled those of sulfate-reducing bacteria that were marked by i17:1omega7. Partial 16S rDNA sequencing and the physiological study of the various fermenting strains, whose abundance in the superficial sediment layer was 1.1 +/- 0.4 x 10(6) cells mL(-1), showed that all the isolates belonged to the Clostridiae and related taxa ( Lactosphaera pasteurii, Clostridium vincentii, C. butyricum, C. algidixylanolyticum, C. puniceum, C. lituseburense, and C. gasigenes). All the isolates were capable of metabolizing a wide range of organic substrates.

University of South Carolina Aiken Biofuels Laboratory in Aiken, SC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Garriet W.; Piskorska, Magdalena

2014-10-30

Biological production of hydrogen has been investigated over the past 30 years with the ultimate goal of providing a clean, carbon-neutral fuel. However, based on an extensive literature search and the recommendations of several recent DOE- and DOD-sponsored expert review panels it is obvious that an important element of this research has been largely overlooked - the physiology and diversity of naturally occurring, H2-producing bacteria. The main objective of this project was to develop a technique to extensively screen nitrogen fixing bacteria isolated from unique environments suspected of H2 production. Those showing H2-producing activity were tested on latex based mats,more » which could provide active centers of fuel cells. Specific objectives of the project were to establish a biofuels laboratory at the Aiken County Center for Hydrogen Research, where the following activities were persued.1) Develop a semi-automated apparatus to screen hundreds of bacteria in a short time; 2) Identify bacteria capable of producing hydrogen at rates sufficiently high to power a fuel cell. 3) Embed specific bacteria with high hydrogen production potentials into latex mats that can be incorporated in fuel cells applicable to a variety of industrial settings. During this project we developed screening techniques which include colorimetric and gas chromatographic assays for hydrogen production by bacterial isolates. Isolates were characterized both metabolically and genetically and preserved for future use. Isolates found to produce significant amounts of hydrogen were screened for activity under various environments. Potential isolates were then embedded in latex coatings and assayed for hydrogen production under different environmental conditions« less

University of South Carolina Aiken Biofuels Laboratory in Aiken, SC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Garriet W.

Biological production of hydrogen has been investigated over the past 30 years with the ultimate goal of providing a clean, carbon-neutral fuel. However, based on an extensive literature search and the recommendations of several recent DOE- and DOD-sponsored expert review panels it is obvious that an important element of this research has been largely overlooked - the physiology and diversity of naturally occurring, H2-producing bacteria. The main objective of this project was to develop a technique to extensively screen nitrogen fixing bacteria isolated from unique environments suspected of H2 production. Those showing H2-producing activity were tested on latex based mats,more » which could provide active centers of fuel cells. Specific objectives of the project were to establish a biofuels laboratory at the Aiken County Center for Hydrogen Research, where the following activities were persued.1) Develop a semi-automated apparatus to screen hundreds of bacteria in a short time; 2) Identify bacteria capable of producing hydrogen at rates sufficiently high to power a fuel cell. 3) Embed specific bacteria with high hydrogen production potentials into latex mats that can be incorporated in fuel cells applicable to a variety of industrial settings. During this project we developed screening techniques which include colorimetric and gas chromatographic assays for hydrogen production by bacterial isolates. Isolates were characterized both metabolically and genetically and preserved for future use. Isolates found to produce significant amounts of hydrogen were screened for activity under various environments. Potential isolates were then embedded in latex coatings and assayed for hydrogen production under different environmental conditions« less

Psychrophilic Microorganisms from Areas Associated with the Viking Spacecraft

PubMed Central

Foster, Terry L.; Winans, Luther

1975-01-01

Microorganisms capable of growth at 7 C were enumerated and isolated from soil samples from the manufacture and assembly areas of the Viking spacecraft. Populations ranging from 4.2 × 103 to 7.7 × 106/g of soil were isolated from the 15 soil samples examined. Temperature requirements were determined, and those growing at 3 C, but not at 32 C, were designated as obligate psychrophiles in this investigation. Populations of soil bacteria, including aerobic sporeformers, ranging from 1.5 × 102 to 9.8 × 105/g were capable of growth at 3 C, but not at 32 C. Bacterial isolates were identified to major generic groups. No psychrophilic sporeformers were isolated from soil from the manufacture area, but psychrophilic sporeformers ranged from 0 to 6.1 × 103/g from soil from the assembly area. PMID:1190759

Polyhydroxyalkanoate production potential of heterotrophic bacteria in activated sludge.

PubMed

Inoue, Daisuke; Suzuki, Yuta; Uchida, Takahiro; Morohoshi, Jota; Sei, Kazunari

2016-01-01

This study was conducted to evaluate the polyhydroxyalkanoate (PHA) production potential of cultivable heterotrophic bacteria in activated sludge by genotypic and phenotypic characterizations. A total of 114 bacterial strains were isolated from four activated sludge samples taken from a lab-scale sequencing batch reactor and three wastewater treatment processes of two municipal wastewater treatment plants. PCR detection of the phaC genes encoding class I and II PHA synthase revealed that 15% of the total isolates possessed phaC genes, all of which had the closest similarities to known phaC genes of α- and β-Proteobacteria and Actinobacteria. PHA production experiments under aerobic and nitrogen-limited conditions showed that 68% of the total isolates were capable of producing PHA from at least one of the six substrates used (acetate, propionate, lactate, butyrate, glucose and glycerol). Genotypic and phenotypic characterizations revealed that 75% of the activated sludge bacteria had PHA production potential. Our results also indicated that short-chain fatty acids would be the preferable substrates for PHA production by activated sludge bacteria, and that there might be a variety of unidentified phaC genes in activated sludge. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Evidence for colonization and destruction of hinge ligaments in cultured juvenile Pacific oysters (Crassostrea gigas) by cytophaga-like bacteria.

PubMed Central

Dungan, C F; Elston, R A; Schiewe, M H

1989-01-01

Several strains of cytophaga-like gliding bacteria (CLB) were isolated as numerically dominant or codominant components of bacterial populations associated with proteinaceous hinge ligaments of cultured juvenile Pacific oysters, Crassostrea gigas. These bacteria were morphologically similar to long, flexible bacilli occurring within degenerative lesions in oyster hinge ligaments. Among bacteria isolated from hinge ligaments, only CLB strains were capable of sustained growth with hinge ligament matrix as the sole source of organic carbon and nitrogen. In vitro incubation of cuboidal portions of ligament resilium with ligament CLB resulted in bacterial proliferation on the surfaces and penetration deep into ligament matrices. Bacterial proliferation was accompanied by loss of resilium structural and mechanical integrity, including complete liquefaction, at incubation temperatures between 10 and 20 degrees C. The morphological, distributional, and degradative characteristics of CLB isolated from oyster hinge ligaments provide compelling, albeit indirect, evidence that CLB are the agents of a degenerative disease affecting juvenile cultured oysters. The motility, metabolic, and hydrolytic characteristics of hinge ligament CLB and the low moles percent G + C values (32.4 to 32.9) determined for three representative strains indicate that they are marine Cytophaga spp. Images PMID:2757377

Evidence for colonization and destruction of hinge ligaments in cultured juvenile Pacific oysters (Crassostrea gigas) by cytophaga-like bacteria.

PubMed

Dungan, C F; Elston, R A; Schiewe, M H

1989-05-01

Several strains of cytophaga-like gliding bacteria (CLB) were isolated as numerically dominant or codominant components of bacterial populations associated with proteinaceous hinge ligaments of cultured juvenile Pacific oysters, Crassostrea gigas. These bacteria were morphologically similar to long, flexible bacilli occurring within degenerative lesions in oyster hinge ligaments. Among bacteria isolated from hinge ligaments, only CLB strains were capable of sustained growth with hinge ligament matrix as the sole source of organic carbon and nitrogen. In vitro incubation of cuboidal portions of ligament resilium with ligament CLB resulted in bacterial proliferation on the surfaces and penetration deep into ligament matrices. Bacterial proliferation was accompanied by loss of resilium structural and mechanical integrity, including complete liquefaction, at incubation temperatures between 10 and 20 degrees C. The morphological, distributional, and degradative characteristics of CLB isolated from oyster hinge ligaments provide compelling, albeit indirect, evidence that CLB are the agents of a degenerative disease affecting juvenile cultured oysters. The motility, metabolic, and hydrolytic characteristics of hinge ligament CLB and the low moles percent G + C values (32.4 to 32.9) determined for three representative strains indicate that they are marine Cytophaga spp.

Antimicrobial Properties of Garlic Oil against Human Enteric Bacteria: Evaluation of Methodologies and Comparisons with Garlic Oil Sulfides and Garlic Powder

PubMed Central

Ross, Z. M.; O'Gara, E. A.; Hill, D. J.; Sleightholme, H. V.; Maslin, D. J.

2001-01-01

The antimicrobial effects of aqueous garlic extracts are well established but those of garlic oil (GO) are little known. Methodologies for estimating the antimicrobial activity of GO were assessed and GO, GO sulfide constituents, and garlic powder (GP) were compared in tests against human enteric bacteria. Test methodologies were identified as capable of producing underestimates of GO activity. Antimicrobial activity was greater in media lacking tryptone or cysteine, suggesting that, as for allicin, GO effects may involve sulfhydryl reactivity. All bacteria tested, which included both gram-negative and -positive bacteria and pathogenic forms, were susceptible to garlic materials. On a weight-of-product basis, 24 h MICs for GO (0.02 to 5.5 mg/ml, 62 enteric isolates) and dimethyl trisulfide (0.02 to 0.31 mg/ml, 6 enteric isolates) were lower than those for a mixture of diallyl sulfides (0.63 to 25 mg/ml, 6 enteric isolates) and for GP, which also exhibited a smaller MIC range (6.25 to 12.5 mg/ml, 29 enteric isolates). Viability time studies of GO and GP against Enterobacter aerogenes showed time- and dose-dependent effects. Based upon its thiosulfinate content, GP was more active than GO against most bacteria, although some properties of GO are identified as offering greater therapeutic potential. Further exploration of the potential of GP and GO in enteric disease control appears warranted. PMID:11133485

Novel components of leaf bacterial communities of field-grown tomato plants and their potential for plant growth promotion and biocontrol of tomato diseases.

PubMed

Romero, Fernando M; Marina, María; Pieckenstain, Fernando L

2016-04-01

This work aimed to characterize potentially endophytic culturable bacteria from leaves of cultivated tomato and analyze their potential for growth promotion and biocontrol of diseases caused by Botrytis cinerea and Pseudomonas syringae. Bacteria were obtained from inner tissues of surface-disinfected tomato leaves of field-grown plants. Analysis of 16S rRNA gene sequences identified bacterial isolates related to Exiguobacterium aurantiacum (isolates BT3 and MT8), Exiguobacterium spp. (isolate GT4), Staphylococcus xylosus (isolate BT5), Pantoea eucalypti (isolate NT6), Bacillus methylotrophicus (isolate MT3), Pseudomonas veronii (isolates BT4 and NT2), Pseudomonas rhodesiae (isolate BT2) and Pseudomonas cichorii (isolate NT3). After seed inoculation, BT2, BT4, MT3, MT8, NT2 and NT6 were re-isolated from leaf extracts. NT2, BT2, MT3 and NT6 inhibited growth of Botrytis cinerea and Pseudomonas syringae pv. tomato in vitro, produced antimicrobial compounds and reduced leaf damage caused by B. cinerea. Some of these isolates also promoted growth of tomato plants, produced siderophores, the auxin indole-3-acetic and solubilized inorganic phosphate. Thus, bacterial communities of leaves from field-grown tomato plants were found to harbor potentially endophytic culturable beneficial bacteria capable of antagonizing pathogenic microorganisms and promoting plant growth, which could be used as biological control agents and biofertilizers/biostimulators for promotion of tomato plant growth. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Biodegradation of carbofuran in soils within Nzoia River Basin, Kenya.

PubMed

Onunga, Daniel O; Kowino, Isaac O; Ngigi, Anastasiah N; Osogo, Aggrey; Orata, Francis; Getenga, Zachary M; Were, Hassan

2015-01-01

Carbofuran (2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate) has been used within the Nzoia River Basin (NRB), especially in Bunyala Rice Irrigation Schemes, in Kenya for the control of pests. In this study, the capacity of native bacteria to degrade carbofuran in soils from NRB was investigated. A gram positive, rod-shaped bacteria capable of degrading carbofuran was isolated through liquid cultures with carbofuran as the only carbon and nitrogen source. The isolate degraded 98% of 100-μg mL(-1) carbofuran within 10 days with the formation of carbofuran phenol as the only detectable metabolite. The degradation of carbofuran was followed by measuring its residues in liquid cultures using high performance liquid chromatography (HPLC). Physical and morphological characteristics as well as molecular characterization confirmed the bacterial isolate to be a member of Bacillus species. The results indicate that this strain of Bacillus sp. could be considered as Bacillus cereus or Bacillus thuringiensis with a bootstrap value of 100% similar to the 16S rRNA gene sequences. The biodegradation capability of the native strains in this study indicates that they have great potential for application in bioremediation of carbofuran-contaminated soil sites.

Coexisting bacterial populations responsible for multiphasic mineralization kinetics in soil. [Janthinobacterium sp. Rhodococcus sp

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidt, S.K.; Gier, M.J.

1990-09-01

Experiments were conducted to study populations of indigenous microorganisms capable of mineralizing 2,4-dinitrophenol (DNP) in two soils. Previous kinetic analyses indicated the presence of two coexisting populations of DNP-mineralizing microorganisms in a forest soil (soil 1). Studies in which eucaryotic and procaryotic inhibitors were added to this soil indicated that both populations were bacterial. Most-probable-number counts with media containing different concentrations of DNP indicated that more bacteria could mineralize low concentrations of DNP than could metabolize high concentrations of it. Enrichments with varying concentrations of DNP and various combinations of inhibitors consistently resulted in the isolation of the same twomore » species of bacteria from soil 1. This soil contained a large number and variety of fungi, but no fungi capable of mineralizing DNP were isolated. The two bacterial isolates were identified as a Janthinobacterium sp. and a Rhodococcus sp. The Janthinobacterium sp. had a low {mu}{sub max} and a low K{sub m} for DNP mineralization, whereas the Rhodococcus sp. had much higher values for both parameters. These differences between the two species of bacteria were similar to differences seen when soil was incubated with different concentrations of DNP. Values for {mu}{sub max} from soil incubations were similar to {mu}{sub max} values obtained in pure culture studies. In contrast, K{sub s} and K{sub m} values showed greater variation between soil and pure culture studies.« less

Removal of methylmercury and tributyltin (TBT) using marine microorganisms.

PubMed

Lee, Seong Eon; Chung, Jin Wook; Won, Ho Shik; Lee, Dong Sup; Lee, Yong-Woo

2012-02-01

Two marine species of bacteria were isolated that are capable of degrading organometallic contaminants: Pseudomonas balearica, which decomposes methylmercury; and Shewanella putrefaciens, which decomposes tributyltin. P. balearica decomposed 97% of methylmercury (20.0 μg/L) into inorganic mercury after 3 h, while S. putrefaciens decomposed 88% of tributyltin (55.3 μg Sn/L) in real wastewater after 36 h. These data indicate that the two bacteria efficiently decomposed the targeted substances and may be applied to real wastewater.

Microbiota from Rhabditis regina may alter nematode entomopathogenicity.

PubMed

Jiménez-Cortés, Jesús Guillermo; Canales-Lazcano, Jorge; Lara-Reyes, Nancy; Rosenblueth, Mónica; Martínez-Romero, Esperanza; Contreras-Garduño, Jorge

2016-11-01

Here we report the presence of the entomopathogenic nematode Rhabditis (Rhabditoides) regina affecting white grubs (Phyllophaga sp. and Anomala sp.) in Mexico and R. regina-associated bacteria. Bioassays were performed to test the entomopathogenic capacity of dauer and L2 and L3 (combined) larval stages. Furthermore, we determined the diversity of bacteria from laboratory nematodes cultivated for 2 years (dauer and L2-L3 larvae) and from field nematodes (dauer and L2-L3 larvae) in addition to the virulence in Galleria mellonella larvae of some bacterial species from both laboratory and field nematodes. Dauer and non-dauer larvae of R. regina killed G. mellonella. Bacteria such as Serratia sp. (isolated from field nematodes) and Klebsiella sp. (isolated from larvae of laboratory and field nematodes) may explain R. regina entomopathogenic capabilities. Different bacteria were found in nematodes after subculturing in the laboratory suggesting that R. regina may acquire bacteria in different environments. However, there were some consistently found bacteria from laboratory and field nematodes such as Pseudochrobactrum sp., Comamonas sp., Alcaligenes sp., Klebsiella sp., Acinetobacter sp., and Leucobacter sp. that may constitute the nematode microbiome. Results showed that some bacteria contributing to entomopathogenicity may be lost in the laboratory representing a disadvantage when nematodes are cultivated to be used for biological control.

Bacteria associated with oak and ash on a TCE-contaminated site: characterization of isolates with potential to avoid evapotranspiration of TCE.

PubMed

Weyens, Nele; Taghavi, Safiyh; Barac, Tanja; van der Lelie, Daniel; Boulet, Jana; Artois, Tom; Carleer, Robert; Vangronsveld, Jaco

2009-11-01

Along transects under a mixed woodland of English Oak (Quercus robur) and Common Ash (Fraxinus excelsior) growing on a trichloroethylene (TCE)-contaminated groundwater plume, sharp decreases in TCE concentrations were observed, while transects outside the planted area did not show this remarkable decrease. This suggested a possibly active role of the trees and their associated bacteria in the remediation process. Therefore, the cultivable bacterial communities associated with both tree species growing on this TCE-contaminated groundwater plume were investigated in order to assess the possibilities and practical aspects of using these common native tree species and their associated bacteria for phytoremediation. In this study, only the cultivable bacteria were characterized because the final aim was to isolate TCE-degrading, heavy metal resistant bacteria that might be used as traceable inocula to enhance bioremediation. Cultivable bacteria isolated from bulk soil, rhizosphere, root, stem, and leaf were genotypically characterized by amplified rDNA restriction analysis (ARDRA) of their 16S rRNA gene and identified by 16S rRNA gene sequencing. Bacteria that displayed distinct ARDRA patterns were screened for heavy metal resistance, as well as TCE tolerance and degradation, as preparation for possible future in situ inoculation experiments. Furthermore, in situ evapotranspiration measurements were performed to investigate if the degradation capacity of the associated bacteria is enough to prevent TCE evapotranspiration to the air. Between both tree species, the associated populations of cultivable bacteria clearly differed in composition. In English Oak, more species-specific, most likely obligate endophytes were found. The majority of the isolated bacteria showed increased tolerance to TCE, and TCE degradation capacity was observed in some of the strains. However, in situ evapotranspiration measurements revealed that a significant amount of TCE and its metabolites was evaporating through the leaves to the atmosphere. The characterization of the isolates obtained in this study shows that the bacterial community associated with Oak and Ash on a TCE-contaminated site, was strongly enriched with TCE-tolerant strains. However, this was not sufficient to degrade all TCE before it reaches the leaves. A possible strategy to overcome this evapotranspiration to the atmosphere is to enrich the plant-associated TCE-degrading bacteria by in situ inoculation with endophytic strains capable of degrading TCE.

Bacteria associated with oak and ash on a TCE-contaminated site: Characterization of isolates with potential to avoid evapotranspiration of TCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weyens, N.; van der Lelie, D.; Taghavi, S.

2009-11-01

Along transects under a mixed woodland of English Oak (Quercus robur) and Common Ash (Fraxinus excelsior) growing on a trichloroethylene (TCE)-contaminated groundwater plume, sharp decreases in TCE concentrations were observed, while transects outside the planted area did not show this remarkable decrease. This suggested a possibly active role of the trees and their associated bacteria in the remediation process. Therefore, the cultivable bacterial communities associated with both tree species growing on this TCE-contaminated groundwater plume were investigated in order to assess the possibilities and practical aspects of using these common native tree species and their associated bacteria for phytoremediation. Inmore » this study, only the cultivable bacteria were characterized because the final aim was to isolate TCE-degrading, heavy metal resistant bacteria that might be used as traceable inocula to enhance bioremediation. Cultivable bacteria isolated from bulk soil, rhizosphere, root, stem, and leaf were genotypically characterized by amplified rDNA restriction analysis (ARDRA) of their 16S rRNA gene and identified by 16S rRNA gene sequencing. Bacteria that displayed distinct ARDRA patterns were screened for heavy metal resistance, as well as TCE tolerance and degradation, as preparation for possible future in situ inoculation experiments. Furthermore, in situ evapotranspiration measurements were performed to investigate if the degradation capacity of the associated bacteria is enough to prevent TCE evapotranspiration to the air. Between both tree species, the associated populations of cultivable bacteria clearly differed in composition. In English Oak, more species-specific, most likely obligate endophytes were found. The majority of the isolated bacteria showed increased tolerance to TCE, and TCE degradation capacity was observed in some of the strains. However, in situ evapotranspiration measurements revealed that a significant amount of TCE and its metabolites was evaporating through the leaves to the atmosphere. The characterization of the isolates obtained in this study shows that the bacterial community associated with Oak and Ash on a TCE-contaminated site, was strongly enriched with TCE-tolerant strains. However, this was not sufficient to degrade all TCE before it reaches the leaves. A possible strategy to overcome this evapotranspiration to the atmosphere is to enrich the plant-associated TCE-degrading bacteria by in situ inoculation with endophytic strains capable of degrading TCE.« less

Ammonia production by ruminal microorganisms and enumeration, isolation, and characterization of bacteria capable of growth on peptides and amino acids from the sheep rumen.

PubMed

Eschenlauer, S C P; McKain, N; Walker, N D; McEwan, N R; Newbold, C J; Wallace, R J

2002-10-01

Excessive NH(3) production in the rumen is a major nutritional inefficiency in ruminant animals. Experiments were undertaken to compare the rates of NH(3) production from different substrates in ruminal fluid in vitro and to assess the role of asaccharolytic bacteria in NH(3) production. Ruminal fluid was taken from four rumen-fistulated sheep receiving a mixed hay-concentrate diet. The calculated rate of NH(3) production from Trypticase varied from 1.8 to 19.7 nmol mg of protein(-1) min(-1) depending on the substrate, its concentration, and the method used. Monensin (5 micro M) inhibited NH(3) production from proteins, peptides, and amino acids by an average of 28% with substrate at 2 mg/ml, compared to 48% with substrate at 20 mg/ml (P = 0.011). Of the total bacterial population, 1.4% grew on Trypticase alone, of which 93% was eliminated by 5 micro M monensin. Many fewer bacteria (0.002% of the total) grew on amino acids alone. Nineteen isolates capable of growth on Trypticase were obtained from four sheep. 16S ribosomal DNA and traditional identification methods indicated the bacteria fell into six groups. All were sensitive to monensin, and all except one group (group III, similar to Atopobium minutum), produced NH(3) at >250 nmol min(-1) mg of protein(-1), depending on the medium, as determined by a batch culture method. All isolates had exopeptidase activity, but only group III had an apparent dipeptidyl peptidase I activity. Groups I, II, and IV were most closely related to asaccharolytic ruminal and oral Clostridium and Eubacterium spp. Group V comprised one isolate, similar to Desulfomonas piger (formerly Desulfovibrio pigra). Group VI was 95% similar to Acidaminococcus fermentans. Growth of the Atopobium- and Desulfomonas-like isolates was enhanced by sugars, while growth of groups I, II, and V was significantly depressed by sugars. This study therefore demonstrates that different methodologies and different substrate concentrations provide an explanation for different apparent rates of ruminal NH(3) production reported in different studies and identifies a diverse range of hyper-ammonia-producing bacteria in the rumen of sheep.

Ammonia Production by Ruminal Microorganisms and Enumeration, Isolation, and Characterization of Bacteria Capable of Growth on Peptides and Amino Acids from the Sheep Rumen

PubMed Central

Eschenlauer, S. C. P.; McKain, N.; Walker, N. D.; McEwan, N. R.; Newbold, C. J.; Wallace, R. J.

2002-01-01

Excessive NH3 production in the rumen is a major nutritional inefficiency in ruminant animals. Experiments were undertaken to compare the rates of NH3 production from different substrates in ruminal fluid in vitro and to assess the role of asaccharolytic bacteria in NH3 production. Ruminal fluid was taken from four rumen-fistulated sheep receiving a mixed hay-concentrate diet. The calculated rate of NH3 production from Trypticase varied from 1.8 to 19.7 nmol mg of protein−1 min−1 depending on the substrate, its concentration, and the method used. Monensin (5 μM) inhibited NH3 production from proteins, peptides, and amino acids by an average of 28% with substrate at 2 mg/ml, compared to 48% with substrate at 20 mg/ml (P = 0.011). Of the total bacterial population, 1.4% grew on Trypticase alone, of which 93% was eliminated by 5 μM monensin. Many fewer bacteria (0.002% of the total) grew on amino acids alone. Nineteen isolates capable of growth on Trypticase were obtained from four sheep. 16S ribosomal DNA and traditional identification methods indicated the bacteria fell into six groups. All were sensitive to monensin, and all except one group (group III, similar to Atopobium minutum), produced NH3 at >250 nmol min−1 mg of protein−1, depending on the medium, as determined by a batch culture method. All isolates had exopeptidase activity, but only group III had an apparent dipeptidyl peptidase I activity. Groups I, II, and IV were most closely related to asaccharolytic ruminal and oral Clostridium and Eubacterium spp. Group V comprised one isolate, similar to Desulfomonas piger (formerly Desulfovibrio pigra). Group VI was 95% similar to Acidaminococcus fermentans. Growth of the Atopobium- and Desulfomonas-like isolates was enhanced by sugars, while growth of groups I, II, and V was significantly depressed by sugars. This study therefore demonstrates that different methodologies and different substrate concentrations provide an explanation for different apparent rates of ruminal NH3 production reported in different studies and identifies a diverse range of hyper-ammonia-producing bacteria in the rumen of sheep. PMID:12324340

Phylogenentic and enzymatic characterization of psychrophilic and psychrotolerant marine bacteria belong to γ-Proteobacteria group isolated from the sub-Antarctic Beagle Channel, Argentina.

PubMed

Cristóbal, Héctor A; Benito, Juliana; Lovrich, Gustavo A; Abate, Carlos M

2015-05-01

The phylogenetic and physiological characteristics of cultivable-dependent approaches were determined to establish the diversity of marine bacteria associated with the intestines of benthonic organisms and seawater samples from the Argentina's Beagle Channel. A total of 737 isolates were classified as psychrophlic and psychrotolerant culturable marine bacteria. These cold-adapted microorganisms are capable of producing cold-active glycosyl hydrolases, such as β-glucosidases, celulases, β-galactosidases, xylanases, chitinases, and proteases. These enzymes could have potential biotechnological applications for use in low-temperature manufacturing processes. According to polymerase chain reaction-restriction fragment length polymorphism analysis of part of genes encoding 16S ribosomal DNA (ARDRA) and DNA gyrase subunit B (gyrB-RFLP), 11 operational taxonomic units (OTU) were identified and clustered in known genera using InfoStat software. The 50 isolates selected were sequenced based on near full sequence analysis of 16S rDNA and gyrB sequences and identified by their nearest neighbors ranging between 96 and 99 % of identities. Phylogenetic analyses using both genes allowed relationships between members of the cultured marine bacteria belonging to the γ-Proteobacteria group (Aeromonas, Halteromonas, Pseudomonas, Pseudoalteromonas, Shewanella, Serratia, Colwellia, Glacielocola, and Psychrobacter) to be evaluated. Our research reveals a high diversity of hydrolytic bacteria, and their products actuality has an industrial use in several bioprocesses at low-temperature manufacturing.

Production of a Pyrrole Antibiotic by a Marine Bacterium1

PubMed Central

Burkholder, Paul R.; Pfister, Robert M.; Leitz, Frederick H.

1966-01-01

Evidence is presented for the isolation and identification of bacteria able to synthesize an unusual antibiotic containing five bromine atoms per molecule. The identification and taxonomic position of these bacteria was made by use of a computer in conjunction with traditional methods. These microorganisms and closely related strains have been isolated on various occasions from tropical water in the vicinity of Puerto Rico. One bacterium, a pseudomonad, has been given the name Pseudomonas bromoutilis because of its distinctive capability. The antibiotic has been extracted, purified, and obtained in crystal form, and its structure has been determined. Although clinical tests of its properties were not encouraging, it may be of significant value and interest from an ecological standpoint. Images Fig. 1 PMID:4380876

Selection and Characterization of Biofuel-Producing Environmental Bacteria Isolated from Vegetable Oil-Rich Wastes

PubMed Central

Escobar-Niño, Almudena; Luna, Carlos; Luna, Diego; Marcos, Ana T.; Cánovas, David; Mellado, Encarnación

2014-01-01

Fossil fuels are consumed so rapidly that it is expected that the planet resources will be soon exhausted. Therefore, it is imperative to develop alternative and inexpensive new technologies to produce sustainable fuels, for example biodiesel. In addition to hydrolytic and esterification reactions, lipases are capable of performing transesterification reactions useful for the production of biodiesel. However selection of the lipases capable of performing transesterification reactions is not easy and consequently very few biodiesel producing lipases are currently available. In this work we first isolated 1,016 lipolytic microorganisms by a qualitative plate assay. In a second step, lipolytic bacteria were analyzed using a colorimetric assay to detect the transesterification activity. Thirty of the initial lipolytic strains were selected for further characterization. Phylogenetic analysis revealed that 23 of the bacterial isolates were Gram negative and 7 were Gram positive, belonging to different clades. Biofuel production was analyzed and quantified by gas chromatography and revealed that 5 of the isolates produced biofuel with yields higher than 80% at benchtop scale. Chemical and viscosity analysis of the produced biofuel revealed that it differed from biodiesel. This bacterial-derived biofuel does not require any further downstream processing and it can be used directly in engines. The freeze-dried bacterial culture supernatants could be used at least five times for biofuel production without diminishing their activity. Therefore, these 5 isolates represent excellent candidates for testing biofuel production at industrial scale. PMID:25099150

Investigation of reduction and tolerance capability of lactic acid bacteria isolated from kimchi against nitrate and nitrite in fermented sausage condition.

PubMed

Paik, Hyun-Dong; Lee, Joo-Yeon

2014-08-01

Lactobacillus brevis KGR3111, Lactobacillus curvatus KGR 2103, Lactobacillus plantarum KGR 5105, and Lactobacillus sakei KGR 4108 isolated from kimchi were investigated for their potential to be used as starter culture for fermented sausages with the capability to reduce and tolerate nitrate/nitrite. The reduction capability of tested strains for nitrate was not dramatic. All tested strains, however, showed the capability to produce nitrite reductase with the reduction amount of 58.46-75.80 mg/l of NO(2)(-). L. brevis and L. plantarum showed nitrate tolerance with the highest number of 8.71 log cfu/ml and 8.81 log cfu/ml, and L. brevis and L. sakei exhibited nitrite tolerance with the highest number of 8.24 log cfu/ml and 8.25 log cfu/ml, respectively. As a result, L. brevis, L. plantarum, and L. sakei isolated from kimchi showed a tolerance against nitrate or nitrite with a good nitrite reduction capability, indicating the satisfaction of one of the selection criteria to be used as starter culture for fermented sausages. Copyright © 2014 Elsevier Ltd. All rights reserved.

Isolation of Bacteria Capable of Growth with 2-Methylisoborneol and Geosmin as the Sole Carbon and Energy Sources

PubMed Central

Guttman, Lior

2012-01-01

Using a relatively simple enrichment technique, geosmin and 2-methylisoborneol (MIB)-biodegrading bacteria were isolated from a digestion basin in an aquaculture unit. Comparison of 16S rRNA gene sequences affiliated one of the three isolates with the Gram-positive genus Rhodococcus, while the other two isolates were found to be closely related to the Gram-negative family Comamonadaceae (Variovorax and Comamonas). Growth rates and geosmin and MIB removal rates by the isolates were determined under aerated and nonaerated conditions in mineral medium containing either of the two compounds as the sole carbon and energy source. All isolates exhibited their fastest growth under aerobic conditions, with generation times ranging from 3.1 to 5.7 h, compared to generation times of up to 19.1 h in the nonaerated flasks. Incubation of the isolates with additional carbon sources caused a significant increase in their growth rates, while removal rates of geosmin and MIB were significantly lower than those for incubation with only geosmin or MIB. By fluorescence in situ hybridization, members of the genera Rhodococcus and Comamonas were detected in geosmin- and MIB-enriched sludge from the digestion basin. PMID:22081577

Potential of Bacillus spp produces siderophores insuppressing thewilt disease of banana plants

NASA Astrophysics Data System (ADS)

Kesaulya, H.; Hasinu, J. V.; Tuhumury, G. NC

2018-01-01

In nature, different types of siderophore such as hydroxymate, catecholets and carboxylate, are produced by different bacteria. Bacillus spp were isolated from potato rhizospheric soil can produce siderophore of both catecholets and salicylate type with different concentrations. Various strains of Bacillus spp were tested for pathogen inhibition capability in a dual culture manner. The test results showed the ability of inhibition of pathogen isolated from banana wilt disease. From the result tested were found Bacillus niabensis Strain PT-32-1, Bacillus subtilis Strain SWI16b, Bacillus subtilis Strain HPC21, Bacillus mojavensis Strain JCEN3, and Bacillus subtilis Strain HPC24 showed different capabilities in suppressing pathogen.

Biodegradation of polyether algal toxins--isolation of potential marine bacteria.

PubMed

Shetty, Kateel G; Huntzicker, Jacqueline V; Rein, Kathleen S; Jayachandran, Krish

2010-12-01

Marine algal toxins such as brevetoxins, okadaic acid, yessotoxin, and ciguatoxin are polyether compounds. The fate of polyether toxins in the aqueous phase, particularly bacterial biotransformation of the toxins, is poorly understood. An inexpensive and easily available polyether structural analog salinomycin was used for enrichment and isolation of potential polyether toxin degrading aquatic marine bacteria from Florida bay area, and from red tide endemic sites in the South Florida Gulf coast. Bacterial growth on salinomycin was observed in most of the enrichment cultures from both regions with colony forming units ranging from 0 to 6×10(7) per mL. The salinomycin biodegradation efficiency of bacterial isolates determined using LC-MS ranged from 22% to 94%. Selected bacterial isolates were grown in media with brevetoxin as the sole carbon source to screen for brevetoxin biodegradation capability using ELISA. Out of the two efficient salinomycin biodegrading isolates MB-2 and MB-4, maximum brevetoxin biodegradation efficiency of 45% was observed with MB-4, while MB-2 was unable to biodegrade brevetoxin. Based on 16S rRNA sequence similarity MB-4 was found have a match with Chromohalobacter sp.

Antibiotic resistance is widespread in urban aquatic environments of Rio de Janeiro, Brazil.

PubMed

Coutinho, Felipe H; Silveira, Cynthia B; Pinto, Leonardo H; Salloto, Gigliola R B; Cardoso, Alexander M; Martins, Orlando B; Vieira, Ricardo P; Clementino, Maysa M

2014-10-01

Bacterial resistance to antibiotics has become a public health issue. Over the years, pathogenic organisms with resistance traits have been studied due to the threat they pose to human well-being. However, several studies raised awareness to the often disregarded importance of environmental bacteria as sources of resistance mechanisms. In this work, we analyze the diversity of antibiotic-resistant bacteria occurring in aquatic environments of the state of Rio de Janeiro, Brazil, that are subjected to distinct degrees of anthropogenic impacts. We access the diversity of aquatic bacteria capable of growing in increasing ampicillin concentrations through 16S rRNA gene libraries. This analysis is complemented by the characterization of antibiotic resistance profiles of isolates obtained from urban aquatic environments. We detect communities capable of tolerating antibiotic concentrations up to 600 times higher than the clinical levels. Among the resistant organisms are included potentially pathogenic species, some of them classified as multiresistant. Our results extend the knowledge of the diversity of antibiotic resistance among environmental microorganisms and provide evidence that the diversity of drug-resistant bacteria in aquatic habitats can be influenced by pollution.

Isolation of Thermophilic Lignin Degrading Bacteria from Oil-Palm Empty Fruit Bunch (EFB) Compost

NASA Astrophysics Data System (ADS)

Lai, C. M. T.; Chua, H. B.; Danquah, M. K.; Saptoro, A.

2017-06-01

Empty Fruit Bunch (EFB) is a potential and sustainable feedstock for bioethanol production due to its high cellulosic content and availability in Malaysia. Due to high lignin content of EFB and the lack of effective delignification process, commercial bioethanol production from EFB is presently not viable. Enzymatic delignification has been identified as one of the key steps in utilising EFB as a feedstock for bioethanol conversion. To date, limited work has been reported on the isolation of lignin degrading bacteria. Hence, there is a growing interest to search for new lignin degrading bacteria with greater tolerance to temperature and high level of ligninolytic enzymes for more effective lignin degradation. This study aimed to isolate and screen thermophilic ligninolytic microorganisms from EFB compost. Ten isolates were successfully isolated from EFB compost. Although they are not capable of decolorizing Methylene Blue (MB) dye under agar plate assay method, they are able to utilize lignin mimicked compound - guaiacol as a sole carbon on the agar plate assay. This infers that there is no correlation of ligninolytic enzymes with dye decolourization for all the isolates that have been isolated. However, they are able to produce ligninolytic enzymes (Lignin peroxidase, Manganese peroxidase, Laccase) in Minimal Salt Medium with Kraft Lignin (MSM-KL) with Lignin Peroxidase (LiP) as the predominant enzyme followed by Manganese Peroxidase (MnP) and Laccase (Lac). Among all the tested isolates, CLMT 29 has the highest LiP production up to 8.7673 U/mL following 24 h of growth.

Endophytic Bacteria Improve Plant Growth, Symbiotic Performance of Chickpea (Cicer arietinum L.) and Induce Suppression of Root Rot Caused by Fusarium solani under Salt Stress.

PubMed

Egamberdieva, Dilfuza; Wirth, Stephan J; Shurigin, Vyacheslav V; Hashem, Abeer; Abd Allah, Elsayed F

2017-01-01

Salinity causes disturbance in symbiotic performance of plants, and increases susceptibility of plants to soil-borne pathogens. Endophytic bacteria are an essential determinant of cross-tolerance to biotic and abiotic stresses in plants. The aim of this study was to isolate non-rhizobial endophytic bacteria from the root nodules of chickpea ( Cicer arietinum L.), and to assess their ability to improve plant growth and symbiotic performance, and to control root rot in chickpea under saline soil conditions. A total of 40 bacterial isolates from internal root tissues of chickpea grown in salinated soil were isolated. Four bacterial isolates, namely Bacillus cereus NUU1 , Achromobacter xylosoxidans NUU2, Bacillus thuringiensis NUU3, and Bacillus subtilis NUU4 colonizing root tissue demonstrated plant beneficial traits and/or antagonistic activity against F. solani and thus were characterized in more detail. The strain B. subtilis NUU4 proved significant plant growth promotion capabilities, improved symbiotic performance of host plant with rhizobia, and promoted yield under saline soil as compared to untreated control plants under field conditions. A combined inoculation of chickpea with M. ciceri IC53 and B. subtilis NUU4 decreased H 2 O 2 concentrations and increased proline contents compared to the un-inoculated plants indicating an alleviation of adverse effects of salt stress. Furthermore, the bacterial isolate was capable to reduce the infection rate of root rot in chickpea caused by F. solani . This is the first report of F. solani causing root rot of chickpea in a salinated soil of Uzbekistan. Our findings demonstrated that the endophytic B. subtilis strain NUU4 provides high potentials as a stimulator for plant growth and as biological control agent of chickpea root rot under saline soil conditions. These multiple relationships could provide promising practical approaches to increase the productivity of legumes under salt stress.

Endophytic Bacteria Improve Plant Growth, Symbiotic Performance of Chickpea (Cicer arietinum L.) and Induce Suppression of Root Rot Caused by Fusarium solani under Salt Stress

PubMed Central

Egamberdieva, Dilfuza; Wirth, Stephan J.; Shurigin, Vyacheslav V.; Hashem, Abeer; Abd_Allah, Elsayed F.

2017-01-01

Salinity causes disturbance in symbiotic performance of plants, and increases susceptibility of plants to soil-borne pathogens. Endophytic bacteria are an essential determinant of cross-tolerance to biotic and abiotic stresses in plants. The aim of this study was to isolate non–rhizobial endophytic bacteria from the root nodules of chickpea (Cicer arietinum L.), and to assess their ability to improve plant growth and symbiotic performance, and to control root rot in chickpea under saline soil conditions. A total of 40 bacterial isolates from internal root tissues of chickpea grown in salinated soil were isolated. Four bacterial isolates, namely Bacillus cereus NUU1, Achromobacter xylosoxidans NUU2, Bacillus thuringiensis NUU3, and Bacillus subtilis NUU4 colonizing root tissue demonstrated plant beneficial traits and/or antagonistic activity against F. solani and thus were characterized in more detail. The strain B. subtilis NUU4 proved significant plant growth promotion capabilities, improved symbiotic performance of host plant with rhizobia, and promoted yield under saline soil as compared to untreated control plants under field conditions. A combined inoculation of chickpea with M. ciceri IC53 and B. subtilis NUU4 decreased H2O2 concentrations and increased proline contents compared to the un-inoculated plants indicating an alleviation of adverse effects of salt stress. Furthermore, the bacterial isolate was capable to reduce the infection rate of root rot in chickpea caused by F. solani. This is the first report of F. solani causing root rot of chickpea in a salinated soil of Uzbekistan. Our findings demonstrated that the endophytic B. subtilis strain NUU4 provides high potentials as a stimulator for plant growth and as biological control agent of chickpea root rot under saline soil conditions. These multiple relationships could provide promising practical approaches to increase the productivity of legumes under salt stress. PMID:29033922

Isolation of efficient phosphate solubilizing bacteria capable of enhancing tomato plant growth

USDA-ARS?s Scientific Manuscript database

Phosphorus is one of the three macronutrients that are essential for plant growth and development. Inorganic phosphorus (P), which can make up to 70% of the total P content in soils, can exist in calcium-, aluminum-, or iron-complexed forms that are unavailable for plant use. As a result, mineral ph...

Glutathione S-transferase-encoding gene as a potential probe for environmental bacterial isolates capable of degrading polycyclic aromatic hydrocarbons.

PubMed Central

Lloyd-Jones, G; Lau, P C

1997-01-01

Homologs of the glutathione S-transferase (GST)-encoding gene were identified in a collection of aromatic hydrocarbon-degrading Sphingomonas spp. isolated from New Zealand, Antarctica, and the United States by using PCR primers designed from the GST-encoding gene of Sphingomonas paucimobilis EPA505. Sequence analysis of PCR fragments generated from these isolates and of the GST gene amplified from DNA extracted from polycyclic aromatic hydrocarbon (PAH)-contaminated soil revealed a high degree of conservation, which may make the GST-encoding gene a potentially useful marker for PAH-degrading bacteria. PMID:9251217

Bacterial Associations with Diatoms Influence Host Health in a Xenic Model System

NASA Astrophysics Data System (ADS)

Baker, L.; Kemp, P. F.

2016-02-01

Diatoms are photosynthetic unicellular eukaryotes found ubiquitously in aquatic systems. Microorganisms such as bacteria are frequently found attached to diatoms and may influence the fitness of their host. The most commonly used model organisms in studies of diatom-bacterial associations are Alteromonas and Marinobacter. Some strains of Alteromonas are capable of parasitism, producing chitinases or having algicidal interactions; some strains of Marinobacter are capable of mutualism, providing its host with vital nutrients. In this study, multiple strains of Alteromonas and Marinobacter were isolated from the centric diatom Chaetoceros sp KBDT20. Isolates were added back in varying concentration to cultures of their original xenic diatom host, and to cultures of a smaller, xenic naïve host, Chaetoceros sp. KBDT32. The growth rate of the diatom host was monitored using flow cytometry to assess the impact of the added bacterial isolates on host health. Our results suggest that all strains of Alteromonas tested have an antagonistic relationship with both the original as well as the naïve host while all strains of Marinobacter tested have a synergistic relationship with both diatom cultures. The functional basis for these relationships is being explored by supplementing xenic diatom cultures with materials essential for diatom growth that may be contributed by bacteria, such as B-vitamins and bioavailable trace metals. The colonization rates and competitive interactions between bacteria are investigated through surface colonization studies. The goal of this study is to better inform our understanding of how bacterial associates of diatom populations may contribute to their health, success, or failure in aquatic systems.

Metal Accumulation and Vanadium-Induced Multidrug Resistance by Environmental Isolates of Escherichia hermannii and Enterobacter cloacae

PubMed Central

Hernández, Alicia; Mellado, Rafael P.; Martínez, José L.

1998-01-01

Contaminated soils from an oil refinery were screened for the presence of microorganisms capable of accumulating either nickel, vanadium, or both metals. Three strains of bacteria that belonged to the family Enterobacteriaceae were selected. Two of them were Escherichia hermannii strains, and outer membrane profile (OMP) analysis showed that they were similar to a strain of clinical origin; the other one was an Enterobacter cloacae strain that differed from clinical isolates. The selected bacteria accumulated both nickel and vanadium. Growth in the presence of vanadium induced multidrug resistance phenotypes in E. hermannii and E. cloacae. Incubation with this metal changed the OMP profile of E. hermannii but did not produce variations in the expression of the major OMPs of E. cloacae. PMID:9797283

Isolation and Characterization of Bacteria Capable of Tolerating the Extreme Conditions of Clean Room Environments▿

PubMed Central

La Duc, Myron T.; Dekas, Anne; Osman, Shariff; Moissl, Christine; Newcombe, David; Venkateswaran, Kasthuri

2007-01-01

In assessing the bacterial populations present in spacecraft assembly, spacecraft test, and launch preparation facilities, extremophilic bacteria (requiring severe conditions for growth) and extremotolerant bacteria (tolerant to extreme conditions) were isolated. Several cultivation approaches were employed to select for and identify bacteria that not only survive the nutrient-limiting conditions of clean room environments but can also withstand even more inhospitable environmental stresses. Due to their proximity to spacefaring objects, these bacteria pose a considerable risk for forward contamination of extraterrestrial sites. Samples collected from four geographically distinct National Aeronautics and Space Administration clean rooms were challenged with UV-C irradiation, 5% hydrogen peroxide, heat shock, pH extremes (pH 3.0 and 11.0), temperature extremes (4°C to 65°C), and hypersalinity (25% NaCl) prior to and/or during cultivation as a means of selecting for extremotolerant bacteria. Culture-independent approaches were employed to measure viable microbial (ATP-based) and total bacterial (quantitative PCR-based) burdens. Intracellular ATP concentrations suggested a viable microbial presence ranging from below detection limits to 106 cells/m2. However, only 0.1 to 55% of these viable cells were able to grow on defined culture medium. Isolated members of the Bacillaceae family were more physiologically diverse than those reported in previous studies, including thermophiles (Geobacillus), obligate anaerobes (Paenibacillus), and halotolerant, alkalophilic species (Oceanobacillus and Exiguobacterium). Non-spore-forming microbes (α- and β-proteobacteria and actinobacteria) exhibiting tolerance to the selected stresses were also encountered. The multiassay cultivation approach employed herein enhances the current understanding of the physiological diversity of bacteria housed in these clean rooms and leads us to ponder the origin and means of translocation of thermophiles, anaerobes, and halotolerant alkalophiles into these environments. PMID:17308177

Isolation and characterization of bacteria capable of tolerating the extreme conditions of clean room environments.

PubMed

La Duc, Myron T; Dekas, Anne; Osman, Shariff; Moissl, Christine; Newcombe, David; Venkateswaran, Kasthuri

2007-04-01

In assessing the bacterial populations present in spacecraft assembly, spacecraft test, and launch preparation facilities, extremophilic bacteria (requiring severe conditions for growth) and extremotolerant bacteria (tolerant to extreme conditions) were isolated. Several cultivation approaches were employed to select for and identify bacteria that not only survive the nutrient-limiting conditions of clean room environments but can also withstand even more inhospitable environmental stresses. Due to their proximity to spacefaring objects, these bacteria pose a considerable risk for forward contamination of extraterrestrial sites. Samples collected from four geographically distinct National Aeronautics and Space Administration clean rooms were challenged with UV-C irradiation, 5% hydrogen peroxide, heat shock, pH extremes (pH 3.0 and 11.0), temperature extremes (4 degrees C to 65 degrees C), and hypersalinity (25% NaCl) prior to and/or during cultivation as a means of selecting for extremotolerant bacteria. Culture-independent approaches were employed to measure viable microbial (ATP-based) and total bacterial (quantitative PCR-based) burdens. Intracellular ATP concentrations suggested a viable microbial presence ranging from below detection limits to 10(6) cells/m(2). However, only 0.1 to 55% of these viable cells were able to grow on defined culture medium. Isolated members of the Bacillaceae family were more physiologically diverse than those reported in previous studies, including thermophiles (Geobacillus), obligate anaerobes (Paenibacillus), and halotolerant, alkalophilic species (Oceanobacillus and Exiguobacterium). Non-spore-forming microbes (alpha- and beta-proteobacteria and actinobacteria) exhibiting tolerance to the selected stresses were also encountered. The multiassay cultivation approach employed herein enhances the current understanding of the physiological diversity of bacteria housed in these clean rooms and leads us to ponder the origin and means of translocation of thermophiles, anaerobes, and halotolerant alkalophiles into these environments.

Numerical taxonomy of heavy metal tolerant bacteria isolated from the estuarine environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, D.A.; Austin, B.; Mills, A.L.

1977-01-01

Metal tolerant bacteria, totalling 301 strains, were isolated from water and sediment samples collected from Chesapeake Bay. Growth in the presence of 100 ppm cadmium, chromium, cobalt, lead, mercury and molybdenum was tested. In addition, the strains were examined for 118 biochemical, cultural, morphological, nutritional and physiological, characters and the data were analyzed by computer, using the simple matching and Jaccard coefficients. From sorted similarity matrices, 293 strains, 97% of the total, were removed in 12 clusters defined at the 80 to 85% similarity level. The clusters included Bacillus and Pseudomonas spp. and genera and species of Enterobacteriaceae. Three clusters,more » containing gram negative rods, were not identified. Several of the clusters were composed of strains exhibiting tolerance to a wide range of heavy metals, whereas three of the clusters contained bacteria that were capable of growth in the presence of only a few of the metals examined in this study. Antibiotic resistance of the metal resistant strains has also been examined.« less

Sustainable biodegradation of phenol by immobilized Bacillus sp. SAS19 with porous carbonaceous gels as carriers.

PubMed

Ke, Qian; Zhang, Yunge; Wu, Xilin; Su, Xiaomei; Wang, Yuyang; Lin, Hongjun; Mei, Rongwu; Zhang, Yu; Hashmi, Muhammad Zaffar; Chen, Chongjun; Chen, Jianrong

2018-09-15

In this study, high-efficient phenol-degrading bacterium Bacillus sp. SAS19 which was isolated from activated sludge by resuscitation-promoting factor (Rpf) addition, were immobilized on porous carbonaceous gels (CGs) for phenol degradation. The phenol-degrading capabilities of free and immobilized Bacillus sp. SAS19 were evaluated under various initial phenol concentrations. The obtained results showed that phenol could be removed effectively by both free and immobilized Bacillus sp. SAS19. Furthermore, for degradation of phenol at high concentrations, long-term utilization and recycling were more readily achieved for immobilized bacteria as compared to free bacteria. Immobilized bacteria exhibited significant increase in phenol-degrading capabilities in the third cycle of recycling and reuse, which demonstrated 87.2% and 100% of phenol (1600 mg/L) degradation efficiency at 12 and 24 h, respectively. The present study revealed that immobilized Bacillus sp. SAS19 can be potentially used for enhanced treatment of synthetic phenol-laden wastewater. Copyright © 2018 Elsevier Ltd. All rights reserved.

Application of Rhizobacteria for Plant Growth Promotion Effect and Biocontrol of Anthracnose Caused by Colletotrichum acutatum on Pepper

PubMed Central

Lamsal, Kabir; Kim, Sang Woo; Kim, Yun Seok

2012-01-01

In vitro and greenhouse screening of seven rhizobacterial isolates, AB05, AB10, AB11, AB12, AB14, AB15 and AB17, was conducted to investigate the plant growth promoting activities and inhibition against anthracnose caused by Colletotrichum acutatum in pepper. According to identification based on 16S rDNA sequencing, the majority of the isolates are members of Bacillus and a single isolate belongs to the genus Paenibacillus. All seven bacterial isolates were capable of inhibiting C. acutatum to various degrees. The results primarily showed that antibiotic substances produced by the selected bacteria were effective and resulted in strong antifungal activity against the fungi. However, isolate AB15 was the most effective bacterial strain, with the potential to suppress more than 50% mycelial growth of C. acutatum in vitro. Moreover, antibiotics from Paenibacillus polymyxa (AB15) and volatile compounds from Bacillus subtilis (AB14) exerted efficient antagonistic activity against the pathogens in a dual culture assay. In vivo suppression activity of selected bacteria was also analyzed in a greenhouse with the reference to their prominent in vitro antagonism efficacy. Induced systemic resistance in pepper against C. acutatum was also observed under greenhouse conditions. Where, isolate AB15 was found to be the most effective bacterial strain at suppressing pepper anthracnose under greenhouse conditions. Moreover, four isolates, AB10, AB12, AB15, and AB17, were identified as the most effective growth promoting bacteria under greenhouse conditions, with AB17 inducing the greatest enhancement of pepper growth. PMID:23323049

Biochemical and molecular characterization of potential phosphate-solubilizing bacteria in acid sulfate soils and their beneficial effects on rice growth.

PubMed

Panhwar, Qurban Ali; Naher, Umme Aminun; Shamshuddin, Jusop; Jusop, Shamshuddin; Othman, Radziah; Latif, Md Abdul; Ismail, Mohd Razi

2014-01-01

A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia). The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmol(c) kg(-1), respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB) including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis). The isolated strains were capable of producing indoleacetic acid (IAA) and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65%) existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM) was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils.

Biochemical and Molecular Characterization of Potential Phosphate-Solubilizing Bacteria in Acid Sulfate Soils and Their Beneficial Effects on Rice Growth

PubMed Central

Panhwar, Qurban Ali; Naher, Umme Aminun; Jusop, Shamshuddin; Othman, Radziah; Latif, Md Abdul; Ismail, Mohd Razi

2014-01-01

A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia). The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmolc kg−1, respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB) including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis). The isolated strains were capable of producing indoleacetic acid (IAA) and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65%) existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM) was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils. PMID:25285745

Identification of selected microorganisms from activated sludge capable of benzothiazole and benzotriazole transformation.

PubMed

Kowalska, Katarzyna; Felis, Ewa

2015-01-01

Benzothiazole (BT) and benzotriazole (BTA) are present in the environment - especially in urban and industrial areas, usually as anthropogenic micropollutants. BT and BTA have been found in the municipal and industrial wastewater, rivers, soil, groundwater, sediments and sludge. The origins of those substances' presence in the environment are various industry branches (food, chemical, metallurgical, electrical), households and surface runoff from industrial areas. Increasingly strict regulations on water quality and the fact that the discussed compounds are poorly biodegradable, make them a serious problem in the environment. Considering this, it is important to look for environmentally friendly and socially acceptable ways to remove BT and BTA. The aim of this study was to identify microorganisms capable of BT and BTA transformation or/and degradation in aquatic environment. Selected microorganisms were isolated from activated sludge. The identification of microorganisms capable of BT and BTA removal was possible using molecular biology techniques (PCR, DNA sequencing). Among isolated microorganisms of activated sludge are bacteria potentially capable of BT and BTA biotransformation and/or removal. The most common bacteria capable of BT and BTA transformation were Rhodococcus sp., Enterobacter sp., Arthrobacter sp. They can grow in a medium with BT and BTA as the only carbon source. Microorganisms previously adapted to the presence of the studied substances at a concentration of 10 mg/l, showed a greater rate of growth of colonies on media than microorganisms unconditioned to the presence of such compounds. Results of the biodegradation test suggest that BT was degraded to a greater extent than BTA, 98-100% and 11-19%, respectively.

Identification of non-Listeria spp. bacterial isolates yielding a β-D-glucosidase-positive phenotype on Agar Listeria according to Ottaviani and Agosti (ALOA).

PubMed

Angelidis, Apostolos S; Kalamaki, Mary S; Georgiadou, Sofia S

2015-01-16

Agar Listeria according to Ottaviani and Agosti (ALOA) is the mandatory medium used for the detection and enumeration of Listeria monocytogenes in foods according to the official International Organization for Standardization (ISO) methods. On ALOA, Listeria spp. appear as bluish-green colonies due to the production of β-D-glucosidase, an enzyme that cleaves 5-bromo-4-chloro-3-indolyl-β-D-glucopyranoside, a chromogenic substrate included in the formulation of the medium. The present work reports on bacterial isolates (n=64) from ready-to-eat soft cheeses, which are able to grow on ALOA, forming bluish-green colonies and therefore phenotypically resemble Listeria spp. All isolates were also capable of growing on the selective media PALCAM and RAPID L'mono. The isolates were characterised with biochemical tests including those specified in the ISO standards for the confirmation of Listeria spp. and identified via partial sequencing of their 16S rRNA gene. According to sequencing results the isolates represented 12 different bacterial species or species-groups belonging to seven different genera: Bacillus spp. (B. circulans, B. clausii, B. licheniformis and B. oleronius), Cellulosimicrobium spp. (C. funkei), Enterococcus spp. (E. faecalis, E. faecium/durans), Kocuria spp. (K. kristinae), Marinilactibacillus spp. (M. psychrotolerans), Rothia spp. (R. terrae) and Staphylococcus spp. (S. sciuri and S. saprophyticus subsp. saprophyticus/xylosus). Cellulosimicrobium spp. have never been previously isolated from foods. These results significantly extend the list of bacteria previously known as capable of growing on ALOA as bluish-green colonies and suggest that there may be room for further improvement in the medium's inhibitory properties towards non-Listeria spp., Gram-positive bacteria present in foods. Copyright © 2014 Elsevier B.V. All rights reserved.

Isolation and identification of poly beta hydroxybutyric acid accumulating bacteria of Staphylococcal sp. and characterization of biodegradable polyester.

PubMed

Roy, Bappaditya; Banerjee, Rajat; Chatterjee, Sumana

2009-04-01

Staphylococcus sp. strain BP/SU1, capable of degrading the biopolymer and utilize it as a source of carbon and energy, was isolated from activated sludge using METABOLIX (MBX D411G). It was found that this strain was capable of accumulating poly(3-hydroxybutyric acid) P(3-HB), as granule poly (3-hydroxybutyric acid), p(3-HB), inclusion bodies when grown under suitable nutrient conditions. These strains could sustain cell growth up to a dry mass of 9.24 g/l with a doubling time of 8 to 10 hr and could accumulate P(3-HB) as granular inclusion bodies to a cell dry weight of more than 12%. P(3-HB) accumulated by this organism was isolated and characterized through NMR, FT-IR spectroscopy, UV Spectroscopy, Mass spectroscopy and Differential Scanning Calorimetry. P(3-HB) granules so isolated showed physical and chemical properties that should be possessed by a superior quality thermoplastic biopolymer.

Isolation of a rice endophytic bacterium, Pantoea sp. Sd-1, with ligninolytic activity and characterization of its rice straw degradation ability.

PubMed

Xiong, X Q; Liao, H D; Ma, J S; Liu, X M; Zhang, L Y; Shi, X W; Yang, X L; Lu, X N; Zhu, Y H

2014-02-01

This study focused on an endophytic bacterial strain, Pantoea sp. Sd-1, which can be used to degrade lignin and rice straw. This strain was isolated from rice seeds by an optimized surface sterilization method. Pantoea sp. Sd-1 showed exceptional ability to degrade rice straw and lignin. In rice straw or kraft lignin-containing medium supplemented with 1% glucose and 0.5% peptone, Pantoea sp. Sd-1 effectively reduced the rice straw mass weight by 54.5% after 6 days of treatment. The strain was also capable of reducing the lignin colour (52.4%) and content (69.1%) after 4 days of incubation. The findings suggested that the rice endophytic bacterium Pantoea sp. Sd-1 could be applied for the degradation of lignocellulose biomass, such as rice straw. Rice straw, an abundant agricultural by-product in China, is very difficult to degrade because of its high lignin content. Due to the immense environmental adaptability and biochemical versatility of bacteria, endophytic bacteria are useful resources for biodegradation. In this study, we screened for endophytic bacteria capable of biodegrading rice straw and lignin and obtained one strain, Pantoea sp. Sd-1, with suitable characteristics. Sd-1 could be used for degradation of rice straw and lignin, and may play an important role in biodegradation of this agricultural by-product. © 2013 The Society for Applied Microbiology.

Isolation of isoprene degrading bacteria from soils, development of isoA gene probes and identification of the active isoprene-degrading soil community using DNA-stable isotope probing.

PubMed

El Khawand, Myriam; Crombie, Andrew T; Johnston, Antonia; Vavlline, Dmitrii V; McAuliffe, Joseph C; Latone, Jacob A; Primak, Yuliya A; Lee, Sang-Kyu; Whited, Gregg M; McGenity, Terry J; Murrell, J Colin

2016-09-01

Emissions of biogenic volatile organic compounds (bVOCs), are an important element in the global carbon cycle, accounting for a significant proportion of fixed carbon. They contribute directly and indirectly to global warming and climate change and have a major effect on atmospheric chemistry. Plants emit isoprene to the atmosphere in similar quantities to emissions of methane from all sources and each accounts for approximately one third of total VOCs. Although methanotrophs, capable of growth on methane, have been intensively studied, we know little of isoprene biodegradation. Here, we report the isolation of two isoprene-degrading strains from the terrestrial environment and describe the design and testing of polymerase chain reaction (PCR) primers targeting isoA, the gene encoding the active-site component of the conserved isoprene monooxygenase, which are capable of retrieving isoA sequences from isoprene-enriched environmental samples. Stable isotope probing experiments, using biosynthesized (13) C-labelled isoprene, identified the active isoprene-degrading bacteria in soil. This study identifies novel isoprene-degrading strains using both culture-dependent and, for the first time, culture-independent methods and provides the tools and foundations for continued investigation of the biogeography and molecular ecology of isoprene-degrading bacteria. © 2016 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

Brazilian artisanal ripened cheeses as sources of proteolytic lactic acid bacteria capable of reducing cow milk allergy.

PubMed

Biscola, V; Choiset, Y; Rabesona, H; Chobert, J-M; Haertlé, T; Franco, B D G M

2018-04-13

The objective was to obtain lactic acid bacteria (LAB) capable of hydrolysing immunoreactive proteins in milk, to optimize the hydrolysis, to determine the proteolysis kinetics and to test the safety of the best hydrolytic strain. Brazilian cheese was used as source of LAB capable of hydrolysing main milk allergens. Proteolytic isolates were submitted to RAPD-PCR for the characterization of clonal diversity. Optimized hydrolysis was strain and protein fraction dependent. 16S rDNA sequencing identified three proteolytic strains: Enterococcus faecalis VB43, that hydrolysed α S1 -, α S2 - and β-caseins, α-lactalbumin and β-lactoglobulin (partial hydrolysis), and Pediococcus acidilactici VB90 and Weissella viridescens VB111, that caused partial hydrolysis of α S1 - and α S2 -caseins. Enterococcus faecalis VB43 tested negative for virulence genes asa1, agg, efaA, hyl, esp, cylL L and cylL S but positive for genes ace and gelE. Ethylenediamine tetra-acetic acid inhibited the proteolysis, indicating that the main proteases of E. faecalis VB43 are metalloproteases. Brazilian artisanal cheese is a good source of LAB capable of hydrolysing allergenic proteins in milk. One isolate (E. faecalis VB43) presented outstanding activity against these proteins and lacked most of the tested virulence genes. Enterococcus faecalis VB43 presents good potential for the manufacture of hypoallergenic dairy products. © 2018 The Society for Applied Microbiology.

The Role of 2,4-diacetylphloroglucinol- and phenazine-1-carboxylic acid-producing Pseudomonas spp. in Natural Protection of Wheat from Soilborne Pathogens

USDA-ARS?s Scientific Manuscript database

Fluorescent Pseudomonas isolated from the rhizosphere of diverse plants have been studied as biocontrol agents of soilborne pathogens worldwide. Certain strains of these bacteria are capable of exerting a variety of mechanisms of plant growth promotion and protection, including the production of the...

Isolation and molecular identification of landfill bacteria capable of growing on di-(2-ethylhexyl) phthalate and deteriorating PVC materials

PubMed Central

Latorre, Isomar; Hwang, Sangchul; Montalvo-Rodriguez, Rafael

2012-01-01

Waste materials containing Di-(2-ethylhexyl) phthalate (DEHP), a suspected endocrine disruptor and reasonably anticipated human carcinogen, are typically disposed of in landfills. Despite this, very few studies had been conducted to isolate and identify DEHP-degrading bacteria in landfill leachate. Therefore, this study was conducted to isolate and characterize bacteria in landfill leachate growing on DEHP as the sole carbon source and deteriorating PVC materials. Four strains LHM1, LHM2, LHM3 and LHM4, not previously reported as DEHP-degraders, were identified via 16S rRNA gene sequence. Gram-positive strains LHM1 and LHM2 had a greater than 97% similarity with Chryseomicrobium imtechense MW 10(T) and Lysinibacillus fusiformis NBRC 15717(T), respectively. Gram-negative strains LHM3 and LHM4 were related to Acinetobacter calcoaceticus DSM 30006(T) (90.7% similarity) and Stenotrophomonas pavanii ICB 89(T) (96.0% similarity), respectively. Phylogenetic analysis also corroborated these similarities of strains LHM1 and LHM2 to the corresponding bacteria species. Strains LHM2 and LHM4 grew faster than strains LHM1 and LHM3 in the enrichment where DEHP was the sole carbon source. When augmented to the reactors with PVC shower curtains containing DEHP, strains LHM1 and LHM2 developed greater optical densities in the solution phase and thicker biofilm on the surfaces of the shower curtains. PMID:22934997

Bacillus species (BT42) isolated from Coffea arabica L. rhizosphere antagonizes Colletotrichum gloeosporioides and Fusarium oxysporum and also exhibits multiple plant growth promoting activity.

PubMed

Kejela, Tekalign; Thakkar, Vasudev R; Thakor, Parth

2016-11-18

Colletotrichum and Fusarium species are among pathogenic fungi widely affecting Coffea arabica L., resulting in major yield loss. In the present study, we aimed to isolate bacteria from root rhizosphere of the same plant that is capable of antagonizing Colletotrichum gloeosporioides and Fusarium oxysporum as well as promotes plant growth. A total of 42 Bacillus species were isolated, one of the isolates named BT42 showed maximum radial mycelial growth inhibition against Colletotrichum gloeosporioides (78%) and Fusarium oxysporum (86%). BT42 increased germination of Coffee arabica L. seeds by 38.89%, decreased disease incidence due to infection of Colletotrichum gloeosporioides to 2.77% and due to infection of Fusarium oxysporum to 0 (p < 0.001). The isolate BT42 showed multiple growth-promoting traits. The isolate showed maximum similarity with Bacillus amyloliquefaciens. Bacillus species (BT42), isolated in the present work was found to be capable of antagonizing the pathogenic effects of Colletotrichum gloeosporioides and Fusarium oxysporum. The mechanism of action of inhibition of the pathogenic fungi found to be synergistic effects of secondary metabolites, lytic enzymes, and siderophores. The major inhibitory secondary metabolite identified as harmine (β-carboline alkaloids).

Phytochemical Screening and Antimicrobial Activity of Some Medicinal Plants Against Multi-drug Resistant Bacteria from Clinical Isolates

PubMed Central

Dahiya, Praveen; Purkayastha, Sharmishtha

2012-01-01

The in vitro antibacterial activity of various solvents and water extracts of aloe vera, neem, bryophyllum, lemongrass, tulsi, oregano, rosemary and thyme was assessed on 10 multi-drug resistant clinical isolates from both Gram-positive and Gram-negative bacteria and two standard strains including Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922. The zone of inhibition as determined by agar well diffusion method varied with the plant extract, the solvent used for extraction, and the organism tested. Klebsiella pneumoniae 2, Escherichia coli 3 and Staphylococcus aureus 3 were resistant to the plant extracts tested. Moreover, water extracts did not restrain the growth of any tested bacteria. Ethanol and methanol extracts were found to be more potent being capable of exerting significant inhibitory activities against majority of the bacteria investigated. Staphylococcus aureus 1 was the most inhibited bacterial isolate with 24 extracts (60%) inhibiting its growth whereas Escherichia coli 2 exhibited strong resistance being inhibited by only 11 extracts (28%). The results obtained in the agar diffusion plates were in fair correlation with that obtained in the minimum inhibitory concentration tests. The minimum inhibitory concentration of tulsi, oregano, rosemary and aloe vera extracts was found in the range of 1.56-6.25 mg/ml for the multi-drug resistant Staphylococcus aureus isolates tested whereas higher values (6.25-25 mg/ml) were obtained against the multi-drug resistant isolates Klebsiella pneumoniae 1 and Escherichia coli 1 and 2. Qualitative phytochemical analysis demonstrated the presence of tannins and saponins in all plants tested. Thin layer chromatography and bioautography agar overlay assay of ethanol extracts of neem, tulsi and aloe vera indicated flavonoids and tannins as major active compounds against methicillin-resistant Staphylococcus aureus. PMID:23716873

Assessing the hydrocarbon degrading potential of indigenous bacteria isolated from crude oil tank bottom sludge and hydrocarbon-contaminated soil of Azzawiya oil refinery, Libya.

PubMed

Mansur, Abdulatif A; Adetutu, Eric M; Kadali, Krishna K; Morrison, Paul D; Nurulita, Yuana; Ball, Andrew S

2014-09-01

The disposal of hazardous crude oil tank bottom sludge (COTBS) represents a significant waste management burden for South Mediterranean countries. Currently, the application of biological systems (bioremediation) for the treatment of COTBS is not widely practiced in these countries. Therefore, this study aims to develop the potential for bioremediation in this region through assessment of the abilities of indigenous hydrocarbonoclastic microorganisms from Libyan Hamada COTBS for the biotreatment of Libyan COTBS-contaminated environments. Bacteria were isolated from COTBS, COTBS-contaminated soil, treated COTBS-contaminated soil, and uncontaminated soil using Bushnell Hass medium amended with Hamada crude oil (1 %) as the main carbon source. Overall, 49 bacterial phenotypes were detected, and their individual abilities to degrade Hamada crude and selected COBTS fractions (naphthalene, phenanthrene, eicosane, octadecane and hexane) were evaluated using MT2 Biolog plates. Analyses using average well colour development showed that ~90 % of bacterial isolates were capable of utilizing representative aromatic fractions compared to 51 % utilization of representative aliphatics. Interestingly, more hydrocarbonoclastic isolates were obtained from treated contaminated soils (42.9 %) than from COTBS (26.5 %) or COTBS-contaminated (30.6 %) and control (0 %) soils. Hierarchical cluster analysis (HCA) separated the isolates into two clusters with microorganisms in cluster 2 being 1.7- to 5-fold better at hydrocarbon degradation than those in cluster 1. Cluster 2 isolates belonged to the putative hydrocarbon-degrading genera; Pseudomonas, Bacillus, Arthrobacter and Brevundimonas with 57 % of these isolates being obtained from treated COTBS-contaminated soil. Overall, this study demonstrates that the potential for PAH degradation exists for the bioremediation of Hamada COTBS-contaminated environments in Libya. This represents the first report on the isolation of hydrocarbonoclastic bacteria from Libyan COTBS and COTBS-contaminated soil.

Exopolysaccharide-producing lactic acid bacteria strains from traditional Thai fermented foods: isolation, identification and exopolysaccharide characterization.

PubMed

Smitinont, T; Tansakul, C; Tanasupawat, S; Keeratipibul, S; Navarini, L; Bosco, M; Cescutti, P

1999-10-15

Lactic Acid Bacteria (LAB) isolated from various traditional Thai fermented foods were screened for exopolysaccharides (EPS) production. From 104 isolates, two rod-shaped and five coccal-shaped LAB were able to produce EPS from sucrose on solid media. However, only the cocci were capable of producing EPS in liquid media and these were identified as Pediococcus pentosaceus. Pediococcus pentosaceus strains AP-1 and AP-3 produced EPS in high yield. In liquid media containing sucrose as carbon source, the amount of EPS produced by AP-1 and AP-3 strains was 6.0 and 2.5 g/L, respectively. The isolated and purified EPSs were chemically characterized. On the basis of sugar composition, methylation analysis and nuclear magnetic resonance spectroscopy, both the EPSs were shown to belong to the same dextran class. In particular, both EPSs differed from linear dextran by branching through 3,6-di-Osubstituted alpha-D-glucopyranosyl residues. The EPS from P. pentosaceus AP-3 was characterized by a relatively higher degree of branching and by a higher molecular weight than that from P. pentosaceus AP-1.

Bacteria as growth-promoting agents for citrus rootstocks.

PubMed

Giassi, Valdionei; Kiritani, Camila; Kupper, Katia Cristina

2016-09-01

The microbial community plays an essential role in maintaining the ecological balance of soils. Interactions between microorganisms and plants have a major influence on the nutrition and health of the latter, and growth-promoting rhizobacteria can be used to improve plant development through a wide range of mechanisms. Therefore, the objective of the present study was to evaluate bacteria as growth-promoting agents for citrus rootstocks. A total of 30 bacterial isolates (11 of Bacillus spp., 11 actinobacteria, and 8 lactic acid bacteria) were evaluated in vitro for indoleacetic acid production, phosphate solubilization, and nitrogen (N) fixation. In vivo testing consisted of growth promotion trials of the bacterial isolates that yielded the best results on in vitro tests with three rootstocks: Swingle citrumelo [Citrus×paradisi Macfad cv. Duncan×Poncirus trifoliata (L.) Raf.], Sunki mandarin (Citrus sunki Hort. ex Tan), and rangpur (Citrus×limonia Osbeck). The parameters of interest were height, number of leaves, stem diameter, shoot and root dry mass, and total dry mass at 150days after germination. The results showed that most bacterial isolates were capable of IAA production. Only one lactic acid bacterium isolate (BL06) solubilized phosphate, with a high solubilization index (PSI>3). In the actinobacteria group, isolates ACT01 (PSI=2.09) and ACT07 (PSI=2.01) exhibited moderate phosphate-solubilizing properties. Of the Bacillus spp. isolates, only CPMO6 and BM17 solubilized phosphate. The bacterial isolates that most fixated nitrogen were BM17, ACT11, and BL24. In the present study, some bacteria were able to promote growth of citrus rootstocks; however, this response was dependent on plant genotype and isolate. Bacillus spp. BM16 and CPMO4 were able to promote growth of Swingle citrumelo. In Sunki mandarin plants, the best treatment results were obtained with BM17 (Bacillus sp.) and ACT11 (actinobacteria). For Rangpur lime rootstock, only BM05 (Bacillus sp.) was able to promote increase in two parameters assessed, height and number of leaves. When the bacterial isolates were used in mixture there was not promoted growth of plants on rootstocks. This fact may be associated with the different mechanisms of action of each bacteria involved or with the presence of competition among the microorganisms of the mixture. Copyright © 2016 Elsevier GmbH. All rights reserved.

Toward Understanding Phage:Host Interactions in the Rumen; Complete Genome Sequences of Lytic Phages Infecting Rumen Bacteria

PubMed Central

Gilbert, Rosalind A.; Kelly, William J.; Altermann, Eric; Leahy, Sinead C.; Minchin, Catherine; Ouwerkerk, Diane; Klieve, Athol V.

2017-01-01

The rumen is known to harbor dense populations of bacteriophages (phages) predicted to be capable of infecting a diverse range of rumen bacteria. While bacterial genome sequencing projects are revealing the presence of phages which can integrate their DNA into the genome of their host to form stable, lysogenic associations, little is known of the genetics of phages which utilize lytic replication. These phages infect and replicate within the host, culminating in host lysis, and the release of progeny phage particles. While lytic phages for rumen bacteria have been previously isolated, their genomes have remained largely uncharacterized. Here we report the first complete genome sequences of lytic phage isolates specifically infecting three genera of rumen bacteria: Bacteroides, Ruminococcus, and Streptococcus. All phages were classified within the viral order Caudovirales and include two phage morphotypes, representative of the Siphoviridae and Podoviridae families. The phage genomes displayed modular organization and conserved viral genes were identified which enabled further classification and determination of closest phage relatives. Co-examination of bacterial host genomes led to the identification of several genes responsible for modulating phage:host interactions, including CRISPR/Cas elements and restriction-modification phage defense systems. These findings provide new genetic information and insights into how lytic phages may interact with bacteria of the rumen microbiome. PMID:29259581

Dissolution of Arsenic Minerals Mediated by Dissimilatory Arsenate Reducing Bacteria: Estimation of the Physiological Potential for Arsenic Mobilization

PubMed Central

Lukasz, Drewniak; Liwia, Rajpert; Aleksandra, Mantur; Aleksandra, Sklodowska

2014-01-01

The aim of this study was characterization of the isolated dissimilatory arsenate reducing bacteria in the context of their potential for arsenic removal from primary arsenic minerals through reductive dissolution. Four strains, Shewanella sp. OM1, Pseudomonas sp. OM2, Aeromonas sp. OM4, and Serratia sp. OM17, capable of anaerobic growth with As (V) reduction, were isolated from microbial mats from an ancient gold mine. All of the isolated strains: (i) produced siderophores that promote dissolution of minerals, (ii) were resistant to dissolved arsenic compounds, (iii) were able to use the dissolved arsenates as the terminal electron acceptor, and (iii) were able to use copper minerals containing arsenic minerals (e.g., enargite) as a respiratory substrate. Based on the results obtained in this study, we postulate that arsenic can be released from some As-bearing polymetallic minerals (such as copper ore concentrates or middlings) under reductive conditions by dissimilatory arsenate reducers in indirect processes. PMID:24724102

[Isolation, identification and characterization of a diethylstilbestrol-degrading bacterial strain Serratia sp].

PubMed

Xu, Ran-Fang; Sun, Min-Xia; Liu, Juan; Wang, Hong; Li, Xin; Zhu, Xue-Zhu; Ling, Wan-Ting

2014-08-01

Utilizing the diethylstilbestrol (DES)-degrading bacteria to biodegrade DES is a most reliable technique for cleanup of DES pollutants from the environment. However, little information is available heretofore on the isolation of DES-degrading bacteria and their DES removal performance in the environment. A novel bacterium capable of degrading DES was isolated from the activated sludge of a wastewater treatment plant. According to its morphology, physiochemical characteristics, and 16S rDNA sequence analysis, this strain was identified as Serratia sp.. The strain was an aerobic bacterium, and it could degrade 68.3% of DES (50 mg x L(-1)) after culturing for 7 days at 30 degrees C, 150 r x min(-1) in shaking flasks. The optimal conditions for DES biodegradation by the obtained strain were 30 degrees C, 40-60 mg x L(-1) DES, pH 7.0, 5% of inoculation volume, 0 g x L(-1) of added NaCl, and 10 mL of liquid medium volume in 100 mL flask.

Dissolution of arsenic minerals mediated by dissimilatory arsenate reducing bacteria: estimation of the physiological potential for arsenic mobilization.

PubMed

Lukasz, Drewniak; Liwia, Rajpert; Aleksandra, Mantur; Aleksandra, Sklodowska

2014-01-01

The aim of this study was characterization of the isolated dissimilatory arsenate reducing bacteria in the context of their potential for arsenic removal from primary arsenic minerals through reductive dissolution. Four strains, Shewanella sp. OM1, Pseudomonas sp. OM2, Aeromonas sp. OM4, and Serratia sp. OM17, capable of anaerobic growth with As (V) reduction, were isolated from microbial mats from an ancient gold mine. All of the isolated strains: (i) produced siderophores that promote dissolution of minerals, (ii) were resistant to dissolved arsenic compounds, (iii) were able to use the dissolved arsenates as the terminal electron acceptor, and (iii) were able to use copper minerals containing arsenic minerals (e.g., enargite) as a respiratory substrate. Based on the results obtained in this study, we postulate that arsenic can be released from some As-bearing polymetallic minerals (such as copper ore concentrates or middlings) under reductive conditions by dissimilatory arsenate reducers in indirect processes.

Application of immobilized synthetic anti-lipopolysaccharide peptides for the isolation and detection of bacteria.

PubMed

Sandetskaya, N; Engelmann, B; Brandenburg, K; Kuhlmeier, D

2015-08-01

The molecular detection of microorganisms in liquid samples generally requires their enrichment or isolation. The aim of our study was to evaluate the capture and pre-concentration of bacteria by immobilized particular cationic antimicrobial peptides, called synthetic anti-lipopolysaccharide peptides (SALP). For the proof-of-concept and screening of different SALP, the peptides were covalently immobilized on glass slides, and the binding of bacteria was confirmed by microscopic examination of the slides or their scanning, in case of fluorescent bacterial cells. The most efficient SALP was further tethered to magnetic beads. SALP beads were used for the magnetic capture of Escherichia coli in liquid samples. The efficiency of this strategy was evaluated using polymerase chain reaction (PCR). Covalently immobilized SALP were capable of capturing bacteria in liquid samples. However, PCR was hampered by the unspecific binding of DNA to the positively charged peptide. We developed a method for DNA recovery by the enzymatic digestion of the peptide, which allowed for a successful PCR, though the method had its own adverse impact on the detection and, thus, did not allow for the reliable quantitative analysis of the pathogen enrichment. Immobilized SALP can be used as capture molecules for bacteria in liquid samples and can be recommended for the design of the assays or decontamination of the fluids. For the accurate subsequent detection of bacteria, DNA-independent methods should be used.

Biodegradation of polyether algal toxins–Isolation of potential marine bacteria

PubMed Central

SHETTY, KATEEL G.; HUNTZICKER, JACQUELINE V.; REIN, KATHLEEN S.; JAYACHANDRAN, KRISH

2012-01-01

Marine algal toxins such as brevetoxins, okadaic acid, yessotoxin, and ciguatoxin are polyether compounds. The fate of polyether toxins in the aqueous phase, particularly bacterial biotransformation of the toxins, is poorly understood. An inexpensive and easily available polyether structural analog salinomycin was used for enrichment and isolation of potential polyether toxin degrading aquatic marine bacteria from Florida bay area, and from red tide endemic sites in the South Florida Gulf coast. Bacterial growth on salinomycin was observed in most of the enrichment cultures from both regions with colony forming units ranging from 0 to 6 × 107 per mL. The salinomycin biodegradation efficiency of bacterial isolates determined using LC-MS ranged from 22% to 94%. Selected bacterial isolates were grown in media with brevetoxin as the sole carbon source to screen for brevetoxin biodegradation capability using ELISA. Out of the two efficient salinomycin biodegrading isolates MB-2 and MB-4, maximum brevetoxin biodegradation efficiency of 45% was observed with MB-4, while MB-2 was unable to biodegrade brevetoxin. Based on 16S rRNA sequence similarity MB-4 was found have a match with Chromohalobacter sp. PMID:20954040

Arsenic-resistant and plant growth-promoting Firmicutes and γ-Proteobacteria species from industrially polluted irrigation water and corresponding cropland.

PubMed

Qamar, N; Rehman, Y; Hasnain, S

2017-09-01

The aim of the study was to explore irrigation water polluted with industrial waste and corresponding cropland to screen bacteria for As detoxification and plant growth promotion. Plant growth-promoting (PGP) As-resistant cropland bacteria were isolated from contaminated irrigation water and corresponding agricultural soil. Phylogenetic analysis revealed that the isolates belonged to two distinct bacterial lineages; Firmicutes and γ-Proteobacteria. Maximum As(V) resistance was exhibited by Klebsiella pneumoniae T22 and Klebsiella oxytoca N53 (550 mmol l -1 ), whereas maximum resistance against As(III) was exhibited by K. oxytoca N53 (200 mmol l -1 ). Maximum As(V) reduction was shown by K. pneumoniae T22 (6·7 mmol l -1 ), whereas maximum As(III) oxidation was exhibited by Bacillus subtilis T23 (4·8 mmol l -1 ). As resistance genes arsB and ACR3 were detected in many of the isolates through polymerase chain reaction. Many of these isolates exhibited PGP traits such as hydrogen cyanide and auxin production as well as phosphate solubilization. The bacterial strains were able to enhance Triticum aestivum growth both in the absence and presence of As, and statistically significant increase in shoot and root lengths was observed especially in case of Acinetobacter lwoffii T24 and Citrobacter freundii N52-treated plants. Cropland bacteria have the ability to support plant growth. Bacteria of croplands irrigated with industrially polluted water develop resistance against toxicants. These bacteria are helpful for the plant growth in such contaminated lands. The bacteria capable of both As detoxification and plant growth promotion, such as A. lwoffii T24 and C. freundii N52, are ideal for remediation and reclamation of polluted lands for agriculture purposes. © 2017 The Society for Applied Microbiology.

Molecular identification and genotyping of Pseudomonas aeruginosa isolated from cystic fibrosis and non-cystic fibrosis patients with bronchiectasis.

PubMed

Eusebio, Nadia; Amorim, Adelina A; Gamboa, Fernanda; Araujo, Ricardo

2015-03-01

There is no standard methodology for the molecular identification and genotyping of Pseudomonas aeruginosa which are frequently isolated in bronchiectasis patients. Hence, the main goal of this work was to propose a methodology capable to simultaneously identify and genotype, in less than 6 h, clinical P. aeruginosa collected from cystic fibrosis (CF) and non-CF patients with bronchiectasis. Molecular analyses were conducted in clinical isolates by testing the newly colony-PCR strategy and SNaPaer assay. A total of 207 isolates of P. aeruginosa were collected from clinical samples. To assess the assay specificity, other Gram-negative non-aeruginosa bacteria, namely Pseudomonas and Burkholderia, were tested. The complete group of 23 markers included in the SNaPaer panel was observed exclusively in P. aeruginosa; more than 18 markers failed in other bacteria. A total of 43 SnaP profiles were obtained for clinical P. aeruginosa, being the profiles highly patient-specific. Six CF patients were colonized with P. aeruginosa isolates with very distinct SnaP profiles, particularly following adjustments on antibiotic therapy, thus suggesting changes on the dynamics and dominance of these bacteria. SnaPaer proved to be a good and reliable tool for identification and genotyping of clinical P. aeruginosa in a single-tube multiplex PCR. Combined with the proposed colony-PCR strategy, SnaPaer assay facilitates the molecular analysis of P. aeruginosa. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Functional Role of Bacteria from Invasive Phragmites australis in Promotion of Host Growth.

PubMed

Soares, M A; Li, H-Y; Kowalski, K P; Bergen, M; Torres, M S; White, J F

2016-08-01

We hypothesize that bacterial endophytes may enhance the competitiveness and invasiveness of Phragmites australis. To evaluate this hypothesis, endophytic bacteria were isolated from P. australis. The majority of the shoot meristem isolates represent species from phyla Firmicutes, Proteobacteria, and Actinobacteria. We chose one species from each phylum to characterize further and to conduct growth promotion experiments in Phragmites. Bacteria tested include Bacillus amyloliquefaciens A9a, Achromobacter spanius B1, and Microbacterium oxydans B2. Isolates were characterized for known growth promotional traits, including indole acetic acid (IAA) production, secretion of hydrolytic enzymes, phosphate solubilization, and antibiosis activity. Potentially defensive antimicrobial lipopeptides were assayed for through application of co-culturing experiments and mass spectrometer analysis. B. amyloliquefaciens A9a and M. oxydans B2 produced IAA. B. amyloliquefaciens A9a secreted antifungal lipopeptides. Capability to promote growth of P. australis under low nitrogen conditions was evaluated in greenhouse experiments. All three isolates were found to increase the growth of P. australis under low soil nitrogen conditions and showed increased absorption of isotopic nitrogen into plants. This suggests that the Phragmites microbes we evaluated most likely promote growth of Phragmites by enhanced scavenging of nitrogenous compounds from the rhizosphere and transfer to host roots. Collectively, our results support the hypothesis that endophytic bacteria play a role in enhancing growth of P. australis in natural populations. Gaining a better understanding of the precise contributions and mechanisms of endophytes in enabling P. australis to develop high densities rapidly could lead to new symbiosis-based strategies for management and control of the host.

Functional role of bacteria from invasive Phragmites australis in promotion of host growth

USGS Publications Warehouse

Soares, M. A.; Li, H-Y; Kowalski, Kurt P.; Bergen, M.; Torres, M. S.; White, J. F.

2016-01-01

We hypothesize that bacterial endophytes may enhance the competitiveness and invasiveness of Phragmites australis. To evaluate this hypothesis, endophytic bacteria were isolated from P. australis. The majority of the shoot meristem isolates represent species from phyla Firmicutes, Proteobacteria, and Actinobacteria. We chose one species from each phylum to characterize further and to conduct growth promotion experiments in Phragmites. Bacteria tested include Bacillus amyloliquefaciens A9a, Achromobacter spanius B1, and Microbacterium oxydans B2. Isolates were characterized for known growth promotional traits, including indole acetic acid (IAA) production, secretion of hydrolytic enzymes, phosphate solubilization, and antibiosis activity. Potentially defensive antimicrobial lipopeptides were assayed for through application of co-culturing experiments and mass spectrometer analysis. B. amyloliquefaciens A9a and M. oxydans B2 produced IAA. B. amyloliquefaciens A9a secreted antifungal lipopeptides. Capability to promote growth of P. australis under low nitrogen conditions was evaluated in greenhouse experiments. All three isolates were found to increase the growth of P. australis under low soil nitrogen conditions and showed increased absorption of isotopic nitrogen into plants. This suggests that the Phragmites microbes we evaluated most likely promote growth of Phragmites by enhanced scavenging of nitrogenous compounds from the rhizosphere and transfer to host roots. Collectively, our results support the hypothesis that endophytic bacteria play a role in enhancing growth of P. australis in natural populations. Gaining a better understanding of the precise contributions and mechanisms of endophytes in enabling P. australis to develop high densities rapidly could lead to new symbiosis-based strategies for management and control of the host.

Genomics of Methylotrophy in Gram-Positive Methylamine-Utilizing Bacteria

PubMed Central

McTaggart, Tami L.; Beck, David A. C.; Setboonsarng, Usanisa; Shapiro, Nicole; Woyke, Tanja; Lidstrom, Mary E.; Kalyuzhnaya, Marina G.; Chistoserdova, Ludmila

2015-01-01

Gram-positive methylotrophic bacteria have been known for a long period of time, some serving as model organisms for characterizing the specific details of methylotrophy pathways/enzymes within this group. However, genome-based knowledge of methylotrophy within this group has been so far limited to a single species, Bacillus methanolicus (Firmicutes). The paucity of whole-genome data for Gram-positive methylotrophs limits our global understanding of methylotrophy within this group, including their roles in specific biogeochemical cycles, as well as their biotechnological potential. Here, we describe the isolation of seven novel strains of Gram-positive methylotrophs that include two strains of Bacillus and five representatives of Actinobacteria classified within two genera, Arthrobacter and Mycobacterium. We report whole-genome sequences for these isolates and present comparative analysis of the methylotrophy functional modules within these genomes. The genomic sequences of these seven novel organisms, all capable of growth on methylated amines, present an important reference dataset for understanding the genomic basis of methylotrophy in Gram-positive methylotrophic bacteria. This study is a major contribution to the field of methylotrophy, aimed at closing the gap in the genomic knowledge of methylotrophy within this diverse group of bacteria. PMID:27682081

Lignocellulolytic enzymes and bacteria associated with the digestive tracts of Stenochironomus (Diptera: Chironomidae) larvae.

PubMed

Koroiva, R; Souza, C W O; Toyama, D; Henrique-Silva, F; Fonseca-Gessner, A A

2013-04-02

We analyzed the digestive activity of the enzymes that digest cellulose and hemicellulose and the bacterial community that is capable of hydrolyzing wood compounds in the digestive tracts of Stenochironomus (Diptera: Chironomidae) larvae, which are miners of decomposing submerged tree and bush branches. Based on quantification of reducing sugars, these larvae have a limited capacity for cellulose degradation but a good capacity for xylan hydrolysis. We isolated 31 types of colonies from two larval morphotypes, of which 19 tested positive for the capacity to hydrolyze at least one of the four substrates that were used as the main carbon source in the culture media. Their woody compound degradation capacity was assessed using colorimetric tests. The bacteria were identified by the analysis of the 16S rRNA gene. None of the bacteria were capable of degrading lignin. The genus Pseudomonas had the greatest species richness; Bacillus spp exhibited the greatest capacity for degrading the different substrates, and Sphingobium was found in both morphotypes. Microorganisms participate in the degradation of wood consumed by Stenochironomus larvae. This is the first report of lignocellulolytic bacteria and enzymes in the digestive tracts of mining chironomids.

Endophytic occupation of root nodules and roots of Melilotus dentatus by Agrobacterium tumefaciens.

PubMed

Wang, Ling Ling; Wang, En Tao; Liu, Jie; Li, Ying; Chen, Wen Xin

2006-10-01

Agrobacterium strains have been frequently isolated from the root nodules of different legumes. Various possible mechanisms have been proposed to explain the existence of these bacteria in nodules, but there is no sufficient experimental evidence to support the estimations. In this work, we proved that the Agrobacterium strain CCBAU 81181, which was originally isolated from the root nodules of Onobrychis viciaefolia, and a symbiotic strain of Sinorhizobium meliloti CCBAU 10062 could coinhabit the root nodules of Melilotus dentatus. Analyses were performed by using a fluorescence marker, reisolation of bacteria from nodules, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole cellular proteins, and polymerase chain reaction amplification of symbiotic genes. The inoculation of A. tumefaciens CCBAU 81181 did not affect the growth and nodulation of plants. CCBAU 81181 and 24 other Agrobacterium strains isolated from nodules were incapable of nodulating on their original or alternative host and 22 strains of these strains were endophytes in the roots and stems of their hosts. Also, the tumor-inducing A. tumefaciens strains IAM 13129(T) and C58 were found capable of entering the roots of Glycyrrhiza pallidiflora, but did not cause pathogenic symptoms. With these results, we conclude that A. tumefaciens strains could be endophytic bacteria in the roots, stems, and root nodules. This finding partially explains why Agrobacterium strains were frequently isolated from the surface-sterilized nodules.

Accumulation of Citrulline by Microbial Arginine Metabolism during Alcoholic Fermentation of Soy Sauce.

PubMed

Fang, Fang; Zhang, Jiran; Zhou, Jingwen; Zhou, Zhaohui; Li, Tieqiao; Lu, Liling; Zeng, Weizhu; Du, Guocheng; Chen, Jian

2018-03-07

Citrulline, the major precursor of ethyl carbamate in soy sauce, is an intermediate catabolite of arginine produced by bacteria present in soy sauce moromi mash. Pediococcus acidilactici is responsible for the formation of citrulline during the lactic acid fermentation process of soy sauce. However, citrulline accumulation during the alcoholic fermentation process and the corresponding bacteria involved have not been identified. Salt-tolerant, arginine-utilizing bacteria were isolated from moromi mash during the alcoholic fermentation process. Under normal cultivation conditions, arginine utilization by these strains did not contribute to citrulline accumulation. However, the conversion of arginine to citrulline by these bacteria increased when cultivated during the alcoholic fermentation process. Additionally, the ethanol-enhanced solubility of free fatty acids in moromi mash stimulated the accumulation of citrulline. Staphylococcus exhibited the highest capability in the conversion of arginine to citrulline.

Isolation, identification and characterization of highly tellurite-resistant, tellurite-reducing bacteria from Antarctica

NASA Astrophysics Data System (ADS)

Arenas, Felipe A.; Pugin, Benoit; Henríquez, Nicole A.; Arenas-Salinas, Mauricio A.; Díaz-Vásquez, Waldo A.; Pozo, María F.; Muñoz, Claudia M.; Chasteen, Thomas G.; Pérez-Donoso, José M.; Vásquez, Claudio C.

2014-03-01

The tellurium oxyanion, tellurite, is extremely noxious to most living organisms. Its toxicity has been mainly related to the generation of reactive oxygen species (ROS) as well as to an unbalancing of the thiol:redox buffering system. Nevertheless, a few bacteria are capable of thriving at high tellurite concentrations. One mechanism of resistance is the enzymatic and non-enzymatic reduction of tellurite to the less toxic elemental tellurium. This reduction generates nano- to micrometric tellurium crystals that display different shapes and sizes. To date, a very limited number of highly tellurite-resistant and tellurite-reducing bacterial species are available from international culture collections. In this work, we decided to look for tellurite-reducing bacteria from an extreme environment, Antarctica. This environment exhibits a combination of several extreme factors such as high UV-radiation and desiccation and freezing conditions that impact directly on the local biodiversity. Since, as does, all these factors induce ROS formation, we hypothesized that Antarctic bacteria could also exhibit tellurite-resistance. In this context, we isolated 123 tellurite-resistant bacteria, and characterized six new tellurite-resistant and tellurite-reducing bacterial strains from samples collected in Antarctica. These strains were identified according to their 16S rRNA gene sequence as Staphylococcus hameolyticus, Staphylococcus sciuri, Acinetobacter haemolyticus, Pseudomonas lini, and two strains of Psychrobacter immobilis. The isolates display tellurite-resistance about 35- to 500-fold higher than Escherichia coli (Te-sensitive organism), and a high level of tellurite reduction which might be interesting for an application in the field of bioremediation or nanoparticle biosynthesis.

Development of Human Breast Milk Microbiota-Associated Mice as a Method to Identify Breast Milk Bacteria Capable of Colonizing Gut.

PubMed

Wang, Xiaoxin; Lu, Huifang; Feng, Zhou; Cao, Jie; Fang, Chao; Xu, Xianming; Zhao, Liping; Shen, Jian

2017-01-01

Human breast milk is recognized as one of multiple important sources of commensal bacteria for infant gut. Previous studies searched for the bacterial strains shared between breast milk and infant feces by isolating bacteria and performing strain-level bacterial genotyping, but only limited number of milk bacteria were identified to colonize infant gut, including bacteria from Bifidobacterium , Staphylococcus , Lactobacillus , and Escherichia / Shigella . Here, to identify the breast milk bacteria capable of colonizing gut without the interference of bacteria of origins other than the milk or the necessity to analyze infant feces, normal chow-fed germ-free mice were orally inoculated with the breast milk collected from a mother 2 days after vaginal delivery. According to 16S rRNA gene-based denaturant gradient gel electrophoresis and Illumina sequencing, bacteria at >1% abundance in the milk inoculum were only Streptococcus (56.0%) and Staphylococcus (37.4%), but in the feces of recipient mice were Streptococcus (80.3 ± 2.3%), Corynebacterium (10.0 ± 2.6 %), Staphylococcus (7.6 ± 1.6%), and Propionibacterium (2.1 ± 0.5%) that were previously shown as dominant bacterial genera in the meconium of C-section-delivered human babies; the abundance of anaerobic gut-associated bacteria, Faecalibacterium , Prevotella , Roseburia , Ruminococcus , and Bacteroides , was 0.01-1% in the milk inoculum and 0.003-0.01% in mouse feces; the abundance of Bifidobacterium spp. was below the detection limit of Illumina sequencing in the milk but at 0.003-0.01% in mouse feces. The human breast milk microbiota-associated mouse model may be used to identify additional breast milk bacteria that potentially colonize infant gut.

Draft Genome Sequence of the Obligately Alkaliphilic Sulfate-Reducing Bacterium Desulfonatronum thiodismutans Strain MLF1

PubMed Central

Trubitsyn, Denis; Geurink, Corey; Pikuta, Elena; Lefèvre, Christopher T.; McShan, W. Michael; Gillaspy, Allison F.

2014-01-01

Desulfonatronum thiodismutans strain MLF1, an alkaliphilic bacterium capable of sulfate reduction, was isolated from Mono Lake, California. Here we report the 3.92-Mb draft genome sequence comprising 34 contigs and some results of its automated annotation. These data will improve our knowledge of mechanisms by which bacteria withstand extreme environments. PMID:25081260

["Candidatus contubernalis alkalaceticum," an obligately syntrophic alkaliphilic bacterium capable of anaerobic acetate oxidation in a coculture with Desulfonatronum cooperativum].

PubMed

Zhilina, T N; Zavarzina, D G; Kolganova, T V; Turova, T P; Zavarzin, G A

2005-01-01

From the silty sediments of the Khadyn soda lake (Tuva), a binary sulfidogenic bacterial association capable of syntrophic acetate oxidation at pH 10.0 was isolated. An obligately syntrophic, gram-positive, spore-forming alkaliphilic rod-shaped bacterium performs acetate oxidation in a syntrophic association with a hydrogenotrophic, alkaliphilic sulfate-reducing bacterium; the latter organism was previously isolated and characterized as the new species Desulfonatronum cooperativum. Other sulfate-reducing bacteria of the genera Desulfonatronum and Desulfonatronovibrio can also act as the hydrogenotrophic partner. Apart from acetate, the syntrophic culture can oxidize ethanol, propanol, isopropanol, serine, fructose, and isobutyric acid. Selective amplification of 16S rRNA gene fragments of the acetate-utilizing syntrophic component of the binary culture was performed; it was found to cluster with clones of uncultured gram-positive bacteria within the family Syntrophomonadaceae. The acetate-oxidizing bacterium is thus the first representative of this cluster obtained in a laboratory culture. Based on its phylogenetic position, the new acetate-oxidizing syntrophic bacterium is proposed to be assigned, in a Candidate status, to a new genus and species: "Candidatus Contubernalis alkalaceticum."

Bacteria isolated from amoebae/bacteria consortium

DOEpatents

Tyndall, R.L.

1995-05-30

New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

Bacteria isolated from amoebae/bacteria consortium

DOEpatents

Tyndall, Richard L.

1995-01-01

New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

Isolation and Identification of Phyllospheric Bacteria Possessing Antimicrobial Activity from Astragalus obtusifolius, Prosopis juliflora, Xanthium strumarium and Hippocrepis unisiliqousa

PubMed Central

Mazinani, Zohreh; Zamani, Marzieh

2017-01-01

Background: The widespread utilization of antimicrobial compounds has caused emergence of resistant microorganisms in the world. Hence, the research to probe the products with antimicrobial features has led to finding natural habitats and discovering new pharmaceutical products. Methods: In this study, an attempt was made to explore the niche of novel habitat to isolate pyllospheric bacteria from the above ground parts (stems and leaves) of Astragalus obtusifolius, Prosopis juliflora, Xanthium strumarium, and Hippocrepis unisiliqousa to evaluate their antimicrobial features. The inhibitory effects of these strains on the growth of two fungi (Aspergillus niger, Aspergillus fumigatus), two yeasts (Saccharomyces cerevisiae, Candida albicans) and six bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella typhi, Streptococcus pyogenes) were tested. Results: In total, 113 bacterial strains were isolated. Twenty five bacterial strains (B-1 to B-25) indicated promising antimicrobial (antibacterial and antifungal) activities against aforementioned pathogens. The identification of the bacterial strains was ascertained by morphological, physiological, biochemical tests and two strains with the strongest antimicrobial activities were further characterized based on 16s rRNA sequencing. These two strains were identified as Bacillus amyloliquefaciens. Conclusion: Our results provide evidence that phyllospheric microorganisms are capable of producing some compounds with antimicrobial properties. PMID:28090278

Isolation and Identification of Phyllospheric Bacteria Possessing Antimicrobial Activity from Astragalus obtusifolius, Prosopis juliflora, Xanthium strumarium and Hippocrepis unisiliqousa.

PubMed

Mazinani, Zohreh; Zamani, Marzieh; Sardari, Soroush

2017-01-01

The widespread utilization of antimicrobial compounds has caused emergence of resistant microorganisms in the world. Hence, the research to probe the products with antimicrobial features has led to finding natural habitats and discovering new pharmaceutical products. In this study, an attempt was made to explore the niche of novel habitat to isolate pyllospheric bacteria from the above ground parts (stems and leaves) of Astragalus obtusifolius , Prosopis juliflora , Xanthium strumarium , and Hippocrepis unisiliqousa to evaluate their antimicrobial features. The inhibitory effects of these strains on the growth of two fungi ( Aspergillus niger , Aspergillus fumigatus ), two yeasts ( Saccharomyces cerevisiae , Candida albicans ) and six bacteria ( Escherichia coli , Staphylococcus aureus , Pseudomonas aeruginosa , Bacillus subtilis , Salmonella typhi , Streptococcus pyogenes ) were tested. In total, 113 bacterial strains were isolated. Twenty five bacterial strains (B-1 to B-25) indicated promising antimicrobial (antibacterial and antifungal) activities against aforementioned pathogens. The identification of the bacterial strains was ascertained by morphological, physiological, biochemical tests and two strains with the strongest antimicrobial activities were further characterized based on 16s rRNA sequencing. These two strains were identified as Bacillus amyloliquefaciens . Our results provide evidence that phyllospheric microorganisms are capable of producing some compounds with antimicrobial properties.

Characterization and antimicrobial spectrum of bacteriocins produced by lactic acid bacteria isolated from traditional Bulgarian dairy products.

PubMed

Simova, E D; Beshkova, D B; Dimitrov, Zh P

2009-02-01

To isolate bacteriocin-producing lactic acid bacteria (LAB) with high wide spectrum antibacterial activity and to characterize their inhibitory peptides. Seven LAB strains [Lactobacillus casei ssp. rhamnosus (PC5), Lactobacillus delbrueckii ssp. bulgaricus (BB18), Lactococcus lactis ssp. lactis (BCM5, BK15), Enterococcus faecium (MH3), Lactobacillus plantarum (BR12), Lactobacillus casei ssp. casei (BCZ2)], isolated from authentic Bulgarian dairy products were capable of producing bacteriocins, inhibiting the widest range of pathogenic bacteria. The bacteriocins were resistant to heating at 121 degrees C for 15 min, stable at pH 2-10, sensitive to protease, insensitive to alpha-amylase and lipase. Two of bacteriocins produced by Lact. bulgaricus BB18 (bulgaricin BB18) and E. faecium MH3 (enterocin MH3) were purified and the molecular masses were determined. The N-terminal amino acid sequence of bulgaricin BB18 did not show strong homology to other known bacteriocins. Lactobacillus bulgaricus BB18 and E. faecium MH3 produce two novel bacteriocins highly similar to the pediocin-like nonlantibiotics. The two bacteriocins are potential antimicrobial agents and, in conjunction with their producers, may have use in applications to contribute a positive effect on the balance of intestinal microflora. Furthermore, bulgaricin BB18 strongly inhibits Helicobacter pylori.

Biocatalytic desulfurization of thiophenic compounds and crude oil by newly isolated bacteria

PubMed Central

Mohamed, Magdy El-Said; Al-Yacoub, Zakariya H.; Vedakumar, John V.

2015-01-01

Microorganisms possess enormous highly specific metabolic activities, which enable them to utilize and transform nearly every known chemical class present in crude oil. In this context, one of the most studied biocatalytic processes is the biodesulfurization (BDS) of thiophenic sulfur-containing compounds such as benzothiophene (BT) and dibenzothiophene (DBT) in crude oils and refinery streams. Three newly isolated bacterial strains, which were affiliated as Rhodococcus sp. strain SA11, Stenotrophomonas sp. strain SA21, and Rhodococcus sp. strain SA31, were enriched from oil contaminated soil in the presence of DBT as the sole S source. GC-FID analysis of DBT-grown cultures showed consumption of DBT, transient formation of DBT sulfone (DBTO2) and accumulation of 2-hydroxybiphenyl (2-HBP). Molecular detection of the plasmid-borne dsz operon, which codes for the DBT desulfurization activity, revealed the presence of dszA, dszB, and dszC genes. These results point to the operation of the known 4S pathway in the BDS of DBT. The maximum consumption rate of DBT was 11 μmol/g dry cell weight (DCW)/h and the maximum formation rate of 2-HBP formation was 4 μmol/g DCW/h. Inhibition of both cell growth and DBT consumption by 2-HBP was observed for all isolates but SA11 isolate was the least affected. The isolated biocatalysts desulfurized other model DBT alkylated homologs. SA11 isolate was capable of desulfurizing BT as well. Resting cells of SA11 exhibited 10% reduction in total sulfur present in heavy crude oil and 18% reduction in total sulfur present in the hexane-soluble fraction of the heavy crude oil. The capabilities of the isolated bacteria to survive and desulfurize a wide range of S compounds present in crude oil are desirable traits for the development of a robust BDS biocatalyst to upgrade crude oils and refinery streams. PMID:25762990

Isolation and Characterization of Strains CVO and FWKO B, Two Novel Nitrate-Reducing, Sulfide-Oxidizing Bacteria Isolated from Oil Field Brine

PubMed Central

Gevertz, Diane; Telang, Anita J.; Voordouw, Gerrit; Jenneman, Gary E.

2000-01-01

Bacterial strains CVO and FWKO B were isolated from produced brine at the Coleville oil field in Saskatchewan, Canada. Both strains are obligate chemolithotrophs, with hydrogen, formate, and sulfide serving as the only known energy sources for FWKO B, whereas sulfide and elemental sulfur are the only known electron donors for CVO. Neither strain uses thiosulfate as an energy source. Both strains are microaerophiles (1% O2). In addition, CVO grows by denitrification of nitrate or nitrite whereas FWKO B reduces nitrate only to nitrite. Elemental sulfur is the sole product of sulfide oxidation by FWKO B, while CVO produces either elemental sulfur or sulfate, depending on the initial concentration of sulfide. Both strains are capable of growth under strictly autotrophic conditions, but CVO uses acetate as well as CO2 as its sole carbon source. Neither strain reduces sulfate; however, FWKO B reduces sulfur and displays chemolithoautotrophic growth in the presence of elemental sulfur, hydrogen, and CO2. Both strains grow at temperatures between 5 and 40°C. CVO is capable of growth at NaCl concentrations as high as 7%. The present 16s rRNA analysis suggests that both strains are members of the epsilon subdivision of the division Proteobacteria, with CVO most closely related to Thiomicrospira denitrifcans and FWKO B most closely related to members of the genus Arcobacter. The isolation of these two novel chemolithotrophic sulfur bacteria from oil field brine suggests the presence of a subterranean sulfur cycle driven entirely by hydrogen, carbon dioxide, and nitrate. PMID:10831429

Isolation, identification and diesel-oil biodegradation capacities of indigenous hydrocarbon-degrading strains of Cellulosimicrobium cellulans and Acinetobacter baumannii from tarball at Terengganu beach, Malaysia.

PubMed

Nkem, Bruno Martins; Halimoon, Normala; Yusoff, Fatimah Md; Johari, Wan Lufti Wan; Zakaria, Mohamad Pauzi; Medipally, Srikanth Reddy; Kannan, Narayanan

2016-06-15

In this study, we isolated two indigenous hydrocarbon-degrading bacteria from tarball found in Rhu Sepuluh beach, Terengganu, Malaysia. These bacteria were identified based on their physiological characteristic and 16S rRNA gene sequence analysis, and they showed 99% similarity with Cellulosimicrobium cellulans DSM 43879 and Acinetobacter baumannii ATCC 19606 respectively. Their hydrocarbon-degrading capabilities were tested using diesel-oil as sole carbon source. Results analysed using GC-MS, showed diesel-oil alkanes were degraded an average 64.4% by C. cellulans and 58.1% by A. baumannii with medium optical density reaching 0.967 (C. cellulans) and 1.515 (A. baumannii) in minimal salt media at 32°C for 10days. Individual diesel-oil alkanes were degraded between 10%-95.4% by C. cellulans and 0.2%-95.9% by A. baumannii. Both strains utilized diesel-oil for growth. The study suggests both strains are part of indigenous hydrocarbon-degrading bacteria in tarball with potential for bioremediation of oil-polluted marine environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterization and vaccine potential of outer membrane vesicles produced by Haemophilus parasuis

DOE PAGES

McCaig, William D.; Loving, Crystal L.; Hughes, Holly R.; ...

2016-03-01

Haemophilus parasuis is a Gram-negative bacterium that colonizes the upper respiratory tract of swine and is capable of causing a systemic infection, resulting in high morbidity and mortality. H. parasuis isolates display a wide range of virulence and virulence factors are largely unknown. Commercial bacterins are often used to vaccinate swine against H. parasuis, though strain variability and lack of cross-reactivity can make this an ineffective means of protection. Outer membrane vesicles (OMV) are spherical structures naturally released from the membrane of bacteria and OMV are often enriched in toxins, signaling molecules and other bacterial components. Examination of OMV structuresmore » has led to identification of virulence factors in a number of bacteria and they have been successfully used as subunit vaccines. We have isolated OMV from both virulent and avirulent strains of H. parasuis, have examined their protein content and assessed their ability to induce an immune response in the host. Lastly, vaccination with purified OMV derived from the virulent H. parasuis Nagasaki strain provided protection against challenge with a lethal dose of the bacteria.« less

Characterization and vaccine potential of outer membrane vesicles produced by Haemophilus parasuis

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCaig, William D.; Loving, Crystal L.; Hughes, Holly R.

Haemophilus parasuis is a Gram-negative bacterium that colonizes the upper respiratory tract of swine and is capable of causing a systemic infection, resulting in high morbidity and mortality. H. parasuis isolates display a wide range of virulence and virulence factors are largely unknown. Commercial bacterins are often used to vaccinate swine against H. parasuis, though strain variability and lack of cross-reactivity can make this an ineffective means of protection. Outer membrane vesicles (OMV) are spherical structures naturally released from the membrane of bacteria and OMV are often enriched in toxins, signaling molecules and other bacterial components. Examination of OMV structuresmore » has led to identification of virulence factors in a number of bacteria and they have been successfully used as subunit vaccines. We have isolated OMV from both virulent and avirulent strains of H. parasuis, have examined their protein content and assessed their ability to induce an immune response in the host. Lastly, vaccination with purified OMV derived from the virulent H. parasuis Nagasaki strain provided protection against challenge with a lethal dose of the bacteria.« less

Arsenite-oxidizing and arsenate-reducing bacteria associated with arsenic-rich groundwater in Taiwan

NASA Astrophysics Data System (ADS)

Liao, Vivian Hsiu-Chuan; Chu, Yu-Ju; Su, Yu-Chen; Hsiao, Sung-Yun; Wei, Chia-Cheng; Liu, Chen-Wuing; Liao, Chung-Min; Shen, Wei-Chiang; Chang, Fi-John

2011-04-01

Drinking highly arsenic-contaminated groundwater is a likely cause of blackfoot disease in Taiwan, but microorganisms that potentially control arsenic mobility in the subsurface remain unstudied. The objective of this study was to investigate the relevant arsenite-oxidizing and arsenate-reducing microbial community that exists in highly arsenic-contaminated groundwater in Taiwan. We cultured and identified arsenic-transforming bacteria, analyzed arsenic resistance and transformation, and determined the presence of genetic markers for arsenic transformation. In total, 11 arsenic-transforming bacterial strains with different colony morphologies and varying arsenic transformation abilities were isolated, including 10 facultative anaerobic arsenate-reducing bacteria and one strictly aerobic arsenite-oxidizing bacterium. All of the isolates exhibited high levels of arsenic resistance with minimum inhibitory concentrations of arsenic ranging from 2 to 200 mM. Strain AR-11 was able to rapidly oxidize arsenite to arsenate at concentrations relevant to environmental groundwater samples without the addition of any electron donors or acceptors. We provide evidence that arsenic-reduction activity may be conferred by the ars operon(s) that were not amplified by the designed primers currently in use. The 16S rRNA sequence analysis grouped the isolates into the following genera: Pseudomonas, Bacillus, Psychrobacter, Vibrio, Citrobacter, Enterobacter, and Bosea. Among these genera, we present the first report of the genus Psychrobacter being involved in arsenic reduction. Our results further support the hypothesis that bacteria capable of either oxidizing arsenite or reducing arsenate coexist and are ubiquitous in arsenic-contaminated groundwater.

Are leaf glandular trichomes of oregano hospitable habitats for bacterial growth?

PubMed

Karamanoli, K; Thalassinos, G; Karpouzas, D; Bosabalidis, A M; Vokou, D; Constantinidou, H-I

2012-05-01

Phyllospheric bacteria were isolated from microsites around essential-oil-containing glands of two oregano (Origanum vulgare subsp. hirtum) lines. These bacteria, 20 isolates in total, were subjected to bioassays to examine their growth potential in the presence of essential oils at different concentrations. Although there were qualitative and quantitative differences in the essential oil composition between the two oregano lines, no differences were recorded in their antibacterial activity. In disk diffusion bioassays, four of the isolated strains could grow almost unrestrained in the presence of oregano oil, another five proved very sensitive, and the remaining 11 showed intermediate sensitivity. The strain least inhibited by oregano essential oil was further identified by complete16s rRNA gene sequencing as Pseudomonas putida. It was capable of forming biofilms even in the presence of oregano oil at high concentrations. Resistance of P. putida to oregano oil was further elaborated by microwell dilution bioassays, and its topology on oregano leaves was studied by electron microscopy. When inoculated on intact oregano plants, P. putida was able not only to colonize sites adjacent to essential oil-containing glands, but even to grow intracellularly. This is the first time that such prolific bacterial growth inside the glands has been visually observed. Results of this study further revealed that several bacteria can be established on oregano leaves, suggesting that these bacteria have attributes that allow them to tolerate or benefit from oregano secondary metabolites.

The effects of bacteriophage and nanoparticles on microbial processes

NASA Astrophysics Data System (ADS)

Moody, Austin L.

There are approximately 1031 tailed phages in the biosphere, making them the most abundant organism. Bacteriophages are viruses that infect bacteria. Due to the large diversity and abundance, no two bacteriophages that have been isolated are genetically the same. Phage products have potential in disease therapy to solve bacteria-related problems, such as infections resulting from resistant strains of Staphylococcus aureus. A bacteriophage capable of infecting methicillin-resistant S. aureus (MRSA) was isolated from bovine hair. The bacteriophage, named JB phage, was characterized using purification, amplification, cesium chloride banding, scanning electron microscopy, and transmission electron microscopy. JB phage and nanoparticles were used in various in vitro and in vivo models to test their effects on microbial processes. Scanning and transmission electron microscopy studies revealed strong interactions between JB phage and nanoparticles, which resulted in increased bacteriophage infectivity. JB phage and nanoparticle cocktails were used as a therapeutic to treat skin and systemic infections in mice caused by MRSA.

Microbial biodegradation and toxicity of vinclozolin and its toxic metabolite 3,5-dichloroaniline.

PubMed

Lee, Jung-Bok; Sohn, Ho-Yong; Shin, Kee-Sun; Kim, Jong-Sik; Jo, Min-Sub; Jeon, Chun-Pyo; Jang, Jong-Ok; Kim, Jang-Eok; Kwon, Gi-Seok

2008-02-01

Vinclozolin, an endocrine disrupting chemical, is a chlorinated fungicide widely used to control fungal diseases. However, its metabolite 3,5-dichloroaniline is more toxic and persistent than the parent vinclozolin. For the biodegradation of vinclozolin, vinclozolin- and/or 3,5-dichloroaniline-degrading bacteria were isolated from pesticide-polluted agriculture soil. Among the isolated bacteria, a Rhodococcus sp. was identified from a 16S rDNA sequence analysis and named Rhodococcus sp. T1-1. The degradation ratios for vinclozolin or 3,5- dichloroaniline in a minimal medium containing vinclozolin (200 microg/ml) or 3,5-dichloroaniline (120 microg/ml) were 90% and 84.1%, respectively. Moreover, Rhodococcus sp. T1-1 also showed an effective capability to biodegrade dichloroaniline isomers on enrichment cultures in which they were contained. Therefore, these results suggest that Rhodococcus sp. T1-1 can bioremediate vinclozolin as well as 3,5-dichloroaniline.

Isolation and Identification of cellulolytic bacteria from mangrove sediment in Bangka Island

NASA Astrophysics Data System (ADS)

Kurniawan, A.; Prihanto, A. A.; Sari, S. P.; Febriyanti, D.; Kurniawan, A.; Sambah, A. B.; Asriani, E.

2018-04-01

Cellulolytic bacteria is bacteria which hydrolyze cellulose to reducing sugars. This research aims to obtain cellulolytic bacteria from the sediment of mangroves in Bangka island. Reasearch was conducted from March to August 2017. Sampling was conducted at Sungailiat, and Tukak Sadai, South of Bangka. Bacteria was isolated using 1% Carboxymetyl Cellulosa (CMC). The isolation resulted in four isolates from Sungailiat and nine isolates from Tukak Sadai. Total five isolates, namely Bacillus pumilus, Pseudomonas sp., Bacillus amyloliquefacien, Bacillus alvei, Bacillus coagulant were identified. The best isolates that produced cellulose was Pseudomonas aeruginosa.

Isolation of lactic acid bacteria from swine milk and characterization of potential probiotic strains with antagonistic effects against swine-associated gastrointestinal pathogens.

PubMed

Quilodrán-Vega, Sandra Rayén; Villena, Julio; Valdebenito, José; Salas, María José; Parra, Cristian; Ruiz, Alvaro; Kitazawa, Haruki; García, Apolinaria

2016-06-01

Probiotics are usually isolated from the gastrointestinal tract of humans and animals. The search of probiotics in human milk is a recent field of research, as the existence of the human milk microbiome was discovered only about a decade ago. To our knowledge, no reports regarding the potential probiotic effect of bacteria from swine milk have been published. In this work, we isolated several lactic acid bacteria from swine milk and evaluated them for them potential as probiotics. Among the isolated strains, Lactobacillus curvatus TUCO-5E showed antagonistic effects against swine-associated gastrointestinal pathogens. TUCO-5E was able to reduce the growth of enterotoxigenic and enterohemorrhagic Escherichia coli strains as well as pathogenic salmonella. In vitro exclusion and displacement assays in intestinal epithelial cells showed a remarkable antagonistic effect for L. curvatus TUCO-5E against Salmonella sp. strain TUCO-I7 and Salmonella enterica ATCC 13096. Moreover, by using a mouse model of Salmonella infection, we were able to demonstrate that preventative administration of L. curvatus TUCO-5E for 5 consecutive days was capable of decreasing the number of Salmonella enterica serovar Typhimurium in the liver and spleen of treated mice, compared with the controls, and prevented dissemination of the pathogen to the blood stream. Therefore, we have demonstrated here that swine milk is an interesting source of beneficial bacteria. In addition, the results of this work suggest that L. curvatus TUCO-5E is a good candidate to study in vivo the protective effect of probiotics against intestinal infection and damage induced by Salmonella infection in the porcine host.

Genome Sequence of the Verrucomicrobium Opitutus terrae PB90-1, an Abundant Inhabitant of Rice Paddy Soil Ecosystems▿

PubMed Central

van Passel, Mark W. J.; Kant, Ravi; Palva, Airi; Copeland, Alex; Lucas, Susan; Lapidus, Alla; Glavina del Rio, Tijana; Pitluck, Sam; Goltsman, Eugene; Clum, Alicia; Sun, Hui; Schmutz, Jeremy; Larimer, Frank W.; Land, Miriam L.; Hauser, Loren; Kyrpides, Nikolaos; Mikhailova, Natalia; Richardson, P. Paul; Janssen, Peter H.; de Vos, Willem M.; Smidt, Hauke

2011-01-01

Bacteria of the deeply branching phylum Verrucomicrobia are rarely cultured yet commonly detected in metagenomic libraries from aquatic, terrestrial, and intestinal environments. We have sequenced the genome of Opitutus terrae PB90-1, a fermentative anaerobe within this phylum, isolated from rice paddy soil and capable of propionate production from plant-derived polysaccharides. PMID:21398538

Draft Genome Sequence of the Obligately Alkaliphilic Sulfate-Reducing Bacterium Desulfonatronum thiodismutans Strain MLF1.

PubMed

Trubitsyn, Denis; Geurink, Corey; Pikuta, Elena; Lefèvre, Christopher T; McShan, W Michael; Gillaspy, Allison F; Bazylinski, Dennis A

2014-07-31

Desulfonatronum thiodismutans strain MLF1, an alkaliphilic bacterium capable of sulfate reduction, was isolated from Mono Lake, California. Here we report the 3.92-Mb draft genome sequence comprising 34 contigs and some results of its automated annotation. These data will improve our knowledge of mechanisms by which bacteria withstand extreme environments. Copyright © 2014 Trubitsyn et al.

Influences of Media Compositions on Characteristics of Isolated Bacteria Exhibiting Lignocellulolytic Activities from Various Environmental Sites.

PubMed

Gong, Gyeongtaek; Lee, Sun-Mi; Woo, Han Min; Park, Tai Hyun; Um, Youngsoon

2017-11-01

Efficient isolation of lignocellulolytic bacteria is essential for the utilization of lignocellulosic biomass. In this study, bacteria with cellulolytic, xylanolytic, and lignolytic activities were isolated from environmental sites such as mountain, wetland, and mudflat using isolation media containing the combination of lignocellulose components (cellulose, xylan, and lignin). Eighty-nine isolates from the isolation media were characterized by analyzing taxonomic ranks and cellulolytic, xylanolytic, and lignolytic activities. Most of the cellulolytic bacteria showed multienzymatic activities including xylanolytic activity. The isolation media without lignin were efficient in isolating bacteria exhibiting multienzymatic activities even including lignolytic activity, whereas a lignin-containing medium was effective to isolate bacteria exhibiting lignolytic activity only. Multienzymatic activities were mainly observed in Bacillus and Streptomyces, while Burkholderia was the most abundant genus with lignolytic activity only. This study provides insight into isolation medium for efficient isolation of lignocellulose-degrading microorganisms.

The Biodiversity of Lactic Acid Bacteria in Greek Traditional Wheat Sourdoughs Is Reflected in Both Composition and Metabolite Formation

PubMed Central

De Vuyst, Luc; Schrijvers, Vincent; Paramithiotis, Spiros; Hoste, Bart; Vancanneyt, Marc; Swings, Jean; Kalantzopoulos, George; Tsakalidou, Effie; Messens, Winy

2002-01-01

Lactic acid bacteria (LAB) were isolated from Greek traditional wheat sourdoughs manufactured without the addition of baker's yeast. Application of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total cell protein, randomly amplified polymorphic DNA-PCR, DNA-DNA hybridization, and 16S ribosomal DNA sequence analysis, in combination with physiological traits such as fructose fermentation and mannitol production, allowed us to classify the isolated bacteria into the species Lactobacillus sanfranciscensis, Lactobacillus brevis, Lactobacillus paralimentarius, and Weissella cibaria. This consortium seems to be unique for the Greek traditional wheat sourdoughs studied. Strains of the species W. cibaria have not been isolated from sourdoughs previously. No Lactobacillus pontis or Lactobacillus panis strains were found. An L. brevis-like isolate (ACA-DC 3411 t1) could not be identified properly and might be a new sourdough LAB species. In addition, fermentation capabilities associated with the LAB detected have been studied. During laboratory fermentations, all heterofermentative sourdough LAB strains produced lactic acid, acetic acid, and ethanol. Mannitol was produced from fructose that served as an additional electron acceptor. In addition to glucose, almost all of the LAB isolates fermented maltose, while fructose as the sole carbohydrate source was fermented by all sourdough LAB tested except L. sanfranciscensis. Two of the L. paralimentarius isolates tested did not ferment maltose; all strains were homofermentative. In the presence of both maltose and fructose in the medium, induction of hexokinase activity occurred in all sourdough LAB species mentioned above, explaining why no glucose accumulation was found extracellularly. No maltose phosphorylase activity was found either. These data produced a variable fermentation coefficient and a unique sourdough metabolite composition. PMID:12450829

The biodiversity of lactic acid bacteria in Greek traditional wheat sourdoughs is reflected in both composition and metabolite formation.

PubMed

De Vuyst, Luc; Schrijvers, Vincent; Paramithiotis, Spiros; Hoste, Bart; Vancanneyt, Marc; Swings, Jean; Kalantzopoulos, George; Tsakalidou, Effie; Messens, Winy

2002-12-01

Lactic acid bacteria (LAB) were isolated from Greek traditional wheat sourdoughs manufactured without the addition of baker's yeast. Application of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total cell protein, randomly amplified polymorphic DNA-PCR, DNA-DNA hybridization, and 16S ribosomal DNA sequence analysis, in combination with physiological traits such as fructose fermentation and mannitol production, allowed us to classify the isolated bacteria into the species Lactobacillus sanfranciscensis, Lactobacillus brevis, Lactobacillus paralimentarius, and Weissella cibaria. This consortium seems to be unique for the Greek traditional wheat sourdoughs studied. Strains of the species W. cibaria have not been isolated from sourdoughs previously. No Lactobacillus pontis or Lactobacillus panis strains were found. An L. brevis-like isolate (ACA-DC 3411 t1) could not be identified properly and might be a new sourdough LAB species. In addition, fermentation capabilities associated with the LAB detected have been studied. During laboratory fermentations, all heterofermentative sourdough LAB strains produced lactic acid, acetic acid, and ethanol. Mannitol was produced from fructose that served as an additional electron acceptor. In addition to glucose, almost all of the LAB isolates fermented maltose, while fructose as the sole carbohydrate source was fermented by all sourdough LAB tested except L. sanfranciscensis. Two of the L. paralimentarius isolates tested did not ferment maltose; all strains were homofermentative. In the presence of both maltose and fructose in the medium, induction of hexokinase activity occurred in all sourdough LAB species mentioned above, explaining why no glucose accumulation was found extracellularly. No maltose phosphorylase activity was found either. These data produced a variable fermentation coefficient and a unique sourdough metabolite composition.

The Gastrointestinal Tract of the White-Throated Woodrat (Neotoma albigula) Harbors Distinct Consortia of Oxalate-Degrading Bacteria

PubMed Central

Kohl, Kevin D.; Dearing, M. Denise

2014-01-01

The microbiota inhabiting the mammalian gut is a functional organ that provides a number of services for the host. One factor that may regulate the composition and function of gut microbial communities is dietary toxins. Oxalate is a toxic plant secondary compound (PSC) produced in all major taxa of vascular plants and is consumed by a variety of animals. The mammalian herbivore Neotoma albigula is capable of consuming and degrading large quantities of dietary oxalate. We isolated and characterized oxalate-degrading bacteria from the gut contents of wild-caught animals and used high-throughput sequencing to determine the distribution of potential oxalate-degrading taxa along the gastrointestinal tract. Isolates spanned three genera: Lactobacillus, Clostridium, and Enterococcus. Over half of the isolates exhibited significant oxalate degradation in vitro, and all Lactobacillus isolates contained the oxc gene, one of the genes responsible for oxalate degradation. Although diverse potential oxalate-degrading genera were distributed throughout the gastrointestinal tract, they were most concentrated in the foregut, where dietary oxalate first enters the gastrointestinal tract. We hypothesize that unique environmental conditions present in each gut region provide diverse niches that select for particular functional taxa and communities. PMID:24362432

Degradation of 2,4,6-Trinitrophenol (TNP) by Arthrobacter sp. HPC1223 Isolated from Effluent Treatment Plant.

PubMed

Qureshi, Asifa; Kapley, Atya; Purohit, Hemant J

2012-12-01

Arthrobacter sp. HPC1223 (Genebank Accession No. AY948280) isolated from activated biomass of effluent treatment plant was capable of utilizing 2,4,6 trinitrophenol (TNP) under aerobic condition at 30 °C and pH 7 as nitrogen source. It was observed that the isolated bacteria utilized TNP up to 70 % (1 mM) in R2A media with nitrite release. The culture growth media changed into orange-red color hydride-meisenheimer complex at 24 h as detected by HPLC. Oxygen uptake of Arthrobacter HPC1223 towards various nitro/amino substituted phenols such as dinitrophenol (1.2 nmol/min/mg cells), paranitrophenol (0.9 nmol/min/mg cells), 2-aminophenol (0.75 nmol/min/mg cells), p-aminophenol (0.4 nmol/min/mg cells), phenol (0.56 nmol/min/mg cells) and TNP (2.42 nmol/min/mg cell) was analysed, which showed its additional characteristic of broad substrate catabolic capacity. The present study thus report a novel indigenous bacteria isolated from activated sludge utilized TNP and has broad catabolic potential towards substituted phenols.

Determination of metabolites of diosmetin-7-O-glucoside by a newly isolated Escherichia coli from human gut using UPLC-Q-TOF/MS.

PubMed

Zhao, Min; Du, Leyue; Tao, Jinhua; Qian, Dawei; Shang, Er-xin; Jiang, Shu; Guo, Jianming; Liu, Pei; Su, Shu-lan; Duan, Jin-ao

2014-11-26

Different human intestinal bacteria were isolated and screened for their ability to transform diosmetin-7-O-glucoside. A Gram-negative anaerobic bacterium, strain 4, capable of metabolizing diosmetin-7-O-glucoside was newly isolated. Its 16S rRNA gene sequence displayed 99% similarity with that of Escherichia. Then strain 4 was identified as a species of the genus Escherichia and was named Escherichia sp. 4. Additionally, an ultraperformance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technique combined with Metabolynx software method was established to screen the metabolites of diosmetin-7-O-glucoside. Comparing the retention time and MS/MS spectrum, three metabolites were detected and tentatively identified. These metabolites were acquired by four proposed metabolic pathways including dehydroxylation, deglycosylation, methylation, and acetylation. Diosmetin-7-O-glucoside was mainly bioconverted to considerable amounts of diosmetin and minor amounts of acacetin by the majority of the isolated intestinal bacteria such as Escherichia sp. 4. Subsequently, several strains could degrade acacetin to produce methylated and acetylated acacetin. The metabolites and metabolic pathways of diosmetin-7-O-glucoside by human intestinal bacterium Escherichia sp. 4 were first investigated.

The histamine content of dried flying fish products in Taiwan and the isolation of halotolerant histamine-forming bacteria.

PubMed

Kung, Hsien-Feng; Huang, Chun-Yung; Lin, Chia-Min; Liaw, Lon-Hsiu; Lee, Yi-Chen; Tsai, Yung-Hsiang

2015-06-01

Thirty dried flying fish products were purchased from fishing village stores in Taiwan and tested to detect the presence of histamine and histamine-forming bacteria. Except for histamine and cadaverine, the average content of various biogenic amines in the tested samples was less than 3.5 mg/100 g. Eight (26.6%) dried flying fish samples had histamine levels greater than the United States Food and Drug Administration guideline of 5 mg/100 g for scombroid fish and/or scombroid products, whereas four (13.3%) samples contained more than the hazard action level of 50 mg/100 g. One histamine-producing bacterial isolate was identified as Staphylococcus xylosus by 16S rDNA sequencing with polymerase chain reaction amplification. This isolate was capable of producing 507.8 ppm of histamine in trypticase soy broth supplemented with 1.0% l-histidine (TSBH). The S. xylosus isolate was a halotolerant bacterium that had a consistent ability to produce more than 300 ppm of histamine at 3% sodium chloride concentration in TSBH medium after 72 hours. Copyright © 2015. Published by Elsevier B.V.

Prodigiosin, Violacein, and Volatile Organic Compounds Produced by Widespread Cutaneous Bacteria of Amphibians Can Inhibit Two Batrachochytrium Fungal Pathogens.

PubMed

Woodhams, Douglas C; LaBumbard, Brandon C; Barnhart, Kelly L; Becker, Matthew H; Bletz, Molly C; Escobar, Laura A; Flechas, Sandra V; Forman, Megan E; Iannetta, Anthony A; Joyce, Maureen D; Rabemananjara, Falitiana; Gratwicke, Brian; Vences, Miguel; Minbiole, Kevin P C

2018-05-01

Symbiotic bacteria can produce secondary metabolites and volatile compounds that contribute to amphibian skin defense. Some of these symbionts have been used as probiotics to treat or prevent the emerging disease chytridiomycosis. We examined 20 amphibian cutaneous bacteria for the production of prodigiosin or violacein, brightly colored defense compounds that pigment the bacteria and have characteristic spectroscopic properties making them readily detectable, and evaluated the antifungal activity of these compounds. We detected violacein from all six isolates of Janthinobacterium lividum on frogs from the USA, Switzerland, and on captive frogs originally from Panama. We detected prodigiosin from five isolates of Serratia plymuthica or S. marcescens, but not from four isolates of S. fonticola or S. liquefaciens. All J. lividum isolates produced violacein when visibly purple, while prodigiosin was only detected on visibly red Serratia isolates. When applied to cultures of chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), prodigiosin caused significant growth inhibition, with minimal inhibitory concentrations (MIC) of 10 and 50 μM, respectively. Violacein showed a MIC of 15 μM against both fungi and was slightly more active against Bsal than Bd at lower concentrations. Although neither violacein nor prodigiosin showed aerosol activity and is not considered a volatile organic compound (VOC), J. lividum and several Serratia isolates did produce antifungal VOCs. White Serratia isolates with undetectable prodigiosin levels could still inhibit Bd growth indicating additional antifungal compounds in their chemical arsenals. Similarly, J. lividum can produce antifungal compounds such as indole-3-carboxaldehyde in addition to violacein, and isolates are not always purple, or turn purple under certain growth conditions. When Serratia isolates were grown in the presence of cell-free supernatant (CFS) from the fungi, CFS from Bd inhibited growth of the prodigiosin-producing isolates, perhaps indicative of an evolutionary arms race; Bsal CFS did not inhibit bacterial growth. In contrast, growth of one J. lividum isolate was facilitated by CFS from both fungi. Isolates that grow and continue to produce antifungal compounds in the presence of pathogens may represent promising probiotics for amphibians infected or at risk of chytridiomycosis. In a global analysis, 89% of tested Serratia isolates and 82% of J. lividum isolates were capable of inhibiting Bd and these have been reported from anurans and caudates from five continents, indicating their widespread distribution and potential for host benefit.

Biodegradation of Tributyltin (TBT) by Extremophile Bacteria from Atacama Desert and Speciation of Tin By-products.

PubMed

Yáñez, Jorge; Riffo, Paula; Santander, Paola; Mansilla, Héctor D; Mondaca, María Angélica; Campos, Víctor; Amarasiriwardena, Dulasiri

2015-07-01

Biodegradation of tributyltin (TBT) by four tin resistant Gram negative bacteria isolated from extremely contaminated river sediments in the Atacama Desert in Chile was studied. Moraxella osloensis showed the greatest resistance and degradation capability of TBT, producing less toxic by-products, such as dibutyltin (DBT) and inorganic tin. In 7 days, approximately 80 % of TBT degradation was achieved, generating close to 20 % of DBT as degradation product. The degradation rate constant (k) was 0.022 [day(-1)] and TBT half-life (t1/2) in culture was 4.3 days. Debutylation is stated a probable mechanism of TBT degradation.

Potential for plant growth promotion by a consortium of stress-tolerant 2,4-dinitrotoluene-degrading bacteria: isolation and characterization of a military soil

PubMed Central

Thijs, Sofie; Weyens, Nele; Sillen, Wouter; Gkorezis, Panagiotis; Carleer, Robert; Vangronsveld, Jaco

2014-01-01

The presence of explosives in soils and the interaction with drought stress and nutrient limitation are among the environmental factors that severely affect plant growth on military soils. In this study, we seek to isolate and identify the cultivable bacteria of a 2,4-dinitrotoluene (DNT) contaminated soil (DS) and an adjacent grassland soil (GS) of a military training area aiming to isolate new plant growth-promoting (PGP) and 2,4-DNT-degrading strains. Metabolic profiling revealed disturbances in Ecocarbon use in the bare DS; isolation of cultivable strains revealed a lower colony-forming-unit count and a less diverse community associated with DS in comparison with GS. New 2,4-DNT-tolerant strains were identified by selective enrichments, which were further characterized by auxanography for 2,4-DNT use, resistance to drought stress, cold, nutrient starvation and PGP features. By selecting multiple beneficial PGP and abiotic stress-resistant strains, efficient 2,4-DNT-degrading consortia were composed. After inoculation, consortium UHasselt Sofie 3 with seven members belonging to Burkholderia, Variovorax, Bacillus, Pseudomonas and Ralstonia species was capable to successfully enhance root length of Arabidopsis under 2,4-DNT stress. After 9 days, doubling of main root length was observed. Our results indicate that beneficial bacteria inhabiting a disturbed environment have the potential to improve plant growth and alleviate 2,4-DNT stress. PMID:24467368

Isolation of Soil Bacteria Adapted To Degrade Humic Acid-Sorbed Phenanthrene

PubMed Central

Vacca, D. J.; Bleam, W. F.; Hickey, W. J.

2005-01-01

The goal of these studies was to determine how sorption by humic acids affected the bioavailability of polynuclear aromatic hydrocarbons (PAHs) to PAH-degrading microbes. Micellar solutions of humic acid were used as sorbents, and phenanthrene was used as a model PAH. Enrichments from PAH-contaminated soils established with nonsorbed phenanthrene yielded a total of 25 different isolates representing a diversity of bacterial phylotypes. In contrast, only three strains of Burkholderia spp. and one strain each of Delftia sp. and Sphingomonas sp. were isolated from enrichments with humic acid-sorbed phenanthrene (HASP). Using [14C]phenanthrene as a radiotracer, we verified that only HASP isolates were capable of mineralizing HASP, a phenotype hence termed “competence.” Competence was an all-or-nothing phenotype: noncompetent strains showed no detectable phenanthrene mineralization in HASP cultures, but levels of phenanthrene mineralization effected by competent strains in HASP and NSP cultures were not significantly different. Levels and rates of phenanthrene mineralization exceeded those predicted to be supported solely by the metabolism of phenanthrene in the aqueous phase of HASP cultures. Thus, competent strains were able to directly access phenanthrene sorbed by the humic acids and did not rely on desorption for substrate uptake. To the best of our knowledge, this is the first report of (i) a selective interaction between aerobic bacteria and humic acid molecules and (ii) differential bioavailability to bacteria of PAHs sorbed to a natural biogeopolymer. PMID:16000791

Potential for plant growth promotion by a consortium of stress-tolerant 2,4-dinitrotoluene-degrading bacteria: isolation and characterization of a military soil.

PubMed

Thijs, Sofie; Weyens, Nele; Sillen, Wouter; Gkorezis, Panagiotis; Carleer, Robert; Vangronsveld, Jaco

2014-07-01

The presence of explosives in soils and the interaction with drought stress and nutrient limitation are among the environmental factors that severely affect plant growth on military soils. In this study, we seek to isolate and identify the cultivable bacteria of a 2,4-dinitrotoluene (DNT) contaminated soil (DS) and an adjacent grassland soil (GS) of a military training area aiming to isolate new plant growth-promoting (PGP) and 2,4-DNT-degrading strains. Metabolic profiling revealed disturbances in Ecocarbon use in the bare DS; isolation of cultivable strains revealed a lower colony-forming-unit count and a less diverse community associated with DS in comparison with GS. New 2,4-DNT-tolerant strains were identified by selective enrichments, which were further characterized by auxanography for 2,4-DNT use, resistance to drought stress, cold, nutrient starvation and PGP features. By selecting multiple beneficial PGP and abiotic stress-resistant strains, efficient 2,4-DNT-degrading consortia were composed. After inoculation, consortium UHasselt Sofie 3 with seven members belonging to Burkholderia, Variovorax, Bacillus, Pseudomonas and Ralstonia species was capable to successfully enhance root length of Arabidopsis under 2,4-DNT stress. After 9 days, doubling of main root length was observed. Our results indicate that beneficial bacteria inhabiting a disturbed environment have the potential to improve plant growth and alleviate 2,4-DNT stress. © 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Screening of species-specific lactic acid bacteria for veal calves multi-strain probiotic adjuncts.

PubMed

Ripamonti, Barbara; Agazzi, Alessandro; Bersani, Carla; De Dea, Paola; Pecorini, Chiara; Pirani, Silvia; Rebucci, Raffaella; Savoini, Giovanni; Stella, Simone; Stenico, Alberta; Tirloni, Erica; Domeneghini, Cinzia

2011-06-01

The selection of promising specific species of lactic acid bacteria with potential probiotic characteristics is of particular interest in producing multi species-specific probiotic adjuncts in veal calves rearing. The aim of the present work was to select and evaluate in vitro the functional activity of lactic acid bacteria, Bifidobacterium longum and Bacillus coagulans strains isolated from veal calves in order to assess their potential use as multi species-specific probiotics for veal calves. For this purpose, bacterial strains isolated from faeces collected from 40 healthy 50-day-calves, were identified by RiboPrinter and 16s rRNA gene sequence. The most frequent strains belonged to the species B. longum, Streptococcus bovis, Lactobacillus animalis and Streptococcus macedonicus. Among these, 7 strains were chosen for testing their probiotic characteristics in vitro. Three strains, namely L. animalis SB310, Lactobacillus paracasei subsp. paracasei SB137 and B. coagulans SB117 showed varying individual but promising capabilities to survive in the gastrointestinal tract, to adhere, to produce antimicrobial compounds. These three selected species-specific bacteria demonstrated in vitro, both singularly and mixed, the functional properties needed for their use as potential probiotics in veal calves. Copyright © 2011 Elsevier Ltd. All rights reserved.

A Glutamic Acid-Producing Lactic Acid Bacteria Isolated from Malaysian Fermented Foods

PubMed Central

Zareian, Mohsen; Ebrahimpour, Afshin; Bakar, Fatimah Abu; Mohamed, Abdul Karim Sabo; Forghani, Bita; Ab-Kadir, Mohd Safuan B.; Saari, Nazamid

2012-01-01

l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA) as a bioactive compound. PMID:22754309

Isolation, identification, and environmental adaptability of heavy-metal-resistant bacteria from ramie rhizosphere soil around mine refinery.

PubMed

Jiang, Jie; Pan, Chaohu; Xiao, Aiping; Yang, Xiai; Zhang, Guimin

2017-05-01

Six bacteria strains from heavy-metal-polluted ramie rhizosphere soil were isolated through Cd 2+ stress, which were numbered as JJ1, JJ2, JJ10, JJ11, JJ15, and JJ18. Sequence alignment and phylogenic analysis showed that strain JJ1 belonged to Pseudomonas, strain JJ2 belonged to Cupriavidus, strains JJ11 and JJ15 belonged to Bacillus, and strains JJ10 and JJ18 belonged to Acinetobacter. The tolerance capability of all the strains was the trend of Pb 2+  > Zn 2+  > Cu 2+  > Cd 2+ , the maximum tolerance concentration to Cd 2+ was 200 mg/L, to Pb 2+ was 1600 mg/L, to Zn 2+ was 600 mg/L, and to Cu 2+ was 265 mg/L. Strains JJ1, JJ11, JJ15, and JJ18 could grow well under pH 9.0, and strains JJ2, JJ11, and JJ18 could grow well under 7% of NaCl. The results showed that as a whole these strains had high environmental adaptability. This is the first report that heavy-metal-tolerant bacteria were found from ramie rhizosphere soil, which could be as a foundation to discover the relationship between ramie, rhizosphere bacteria and heavy metals.

Isolation and characterization of marine bacteria from macroalgae Gracilaria salicornia and Gelidium latifolium on agarolitic activity for bioethanol production

NASA Astrophysics Data System (ADS)

Kawaroe, M.; Pratiwi, I.; Sunudin, A.

2017-05-01

Gracilaria salicornia and Gelidium latifolium have high content of agar and potential to be use as raw material for bioethanol. In bioethanol production, one of the processes level is enzyme hydrolysis. Various microorganisms, one of which is bacteria, can carry out the enzyme hydrolysis. Bacteria that degrade the cell walls of macroalgae and produce an agarase enzyme called agarolytic bacteria. The purpose of this study was to isolate bacteria from macroalgae G. salicornia and G. latifolium, which has the highest agarase enzyme activities, and to obtain agarase enzyme characteristic for bioethanol production. There are two isolates bacteria resulted from G. salicornia that are N1 and N3 and there are two isolates from G. latifolium that are BSUC2 and BSUC4. The result of agarase enzyme qualitative test showed that isolates bacteria from G. latifolium were greater than G. salicornia. The highest agarolitic index of bacteria from G. salicornia produced by isolate N3 was 2.32 mm and isolate N3 was 2.27 mm. Bacteria from G. latifolium produced by isolate BSUC4 was 4.28 mm and isolate BSUC2 was 4.18 mm, respectively. Agarase enzyme activities from isolates N1 and N3 were optimum working at pH 7 and temperature 30 °C, while from isolates BSUC4 was optimum at pH 7 and temperature 50 °C. This is indicated that the four bacteria are appropriate to hydrolyze macro alga for bioethanol production.

Isolation of iron bacteria from terrestrial and aquatic environments

NASA Astrophysics Data System (ADS)

Schmidt, Bertram; Szewzyk, Ulrich

2010-05-01

Bacteria, which are capable of iron oxidation or at least iron deposition are widely distributed in environments where zones of dissolved ferrous iron and oxygen gradients are overlapping [1]. They take part in the biological cycling of iron and influence other cycles of elements for example carbon [2]. Manganese can be used for similar metabolic purposes as iron, because it can be biologically oxidized by chemolithotrophs or can be reduced by respirating bacteria as well [3, 4]. Bacterial activity is responsible for the accumulation of ferric iron compounds in their surroundings. The formation of bog ore is a well known example for a soil horizon, with an extreme enrichment of biogenic ferric iron [5]. We focused on the isolation of neutrophilic iron bacteria and bacteria capable of manganese oxidation. We used samples from Tierra del Fuego (Argentina) the National Park "Unteres Odertal" (Germany) and Berlin ground water wells. Microscopic examination of the samples revealed a considerable diversity of iron encrusted structures of bacterial origin. Most of these morphologic types are already well known. The taxonomic classification of many of these organisms is based on morphologic features and is not reliable compared to recent methods of molecular biology. That is mainly due to the fact, that most of these bacteria are hardly culturable or do not show their characteristic morphologic features under culture conditions. We established a collection of more than 300 iron depositing strains. Phylogenetic analyses showed that we have many yet uncultured strains in pure culture. We obtained many isolates which form distinct branches within long known iron bacteria groups like the Sphaerotilus-Leptothrix cluster. But some of the strains belong to groups, which have not yet been associated with iron oxidation activity. The strains deposit high amounts of oxidized iron and manganese compounds under laboratory conditions. However it is unclear if these precipitations are due to biological oxidation or biological deposition of chemically oxidized iron. We examined the morphologic characteristics of selected isolates under near-natural conditions to assign them to morphologic structures which occur in native samples. Our aim for the future is to describe several strains. References: [1] Weber, K. A. ; Achenbach, L. A. ; Coates, J. D. : Microorganisms pumping iron: anaerobic microbial iron oxidation and reduction. In: Nature Reviews Microbiology 4 (2006) 752-764 [2] Van Capellen, P. ; Wang Y. : Cycling of iron and manganese in surface sediments: a general theory for the coupled transport and reaction of carbon, oxygen, nitrogen, sulfur, iron and manganese. In: American Journal of Science 296 (1996) 197-243 [3] Tebo, B. M. ; Bargar, J. R. ; Clement, B. G. ; Dick, G. J. ; Murray, K. J. ; Parker, D. Verity R. ; Webb, S. M. : Biogenic manganese oxides: properties and mechanisms of formation. In: Annual Reviews Earth Planet Science 32 (2004) 287-328 [4] Erlich, H. L. : Manganese oxide reduction as a form of anaerobic respiration. In: Geomicrobiology Journal 5 (1987) 423-431 [5] Ghiorse W. C. : Biology of iron- and manganese-depositing bacteria. In: Annual Reviews 38 (1984) 515-550

The Effectiveness of Heterotrophic Bacteria Isolated from Dumai Marine Waters of Riau, Used as Antibacterial against Pathogens in Fish Culture

NASA Astrophysics Data System (ADS)

Feliatra, F.; Nursyirwani; Tanjung, A.; Adithiya, DS; Susanna, M.; Lukystyowati, I.

2018-02-01

Heterotrophic bacteria have an important role as decomposer of organic compounds (mineralization) derived from industrial waste, decomposition of unconsumed feed, faecal, excretion of fish, and have the ability to inhibit the growth of pathogenic bacteria. We investigated the role of heterotrophic bacteria used as antibacterial against pathogens in fish culture.This research was conducted from January until March 2017. The phylogenitic of the isolated bacterial was determined by 16S rDNA sequences analysis. Antagonism test showed that the bacteria had the ability to inhibit the growth of pathogenic bacteria (Vibrio alginolyticus, Aeromonas hydrophila and Pseudomonas sp.) Three isolates (Dm5, Dm6 and Dm4) indicated high inhibition zones which were classified into strong category with the average from 10.5 to 11.8 mm toward V. alginolitycus. Other isolates were classified into medium and weak category. Based on DNA analysis of heterotrophic bacteria isolated from marine waters of industrial area and low salinity of estuarine waters twelve strains of bacteria were identified, and all had highest level of homology to Bacillus sp.,one isolates has similarity to Enterobacter cloacae, other isolates to Clostridium cetobutylicum. Most of isolated bacteria obtained from the waters of industrial area due to it received much of nutrients that very influenced the growth of bacteria.

Enhancing methyl parathion degradation by the immobilization of Burkholderia sp. isolated from agricultural soils.

PubMed

Fernández-López, Maikel Gilberto; Popoca-Ursino, Carolina; Sánchez-Salinas, Enrique; Tinoco-Valencia, Raunel; Folch-Mallol, Jorge Luis; Dantán-González, Edgar; Laura Ortiz-Hernández, Ma

2017-10-01

Organophosphate pesticides are of great interest for research because they are currently the most commonly used pesticides. In this study, a bacterial strain capable of completely degrading methyl parathion (MP) was isolated from agricultural soils in central Mexico. This strain was designated strain S5-2 and was identified as Burkholderia cenocepacia. To increase degradation yields, cells were immobilized on three different supports: powdered zeolite and Opuntia sp. and Agave sp. fibers. The results indicated a significant increase in MP hydrolysis and p-nitrophenol (PNP) degradation with immobilized cells compared to free cell cultures. Furthermore, immobilized cells were capable of withstanding and degrading higher concentrations of PNP compared to cell suspension cultures. The cell viability in the free cell cultures, as well as PNP degradation, was affected at concentrations greater than 25 mg/L. In contrast, cells immobilized on Opuntia sp. and Agave sp. fibers completely degraded PNP at concentrations of 100 mg/L. To verify that MP solution toxicity was decreased by B. cenocepacia strain S5-2 via pesticide degradation, we measured the acetylcholinesterase activity, both before and after treatment with bacteria. The results demonstrate that the activity of acetylcholinesterase was unaffected after MP degradation by bacteria. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Effective remediation of fish processing waste using mixed culture biofilms capable of simultaneous nitrification and denitrification.

PubMed

Markande, Anoop R; Kapagunta, Chandrika; Patil, Pooja S; Nayak, Binaya B

2016-09-01

Fish processing waste water causes pollution and eutrophication of water bodies when released untreated. Use of bacteria capable of simultaneous nitrification and denitrification (SND) as biofilms on carriers in a moving bed bioreactor (MBBR) is a popular approach but seldom used for fish processing waste water remediation. Here, we studied the variations in biofilm formation and application activities by isolates Lysinibacillus sp. HT13, Alcaligenes sp. HT15 and Proteus sp. HT37 previously reported by us. While HT13 and HT15 formed significantly higher biofilms in polystyrene microtitre plates than on carriers, HT37 exhibited highest on carriers. A consortium of the three selected bacteria grown as biofilm on MBBR carriers exhibited better remediation of ammonia (200-600 ppm and 50 mM) than the individual isolates on carriers. The mixed biofilm set on the carriers was used for nitrogenous waste removal from fish processing waste water in 2 and 20 L setups. The total nitrogen estimated by elemental analysis showed complete remediation from 250 ppm in both 2 and 20 L waste water systems within 48 h. The usual toxic nitrogenous components-ammonia, nitrite and nitrate were also remediated efficiently. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diversity and Ubiquity of Bacteria Capable of Utilizing Humic Substances as Electron Donors for Anaerobic Respiration

PubMed Central

Coates, John D.; Cole, Kimberly A.; Chakraborty, Romy; O'Connor, Susan M.; Achenbach, Laurie A.

2002-01-01

Previous studies have demonstrated that reduced humic substances (HS) can be reoxidized by anaerobic bacteria such as Geobacter, Geothrix, and Wolinella species with a suitable electron acceptor; however, little is known of the importance of this metabolism in the environment. Recently we investigated this metabolism in a diversity of environments including marine and aquatic sediments, forest soils, and drainage ditch soils. Most-probable-number enumeration studies were performed using 2,6-anthrahydroquinone disulfonate (AHDS), an analog for reduced HS, as the electron donor with nitrate as the electron acceptor. Anaerobic organisms capable of utilizing reduced HS as an electron donor were found in all environments tested and ranged from a low of 2.31 × 101 in aquifer sediments to a high of 9.33 × 106 in lake sediments. As part of this study we isolated six novel organisms capable of anaerobic AHDS oxidation. All of the isolates coupled the oxidation of AHDS to the reduction of nitrate with acetate (0.1 mM) as the carbon source. In the absence of cells, no AHDS oxidation was apparent, and in the absence of AHDS, no cell density increase was observed. Generally, nitrate was reduced to N2. Analysis of the AHDS and its oxidized form, 2,6-anthraquinone disulfonate (AQDS), in the medium during growth revealed that the anthraquinone was not being biodegraded as a carbon source and was simply being oxidized as an energy source. Determination of the AHDS oxidized and nitrate reduced accounted for 109% of the theoretical electron transfer. In addition to AHDS, all of these isolates could also couple the oxidation of reduced humic substances to the reduction of nitrate. No HS oxidation occurred in the absence of cells and in the absence of a suitable electron acceptor, demonstrating that these organisms were capable of utilizing natural HS as an energy source and that AHDS serves as a suitable analog for studying this metabolism. Alternative electron donors included simple volatile fatty acids such as propionate, butyrate, and valerate as well as simple organic acids such as lactate and pyruvate. Analysis of the complete sequences of the 16S rRNA genes revealed that the isolates were not closely related to each other and were phylogenetically diverse, with members in the alpha, beta, gamma, and delta subdivisions of the Proteobacteria. Most of the isolates were closely related to known genera not previously recognized for their ability to couple growth to HS oxidation, while one of the isolates represented a new genus in the delta subclass of the Proteobacteria. The results presented here demonstrate that microbial oxidation of HS is a ubiquitous metabolism in the environment. This study represents the first description of HS-oxidizing isolates and demonstrates that microorganisms capable of HS oxidation are phylogenetically diverse. PMID:11976120

Diversity and ubiquity of bacteria capable of utilizing humic substances as electron donors for anaerobic respiration.

PubMed

Coates, John D; Cole, Kimberly A; Chakraborty, Romy; O'Connor, Susan M; Achenbach, Laurie A

2002-05-01

Previous studies have demonstrated that reduced humic substances (HS) can be reoxidized by anaerobic bacteria such as Geobacter, Geothrix, and Wolinella species with a suitable electron acceptor; however, little is known of the importance of this metabolism in the environment. Recently we investigated this metabolism in a diversity of environments including marine and aquatic sediments, forest soils, and drainage ditch soils. Most-probable-number enumeration studies were performed using 2,6-anthrahydroquinone disulfonate (AHDS), an analog for reduced HS, as the electron donor with nitrate as the electron acceptor. Anaerobic organisms capable of utilizing reduced HS as an electron donor were found in all environments tested and ranged from a low of 2.31 x 10(1) in aquifer sediments to a high of 9.33 x 10(6) in lake sediments. As part of this study we isolated six novel organisms capable of anaerobic AHDS oxidation. All of the isolates coupled the oxidation of AHDS to the reduction of nitrate with acetate (0.1 mM) as the carbon source. In the absence of cells, no AHDS oxidation was apparent, and in the absence of AHDS, no cell density increase was observed. Generally, nitrate was reduced to N(2). Analysis of the AHDS and its oxidized form, 2,6-anthraquinone disulfonate (AQDS), in the medium during growth revealed that the anthraquinone was not being biodegraded as a carbon source and was simply being oxidized as an energy source. Determination of the AHDS oxidized and nitrate reduced accounted for 109% of the theoretical electron transfer. In addition to AHDS, all of these isolates could also couple the oxidation of reduced humic substances to the reduction of nitrate. No HS oxidation occurred in the absence of cells and in the absence of a suitable electron acceptor, demonstrating that these organisms were capable of utilizing natural HS as an energy source and that AHDS serves as a suitable analog for studying this metabolism. Alternative electron donors included simple volatile fatty acids such as propionate, butyrate, and valerate as well as simple organic acids such as lactate and pyruvate. Analysis of the complete sequences of the 16S rRNA genes revealed that the isolates were not closely related to each other and were phylogenetically diverse, with members in the alpha, beta, gamma, and delta subdivisions of the PROTEOBACTERIA: Most of the isolates were closely related to known genera not previously recognized for their ability to couple growth to HS oxidation, while one of the isolates represented a new genus in the delta subclass of the PROTEOBACTERIA: The results presented here demonstrate that microbial oxidation of HS is a ubiquitous metabolism in the environment. This study represents the first description of HS-oxidizing isolates and demonstrates that microorganisms capable of HS oxidation are phylogenetically diverse.

Co-occurrence of anaerobic bacteria in colorectal carcinomas.

PubMed

Warren, René L; Freeman, Douglas J; Pleasance, Stephen; Watson, Peter; Moore, Richard A; Cochrane, Kyla; Allen-Vercoe, Emma; Holt, Robert A

2013-05-15

Numerous cancers have been linked to microorganisms. Given that colorectal cancer is a leading cause of cancer deaths and the colon is continuously exposed to a high diversity of microbes, the relationship between gut mucosal microbiome and colorectal cancer needs to be explored. Metagenomic studies have shown an association between Fusobacterium species and colorectal carcinoma. Here, we have extended these studies with deeper sequencing of a much larger number (n = 130) of colorectal carcinoma and matched normal control tissues. We analyzed these data using co-occurrence networks in order to identify microbe-microbe and host-microbe associations specific to tumors. We confirmed tumor over-representation of Fusobacterium species and observed significant co-occurrence within individual tumors of Fusobacterium, Leptotrichia and Campylobacter species. This polymicrobial signature was associated with over-expression of numerous host genes, including the gene encoding the pro-inflammatory chemokine Interleukin-8. The tumor-associated bacteria we have identified are all Gram-negative anaerobes, recognized previously as constituents of the oral microbiome, which are capable of causing infection. We isolated a novel strain of Campylobacter showae from a colorectal tumor specimen. This strain is substantially diverged from a previously sequenced oral Campylobacter showae isolate, carries potential virulence genes, and aggregates with a previously isolated tumor strain of Fusobacterium nucleatum. A polymicrobial signature of Gram-negative anaerobic bacteria is associated with colorectal carcinoma tissue.

Characterization of arsenic resistant bacteria from arsenic rich groundwater of West Bengal, India.

PubMed

Sarkar, Angana; Kazy, Sufia K; Sar, Pinaki

2013-03-01

Sixty-four arsenic (As) resistant bacteria isolated from an arsenic rich groundwater sample of West Bengal were characterized to investigate their potential role in subsurface arsenic mobilization. Among the isolated strains predominance of genera Agrobacterium/Rhizobium, Ochrobactrum and Achromobacter which could grow chemolitrophically and utilize arsenic as electron donor were detected. Higher tolerance to As(3+) [maximum tolerable concentration (MTC): ≥10 mM], As(5+) (MTC: ≥100 mM) and other heavy metals like Cu(2+), Cr(2+), Ni(2+) etc. (MTC: ≥10 mM), presence of arsenate reductase and siderophore was frequently observed among the isolates. Ability to produce arsenite oxidase and phosphatase enzyme was detected in 50 and 34 % of the isolates, respectively. Although no direct correlation among taxonomic identity of bacterial strains and their metabolic abilities as mentioned above was apparent, several isolates affiliated to genera Ochrobactrum, Achromobacter and unclassified Rhizobiaceae members were found to be highly resistant to As(3+) and As(5+) and positive for all the test properties. Arsenate reductase activity was found to be conferred by arsC gene, which in many strains was coupled with arsenite efflux gene arsB as well. Phylogenetic incongruence between the 16S rRNA and ars genes lineages indicated possible incidence of horizontal gene transfer for ars genes. Based on the results we propose that under the prevailing low nutrient condition inhabitant bacteria capable of using inorganic electron donors play a synergistic role wherein siderophores and phosphatase activities facilitate the release of sediment bound As(5+), which is subsequently reduced by arsenate reductase resulting into the mobilization of As(3+) in groundwater.

[Diversity of oil-degrading bacteria isolated form the Indian Ocean sea surface].

PubMed

Wu, Changliang; Wang, Xin; Shao, Zongze

2010-09-01

In order to investigate the diversity of oil-degrading bacteria in the surface seawater across the India Ocean, and to obtain new oil-degrading bacteria. Potential oil-degrading bacteria were selected out via 1:1 mixture of diesel and crude oil as sole carbon source. Meanwhile, the community structure of 13 enrichments was analyzed by polymerase chain reaction with denaturing gradient gel electrophoresis (PCR-DGGE). We obtained 51 unique strains of 29 genera after screening via morphological, physiological, biochemical and 16S rRNA analyses. They mainly belonged to a and gamma-Proteobacteria. The four genera Alcanivorax (accounting for 18%), Novosphingobium (10%), Marinobacter (6%) and Thalassospira (6%) were the most predominant bacteria. Ecological analyses showed that the bacteria had high diversity with Shannon-Winner index (H) of 4.57968, and distributed even with Evenness index (E) as 0.8664771. Then Further experiments revealed oil-degrading capability of 49 strains. In addition, our investigation revealed oil-degrading ability of genera Sinomonas, Knoellia and Mesoflavibacter for the first time. DGGE fingerprint patterns indicated that the genus Alcanivorax was an important oil-degrading bacteria in the surface seawater across the India Ocean. This study demonstrated a high diversity of the oil-degradation bacteria in the surface seawater of Indian Ocean, these bacteria are of potential in bioremediation of marine oil pollution.

Biodegradation of Mixed PAHs by PAH-Degrading Endophytic Bacteria.

PubMed

Zhu, Xuezhu; Ni, Xue; Waigi, Michael Gatheru; Liu, Juan; Sun, Kai; Gao, Yanzheng

2016-08-09

Endophytic bacteria can promote plant growth, induce plant defence mechanisms, and increase plant resistance to organic contaminants. The aims of the present study were to isolate highly PAH-degrading endophytic bacteria from plants growing at PAH-contaminated sites and to evaluate the capabilities of these bacteria to degrade polycyclic aromatic hydrocarbons (PAHs) in vitro, which will be beneficial for re-colonizing target plants and reducing plant PAH residues through the inoculation of plants with endophytic bacteria. Two endophytic bacterial strains P₁ (Stenotrophomonas sp.) and P₃ (Pseudomonas sp.), which degraded more than 90% of phenanthrene (PHE) within 7 days, were isolated from Conyza canadensis and Trifolium pretense L., respectively. Both strains could use naphthalene (NAP), PHE, fluorene (FLR), pyrene (PYR), and benzo(a)pyrene (B(a)P) as the sole sources of carbon and energy. Moreover, these bacteria reduced the contamination of mixed PAHs at high levels after inoculation for 7 days; strain P₁ degraded 98.0% NAP, 83.1% FLR, 87.8% PHE, 14.4% PYR, and 1.6% B(a)P, and strain P₃ degraded 95.3% NAP, 87.9% FLR, 90.4% PHE, 6.9% PYR, and negligible B(a)P. Notably, the biodegradation of PAHs could be promoted through additional carbon and nitrogen nutrients; therein, beef extract was suggested as the optimal co-substrate for the degradation of PAHs by these two strains (99.1% PHE was degraded within 7 days). Compared with strain P₁, strain P₃ has more potential for the use in the removal of PAHs from plant tissues. These results provide a novel perspective in the reduction of plant PAH residues in PAH-contaminated sites through inoculating plants with highly PAH-degrading endophytic bacteria.

Carbaryl degradation by bacterial isolates from a soil ecosystem of the Gaza Strip

PubMed Central

Hamada, Mazen; Matar, Ammar; Bashir, Abdallah

2015-01-01

Abstract Carbaryl is an important and widely used insecticide that pollutes soil and water systems. Bacteria from the local soil ecosystem of the Gaza Strip capable of utilizing carbaryl as the sole source of carbon and nitrogen were isolated and identified as belonging to Bacillus, Morganella, Pseudomonas, Aeromonas and Corynebacterium genera. Carbaryl biodegradation by Bacillus, Morganella and Corynebacterium isolates was analyzed in minimal liquid media supplemented with carbaryl as the only source of carbon and nitrogen. Bacillus and Morganella exhibited 94.6% and 87.3% carbaryl degradation, respectively, while Corynebacterium showed only moderate carbaryl degradation at 48.8%. These results indicate that bacterial isolates from a local soil ecosystem in the Gaza Strip are able to degrade carbaryl and can be used to decrease the risk of environmental contamination by this insecticide. PMID:26691466

Characterization of boron tolerant bacteria isolated from a fly ash dumping site for bacterial boron remediation.

PubMed

Edward Raja, Chellaiah; Omine, Kiyoshi

2013-08-01

Boron is an essential micronutrient for plants, but can above certain concentrations be toxic to living organisms. A major environmental concern is the removal of boron from contaminated water and fly ash. For this purpose, the samples were collected from a fly ash dumping site, Nagasaki prefecture, Japan. The chemical characteristics and heavy metal concentration of the samples were performed by X-ray fluorescent analysis and leaching test. For bacterial analysis, samples were collected in sterile plastic sheets and isolation was carried out by serial dilution method. The boron tolerant isolates that showed values of maximum inhibitory concentration toward boron ranging from 100 to 260 mM level were screened. Based on 16S rRNA sequencing and phylogenetic analysis, the isolates were most closely related to the genera Bacillus, Lysinibacillus, Microbacterium and Ralstonia. The boron tolerance of these strains was also associated with resistant to several heavy metals, such as As (III), Cr (VI), Cd, Cu, Pb, Ni, Se (III) and Zn. Indeed, these strains were arsenic oxidizing bacteria confirmed by silver nitrate test. These strains exhibited their salt resistances ranging from 4 to 15 % were determined in Trypticase soy agar medium. The boron tolerant strains were capable of removing 0.1-2.0 and 2.7-3.7 mg l(-1) boron from the medium and fly ash at 168 h. Thus, we have successfully identified the boron tolerant and removal bacteria from a fly ash dumping site for boron remediation.

Draft genome sequence of Brevibacterium epidermidis EZ-K02 isolated from nitrocellulose-contaminated wastewater environments.

PubMed

Ziganshina, Elvira E; Mohammed, Waleed S; Doijad, Swapnil P; Shagimardanova, Elena I; Gogoleva, Natalia E; Ziganshin, Ayrat M

2018-04-01

Brevibacterium spp. are aerobic, nonbranched, asporogenous, gram-positive, rod-shaped bacteria which may exhibit a rod-coccus cycle when cells get older and can be found in various environments. ​Several Brevibacterium species have industrial importance and are capable of biotransformation of various contaminants. Here we describe the draft genome sequence of Brevibacterium epidermidis EZ-K02 isolated from nitrocellulose-contaminated wastewater environments. The genome comprises 3,885,924 bp, with a G + C content of 64.2%. This whole genome shotgun project has been deposited at DDBJ/ENA/GenBank under the accession PDHL00000000.

Isolation of Acinetobacter from Soil and Water

PubMed Central

Baumann, Paul

1968-01-01

An enrichment culture procedure for isolating members of the genus Acinetobacter from soil and water is described. It involves the use of vigorously aerated mineral media at relative low pH, supplemented with acetate or other suitable carbon source and nitrate as nitrogen source. With this method, virtually all samples of soil and water yielded representatives of this genus. Semiquantitative comparisons of the numbers of Acinetobacter and of all bacteria capable of aerobic growth in a complex medium revealed that Acinetobacter constituted no less than 0.001% of the total heterotrophic aerobic population in soil and water and was one of the predominant organisms in some water samples. PMID:4874313

Taxonomically-linked growth phenotypes during arsenic stress among arsenic resistant bacteria isolated from soils overlying the Centralia coal seam fire.

PubMed

Dunivin, Taylor K; Miller, Justine; Shade, Ashley

2018-01-01

Arsenic (As), a toxic element, has impacted life since early Earth. Thus, microorganisms have evolved many As resistance and tolerance mechanisms to improve their survival outcomes given As exposure. We isolated As resistant bacteria from Centralia, PA, the site of an underground coal seam fire that has been burning since 1962. From a 57.4°C soil collected from a vent above the fire, we isolated 25 unique aerobic As resistant bacterial strains spanning seven genera. We examined their diversity, resistance gene content, transformation abilities, inhibitory concentrations, and growth phenotypes. Although As concentrations were low at the time of soil collection (2.58 ppm), isolates had high minimum inhibitory concentrations (MICs) of arsenate and arsenite (>300 mM and 20 mM respectively), and most isolates were capable of arsenate reduction. We screened isolates (PCR and sequencing) using 12 published primer sets for six As resistance genes (AsRGs). Genes encoding arsenate reductase (arsC) and arsenite efflux pumps (arsB, ACR3(2)) were present, and phylogenetic incongruence between 16S rRNA genes and AsRGs provided evidence for horizontal gene transfer. A detailed investigation of differences in isolate growth phenotypes across As concentrations (lag time to exponential growth, maximum growth rate, and maximum OD590) showed a relationship with taxonomy, providing information that could help to predict an isolate's performance given As exposure in situ. Our results suggest that microbiological management and remediation of environmental As could be informed by taxonomically-linked As tolerance, potential for resistance gene transferability, and the rare biosphere.

Biofertilization and Biocontrol in the fight against soilborne fungal root pathogens in Australian soils

NASA Astrophysics Data System (ADS)

Cooper, Sarah; Agnew, Linda; Pereg, Lily

2015-04-01

Control of soilborne fungal root pathogens that severely compromise cotton production and other crops worldwide has historically been through the use of synthetic fungicides and fertilizers, these often have hazardous implications for environmental and soil health. The search for sustainable alternatives has lead to heightened interest in biocontrol, using soil microorganisms that suppress the growth of phytopathogens directly and biofertilization, the use of microorganisms to increasing the nutrient availability in soils, increasing seedling vigour. Soil properties and consequently soil microbial properties are strongly impacted by agricultural practices, therefore we are isolating indigenous microorganisms from soils collected from ten different geographical locations within the Australian cotton-growing region. These differ vastly in soil type and management practices. Soils are being analysed to compare the abundance of phosphate solubilising, auxin producing and nitrogen cycling bacteria. Rhizospheric bacteria capable of plant growth promoting through a multiple actions are being isolated. In addition, a method for isolating soilborne fungal suppressive microbes directly from soil samples has been designed and is currently being used. Comparisons between agricultural practices and the plant growth promoting microbial component of soil microbiome will be reported on. We will discuss the microbial isolates identified, their modes of action and their potential use as biocontrol agents and/or biofertilizers in Australian cotton growing soils.

Microbial reductive dehalogenation of vinyl chloride

DOEpatents

Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Nannhein, DE; Meshulam-Simon, Galit [Los Altos, CA; McCarty, Perry L [Stanford, CA

2011-11-22

Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

Microbial reductive dehalogenation of vinyl chloride

DOEpatents

Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Mannheim, DE; Meshulam-Simon, Galit [Los Angeles, CA; McCarty, Perry L [Stanford, CA

2014-02-11

Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

Prevalence and antibiotic-resistance characteristics of Enterococcus spp. Isolated from free-living and captive raptors in Central Illinois.

PubMed

Marrow, Judilee; Whittington, Julia K; Mitchell, Mark; Hoyer, Lois L; Maddox, Carol

2009-04-01

Due to their predatory nature, raptor species may serve as important indicators of environmental contamination with antimicrobial-resistant bacteria. Raptors prey on small rodents and birds that have diverse habitat ranges, including urban and rural environments, and their intestinal microflora can reflect that of the animals on which they feed. Enterococcus spp. were selected as target organisms because they have been isolated from the avian gastrointestinal tract, can be conferred by prey items, and because they are capable of multiple resistance patterns. They are also a concerning source of human antimicrobial resistance. In this study fecal cultures were obtained from 15 May 2004 to 31 August 2004, from 21 free-living raptors and four captive raptors. Enterococcus was isolated from 21 (84%) of the 25 birds, and 54 isolates were chosen for further study based upon unique colony morphology. The most common isolate recovered was Enterococcus faecalis (95%, 95% confidence interval [CI]: 89-100). One bird in the study was determined to have Enterococcus gallinarum. Two distinct ribotypes of E. faecalis were identified, one with unique bands at 11 and 13 kb and the other with unique bands at 14 and 20 kb. Both ribotypes were found in free-living and captive birds. The Enterococcus isolates in this study demonstrated a variety of antimicrobial-resistance characteristics, including almost complete resistance to amikacin, first-generation cephalosporins, spectinomycin, and sulphadimethoxime. Isolates demonstrated variable resistance to chloramphenicol, gentamicin, enrofloxacin, erythromycin, and ticarcillin. No phenotypically vancomycin-resistant E. faecalis isolates were recovered from any of the raptors; three isolates had intermediate level susceptibility. A significantly higher number of isolates collected from captive birds demonstrated resistance to chloramphenicol than those obtained from free-living birds. This trend was not duplicated with any of the remaining 18 antimicrobial drugs tested. The results of this study suggest that raptors in central Illinois are coming into contact with antimicrobials, prey exposed to antimicrobials, or bacteria that are capable of transferring resistance genes. Further study is needed to determine the source of antimicrobial-resistant Enterococcus in free-living raptors but the limited data reflecting few differences between birds with and without antimicrobial exposure suggests that treatment and release of treated wild raptors is not contributing significantly to antimicrobial resistance in the environment.

Phylogenetic characterization of a corrosive consortium isolated from a sour gas pipeline.

PubMed

Jan-Roblero, J; Romero, J M; Amaya, M; Le Borgne, S

2004-06-01

Biocorrosion is a common problem in oil and gas industry facilities. Characterization of the microbial populations responsible for biocorrosion and the interactions between different microorganisms with metallic surfaces is required in order to implement efficient monitoring and control strategies. Denaturing gradient gel electrophoresis (DGGE) analysis was used to separate PCR products and sequence analysis revealed the bacterial composition of a consortium obtained from a sour gas pipeline in the Gulf of Mexico. Only one species of sulfate-reducing bacteria (SRB) was detected in this consortium. The rest of the population consisted of enteric bacteria with different characteristics and metabolic capabilities potentially related to biocorrosion. Therefore, several types of bacteria may be involved in biocorrosion arising from natural biofilms that develop in industrial facilities. The low abundance of the detected SRB was evidenced by environmental scanning electron microscopy (ESEM). In addition, the localized corrosion of pipeline steel in the presence of the consortium was clearly observed by ESEM after removing the adhered bacteria.

Antagonistic activity of isolated lactic acid bacteria from Pliek U against gram-negative bacteria Escherichia coli ATCC 25922

NASA Astrophysics Data System (ADS)

Kiti, A. A.; Jamilah, I.; Rusmarilin, H.

2017-09-01

Lactic acid bacteria (LAB) is one group of microbes that has many benefits, notably in food and health industries sector. LAB plays an important role in food fermentation and it has bacteriostatic effect against the growth of pathogenic microorganisms. The research related LAB continued to be done to increase the diversity of potential isolates derived from nature which is indigenous bacteria for biotechnological purposes. This study was aimed to isolate and characterize LAB derived from pliek u sample and to examine the potency to inhibits Escherichia coli ATCC 25922 bacteria growth. A total of 5 isolates were isolated and based on morphological and physiological characteristics of the fifth bacteria, they are allegedly belonging to the genus Bacillus. Result of antagonistic test showed that the five isolates could inhibits the growth of E. coli ATCC 25922. The highest inhibition zone is 8.5 mm was shown by isolates NQ2, while the lowest inhibition is 1.5 mm was shown by isolates NQ3.

Preliminary survey of antibiotic-resistant fecal indicator bacteria and pathogenic Escherichia coli from river-water samples collected in Oakland County, Michigan, 2003

USGS Publications Warehouse

Fogarty, Lisa R.; Duris, Joseph W.; Aichele, Stephen S.

2005-01-01

A preliminary study was done in Oakland County, Michigan, to determine the concentration of fecal indicator bacteria (fecal coliform bacteria and enterococci), antibiotic resistance patterns of these two groups, and the presence of potentially pathogenic Escherichia coli (E. coli). For selected sites, specific members of these groups [E. coli, Enterococcus faecium (E. faecium) and Enterococcus faecalis (E. faecalis)] were isolated and tested for levels of resistance to specific antibiotics used to treat human infections by pathogens in these groups and for their potential to transfer these resistances. In addition, water samples from all sites were tested for indicators of potentially pathogenic E. coli by three assays: a growth-based assay for sorbitol-negative E. coli, an immunological assay for E. coli O157, and a molecular assay for three virulence and two serotype genes. Samples were also collected from two non-urbanized sites outside of Oakland County. Results from the urbanized Oakland County area were compared to those from these two non-urbanized sites. Fecal indicator bacteria concentrations exceeded State of Michigan recreational water-quality standards and (or) recommended U.S. Environmental Protection Agency (USEPA) standards in samples from all but two Oakland County sites. Multiple-antibiotic-resistant fecal coliform bacteria were found at all sites, including two reference sites from outside the county. Two sites (Stony Creek and Paint Creek) yielded fecal coliform isolates resistant to all tested antibiotics. Patterns indicative of extended-spectrum-β-lactamase (ESBL)- producing fecal coliform bacteria were found at eight sites in Oakland County and E. coli resistant to clinically significant antibiotics were recovered from the River Rouge, Clinton River, and Paint Creek. Vancomycin-resistant presumptive enterococci were found at six sites in Oakland County and were not found at the reference sites. Evidence of acquired antibiotic resistances was detected in bacteria from multiple sites in Oakland County but not detected in bacteria from the reference sites. Integrons capable of transferring resistance were detected in isolates from the River Rouge and Clinton River. E. faecium and E. faecalis identified in samples collected from Kearsley Creek and Evans Ditch were resistant to high levels of vancomycin and carried transferable genes responsible for resistance. Several sites in Oakland County had indicators of pathogenic E. coli in August and (or) September 2003. Two samples from the Clinton River in August tested positive for all three E. coli O157 tests. Both the August and September samples from one River Rouge site were positive for the immunological and molecular assay for E. coli O157. A combination of virulence genes commonly associated with human illness was detected at five sites in August and seven sites in September. Antibiotic-resistance profiles of clinical concern along with genes capable of transferring the resistance were found at several sites throughout Oakland County; samples from many of these sites also contained potentially pathogenic E. coli.

Isolation and characterization of a novel chlorpyrifos degrading flavobacterium species EMBS0145 by 16S rRNA gene sequencing.

PubMed

Amareshwari, P; Bhatia, Mayuri; Venkatesh, K; Roja Rani, A; Ravi, G V; Bhakt, Priyanka; Bandaru, Srinivas; Yadav, Mukesh; Nayarisseri, Anuraj; Nair, Achuthsankar S

2015-03-01

Indiscriminate application of pesticides like chlorpyrifos, diazinon, or malathion contaminate the soil in addition has being unsafe often it has raised severe health concerns. Conversely, microorganisms like Trichoderma, Aspergillus and Bacteria like Rhizobium Bacillus, Azotobacter, Flavobacterium etc have evolved that are endowed with degradation of pesticides aforementioned to non-toxic products. The current study pitches into identification of a novel species of Flavobacterium bacteria capable to degrade the Organophosphorous pesticides. The bacterium was isolated from agricultural soil collected from Guntur District, Andhra Pradesh, India. The samples were serially diluted and the aliquots were incubated for a suitable time following which the suspected colony was subjected to 16S rDNA sequencing. The sequence thus obtained was aligned pairwise against Flavobacterium species, which resulted in identification of novel specie of Flavobacterium later named as EMBS0145, the sequence of which was deposited in in GenBank with accession number JN794045.

Isolation of a halophilic bacterium, Bacillus sp. strain NY-6 for organic contaminants removal in saline wastewater on ship

NASA Astrophysics Data System (ADS)

Gao, Jie; Yu, Zhenjiang; Zhang, Xiaohui; Zhao, Dan; Zhao, Fangbo

2013-06-01

The objective of this research was to examine if certain strains of Bacillus bacteria, could survive in dry powder products and if so, could the bacteria degrade organic contaminants in saline wastewater on a ship. As part of the study, we isolated 7 domesticated strains named NY1, NY2,..., and NY7, the strain NY6 showed to have the best performance for organic matter degradation and could survive in dry powder more than 3 months. NY6 was identified as Bacillus aerius, based on the morphological and physic-chemical properties. Its optimal growth conditions were as follows: salinity was 2%; temperature was 37°C; pH was in 6.5-7.0; best ratio of C: N: P was 100:5:1. The capability of its dry powder for Chemical Oxygen Demand (COD) removal was 800mg COD/g in synthesized marine wastewater with 2% salinity. The spores in the dry powder were 1.972×108 g -1.

Calcite-forming bacteria for compressive strength improvement in mortar.

PubMed

Park, Sung-Jin; Park, Yu-Mi; Chun, Woo-Young; Kim, Wha-Jung; Ghim, Sa-Youl

2010-04-01

Microbiological calcium carbonate precipitation (MCP) has been investigated for its ability to improve the compressive strength of concrete mortar. However, very few studies have been conducted on the use of calcite-forming bacteria (CFB) to improve compressive strength. In this study, we discovered new bacterial genera that are capable of improving the compressive strength of concrete mortar. We isolated 4 CFB from 7 environmental concrete structures. Using sequence analysis of the 16S rRNA genes, the CFB could be partially identified as Sporosarcina soli KNUC401, Bacillus massiliensis KNUC402, Arthrobacter crystallopoietes KNUC403, and Lysinibacillus fusiformis KNUC404. Crystal aggregates were apparent in the bacterial colonies grown on an agar medium. Stereomicroscopy, scanning electron microscopy, and x-ray diffraction analyses illustrated both the crystal growth and the crystalline structure of the CaCO3 crystals. We used the isolates to improve the compressive strength of concrete mortar cubes and found that KNUC403 offered the best improvement in compressive strength.

Effect of media composition, including gelling agents, on isolation of previously uncultured rumen bacteria.

PubMed

Nyonyo, T; Shinkai, T; Tajima, A; Mitsumori, M

2013-01-01

The aim of this study was to develop novel anaerobic media using gellan gum for the isolation of previously uncultured rumen bacteria. Four anaerobic media, a basal liquid medium (BM) with agar (A-BM), a modified BM (MBM) with agar (A-MBM), an MBM with phytagel (P-MBM) and an MBM with gelrite (G-MBM) were used for the isolation of rumen bacteria and evaluated for the growth of previously uncultured rumen bacteria. Of the 214 isolates composed of 144 OTUs, 103 isolates (83 OTUs) were previously uncultured rumen bacteria. Most of the previously uncultured strains were obtained from A-MBM, G-MBM and P-MBM, but the predominant cultural members, isolated from each medium, differed. A-MBM and G-MBM showed significantly higher numbers of different OTUs derived from isolates than A-BM (P < 0·05). The Shannon index indicated that the isolates of A-MBM showed the highest diversity (H' = 3·89) compared with those of G-MBM, P-MBM and A-BM (H' = 3·59, 3·23 and 3·39, respectively). Although previously uncultured rumen bacteria were isolated from all media used, the ratio of previously uncultured bacteria to total isolates was increased in A-MBM, P-MBM and G-MBM. © 2012 The Society for Applied Microbiology.

Immobilization of iron- and manganese-oxidizing bacteria with a biofilm-forming bacterium for the effective removal of iron and manganese from groundwater.

PubMed

Li, Chunyan; Wang, Shuting; Du, Xiaopeng; Cheng, Xiaosong; Fu, Meng; Hou, Ning; Li, Dapeng

2016-11-01

In this study, three bacteria with high Fe- and Mn-oxidizing capabilities were isolated from groundwater well sludge and identified as Acinetobacter sp., Bacillus megaterium and Sphingobacterium sp. The maximum removal ratios of Fe and Mn (99.75% and 96.69%) were obtained by an optimal combination of the bacteria at a temperature of 20.15°C, pH 7.09 and an inoculum size of 2.08%. Four lab-scale biofilters were tested in parallel for the removal of iron and manganese ions from groundwater. The results indicated that the Fe/Mn removal ratios of biofilter R4, which was inoculated with iron- and manganese-oxidizing bacteria and a biofilm-forming bacterium, were approximately 95% for each metal during continuous operation and were better than the other biofilters. This study demonstrated that the biofilm-forming bacterium could promote the immobilization of the iron- and manganese-oxidizing bacteria on the biofilters and enhance the removal efficiency of iron and manganese ions from groundwater. Copyright © 2016 Elsevier Ltd. All rights reserved.

A New Catabolic Plasmid in Xanthobacter and Starkeya spp. from a 1,2-Dichloroethane-Contaminated Site

PubMed Central

Munro, Jacob E.; Liew, Elissa F.; Ly, Mai-Anh

2016-01-01

ABSTRACT 1,2-Dichloroethane (DCA) is a problematic xenobiotic groundwater pollutant. Bacteria are capable of biodegrading DCA, but the evolution of such bacteria is not well understood. In particular, the mechanisms by which bacteria acquire the key dehalogenase genes dhlA and dhlB have not been well defined. In this study, the genomic context of dhlA and dhlB was determined in three aerobic DCA-degrading bacteria (Starkeya novella strain EL1, Xanthobacter autotrophicus strain EL4, and Xanthobacter flavus strain EL8) isolated from a groundwater treatment plant (GTP). A haloalkane dehalogenase gene (dhlA) identical to the canonical dhlA gene from Xanthobacter sp. strain GJ10 was present in all three isolates, and, in each case, the dhlA gene was carried on a variant of a 37-kb circular plasmid, which was named pDCA. Sequence analysis of the repA replication initiator gene indicated that pDCA was a member of the pTAR plasmid family, related to catabolic plasmids from the Alphaproteobacteria, which enable growth on aromatics, dimethylformamide, and tartrate. Genes for plasmid replication, mobilization, and stabilization were identified, along with two insertion sequences (ISXa1 and ISPme1) which were likely to have mobilized dhlA and dhlB and played a role in the evolution of aerobic DCA-degrading bacteria. Two haloacid dehalogenase genes (dhlB1 and dhlB2) were detected in the GTP isolates; dhlB1 was most likely chromosomal and was similar to the canonical dhlB gene from strain GJ10, while dhlB2 was carried on pDCA and was not closely related to dhlB1. Heterologous expression of the DhlB2 protein confirmed that this plasmid-borne dehalogenase was capable of chloroacetate dechlorination. IMPORTANCE Earlier studies on the DCA-degrading Xanthobacter sp. strain GJ10 indicated that the key dehalogenases dhlA and dhlB were carried on a 225-kb linear plasmid and on the chromosome, respectively. The present study has found a dramatically different gene organization in more recently isolated DCA-degrading Xanthobacter strains from Australia, in which a relatively small circular plasmid (pDCA) carries both dhlA and dhlB homologs. pDCA represents a true organochlorine-catabolic plasmid, first because its only obvious metabolic phenotype is dehalogenation of organochlorines, and second because acquisition of this plasmid provides both key enzymes required for carbon-chlorine bond cleavage. The discovery of the alternative haloacid dehalogenase dhlB2 in pDCA increases the known genetic diversity of bacterial chloroacetate-hydrolyzing enzymes. PMID:27342553

Antibiotic resistance and biofilm formation of some bacteria isolated from sediment, water and fish farms in Malaysia

NASA Astrophysics Data System (ADS)

Faja, Orooba Meteab; Usup, Gires; Ahmad, Asmat

2018-04-01

A total of 90 isolates of bacteria were isolated, from sediment (10) samples, water (10) samples and fish (12) samples (Sea bass, Snapper, Grouper and Tilapia). These include 22 isolates of bacteria from sediment, 28 isolates from water and 40 isolates from fish. All the isolates were tested for sensitivity to 13 antibiotics using disc diffusion method. The isolates showed high resistance to some antibiotics based on samples source. Isolates from sediment showed highest resistance toward novobiocin, kanamycin, ampicillin and streptomycin while isolates from water showed highest resistance against vancomycin, penicillin, streptomycin and tetracycline, in contrast, in fish sample showed highest resistance toward vancomycin, ampicillin, streptomycin and tetracycline. Most of the isolates showed biofilm formation ability with different degrees. Out of 22 bacteria isolates from water, two isolates were weak biofilm formers, six isolates moderate biofilm formers and fourteen isolates strong biofilm formers. While, out of 28 bacteria isolates from water one isolate was weak biofilm former, five isolates moderate biofilm formers and 22 strong biofilm formers Fish isolate showed three isolates (8%) moderate biofilm formers and 27 isolates strong biofilm formers. Biofilm formation was one of the factors that lead to antibiotic resistance of the bacterial isolates from these samples.

Characterization of Exoelectrogenic Bacteria Enterobacter Strains Isolated from a Microbial Fuel Cell Exposed to Copper Shock Load

PubMed Central

Feng, Cuijie; Li, Jiangwei; Qin, Dan; Chen, Lixiang; Zhao, Feng; Chen, Shaohua; Hu, Hongbo; Yu, Chang-Ping

2014-01-01

Microorganisms capable of generating electricity in microbial fuel cells (MFCs) have gained increasing interest. Here fourteen exoelectrogenic bacterial strains were isolated from the anodic biofilm in an MFC before and after copper (Cu) shock load by Hungate roll-tube technique with solid ferric (III) oxide as an electron acceptor and acetate as an electron donor. Phylogenetic analysis of the 16S rRNA gene sequences revealed that they were all closely related to Enterobacter ludwigii DSM 16688T within the Enterobacteriaceae family, although these isolated bacteria showed slightly different morphology before and after Cu shock load. Two representative strains R2B1 (before Cu shock load) and B4B2 (after Cu shock load) were chosen for further analysis. B4B2 is resistant to 200 mg L−1 of Cu(II) while R2B1 is not, which indicated the potential selection of the Cu shock load. Raman analysis revealed that both R2B1 and B4B2 contained c-type cytochromes. Cyclic voltammetry measurements revealed that strain R2B1 had the capacity to transfer electrons to electrodes. The experimental results demonstrated that strain R2B1 was capable of utilizing a wide range of substrates, including Luria-Bertani (LB) broth, cellulose, acetate, citrate, glucose, sucrose, glycerol and lactose to generate electricity, with the highest current density of 440 mA·m−2 generated from LB-fed MFC. Further experiments indicated that the bacterial cell density had potential correlation with the current density. PMID:25412475

Method of separating bacteria from free living amoebae

DOEpatents

Tyndall, Richard L.

1994-01-01

New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

Method of dispersing a hydrocarbon using bacteria

DOEpatents

Tyndall, Richard L.

1996-01-01

New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

Presence of Thermophilic Bacteria in Laundry and Domestic Hot-Water Heaters

PubMed Central

Brock, Thomas D.; Boylen, Kathryn L.

1973-01-01

Thermophilic bacteria resembling Thermus aquaticus were isolated from hot water taken from domestic and commercial hot-water tanks. Cold water from the same locations never yielded thermophilic bacteria, suggesting that the bacteria were growing in the tanks. In contrast to the T. aquaticus isolates from hot springs, the present isolates were rarely pigmented. In general, the hotter sources more frequently yielded bacteria. PMID:4568892

Phenotypic and molecular detection of the bla KPC gene in clinical isolates from inpatients at hospitals in São Luis, MA, Brazil.

PubMed

Ribeiro, Patricia Cristina Saldanha; Monteiro, Andrea Souza; Marques, Sirlei Garcia; Monteiro, Sílvio Gomes; Monteiro-Neto, Valério; Coqueiro, Martina Márcia Melo; Marques, Ana Cláudia Garcia; de Jesus Gomes Turri, Rosimary; Santos, Simone Gonçalves; Bomfim, Maria Rosa Quaresma

2016-12-07

Bacteria that produce Klebsiella pneumoniae carbapenemases (KPCs) are resistant to broad-spectrum β-lactam antibiotics. The objective of this study was to phenotypically and genotypically characterize the antibiotic susceptibility to carbapenems of 297 isolates recovered from clinical samples obtained from inpatients at 16 hospitals in São Luis (Maranhão, Brazil). The study was conducted using phenotypic tests and molecular methods, including polymerase chain reaction (PCR), sequencing and enterobacterial repetitive intergenic consensus (ERIC)-PCR. The nonparametric chi-square test of independence was used to evaluate the associations between the bacterial bla KPC gene and the modified Hodge test, and the chi-square adherence test was used to assess the frequency of carbapenemases and their association with the bla KPC gene. The most frequently isolated species were Acinetobacter baumannii (n = 128; 43.0%), K. pneumoniae (n = 75; 25.2%), and Pseudomonas aeruginosa (n = 42; 14.1%). Susceptibility assays showed that polymixin B was active against 89.3% of the bacterial isolates. The Acinetobacter spp. and K. pneumoniae strains were susceptible to amikacin and tigecycline, and Pseudomonas spp. were sensitive to gentamicin and amikacin. Among the 297 isolates, 100 (33.7%) were positive for the bla KPC gene, including non-fermentative bacteria (A. baumannii) and Enterobacteriaceae species. Among the isolates positive for the bla KPC gene, K. pneumoniae isolates had the highest positivity rate of 60.0%. The bla KPC gene variants detected included KPC-2, which was found in all isolates belonging to species of the Enterobacteriaceae family. KPC-2 and KPC-3 were observed in A. baumannii isolates. Importantly, the bla KPC gene was also detected in three Raoultella isolates and one isolate of the Pantoea genus. ERIC-PCR patterns showed a high level of genetic diversity among the bacterial isolates; it was capable of distinguishing 34 clones among 100 strains that were positive for bla KPC and were circulating in 11 of the surveyed hospitals. The high frequency of the bla KPC gene and the high degree of clonal diversity among microorganisms isolated from patients from different hospitals in São Luis suggest the need to improve the quality of health care to reduce the incidence of infections and the emergence of carbapenem resistance in these bacteria as well as other Gram-negative pathogens.

Isolation of lactic acid bacteria with potential protective culture characteristics from fruits

NASA Astrophysics Data System (ADS)

Hashim, Nurul Huda; Sani, Norrakiah Abdullah

2015-09-01

Lactic acid bacteria are also known as beneficial microorganisms abundantly found in fermented food products. In this study, lactic acid bacteria were isolated from fresh cut fruits obtained from local markets. Throughout the isolation process from 11 samples of fruits, 225 presumptive lactic acid bacteria were isolated on MRS agar medium. After catalase and oxidase tests, 149 resulted to fit the characteristics of lactic acid bacteria. Further identification using Gram staining was conducted to identify the Gram positive bacteria. After this confirmation, the fermentation characteristics of these isolates were identified. It was found that 87 (58.4%) isolates were heterofermentative, while the rest of 62 (41.6%) are homofermentative lactic acid bacteria. Later, all these isolates were investigated for the ability to inhibit growth of Staphylococcus aureus using agar spot assay method. Seven (4.7%) isolates showed strong antagonistic capacity, while 127 (85.2%) and 8 (5.4%) isolates have medium and weak antagonistic capacity, respectively. The other 7 (4.7%) isolates indicated to have no antagonistic effect on S. aureus. Results support the potential of LAB isolated in this study which showed strong antagonistic activity against S. aureus may be manipulated to become protective cultures in food products. While the homofermentative or heterofermentative LAB can be utilized in fermentation of food and non-food products depending on the by-products required during the fermentation.

Exploring Anopheles gut bacteria for Plasmodium blocking activity

PubMed Central

Bahia, Ana C; Dong, Yuemei; Blumberg, Benjamin J; Mlambo, Godfree; Tripathi, Abhai; BenMarzouk-Hidalgo, Omar J; Chandra, Ramesh; Dimopoulos, George

2014-01-01

SUMMARY Malaria parasite transmission requires the successful development of Plasmodium gametocytes into flagellated microgametes upon mosquito blood ingestion, and the subsequent fertilization of microgametes and macrogametes for the development of motile zygotes, called ookinetes, which invade and transverse the Anopheles vector mosquito midgut at around 18-36 h after blood ingestion. Within the mosquito midgut, the malaria parasite has to withstand the mosquito's innate immune response and the detrimental effect of its commensal bacterial flora. We have assessed the midgut colonization capacity of 5 gut bacterial isolates from field-derived, and 2 from laboratory colony, mosquitoes and their effect on Plasmodium development in vivo and in vitro, along with their impact on mosquito survival. Some bacterial isolates activated the mosquito's immune system, affected the mosquito's life span, and were capable of blocking Plasmodium development. We have also shown that the ability of these bacteria to inhibit the parasites is likely to involve different mechanisms and factors. A Serratia marcescens isolate was particularly efficient in colonizing the mosquitoes’ gut, compromising mosquito survival, and inhibiting both sexual- and asexual-stage Plasmodium through secreted factors, thereby rendering it a potential candidate for the development of a malaria transmission intervention strategy. PMID:24428613

In vitro antimicrobial activities of metabolites from vaginal Lactobacillus strains against Clostridium perfringens isolated from a woman's vagina.

PubMed

Amin, Mansour; Moradi Choghakabodi, Parastoo; Alhassan Hamidi, Mohammad; Najafian, Mahin; Farajzadeh Sheikh, Ahmad

2017-01-01

More than 50 different species of bacteria may live in a woman's vagina, with lactobacilli being the predominant microorganism found in healthy adult females. Lactobacilli are relevant as a barrier to infection and are important in the impairment of colonization by pathogens, owing to competitive adherence to adhesion sites in the vaginal epithelium and their capacity to produce antimicrobial compounds. The aim of the present study was to demonstrate the inhibitory capability of Lactobacillus metabolites against Clostridium perfringens, an anaerobic Gram-positive bacterium. These bacteria were isolated from vaginal swabs by using culture-dependent approaches, and the bacteriostatic effect of Lactobacillus metabolites, extracted from different isolates, was assessed using a modified E test. Among the 100 vaginal swabs, 59 (59%) samples showed the presence of Lactobacillus strains and only one sample contained C. perfringens. Lactobacillus metabolites demonstrated the significant potency of in vitro activity against C. perfringens, with minimal inhibitory concentration values ranging from 15.6 μg/mL to 31.2 μg/mL. This study suggests that women without vaginal Lactobacillus strains may be susceptible to nonindigenous and potentially harmful microorganisms. Copyright © 2016. Published by Elsevier Taiwan LLC.

Characterization of newly isolated Lactobacillus delbrueckii-like strain MF-07 isolated from chicken and its role in isoflavone biotransformation.

PubMed

Iqbal, Muhammad Farooq; Zhu, Wei-Yun

2009-02-01

Cecal microbiota of chicken was screened for bacteria involved in the biotransformation of isoflavones. A new facultative anaerobic bacterium, capable of deglycosylation of the isoflavone genistin, was isolated and identified as a Lactobacillus delbrueckii-like strain. The isolate MF-07 was Gram-positive, facultatively anaerobic, catalase negative, non-spore-forming, nonmotile and a straight rod. The polyphasic taxonomic data, along with 16S rRNA gene sequence comparison, demonstrated that the isolate MF-07 was most closely related to L. delbrueckii group of the Lactobacillus genus. Considerable amounts of genistein were accumulated with genistin as a substrate within the first 12 h of fermentation. Formononetin and daidzein were not metabolized. The influence of several carbon sources on the growth of the isolate MF-07 and biotransformation of genistin was also investigated. This is the first study in which an anaerobic Lactobacillus bacterium from the chicken intestinal tract that metabolizes genistin to produce its bioactive metabolite was identified and characterized.

Isolation and identification of bacterial pathogen from mastitis milk in Central Java Indonesia

NASA Astrophysics Data System (ADS)

Harjanti, D. W.; Ciptaningtyas, R.; Wahyono, F.; Setiatin, ET

2018-01-01

Mastitis is a multi-etiologic disease of the mammary gland characterized mainly by reduction in milk production and milk quality due to intramammary infection by pathogenic bacteria. Nearly 83% of lactating dairy cows in Indonesia are infected with mastitis in various inflammation degrees. This study was conducted to isolate and identify the pathogen in milk collected from mastitis-infected dairy cows. The study was carried out in ten smallholder dairy farms in Central Java Indonesia based on animal examination, California mastitis test, isolation bacterial pathogens, Gram staining, Catalase and Coagulase test, and identification of bacteria species using Vitek. Bacteriological examination of milk samples revealed 15 isolates where Streptococcus was predominant species (73.3%) and the coagulase negative Staphylococcus species was identified at the least bacteria (26.7%). The Streptococcus bacteria found were Streptococcus uberis (2 isolates), Streptococcus sanguinis(6 isolates), Streptococcus dysgalactiaessp dysgalactiae(1 isolate) , Streptococcus mitis (1 isolate) and Streptococcus agalactiae (1 isolate). The Staphylococcus isolates comprising of Staphylococcus simulans (1 isolate) and Staphylococcus chromogens (3 isolates). Contamination of raw milkwith pathogenic bacteria can cause outbreaks of human disease (milk borne disease). Thus, proper milk processing method that couldinhibit the growth or kill these pathogenic bacteria is important to ensure the safety of milk and milk products.

Characterization of lactic acid bacteria from local cow´s milk kefir

NASA Astrophysics Data System (ADS)

Ismail, YS; Yulvizar, C.; Mazhitov, B.

2018-03-01

One of products from milk fermentation is kefir. It is made by adding kefir grains which are composed of lactic acid bacteria and yeast into milk. The lactic acid bacteria are a group of bacteria that produce antimicrobial substances and able to inhibit the growth of pathogenic bacteria. In this research, the lactic acid bacteria were isolated from Aceh local cow`s milk kefir to determine the genus of the isolates. The methods used in the characterization of lactic acid bacteria are colony morphology, cell morphology, and biochemical tests which includes a catalase test; 5%, 6.5%, and 10% salt endurance tests; 37°C and 14°C temperature endurance tests, SIM test, TSIA test, MR-VP test, and O/F test. Of the four isolates found from the cow’s milk kefir, two isolates were confirmed as lactic acid bacteria (isolates SK-1 and SK-4). Both isolates are Gram positive bacteria, and have negative catalase activity. From the observations of colony morphology, cell morphology, and biochemical tests, it was found that the genus of SK-1 is Lactobacillus and the genus of SK-4 is Enterococcus.

The structure and functions of bacterial communities in an agrocenosis

NASA Astrophysics Data System (ADS)

Dobrovol'skaya, T. G.; Khusnetdinova, K. A.; Manucharova, N. A.; Balabko, P. N.

2016-01-01

The most significant factor responsible for the specific taxonomic composition of the bacterial communities in the agrocenosis studied was found to be a part or organ of plants (leaves, flowers, roots, fruits). A stage of plant ontogeny also determines changes of taxa. In the course of the plant growth, eccrisotrophic bacteria are replaced by hydrolytic ones that belong to the group of cellulose-decomposing bacteria. Representatives of the proteobacteria genera that are difficult to identify by phenotypic methods were determined using molecular-biological methods. They were revealed only on oat leaves in the moist period. As the vetch-oat mixture was fertilized with BIOUD-1 (foliar application) in the phyllosphere of both oats and vetch, on all the plant organs, representatives of the Rhodococcus genus as dominants were isolated. This fact was related to the capability of bacteria to decompose the complex aromatic compounds that are ingredients of the fertilizers applied. Another positive effect for plants of the bacterial communities forming in agrocenoses is the presence of bacteria that are antagonists of phytopathogenic bacteria. Thus, in agrocenoses, some interrelationships promoting the growth and reproduction of plants are formed in crop plants and bacteria.

DETECTION OF AEROSOLIZED BACTERIA IN EXPIRED AIR SAMPLES FROM ASIAN ELEPHANTS (ELEPHAS MAXIMUS).

PubMed

Burke, Sophie M; Vogelnest, Larry; Thompson, Paul; Tovey, Euan R; Williamson, Peter

2017-06-01

Elephant-mediated transmission of tuberculosis is assumed to be similar to human models, which state close and prolonged contact with an infected individual is required for transmission. Although considered a risk factor for infection, several case studies have reported that close contact with an elephant is not always necessary for transmission, and the role of aerosolized bacteria remains unclear. To investigate aerosol-mediated transmission of pathogenic bacteria from elephants, a method for the detection of aerosols using an adapted sampling system was developed. A commensal bacterium was isolated from the upper respiratory tract of elephants ( Elephas maximus ) and was used as a proxy organism to detect aerosolized droplets in the sampling system. It was found that elephants are capable of producing aerosolized bacterial particles of a size small enough to remain airborne for prolonged periods and penetrate the lower regions of the human respiratory tract.

Bacterial species involved in the conversion of dietary flavonoids in the human gut.

PubMed

Braune, Annett; Blaut, Michael

2016-05-03

The gut microbiota plays a crucial role in the conversion of dietary flavonoids and thereby affects their health-promoting effects in the human host. The identification of the bacteria involved in intestinal flavonoid conversion has gained increasing interest. This review summarizes available information on the so far identified human intestinal flavonoid-converting bacterial species and strains as well as their enzymes catalyzing the underlying reactions. The majority of described species involved in flavonoid transformation are capable of carrying out the O-deglycosylation of flavonoids. Other bacteria cleave the less common flavonoid-C-glucosides and/or further degrade the aglycones of flavonols, flavanonols, flavones, flavanones, dihydrochalcones, isoflavones and monomeric flavan-3-ols. To increase the currently limited knowledge in this field, identification of flavonoid-converting bacteria should be continued using culture-dependent screening or isolation procedures and molecular approaches based on sequence information of the involved enzymes.

Pink-pigmented non-fermentative gram-negative rods associated with human infections: a clinical and diagnostic challenge.

PubMed

Hogue, R; Graves, M; Moler, S; Janda, J M

2007-06-01

Over the past several decades, the appearance of pink-pigmented bacteria in clinical specimens has gone from being a microbiologic curiosity in the clinical laboratory to the recognition of these aerobic microorganisms as etiologic agents of human disease, most notably bloodstream infections. Advances in the fields of molecular taxonomy and phylogenetics indicate that at least four distinct genera and eight different species are associated with clinical infections in susceptible patient populations. However, these bacteria are slow growing and present multiple diagnostic challenges to the microbiology laboratory including culture, isolation, and identification to species rank. This article provides a current review of these unusual non-fermentative chromogenic bacteria including their disease spectrum, taxonomy, and laboratory identification. The review also highlights the pitfalls or shortcomings we currently have in our knowledge of these microbes and their disease-producing capabilities.

Microbial Transformations of Selenium

PubMed Central

Doran, J. W.; Alexander, M.

1977-01-01

Resting cell suspensions of a strain of Corynebacterium isolated from soil formed dimethyl selenide from selenate, selenite, elemental selenium, selenomethionine, selenocystine, and methaneseleninate. Extracts of the bacterium catalyzed the production of dimethyl selenide from selenite, elemental selenium, and methaneseleninate, and methylation of the inorganic Se compounds was enhanced by S-adenosylmethionine. Neither trimethylselenonium nor methaneselenonate was metabolized by the Corynebacterium. Resting cell suspensions of a methionine-utilizing pseudomonad converted selenomethionine to dimethyl diselenide. Six of 10 microorganisms able to grow on cystine used selenocystine as a sole source of carbon and formed elemental selenium, and one of the isolates, a pseudomonad, was found also to produce selenide. Soil enrichments converted trimethylselenonium to dimethyl selenide. Bacteria capable of utilizing trimethylselenonium, dimethyl selenide, and dimethyl diselenide as carbon sources were isolated from soil. PMID:16345188

Mycobacterium fortuitum Cruz from the tropical fish Hyphessobrycon innesi

USGS Publications Warehouse

Ross, A.J.; Brancato, F.P.

1959-01-01

Mycobacterium fortuitum, a rapid-growing, acid-fast bacillus, isolated from a cold abscess of human origin was described by Cruz (1938). Gordon and Smith (1955), in a taxonomic study embracing a group of acid-fast bacteria capable of relatively rapid growth on ordinary media, classified a number of cultures in their collection as M. fortuitum Cruz. In this group were strains isolated from human beings, cattle, soil, and cold-blooded animals including marine fishes. The present study was undertaken to determine the identity of a rapid-growing, acid-fast bacillus isolated at the New York Aquarium from lesions present in a population of freshwater tropical fishes commonly known as the Neon Tetra (Hyphessobrycon innesi). The symptomatology and pathology of this disease have been described by Nigrelli (1953).

In vitro antagonistic activity, plant growth promoting traits and phylogenetic affiliation of rhizobacteria associated with wild plants grown in arid soil.

PubMed

El-Sayed, Wael S; Akhkha, Abdellah; El-Naggar, Moustafa Y; Elbadry, Medhat

2014-01-01

The role of plant growth-promoting rhizobacteria (PGPR) in adaptation of plants in extreme environments is not yet completely understood. For this study native bacteria were isolated from rhizospeheric arid soils and evaluated for both growth-promoting abilities and antagonistic potential against phytopathogenic fungi and nematodes. The phylogentic affiliation of these representative isolates was also characterized. Rhizobacteria associated with 11 wild plant species from the arid soil of Almadinah Almunawarah, Kingdom of Saudi Arabia (KSA) were investigated. From a total of 531 isolates, only 66 bacterial isolates were selected based on their ability to inhibit Fusarium oxysporum, and Sclerotinia sclerotiorum. The selected isolates were screened in vitro for activities related to plant nutrition and plant growth regulation as well as for antifungal and nematicidal traits. Isolated bacteria were found to exhibit capabilities in fix atmospheric nitrogen, produce ammonia, indoleacetic acid (IAA), siderophores, solubilize phosphate and zinc, and showed an antagonistic potential against some phytopathogenic fungi and one nematode species (Meloidogyne incognita) to various extent. Isolates were ranked by their potential ability to function as PGPR. The 66 isolates were genotyped using amplified rDNA restriction analysis (ARDRA) and 16S rRNA gene sequence analysis. The taxonomic composition of the representative genotypes from both rhizosphere and rhizoplane comprised Bacillus, Enterobacter and Pseudomonas. Out of the 10 genotypes, three strains designated as PHP03, CCP05, and TAP02 might be regarded as novel strains based on their low similarity percentages and high bootstrap values. The present study clearly identified specific traits in the isolated rhizobacteria, which make them good candidates as PGPR and might contribute to plant adaption to arid environments. Application of such results in agricultural fields may improve and enhance plant growth in arid soils.

Comparative genome analysis of the Flavobacteriales bacterium strain UJ101, isolated from the gut of Atergatis reticulatus.

PubMed

Yang, Jhung-Ahn; Yang, Sung-Hyun; Kim, Junghee; Kwon, Kae Kyoung; Oh, Hyun-Myung

2017-07-01

Here we report the comparative genomic analysis of strain UJ101 with 15 strains from the family Flavobacteriaceae, using the CGExplorer program. Flavobacteriales bacterium strain UJ101 was isolated from a xanthid crab, Atergatis reticulatus, from the East Sea near Korea. The complete genome of strain UJ101 is a 3,074,209 bp, single, circular chromosome with 30.74% GC content. While the UJ101 genome contains a number of annotated genes for many metabolic pathways, such as the Embden-Meyerhof pathway, the pentose phosphate pathway, the tricarboxylic acid (TCA) cycle, and the glyoxylate cycle, genes for the Entner-Douddoroff pathway are not found in the UJ101 genome. Overall, carbon fixation processes were absent but nitrate reduction and denitrification pathways were conserved. The UJ101 genome was compared to genomes from other marine animals (three invertebrate strains and 5 fish strains) and other marine animal- derived genera. Notable results by genome comparisons showed that UJ101 is capable of denitrification and nitrate reduction, and that biotin-thiamine pathway participation varies among marine bacteria; fish-dwelling bacteria, freeliving bacteria, invertebrate-dwelling bacteria, and strain UJ101. Pan-genome analysis of the 16 strains in this study included 7,220 non-redundant genes that covered 62% of the pan-genome. A core-genome of 994 genes was present and consisted of 8% of the genes from the pan-genome. Strain UJ101 is a symbiotic hetero-organotroph isolated from xanthid crab, and is a metabolic generalist with nitrate-reducing abilities but without the ability to synthesize biotin. There is a general tendency of UJ101 and some fish pathogens to prefer thiamine-dependent glycolysis to gluconeogenesis. Biotin and thiamine auxotrophy or prototrophy may be used as important markers in microbial community studies.

Study of bacterial flora associated with mobile phones of healthcare workers and non-healthcare workers

PubMed Central

Morubagal, Raghavendra Rao; Shivappa, Sowmya Govindanahalli; Mahale, Rashmi Padmanabha; Neelambike, Sumana Mhadevaiah

2017-01-01

Background and Objectives: Despite improvements in modern diagnosis and therapies, hospital acquired infections remain a leading problem of global health systems. Healthcare workers mobile phones is a reservoir for potential pathogens. Despite the high possibility of being contaminated, mobile phones are rarely clean and are often touched during or after examination of patients and handling of specimens without proper hand washing. The main objective of the present study was to isolate, identify different types of bacteria and their antibiotic sensitivity from mobile phones of healthcare workers and non-health-care workers. Materials and Methods: Samples were collected aseptically by rolling over the exposed surfaces of the mobile phones inoculated on the agar plates and incubated aerobically. After incubation, plates were examined for growth. Bacteria were identified and antibiotic sensitivity was tested as per standard microbiological procedures. Results: In this study a total of 175 samples were examined, out of which 125 samples were from healthcare workers (HCWs), 50 samples were from non-healthcare workers (non-HCWs). Among the mobile phones of HCW’s from ICUs, Acinetobacter baumannii (36.84%) was the predominant organism isolated followed by methicillin resistant Staphylococcus aureus (MRSA) (21.05%). Predominant organism isolated from HCW’s in operation theater theater was MRSA (46.66%). Out of 50 worker’s non-HCWs mobile phones samples cultured, 23 (46.00%) samples yielded growth of six different types of bacteria. Conclusion: Our study reveals that there is definite colonization of bacteria on mobile phones of the HCWs. It is not only capable of transferring message but also disease-producing microbes. In order to reduce incidence of nosocomial infections, there should be implementation of hand washing practices and regulations around the use of mobile telephones in hospital settings. PMID:29225753

Study of bacterial flora associated with mobile phones of healthcare workers and non-healthcare workers.

PubMed

Morubagal, Raghavendra Rao; Shivappa, Sowmya Govindanahalli; Mahale, Rashmi Padmanabha; Neelambike, Sumana Mhadevaiah

2017-06-01

Despite improvements in modern diagnosis and therapies, hospital acquired infections remain a leading problem of global health systems. Healthcare workers mobile phones is a reservoir for potential pathogens. Despite the high possibility of being contaminated, mobile phones are rarely clean and are often touched during or after examination of patients and handling of specimens without proper hand washing. The main objective of the present study was to isolate, identify different types of bacteria and their antibiotic sensitivity from mobile phones of healthcare workers and non-health-care workers. Samples were collected aseptically by rolling over the exposed surfaces of the mobile phones inoculated on the agar plates and incubated aerobically. After incubation, plates were examined for growth. Bacteria were identified and antibiotic sensitivity was tested as per standard microbiological procedures. In this study a total of 175 samples were examined, out of which 125 samples were from healthcare workers (HCWs), 50 samples were from non-healthcare workers (non-HCWs). Among the mobile phones of HCW's from ICUs, Acinetobacter baumannii (36.84%) was the predominant organism isolated followed by methicillin resistant Staphylococcus aureus (MRSA) (21.05%). Predominant organism isolated from HCW's in operation theater theater was MRSA (46.66%). Out of 50 worker's non-HCWs mobile phones samples cultured, 23 (46.00%) samples yielded growth of six different types of bacteria. Our study reveals that there is definite colonization of bacteria on mobile phones of the HCWs. It is not only capable of transferring message but also disease-producing microbes. In order to reduce incidence of nosocomial infections, there should be implementation of hand washing practices and regulations around the use of mobile telephones in hospital settings.

Metal resistance mechanisms in Gram-negative bacteria and their potential to remove Hg in the presence of other metals.

PubMed

Giovanella, Patricia; Cabral, Lucélia; Costa, Alexandre Pereira; de Oliveira Camargo, Flávio Anastácio; Gianello, Clesio; Bento, Fátima Menezes

2017-06-01

Contamination of the environment by heavy metals has been increasing in recent years due to industrial activities. Thus research involving microorganisms capable of surviving in multi-contaminated environments is extremely important. The objectives of the present study were to evaluate the removal of mercury alone and in the presence of cadmium, nickel and lead by four mercury-resistant microorganisms; estimate the removal of Cd, Ni and Pb; understand the mechanisms involved (reduction, siderophores, biofilms, biosorption and bioaccumulation) in the metal resistance of the isolate Pseudomonas sp. B50D; and determine the capacity of Pseudomonas sp. B50D in removing Hg, Cd, Ni and Pb from an industrial effluent. It was shown that the four isolates evaluated were capable of removing from 62% to 95% of mercury from a culture medium with no addition of other metals. The isolate Pseudomonas sp. B50D showed the best performance in the removal of mercury when evaluated concomitantly with other metals. This isolate was capable of removing 75% of Hg in the presence of Cd and 91% in the presence of Ni and Pb. With respect to the other metals it removed 60%, 15% and 85% of Cd, Ni and Pb, respectively. In tests with effluent, the isolate Pseudomonas sp. B50D removed 85% of Hg but did not remove the other metals. This isolate presented reduction, biosorption, biofilm production and siderophore production as its metal resistance mechanisms. Pseudomonas sp. B50D was thus a candidate with potential for application in the bioremediation of effluents with complex metal contaminations. Copyright © 2017 Elsevier Inc. All rights reserved.

Isolation and identification of chitinolytic bacteria of pohara river of South East Sulawesi and the optimization production of chitinase enzyme

NASA Astrophysics Data System (ADS)

Halimahtussadiyah, R.; Natsir, Muh.; Kurniawati, Desy; Utamy, Sukma Puspita

2017-03-01

Isolation and identification of chitinolytic bacteria from pohara river and optimation of chitinase enzyme production has been conducted. The aims of the study were isolation, characterize and optimaze of chitinase enzyme production. This study was carried out in three stages; isolation and selection of chitinolytic bacteria, characterization and identification of selected bacteria; optimization of the production of the enzyme (substrate concentration, temperature, and pH), and the determination of growth curve of T3 isolate. The chitinase activity assay was carried out using Schales method. The results of the screening obtained 6 isolates of potential bacteria of chitinolytic. The T3 isolate then was selected for the enzyme production, because it had the highest chitinolytic index of 22.31 mm. The morphological and biochemical observation showed that T3 isolate as a group of bacteria Aerobacter with Gram-negative nature, and shaped bacillus. The optimum condition for chitinase enzyme production was in chitin substrat concentration 0.06%, temperature of 30°C, and pH of 6.

Development of a biosensor for caffeine.

PubMed

Babu, V R Sarath; Patra, S; Karanth, N G; Kumar, M A; Thakur, M S

2007-01-23

We have utilized a microbe, which can degrade caffeine to develop an Amperometric biosensor for determination of caffeine in solutions. Whole cells of Pseudomonas alcaligenes MTCC 5264 having the capability to degrade caffeine were immobilized on a cellophane membrane with a molecular weight cut off (MWCO) of 3000-6000 by covalent crosslinking method using glutaraledhyde as the bifunctional crosslinking agent and gelatin as the protein based stabilizing agent (PBSA). The biosensor system was able to detect caffeine in solution over a concentration range of 0.1 to 1 mg mL(-1). With read-times as short as 3 min, this caffeine biosensor acts as a rapid analysis system for caffeine in solutions. Interestingly, successful isolation and immobilization of caffeine degrading bacteria for the analysis of caffeine described here was enabled by a novel selection strategy that incorporated isolation of caffeine degrading bacteria capable of utilizing caffeine as the sole source of carbon and nitrogen from soils and induction of caffeine degrading capacity in bacteria for the development of the biosensor. This biosensor is highly specific for caffeine and response to interfering compounds such as theophylline, theobromine, paraxanthine, other methyl xanthines and sugars was found to be negligible. Although a few biosensing methods for caffeine are reported, they have limitations in application for commercial samples. The development and application of new caffeine detection methods remains an active area of investigation, particularly in food and clinical chemistry. The optimum pH and temperature of measurement were 6.8 and 30+/-2 degrees C, respectively. Interference in analysis of caffeine due to different substrates was observed but was not considerable. Caffeine content of commercial samples of instant tea and coffee was analyzed by the biosensor and the results compared well with HPLC analysis.

Multiple antibiotic resistant Escherichia coli from a tropical rain forest stream

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carrasco, C.E.; Alvarez, H.J.; Ortiz, N.

1988-12-31

High densities of fecal coliforms were obtained from a pristine site and sewage contaminated site in a tropical rain forest watershed in Puerto Rico. Confirmation of fecal coliform isolates as Escherichia coli was significantly lower than for temperate waters. Antibiotic resistance and multiple antibiotic resistance were common for isolates at both sites; however, the site receiving sewage effluent had a greater proportion of multiple antibiotic resistant isolates. R. plasmids were recovered from 4 MAR isolates, 2 from each site. All recovered plasmids were approximately 1 kilobase. The recovered plasmid were also capable of transforming E. coli HB101 in vitro. Themore » high concentrations of enterobacteriaceae, small R-plasmid size, R-plasmid transformability, and long term survival of fecal origin bacteria in tropical freshwater environments give increasing importance to adequate sewage treatment, and better indicator monitoring methods for tropical areas.« less

Thin Layer Chromatography-Bioautography and Gas Chromatography-Mass Spectrometry of Antimicrobial Leaf Extracts from Philippine Piper betle L. against Multidrug-Resistant Bacteria.

PubMed

Valle, Demetrio L; Puzon, Juliana Janet M; Cabrera, Esperanza C; Rivera, Windell L

2016-01-01

This study isolated and identified the antimicrobial compounds of Philippine Piper betle L. leaf ethanol extracts by thin layer chromatography- (TLC-) bioautography and gas chromatography-mass spectrometry (GC-MS). Initially, TLC separation of the leaf ethanol extracts provided a maximum of eight compounds with R f values of 0.92, 0.86, 0.76, 0.53, 0.40, 0.25, 0.13, and 0.013, best visualized when inspected under UV 366 nm. Agar-overlay bioautography of the isolated compounds demonstrated two spots with R f values of 0.86 and 0.13 showing inhibitory activities against two Gram-positive multidrug-resistant (MDR) bacteria, namely, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus. The compound with an R f value of 0.86 also possessed inhibitory activity against Gram-negative MDR bacteria, namely, carbapenem-resistant Enterobacteriaceae-Klebsiella pneumoniae and metallo-β-lactamase-producing Acinetobacter baumannii. GC-MS was performed to identify the semivolatile and volatile compounds present in the leaf ethanol extracts. Six compounds were identified, four of which are new compounds that have not been mentioned in the medical literature. The chemical compounds isolated include ethyl diazoacetate, tris(trifluoromethyl)phosphine, heptafluorobutyrate, 3-fluoro-2-propynenitrite, 4-(2-propenyl)phenol, and eugenol. The results of this study could lead to the development of novel therapeutic agents capable of dealing with specific diseases that either have weakened reaction or are currently not responsive to existing drugs.

Thin Layer Chromatography-Bioautography and Gas Chromatography-Mass Spectrometry of Antimicrobial Leaf Extracts from Philippine Piper betle L. against Multidrug-Resistant Bacteria

PubMed Central

Valle, Demetrio L.; Puzon, Juliana Janet M.; Cabrera, Esperanza C.

2016-01-01

This study isolated and identified the antimicrobial compounds of Philippine Piper betle L. leaf ethanol extracts by thin layer chromatography- (TLC-) bioautography and gas chromatography-mass spectrometry (GC-MS). Initially, TLC separation of the leaf ethanol extracts provided a maximum of eight compounds with R f values of 0.92, 0.86, 0.76, 0.53, 0.40, 0.25, 0.13, and 0.013, best visualized when inspected under UV 366 nm. Agar-overlay bioautography of the isolated compounds demonstrated two spots with R f values of 0.86 and 0.13 showing inhibitory activities against two Gram-positive multidrug-resistant (MDR) bacteria, namely, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus. The compound with an R f value of 0.86 also possessed inhibitory activity against Gram-negative MDR bacteria, namely, carbapenem-resistant Enterobacteriaceae-Klebsiella pneumoniae and metallo-β-lactamase-producing Acinetobacter baumannii. GC-MS was performed to identify the semivolatile and volatile compounds present in the leaf ethanol extracts. Six compounds were identified, four of which are new compounds that have not been mentioned in the medical literature. The chemical compounds isolated include ethyl diazoacetate, tris(trifluoromethyl)phosphine, heptafluorobutyrate, 3-fluoro-2-propynenitrite, 4-(2-propenyl)phenol, and eugenol. The results of this study could lead to the development of novel therapeutic agents capable of dealing with specific diseases that either have weakened reaction or are currently not responsive to existing drugs. PMID:27478476

Sulfate-reducing bacteria mediate thionation of diphenylarsinic acid under anaerobic conditions.

PubMed

Guan, Ling; Shiiya, Ayaka; Hisatomi, Shihoko; Fujii, Kunihiko; Nonaka, Masanori; Harada, Naoki

2015-02-01

Diphenylarsinic acid (DPAA) is often found as a toxic intermediate metabolite of diphenylchloroarsine or diphenylcyanoarsine that were produced as chemical warfare agents and were buried in soil after the World Wars. In our previous study Guan et al. (J Hazard Mater 241-242:355-362, 2012), after application of sulfate and carbon sources, anaerobic transformation of DPAA in soil was enhanced with the production of diphenylthioarsinic acid (DPTAA) as a main metabolite. This study aimed to isolate and characterize anaerobic soil microorganisms responsible for the metabolism of DPAA. First, we obtained four microbial consortia capable of transforming DPAA to DPTAA at a high transformation rate of more than 80% after 4 weeks of incubation. Sequencing for the bacterial 16S rRNA gene clone libraries constructed from the consortia revealed that all the positive consortia contained Desulfotomaculum acetoxidans species. In contrast, the absence of dissimilatory sulfite reductase gene (dsrAB) which is unique to sulfate-reducing bacteria was confirmed in the negative consortia showing no DPAA reduction. Finally, strain DEA14 showing transformation of DPAA to DPTAA was isolated from one of the positive consortia. The isolate was assigned to D. acetoxidans based on the partial 16S rDNA sequence analysis. Thionation of DPAA was also carried out in a pure culture of a known sulfate-reducing bacterial strain, Desulfovibrio aerotolerans JCM 12613(T). These facts indicate that sulfate-reducing bacteria are microorganisms responsible for the transformation of DPAA to DPTAA under anaerobic conditions.

Use of thermophilic bacteria for bioremediation of petroleum contaminants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Al-Maghrabi, I.M.A.; Bin Aqil, A.O.; Chaalal, O.

1999-01-01

Several strains of thermophilic bacteria were isolated from the environment of the United Arab Emirates. These bacteria show extraordinary resistance to heat and have their maximum growth rate around 60--80 C. This article investigates the potential of using these facultative bacteria for both in situ and ex situ bioremediation of petroleum contaminants. In a series of batch experiments, bacterial growth was observed using a computer image analyzer following a recently developed technique. These experiments showed clearly that the growth rate is enhanced in the presence of crude oil. This is coupled with a rapid degradation of the crude oil. Thesemore » bacteria were found to be ideal for breaking down long-chain organic molecules at a temperature of 40 C, which is the typical ambient temperature of the Persian Gulf region. The same strains of bacteria are also capable of surviving in the presence of the saline environment that can prevail in both sea water and reservoir connate water. This observation prompted further investigation into the applicability of the bacteria in microbial enhanced oil recovery. In the United Arab Emirates, the reservoirs are typically at a temperature of around 85 C. Finally, the performance of the bacteria is tested in a newly developed bioreactor that uses continuous aeration through a transverse slotted pipe. This reactor also uses mixing without damaging the filamentous bacteria. In this process, the mechanisms of bioremediation are identified.« less

Investigation of N-acyl homoserine lactone (AHL) molecule production in Gram-negative bacteria isolated from cooling tower water and biofilm samples.

PubMed

Haslan, Ezgi; Kimiran-Erdem, Ayten

2013-09-01

In this study, 99 Gram-negative rod bacteria were isolated from cooling tower water, and biofilm samples were examined for cell-to-cell signaling systems, N-acyl homoserine lactone (AHL) signal molecule types, and biofilm formation capacity. Four of 39 (10 %) strains isolated from water samples and 14 of 60 (23 %) strains isolated from biofilm samples were found to be producing a variety of AHL signal molecules. It was determined that the AHL signal molecule production ability and the biofilm formation capacity of sessile bacteria is higher than planktonic bacteria, and there was a statistically significant difference between the AHL signal molecule production of these two groups (p < 0.05). In addition, it was found that bacteria belonging to the same species isolated from cooling tower water and biofilm samples produced different types of AHL signal molecules and that there were different types of AHL signal molecules in an AHL extract of bacteria. In the present study, it was observed that different isolates of the same strains did not produce the same AHLs or did not produce AHL molecules, and bacteria known as AHL producers did not produce AHL. These findings suggest that detection of signal molecules in bacteria isolated from cooling towers may contribute to prevention of biofilm formation, elimination of communication among bacteria in water systems, and blockage of quorum-sensing controlled virulence of these bacteria.

Screening and characterization of phosphate solubilizing bacteria from isolate of thermophilic bacteria

NASA Astrophysics Data System (ADS)

Yulianti, Evy; Rakhmawati, Anna

2017-08-01

The aims of this study were to select bacteria that has the ability to dissolve phosphate from thermophilic bacteria isolates after the Merapi eruption. Five isolates of selected bacteria was characterized and continued with identification. Selection was done by using a pikovskaya selective medium. Bacterial isolates were grown in selective medium and incubated for 48 hours at temperature of 55 ° C. Characterization was done by looking at the cell and colony morphology, physiological and biochemical properties. Identification was done with the Profile Matching method based on the reference genus Oscillospira traced through Bergey's Manual of Determinative Bacteriology. Dendogram was created based on similarity index SSM. The results showed there were 14 isolates of bacteria that were able to dissolve phosphate indicated by a clear zone surrounding the bacterial colony on selective media. Five isolates were selected with the largest clear zone. Isolates D79, D92, D110a, D135 and D75 have different characters. The result of phenotypic characters identification with Genus Oscillospira profile has a percentage of 100% similarity to isolate D92 and D110a; 92.31% for isolates D79, and 84.6% for isolates D75 and D135. Dendogram generated from average linkage algorithm / UPGMA using the Simple Matching Coefficient (SSM) algorithms showed, isolate thermophilic bacteria D75 and D135 are combined together to form cluster 1. D110a and D92 form a sub cluster A. Sub cluster A and D79 form cluster 2

X-ray photoelectron spectroscopic evidence for bacteria-enhanced dissolution of hornblende

NASA Astrophysics Data System (ADS)

Kalinowski, B. E.; Liermann, L. J.; Brantley, S. L.; Barnes, A.; Pantano, C. G.

2000-04-01

An Arthrobacter species capable of extracting Fe from hornblende was isolated from a soil from the Adirondacks, NY (USA). This bacteria isolate, used in batch experiments with hornblende, accelerated the release of Fe from hornblende without measurably affecting Al release. The isolate produces both low molecular weight organic acids (LMWOA) and a catecholate siderophore. Polished hornblende (glass and crystal) discs were analyzed with X-ray photoelectron spectroscopy (XPS) before and after incubation with growing Arthrobacter sp. to investigate whether the bacteria caused a distinguishable chemical signature on the upper 100 Å of mineral surface. After removal of the arthrobacter grown on hornblende crystal or glass substrates using lysozyme, XPS revealed surface depletion of Fe for samples grown for several days in buffered (crystal) and unbuffered (crystal and glass) media. Fe/Si ratios of hornblende surfaces dissolved under biotic conditions are significantly lower than Fe/Si ratios on surfaces dissolved under abiotic conditions for similar amounts of time. Enhanced Fe release and the formation of Fe-depleted surfaces is inferred to be caused by catechol complexation at the mineral surface. Because natural siderophore was not isolated in sufficient quantities to run bacteria-free leaching experiments, parallel investigations were run with a commercially available siderophore (desferrioxamine B). Desferrioxamine B was observed to enhance release of Fe, Si, and Al from hornblende both with and without added bacteria. Formation of desferrioxamine-Fe surface complexes were probed by studying the multiple splitting and shift in intensities of the N 1s line analyzed by XPS on siderophore ± Fe on gold surfaces and siderophore + hornblende crystal surfaces. Based upon the observed formation of an hydroxamate (desferrioxamine) surface complex on hornblende, we infer that catecholate siderophores, such as those produced by the arthrobacter, also complex on the hornblende surface. Surface complexation is favored because of the extremely high association constants for siderophore + Fe(III). X-ray photoelectron spectroscopic data is therefore consistent with a model wherein enhanced Fe release by these bacteria or desferrioxamine B is caused by Fe-siderophore complexation at the silicate surface. Such complexation presumably weakens bonds between the Fe and the oxide lattice, causing enhanced Fe leaching and an Fe-depleted surface. Some leaching may also be due to LMWOA, although this is interpreted to be of secondary importance.

Manganese Oxidizing Bacteria in Guaymas Basin Hydrothermal Fluids, Sediments, and Plumes

NASA Astrophysics Data System (ADS)

Dick, G. J.; Tebo, B. M.

2002-12-01

The active seafloor hydrothermal system at Guaymas Basin in the Gulf of California is unique in that spreading centers are covered with thick sediments, and hydrothermal fluids are injected into a semi-enclosed basin. This hydrothermal activity is the source of a large input of dissolved manganese [Mn(II)] into Guaymas Basin, and the presence of a large standing stock of particulate manganese in this basin has been taken as evidence for a short residence time of dissolved Mn(II) with respect to oxidation, suggestive of bacterial catalysis. During a recent Atlantis/Alvin expedition (R/V Atlantis Cruise #7, Leg 11, Jim Cowen Chief Scientist), large amounts of particulate manganese oxides were again observed in Guaymas Basin hydrothermal plumes. The goal of the work presented here was to identify bacteria involved in the oxidation of Mn(II) in Guaymas Basin, and to determine what molecular mechanisms drive this process. Culture-based methods were employed to isolate Mn(II)-oxidizing bacteria from Guaymas Basin hydrothermal fluids, sediments, and plumes, and numerous Mn(II)-oxidizing bacteria were identified based on the formation of orange, brown, or black manganese oxides on bacterial colonies on agar plates. The Mn(II)-oxidizing bacteria were able to grow at temperatures from 12 to 50°C, and a selection of the isolates were chosen for phylogenetic (16S rRNA genes) and microscopic characterization. Endospore-forming Bacillus species accounted for many of the Mn(II)-oxidizing isolates obtained from both hydrothermal sediments and plumes, while members of the alpha- and gamma-proteobacteria were also found. Mn(II)-oxidizing enzymes from previously characterized Bacillus spores are known to be active at temperatures greater than 50°C. The presence of Mn(II)-oxidizing spores - some of which are capable of growing at elevated temperatures - in hydrothermal fluids and sediments at Guaymas Basin suggests that Mn(II) oxidation may be occurring immediately or very soon after hydrothermal fluids emerge from the seafloor.

Abundance and diversity of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)-metabolizing bacteria in UXO-contaminated marine sediments.

PubMed

Zhao, Jian-Shen; Manno, Dominic; Hawari, Jalal

2007-03-01

Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is a toxic explosive known to be resistant to biodegradation. In this study, we found that sediment collected from two unexploded ordnance (UXO) disposal sites (UXO-3, UXO-5) and one nearby reference site (midref) in Hawaii contained anaerobic bacteria capable of removing HMX. Two groups of HMX-removing bacteria were found in UXO-5: group I contained aerotolerant anaerobes and microaerophiles, and group II contained facultative anaerobes. In UXO-3 and midref sediments, HMX-metabolizing bacteria were strictly anaerobic (group III and group IV). Using 16S rRNA sequencing, group I was assigned to a novel phylogenetic cluster of Clostridiales, and groups II and III were related to Paenibacillus and Tepidibacter of Firmicutes, respectively. Group IV bacteria were identified as Desulfovibrio of Deltaproteobacteria. Using [UL-(14)C]-HMX, group IV isolates were found to mineralize HMX (26.8% in 308 d) as determined by liberated (14)CO(2), but negligible mineralization was observed in groups I-III. Resting cells of isolates metabolized HMX to N(2)O and HCHO via the intermediary formation of 1-nitroso-octahydro-3,5,7-trinitro-1,3,5,7-tetrazocine together with methylenedinitramine. These experimental findings suggest that HMX biotransformation occurred either via initial denitration followed by ring cleavage or via reduction of one or more of the N-NO(2) group(s) to the corresponding N-NO bond(s) prior to ring cleavage.

Evaluation of new antibiotic cocktails against contaminating bacteria found in allograft tissues.

PubMed

Serafini, Agnese; Riello, Erika; Trojan, Diletta; Cogliati, Elisa; Palù, Giorgio; Manganelli, Riccardo; Paolin, Adolfo

2016-12-01

Contamination of retrieved tissues is a major problem for allograft safety. Consequently, tissue banks have implemented decontamination protocols to eliminate microorganisms from tissues. Despite the widespread adoption of these protocols, few comprehensive studies validating such methods have been published. In this manuscript we compare the bactericidal activity of different antibiotic cocktails at different temperatures against a panel of bacterial species frequently isolated in allograft tissues collected at the Treviso Tissue Bank Foundation, a reference organization of the Veneto Region in Italy that was instituted to select, recover, process, store and distribute human tissues. We were able to identify at least two different formulations capable of killing most of the bacteria during prolonged incubation at 4 °C.

DITERMINAL OXIDATION OF LONG-CHAIN ALKANES BY BACTERIA1

PubMed Central

Kester, A. S.; Foster, J. W.

1963-01-01

Kester, A. S. (The University of Texas, Austin) and J. W. Foster. Diterminal oxidation of long-chain alkanes by bacteria. J. Bacteriol. 85:859–869. 1963.—A corynebacterial organism capable of growing in mineral salts with individual pure alkanes as carbon sources produces a series of acids from the C10-C14 alkanes. They have been isolated in pure form and identified as monoic, ω-hydroxy monoic, and dioic acids containing the same number of carbon atoms as the substrate alkane. Oxidation took place at both terminal methyl groups—“diterminal oxidation.” Appropriate labeling experiments indicate that omega oxidation of fatty acids occurs in this organism and that an oxygenation with O2 occurs. Images PMID:14044955

In Situ Detection, Isolation, and Physiological Properties of a Thin Filamentous Microorganism Abundant in Methanogenic Granular Sludges: a Novel Isolate Affiliated with a Clone Cluster, the Green Non-Sulfur Bacteria, Subdivision I

PubMed Central

Sekiguchi, Yuji; Takahashi, Hiroki; Kamagata, Yoichi; Ohashi, Akiyoshi; Harada, Hideki

2001-01-01

We previously showed that very thin filamentous bacteria affiliated with the division green non-sulfur bacteria were abundant in the outermost layer of thermophilic methanogenic sludge granules fed with sucrose and several low-molecular-weight fatty acids (Y. Sekiguchi, Y. Kamagata, K. Nakamura, A. Ohashi, H. Harada, Appl. Environ. Microbiol. 65:1280–1288, 1999). Further 16S ribosomal DNA (rDNA) cloning-based analysis revealed that the microbes were classified within a unique clade, green non-sulfur bacteria (GNSB) subdivision I, which contains a number of 16S rDNA clone sequences from various environmental samples but no cultured representatives. To investigate their function in the community and physiological traits, we attempted to isolate the yet-to-be-cultured microbes from the original granular sludge. The first attempt at isolation from the granules was, however, not successful. In the other thermophilic reactor that had been treating fried soybean curd-manufacturing wastewater, we found filamentous microorganisms to outgrow, resulting in the formation of projection-like structures on the surface of granules, making the granules look like sea urchins. 16S rDNA-cloning analysis combined with fluorescent in situ hybridization revealed that the projections were comprised of the uncultured filamentous cells affiliated with the GNSB subdivision I and Methanothermobacter-like cells and the very ends of the projections were comprised solely of the filamentous cells. By using the tip of the projection as the inoculum for primary enrichment, a thermophilic, strictly anaerobic, filamentous bacterium, designated strain UNI-1, was successfully isolated with a medium supplemented with sucrose and yeast extract. The strain was a very slow growing bacterium which is capable of utilizing only a limited range of carbohydrates in the presence of yeast extract and produced hydrogen from these substrates. The growth was found to be significantly stimulated when the strain was cocultured with a hydrogen-utilizing methanogen, Methanothermobacter thermautotrophicus, suggesting that the strain is a sugar-fermenting bacterium, the growth of which is dependent on hydrogen consumers in the granules. PMID:11722931

Antimicrobial properties, antioxidant activity and bioactive compounds from six wild edible mushrooms of western ghats of Karnataka, India

PubMed Central

Ramesh, Ch.; Pattar, Manohar G.

2010-01-01

Methanolic extracts of 6 wild edible mushrooms isolated from the Western Ghats of Karnataka were used in this study. Among the isolates (Lycoperdon perlatum, Cantharellus cibarius, Clavaria vermiculris, Ramaria formosa, Marasmius oreades, Pleurotus pulmonarius), only 4 showed satisfactory results. Quantitative analysis of bioactive components revealed that total phenols are the major bioactive component found in extracts of isolates expressed as mg of GAE per gram of fruit body, which ranged from 3.20 ± 0.05 mg/mL to 6.25 ± 0.08 mg/mL. Average concentration of flavonoid ranged from 0.40 ± 0.052 mg/mL to 2.54 ± 0.08 mg/mL; followed by very small concentration of ascorbic acid (range, 0.06 ± 0.01 mg/mL to 0.16 ± 0.01 mg/mL) in all the isolates. All the isolates showed high phenol and flavonoid content, but ascorbic acid content was found in traces. Antioxidant efficiency by inhibitory concentration on 1,1-Diphenly-2-picrylhydrazyl (DPPH) was found significant when compared to standard antioxidant like Buthylated hydroxyanisol (BHA). The concentration (IC50) ranged from 0.94 ± 0.27 mg/mL to 7.57 ± 0.21 mg/mL. Determination of antimicrobial activity profile of all the isolates tested against a panel of standard pathogenic bacteria and fungi indicated that the concentrations of bioactive components directly influence the antimicrobial capability of the isolates. Agar diffusion assay showed considerable activity against all bacteria. Minimum inhibitory concentration values of the extracts of 4 isolates showed that they are also active even in least concentrations. These results are discussed in relation to therapeutic value of the studied mushrooms. PMID:21808550

Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: evaluation of the probiotic potential.

PubMed

Furtado, Danielle N; Todorov, Svetoslav D; Landgraf, Mariza; Destro, Maria T; Franco, Bernadette D G M

2014-01-01

Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its probiotic potential. Lc. lactis DF4Mi was resistant to acidic pH and oxbile, presented co-aggregation with Listeria monocytogenes, and was not affected by several drugs from different generic groups, being sensitive to most tested antibiotics. These properties indicate that this Lc. lactis strain can be used for enhancement of dairy foods safety and quality, in combination with potential probiotic properties.

Screening of entomopathogenic Metarhizium anisopliae isolates and proteomic analysis of secretion synthesized in response to cowpea weevil (Callosobruchus maculatus) exoskeleton.

PubMed

Murad, André M; Laumann, Raul A; Lima, Thaina de A; Sarmento, Rubia B C; Noronha, Eliane F; Rocha, Thales L; Valadares-Inglis, Maria C; Franco, Octávio L

2006-01-01

Cowpea crops are severely attacked by Callosobruchus maculatus, a Coleopteran that at the larval stage penetrates into stored seeds and feeds on cotyledons. Cowpea weevil control could be based in utilization of bacteria and fungi to reduce pest development. Entomopathogenic fungi, such as Metarhizium anisopliae, are able to control insect-pests and are widely applied in biological control. This report evaluated ten M. anisopliae isolates according to their virulence, correlating chitinolytic, proteolytic and alpha-amylolytic activities, as well proteomic analysis by two dimensional gels of fungal secretions in response to an induced medium containing C. maculatus shells, indicating novel biotechnological tools capable of improving cowpea crop resistance.

Mineralization of a Malaysian crude oil by Pseudomonas sp. and Achromabacter sp. isolated from coastal waters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmad, J.; Ahmad, M.F.

1995-12-31

Regarded as being a potentially effective tool to combat oil pollution, bioremediation involves mineralization, i.e., the conversion of complex hydrocarbons into harmless CO{sub 2} and water by action of microorganisms. Therefore, in achieving optimum effectiveness from the application of these products on crude oil in local environments, the capability of the bacteria to mineralize hydrocarbons was evaluated. The microbial laboratory testing of mineralization on local oil degraders involved, first, isolation of bacteria found at a port located on the west coast of Peninsular Malaysia. Subsequently, these bacteria were identified by means of Biomereux`s API 20E and 20 NE systems andmore » later screened by their growth on a Malaysian crude oil. Selected strains of Pseudomonas sp. and Achromabacter sp. were then exposed individually to a similar crude oil in a mineralization unit and monitored for 16 days for release of CO{sub 2}. Pseudomonas paucimobilis was found to produce more CO{sub 2} than Achromobacter sp. When tested under similar conditions, mixed populations of these two taxa produced more CO{sub 2} than that produced by any individual strain. Effective bioremediation of local crude in Malaysian waters can therefore be achieved from biochemically developed Pseudomonas sp. strains.« less

Mercury-resistance and mercuric reductase activity in Chromobacterium, Erwinia, and Bacillus species

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trevors, J.T.

1987-06-01

Mercury resistant bacteria have been the most extensively studied of all the metal-tolerant bacteria. Mercury resistance is usually mediated by two distinctly different enzymes encoded by plasmids. Mercuric reductase reduces Hg/sup 2 +/ to metallic mercury (Hg/sup 0/). Organomercurial lyases have a molecular weight of 20,000 to 40,000, are composed of 1 or 2 subunits and require the presence of thiol. Plasmic-encoded Hg/sup 2 +/ resistance and mercuric reductase activity have not been detected in many species of bacteria. A Chromobacterium, Erwinia and Bacillus species isolated from environmental samples were capable of growth in the presence of 50 ..mu..M HgCl/submore » 2/. Cell-free extracts of the 3 organisms exhibited mercuric reductase activity that oxidized NADPH in the presence of HgCl/sub 2/. Negligible oxidation of NADPH was observed in the absence of HgCl/sub 2/. The Chromobacterium sp. did not contain any plasmid DNA. This would suggest that Hg/sup 2 +/ resistance was carried on the chromosome in Chromobacterium. A single 3 Mdal plasmid in the Bacillus sp. was refractory to curing. The Erwinia sp. contained 3 plasmids which were also refractory to curing. The location of the resistance genes is unknown in the Bacillus and Erwinia isolates.« less

In Vitro Characterization of Lactic Acid Bacteria Isolated from Bovine Milk as Potential Probiotic Strains to Prevent Bovine Mastitis.

PubMed

Pellegrino, Matías S; Frola, Ignacio D; Natanael, Berardo; Gobelli, Dino; Nader-Macias, María E F; Bogni, Cristina I

2018-01-02

Bovine mastitis causes economic losses on dairy farms worldwide. Lactic acid bacteria (LAB) in animal health are an alternative tool to avoid antibiotic therapy on the prevention of bovine mastitis. In previous studies, 12 LAB isolated from bovine milk were selected taking into account some of the following characteristics: hydrophobicity, auto aggregative capability, inhibition of indicator pathogens, hydrogen peroxide, and capsular polysaccharide production. These LAB were considered because of their beneficial properties. In this work, we also analyzed the antimicrobial activity and the co-aggregation against mastitis causing bacteria, auto-inhibition, adhesion to bovine teat canal epithelial cells (BTCEC), and growth kinetic curves for the 12 LAB. Two of them, Lactococcus lactis subsp. lactis CRL 1655 and Lactobacillus perolens CRL 1724, were selected because they had an interesting pattern of adhesion to BTEC, the inhibition of pathogens and the co-aggregation with the 100% of the assayed pathogens. They showed a predictable difference in the PFGE genomic pattern bands. The kinetic growth of these two strains was similar between them and with the rest of the assayed LAB. The strains selected in the present study showed indispensable characteristics for their inclusion in a probiotic formulation to be used at dry-off period for the prevention of bovine mastitis.

Monitoring the degradation capability of novel haloalkaliphilic tributyltin chloride (TBTCl) resistant bacteria from butyltin-polluted site.

PubMed

Hassan, Hamdy A; Dawah, Somya E; El-Sheekh, Mostafa M

2018-03-28

Tributyltin (TBT) is recognized as a major environmental problem at a global scale. Haloalkaliphilic tributyltin (TBT)-degrading bacteria may be a key factor in the remediation of TBT polluted sites. In this work, three haloalkaliphilic bacteria strains were isolated from a TBT-contaminated site in the Mediterranean Sea. After analysis of the 16S rRNA gene sequences the isolates were identified as Sphingobium sp. HS1, Stenotrophomonas chelatiphaga HS2 and Rhizobium borbori HS5. The optimal growth conditions for biodegradation of TBT by the three strains were pH 9 and 7% (w/v) salt concentration. S. chelatiphaga HS2 was the most effective TBT degrader and has the ability to transform most TBT into dibutyltin and monobutyltin (DBT and MBT). A gene was amplified from strain HS2 and identified as TBTB-permease-like, that encodes an ArsB-permease. A reverse transcription polymerase chain reaction analysis in the HS2 strain confirmed that the TBTB-permease-like gene contributes to TBT resistance. The three novel haloalkaliphilic TBT degraders have never been reported previously. Copyright © 2018 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Proteomics in the study of the molecular taxonomy and epidemiology of bacterial pathogens.

PubMed

Cash, Phillip

2009-06-01

The ability to discriminate bacterial isolates is important for a number of areas of research in Medical Microbiology, particularly in defining bacterial taxonomy and monitoring transmission in epidemiological investigations. Molecular techniques capable of typing bacteria at the level of the genome and proteome are now widely used for these investigations. This review considers two electrophoretic methods for typing bacteria on the basis of their proteomes, namely 1-D SDS-PAGE and 2-DE. The application of these two techniques for bacterial typing is described with reference to two publications that appeared in Electrophoresis [Costa, Electrophoresis 1990, 11, 382-391 and Cash et al., Electrophoresis 1997, 18, 1472-1482]. Even though these methods have been used for nearly 20 years to differentiate bacterial isolates they remain key technologies in proteome-based typing methods. The developments that have arisen from the two key papers are described in order to highlight the advantages and disadvantages in typing bacteria at the level of their proteomes. Some of the difficulties associated with electrophoretic typing methods can be overcome by using non-gel proteomic methods based on MS to provide improved sensitivity and specificity. The application of proteomic methods to investigate bacterial taxonomy, epidemiology and pathogenesis in general has significant potential in furthering our understanding of infectious diseases.

Method of dispersing a hydrocarbon using bacteria

DOEpatents

Tyndall, R.L.

1996-09-24

A new protozoan derived microbial consortia and method for their isolation are provided. The isolated consortia and bacteria are useful for treating wastes such as trichloroethylene and trinitrotoluene. The isolated consortia, bacteria, and dispersants are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

How To Live with Phosphorus Scarcity in Soil and Sediment: Lessons from Bacteria

PubMed Central

Tapia-Torres, Yunuen; Rodríguez-Torres, Maria Dolores; Islas, Africa; Souza, Valeria; García-Oliva, Felipe

2016-01-01

ABSTRACT Phosphorus (P) plays a fundamental role in the physiology and biochemistry of all living things. Recent evidence indicates that organisms in the oceans can break down and use P forms in different oxidation states (e.g., +5, +3, +1, and −3); however, information is lacking for organisms from soil and sediment. The Cuatro Ciénegas Basin (CCB), Mexico, is an oligotrophic ecosystem with acute P limitation, providing a great opportunity to assess the various strategies that bacteria from soil and sediment use to obtain P. We measured the activities in sediment and soil of different exoenzymes involved in P recycling and evaluated 1,163 bacterial isolates (mainly Bacillus spp.) for their ability to use six different P substrates. DNA turned out to be a preferred substrate, comparable to a more bioavailable P source, potassium phosphate. Phosphodiesterase activity, required for DNA degradation, was observed consistently in the sampled-soil and sediment communities. A capability to use phosphite (PO33−) and calcium phosphate was observed mainly in sediment isolates. Phosphonates were used at a lower frequency by both soil and sediment isolates, and phosphonatase activity was detected only in soil communities. Our results revealed that soil and sediment bacteria are able to break down and use P forms in different oxidation states and contribute to ecosystem P cycling. Different strategies for P utilization were distributed between and within the different taxonomic lineages analyzed, suggesting a dynamic movement of P utilization traits among bacteria in microbial communities. IMPORTANCE Phosphorus (P) is an essential element for life found in molecules, such as DNA, cell walls, and in molecules for energy transfer, such as ATP. The Valley of Cuatro Ciénegas, Coahuila (Mexico), is a unique desert characterized by an extreme limitation of P and a great diversity of microbial life. How do bacteria in this valley manage to obtain P? We measured the availability of P and the enzymatic activity associated with P release in soil and sediment. Our results revealed that soil and sediment bacteria can break down and use P forms in different oxidation states and contribute to ecosystem P cycling. Even genetically related bacterial isolates exhibited different preferences for molecules, such as DNA, calcium phosphate, phosphite, and phosphonates, as substrates to obtain P, evidencing a distribution of roles for P utilization and suggesting a dynamic movement of P utilization traits among bacteria in microbial communities. PMID:27235437

How To Live with Phosphorus Scarcity in Soil and Sediment: Lessons from Bacteria.

PubMed

Tapia-Torres, Yunuen; Rodríguez-Torres, Maria Dolores; Elser, James J; Islas, Africa; Souza, Valeria; García-Oliva, Felipe; Olmedo-Álvarez, Gabriela

2016-08-01

Phosphorus (P) plays a fundamental role in the physiology and biochemistry of all living things. Recent evidence indicates that organisms in the oceans can break down and use P forms in different oxidation states (e.g., +5, +3, +1, and -3); however, information is lacking for organisms from soil and sediment. The Cuatro Ciénegas Basin (CCB), Mexico, is an oligotrophic ecosystem with acute P limitation, providing a great opportunity to assess the various strategies that bacteria from soil and sediment use to obtain P. We measured the activities in sediment and soil of different exoenzymes involved in P recycling and evaluated 1,163 bacterial isolates (mainly Bacillus spp.) for their ability to use six different P substrates. DNA turned out to be a preferred substrate, comparable to a more bioavailable P source, potassium phosphate. Phosphodiesterase activity, required for DNA degradation, was observed consistently in the sampled-soil and sediment communities. A capability to use phosphite (PO3 (3-)) and calcium phosphate was observed mainly in sediment isolates. Phosphonates were used at a lower frequency by both soil and sediment isolates, and phosphonatase activity was detected only in soil communities. Our results revealed that soil and sediment bacteria are able to break down and use P forms in different oxidation states and contribute to ecosystem P cycling. Different strategies for P utilization were distributed between and within the different taxonomic lineages analyzed, suggesting a dynamic movement of P utilization traits among bacteria in microbial communities. Phosphorus (P) is an essential element for life found in molecules, such as DNA, cell walls, and in molecules for energy transfer, such as ATP. The Valley of Cuatro Ciénegas, Coahuila (Mexico), is a unique desert characterized by an extreme limitation of P and a great diversity of microbial life. How do bacteria in this valley manage to obtain P? We measured the availability of P and the enzymatic activity associated with P release in soil and sediment. Our results revealed that soil and sediment bacteria can break down and use P forms in different oxidation states and contribute to ecosystem P cycling. Even genetically related bacterial isolates exhibited different preferences for molecules, such as DNA, calcium phosphate, phosphite, and phosphonates, as substrates to obtain P, evidencing a distribution of roles for P utilization and suggesting a dynamic movement of P utilization traits among bacteria in microbial communities. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Arsenite as an electron donor for anoxygenic photosynthesis: Description of three strains of Ectothiorhodospria from Mono Lake, California, and Big Soda Lake, Nevada

USGS Publications Warehouse

McCann, Shelley; Boren, Alison; Hernandez-Maldonado, Jaime; Stoneburner, Brendon; Saltikov, Chad W; Stolz, John F.; Oremland, Ronald S.

2017-01-01

Three novel strains of photosynthetic bacteria from the family Ectothiorhodospiraceae were isolated from soda lakes of the Great Basin Desert, USA by employing arsenite (As(III)) as the sole electron donor in the enrichment/isolation process. Strain PHS-1 was previously isolated from a hot spring in Mono Lake, while strain MLW-1 was obtained from Mono Lake sediment, and strain BSL-9 was isolated from Big Soda Lake. Strains PHS-1, MLW-1, and BSL-9 were all capable of As(III)-dependent growth via anoxygenic photosynthesis and contained homologs of arxA, but displayed different phenotypes. Comparisons were made with three related species: Ectothiorhodospira shaposhnikovii DSM 2111, Ectothiorhodospira shaposhnikovii DSM 243T, and Halorhodospira halophila DSM 244. All three type cultures oxidized arsenite to arsenate but did not grow with As(III) as the sole electron donor. DNA–DNA hybridization indicated that strain PHS-1 belongs to the same species as Ect. shaposhnikovii DSM 2111 (81.1% sequence similarity), distinct from Ect. shaposhnikovii DSM 243T (58.1% sequence similarity). These results suggest that the capacity for light-driven As(III) oxidation is a common phenomenon among purple photosynthetic bacteria in soda lakes. However, the use of As(III) as a sole electron donor to sustain growth via anoxygenic photosynthesis is confined to novel isolates that were screened for by this selective cultivation criterion.

Extraordinary Diversity of Immune Response Proteins among Sea Urchins: Nickel-Isolated Sp185/333 Proteins Show Broad Variations in Size and Charge

PubMed Central

Sherman, Lauren S.; Schrankel, Catherine S.; Brown, Kristy J.; Smith, L. Courtney

2015-01-01

Effective protection against pathogens requires the host to produce a wide range of immune effector proteins. The Sp185/333 gene family, which is expressed by the California purple sea urchin Strongylocentrotus purpuratus in response to bacterial infection, encodes a highly diverse repertoire of anti-pathogen proteins. A subset of these proteins can be isolated by affinity to metal ions based on multiple histidines, resulting in one to four bands of unique molecular weight on standard Western blots, which vary depending on the individual sea urchin. Two dimensional gel electrophoresis (2DE) of nickel-isolated protein samples followed by Western blot was employed to detect nickel-isolated Sp185/333 (Ni-Sp185/333) proteins and to evaluate protein diversity in animals before and after immune challenge with marine bacteria. Ni-Sp185/333 proteins of the same molecular weight on standard Western blots appear as a broad complex of variants that differ in pI on 2DE Western blots. The Ni-Sp185/333 protein repertoire is variable among animals, and shows a variety of changes among individual sea urchins in response to immune challenges with both the same and different species of bacteria. The extraordinary diversity of the Ni-Sp185/333 proteins may provide significant anti-pathogen capabilities for sea urchins that survive solely on innate immunity. PMID:26406912

Ruminal tryptophan-utilizing bacteria degrade ergovaline from tall fescue seed extract.

PubMed

Harlow, B E; Goodman, J P; Lynn, B C; Flythe, M D; Ji, H; Aiken, G E

2017-02-01

The objectives of this study were to evaluate degradation of ergovaline in a tall fescue [ (Schreb.) Darbysh.] seed extract by rumen microbiota ex vivo and to identify specific bacteria capable of ergovaline degradation in vitro. Rumen cell suspensions were prepared by harvesting rumen fluid from fistulated wether goats ( = 3), straining, and differential centrifugation. Suspensions were dispensed into anaerobic tubes with added Trypticase with or without extract (∼10 μg kg ergovaline). Suspensions were incubated for 48 h at 39°C. Samples were collected at 0, 24, and 48 h for ergovaline analysis and enumeration of hyper-ammonia producing (HAB) and tryptophan-utilizing bacteria. Ergovaline values were analyzed by repeated measures using the mixed procedure of SAS. Enumeration data were log transformed for statistical analysis. When suspensions were incubated with extract, 11 to 15% of ergovaline disappearance was observed over 48 h ( = 0.02). After 24 h, suspensions with added extract had 10-fold less HAB than controls ( = 0.04), but treatments were similar by 48 h ( = 1.00). However, after 24 h and 48 h, suspensions with extract had 10-fold more tryptophan-utilizing bacteria ( < 0.01) that were later isolated and identified by their 16S RNA gene sequence as . The isolates and other known rumen pure cultures ( JB1, B159, HD4, B, F, MD1, SR) were evaluated for the ability to degrade ergovaline in vitro. Pure culture cell suspensions were incubated as described above and samples were taken at 0 and 48 h for ergovaline analysis. Data were analyzed using the ANOVA procedure of SAS. All HAB, including the isolates, tested degraded ergovaline (54 to 75%; < 0.05). B14 was also able to degrade ergovaline but to a lesser capacity (12%; < 0.05), but all other bacteria tested did not degrade ergovaline. The results of this study indicate which rumen bacteria may play an important role in ergovaline degradation and that microbiological strategies for controlling their activity could have ramifications for fescue toxicosis and other forms of ergotism in ruminants.

Alkaliphilus crotonatoxidans sp. nov., a strictly anaerobic, crotonate-dismutating bacterium isolated from a methanogenic environment.

PubMed

Cao, Xianhua; Liu, Xiaoli; Dong, Xiuzhu

2003-07-01

Two bacterial strains were isolated from methanogenic butyrate-oxidizing mixed cultures. The cells were straight to slightly curved, gram-positive rods that were motile by means of multiple flagella and formed endospores. Growth was observed in the temperature range 15-45 degrees C (optimum 37 degrees C) and pH range 5.5-9.0 (optimum pH 7.5). The novel isolates were strictly anaerobic chemo-organotrophs capable of utilizing yeast extract, peptone, tryptone and a variety of sugars and organic acids, but not glucose. None of the accessory electron acceptors tested (elemental sulfur, thiosulfate or fumarate) improved growth, except crotonate, which was dismutated to butyrate and acetate. The G + C content of the DNA of one of the isolates, strain B11-2T, was 30.6 mol%. Phylogenetic analysis based on 16S rDNA sequence similarity between strain B11-2T and some other strictly anaerobic, spore-forming bacteria indicated that the novel isolates represented a species in cluster XI within the low-GC gram-positive bacteria, being most closely related to Alkaliphilus transvaalensis JCM 10712T. DNA-DNA relatedness between strain B11-2T and A. transvaalensis JCM 10712T was 21%. On the basis of physiological and molecular properties, and cellular fatty acid and cell wall compositions, the novel isolates are proposed to represent a novel species of the genus Alkaliphilus, for which the name Alkaliphilus crotonatoxidans is proposed (type strain B11-2T=AS 1.2897T=JCM 11672T).

Succession sequence of lactic acid bacteria driven by environmental factors and substrates throughout the brewing process of Shanxi aged vinegar.

PubMed

Zheng, Yu; Mou, Jun; Niu, Jiwei; Yang, Shuai; Chen, Lin; Xia, Menglei; Wang, Min

2018-03-01

Lactic acid bacteria (LAB) are essential microbiota for the fermentation and flavor formation of Shanxi aged vinegar, a famous Chinese traditional cereal vinegar that is manufactured using open solid-state fermentation (SSF) technology. However, the dynamics of LAB in this SSF process and the underlying mechanism remain poorly understood. Here, the diversity of LAB and the potential driving factors of the entire process were analyzed by combining culture-independent and culture-dependent methods. Canonical correlation analysis indicated that ethanol, acetic acid, and temperature that result from the metabolism of microorganisms serve as potential driving factors for LAB succession. LAB strains were periodically isolated, and the characteristics of 57 isolates on environmental factor tolerance and substrate utilization were analyzed to understand the succession sequence. The environmental tolerance of LAB from different stages was in accordance with their fermentation conditions. Remarkable correlations were identified between LAB growth and environmental factors with 0.866 of ethanol (70 g/L), 0.756 of acetic acid (10 g/L), and 0.803 of temperature (47 °C). More gentle or harsh environments (less or more than 60 or 80 g/L of ethanol, 5 or 20 g/L of acetic acid, and 30 or 55 °C temperature) did not affect the LAB succession. The utilization capability evaluation of the 57 isolates for 95 compounds proved that strains from different fermentation stages exhibited different predilections on substrates to contribute to the fermentation at different stages. Results demonstrated that LAB succession in the SSF process was driven by the capabilities of environmental tolerance and substrate utilization.

Co-occurrence of genes for aerobic and anaerobic biodegradation of dichloroethane in organochlorine-contaminated groundwater.

PubMed

Munro, Jacob E; Kimyon, Önder; Rich, Deborah J; Koenig, Joanna; Tang, Sihui; Low, Adrian; Lee, Matthew; Manefield, Mike; Coleman, Nicholas V

2017-11-01

1,2-Dichloroethane (DCA) is a problematic groundwater pollutant. Factors influencing the distribution and activities of DCA-degrading bacteria are not well understood, which has hampered their application for bioremediation. Here, we used quantitative PCR to investigate the distribution of putative DCA-dehalogenating bacteria at a DCA-impacted site in Sydney (Australia). The dehalogenase genes dhlA, tceA and bvcA were detected in all groundwater samples (n = 15), while vcrA was found in 11/15 samples. The 16S rRNA gene sequences specific to the dehalogenating genera Dehalobacter, Desulfitobacterium and Dehalogenimonas were detected in 15/15, 13/15 and 13/15 samples, respectively, while Dehalococcoides sequences were found in 9/15 samples. The tceA, bvcA and vcrA genes occurred in the same samples as Dehalococcoides and Dehalobacter. Microcosm experiments confirmed the presence of bacteria capable of dechlorination under anoxic conditions. The abundance of the dhlA gene, which is found in hydrolytic DCA degraders, was positively correlated to the DCA concentration, and was unexpectedly most abundant in samples with low oxygen conditions. A dhlA-containing bacterium isolated from the site (Xanthobacter EL8) was capable of anaerobic growth on DCA under denitrifying conditions. The presence of diverse DCA-dehalogenating bacteria at this site indicates that natural attenuation or biostimulation could be valid approaches for site cleanup. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Isolation of diverse members of the Aquificales from geothermal springs in Tengchong, China.

PubMed

Hedlund, Brian P; Reysenbach, Anna-Louise; Huang, Liuquin; Ong, John C; Liu, Zizhang; Dodsworth, Jeremy A; Ahmed, Reham; Williams, Amanda J; Briggs, Brandon R; Liu, Yitai; Hou, Weiguo; Dong, Hailiang

2015-01-01

The order Aquificales (phylum Aquificae) consists of thermophilic and hyperthermophilic bacteria that are prominent in many geothermal systems, including those in Tengchong, Yunnan Province, China. However, Aquificales have not previously been isolated from Tengchong. We isolated five strains of Aquificales from diverse springs (temperature 45.2-83.3°C and pH 2.6-9.1) in the Rehai Geothermal Field from sites in which Aquificales were abundant. Phylogenetic analysis showed that four of the strains belong to the genera Hydrogenobacter, Hydrogenobaculum, and Sulfurihydrogenibium, including strains distant enough to likely justify new species of Hydrogenobacter and Hydrogenobaculum. The additional strain may represent a new genus in the Hydrogenothermaceae. All strains were capable of aerobic respiration under microaerophilic conditions; however, they had variable capacity for chemolithotrophic oxidation of hydrogen and sulfur compounds and nitrate reduction.

Endospores of halophilic bacteria of the family Bacillaceae isolated from non-saline Japanese soil may be transported by Kosa event (Asian dust storm)

PubMed Central

Echigo, Akinobu; Hino, Miki; Fukushima, Tadamasa; Mizuki, Toru; Kamekura, Masahiro; Usami, Ron

2005-01-01

Background Generally, extremophiles have been deemed to survive in the extreme environments to which they had adapted to grow. Recently many extremophiles have been isolated from places where they are not expected to grow. Alkaliphilic microorganisms have been isolated from acidic soil samples with pH 4.0, and thermophiles have been isolated from samples of low temperature. Numerous moderately halophilic microorganisms, defined as those that grow optimally in media containing 0.5–2.5 Molar (3–15%) NaCl, and halotolerant microorganisms that are able to grow in media without added NaCl and in the presence of high NaCl have been isolated from saline environments such as salterns, salt lakes and sea sands. It has tacitly been believed that habitats of halophiles able to grow in media containing more than 20% (3.4 M) are restricted to saline environments, and no reports have been published on the isolation of halophiles from ordinary garden soil samples. Results We demonstrated that many halophilic bacteria that are able to grow in the presence of 20% NaCl are inhabiting in non-saline environments such as ordinary garden soils, yards, fields and roadways in an area surrounding Tokyo, Japan. Analyses of partial 16S rRNA gene sequences of 176 isolates suggested that they were halophiles belonging to genera of the family Bacillaceae, Bacillus (11 isolates), Filobacillus (19 isolates), Gracilibacillus (6 isolates), Halobacillus (102 isolates), Lentibacillus (1 isolate), Paraliobacillus (5 isolates) and Virgibacillus (17 isolates). Sequences of 15 isolates showed similarities less than 92%, suggesting that they may represent novel taxa within the family Bacillaceae. Conclusion The numbers of total bacteria of inland soil samples were in a range from 1.4 × 107/g to 1.1 × 106/g. One tenth of the total bacteria was occupied by endospore-forming bacteria. Only very few of the endospore-forming bacteria, roughly 1 out of 20,000, are halophilic bacteria. Most of the halophilic bacteria were surviving as endospores in the soil samples, in a range of less than 1 to about 500/g soil. Samples collected from seashore in a city confronting Tokyo Bay gave the total numbers of bacteria and endospores roughly 1000 time smaller than those of inland soil samples. Numbers of halophilic bacteria per gram, however, were almost the same as those of inland soil samples. A possible source of the halophilic endospore originating from Asian dust storms is discussed. PMID:16242015

More Easily Cultivated Than Identified: Classical Isolation With Molecular Identification of Vaginal Bacteria

PubMed Central

Srinivasan, Sujatha; Munch, Matthew M.; Sizova, Maria V.; Fiedler, Tina L.; Kohler, Christina M.; Hoffman, Noah G.; Liu, Congzhou; Agnew, Kathy J.; Marrazzo, Jeanne M.; Epstein, Slava S.; Fredricks, David N.

2016-01-01

Background. Women with bacterial vaginosis (BV) have complex communities of anaerobic bacteria. There are no cultivated isolates of several bacteria identified using molecular methods and associated with BV. It is unclear whether this is due to the inability to adequately propagate these bacteria or to correctly identify them in culture. Methods. Vaginal fluid from 15 women was plated on 6 different media using classical cultivation approaches. Individual isolates were identified by 16S ribosomal RNA (rRNA) gene sequencing and compared with validly described species. Bacterial community profiles in vaginal samples were determined using broad-range 16S rRNA gene polymerase chain reaction and pyrosequencing. Results. We isolated and identified 101 distinct bacterial strains spanning 6 phyla including (1) novel strains with <98% 16S rRNA sequence identity to validly described species, (2) closely related species within a genus, (3) bacteria previously isolated from body sites other than the vagina, and (4) known bacteria formerly isolated from the vagina. Pyrosequencing showed that novel strains Peptoniphilaceae DNF01163 and Prevotellaceae DNF00733 were prevalent in women with BV. Conclusions. We isolated a diverse set of novel and clinically significant anaerobes from the human vagina using conventional approaches with systematic molecular identification. Several previously “uncultivated” bacteria are amenable to conventional cultivation. PMID:27449870

Effect of autochthonous bacteriocin-producing Lactococcus lactis on bacterial population dynamics and growth of halotolerant bacteria in Brazilian charqui.

PubMed

Biscola, Vanessa; Abriouel, Hikmate; Todorov, Svetoslav Dimitrov; Capuano, Verena Sant'Anna Cabral; Gálvez, Antonio; Franco, Bernadette Dora Gombossy de Melo

2014-12-01

Charqui is a fermented, salted and sun-dried meat product, widely consumed in Brazil and exported to several countries. Growth of microorganisms in this product is unlikely due to reduced Aw, but halophilic and halotolerant bacteria may grow and cause spoilage. Charqui is a good source of lactic acid bacteria able to produce antimicrobial bacteriocins. In this study, an autochthonous bacteriocinogenic strain (Lactococcus lactis subsp. lactis 69), isolated from charqui, was added to the meat used for charqui manufacture and evaluated for its capability to prevent the growth of spoilage bacteria during storage up to 45 days. The influence of L. lactis 69 on the bacterial diversity during the manufacturing of the product was also studied, using denaturing gradient gel electrophoresis (DGGE). L. lactis 69 did not affect the counts and diversity of lactic acid bacteria during manufacturing and storage, but influenced negatively the populations of halotolerant microorganisms, reducing the spoilage potential. The majority of tested virulence genes was absent, evidencing the safety and potential technological application of this strain as an additional hurdle to inhibit undesirable microbial growth in this and similar fermented meat products. Copyright © 2014 Elsevier Ltd. All rights reserved.

Regular Wounding in a Natural System: Bacteria Associated With Reproductive Organs of Bedbugs and Their Quorum Sensing Abilities

PubMed Central

Otti, Oliver; Deines, Peter; Hammerschmidt, Katrin; Reinhardt, Klaus

2017-01-01

During wounding, tissues are disrupted so that bacteria can easily enter the host and trigger a host response. Both the host response and bacterial communication can occur through quorum sensing (QS) and quorum sensing inhibition (QSI). Here, we characterize the effect of wounding on the host-associated bacterial community of the bed bug. This is a model system where the male is wounding the female during every mating. Whereas several aspects of the microbial involvement during wounding have been previously examined, it is not clear to what extent QS and QSI play a role. We find that the microbiome differs depending on mating and feeding status of female bedbugs and is specific to the location of isolation. Most organs of bedbugs harbor bacteria, which are capable of both QS and QSI signaling. By focusing on the prokaryotic quorum communication system, we provide a baseline for future research in this unique system. We advocate the bedbug system as suitable for studying the effects of bacteria on reproduction and for addressing prokaryote and eukaryote communication during wounding. PMID:29326722

Taxonomically-linked growth phenotypes during arsenic stress among arsenic resistant bacteria isolated from soils overlying the Centralia coal seam fire

PubMed Central

Dunivin, Taylor K.; Miller, Justine

2018-01-01

Arsenic (As), a toxic element, has impacted life since early Earth. Thus, microorganisms have evolved many As resistance and tolerance mechanisms to improve their survival outcomes given As exposure. We isolated As resistant bacteria from Centralia, PA, the site of an underground coal seam fire that has been burning since 1962. From a 57.4°C soil collected from a vent above the fire, we isolated 25 unique aerobic As resistant bacterial strains spanning seven genera. We examined their diversity, resistance gene content, transformation abilities, inhibitory concentrations, and growth phenotypes. Although As concentrations were low at the time of soil collection (2.58 ppm), isolates had high minimum inhibitory concentrations (MICs) of arsenate and arsenite (>300 mM and 20 mM respectively), and most isolates were capable of arsenate reduction. We screened isolates (PCR and sequencing) using 12 published primer sets for six As resistance genes (AsRGs). Genes encoding arsenate reductase (arsC) and arsenite efflux pumps (arsB, ACR3(2)) were present, and phylogenetic incongruence between 16S rRNA genes and AsRGs provided evidence for horizontal gene transfer. A detailed investigation of differences in isolate growth phenotypes across As concentrations (lag time to exponential growth, maximum growth rate, and maximum OD590) showed a relationship with taxonomy, providing information that could help to predict an isolate’s performance given As exposure in situ. Our results suggest that microbiological management and remediation of environmental As could be informed by taxonomically-linked As tolerance, potential for resistance gene transferability, and the rare biosphere. PMID:29370270

Diversity of lactic acid bacteria from Miang, a traditional fermented tea leaf in northern Thailand and their tannin-tolerant ability in tea extract.

PubMed

Chaikaew, Siriporn; Baipong, Sasitorn; Sone, Teruo; Kanpiengjai, Apinun; Chui-Chai, Naradorn; Asano, Kozo; Khanongnuch, Chartchai

2017-09-01

The microbiota of lactic acid bacteria (LAB) in thirty-five samples of Miang, a traditional fermented tea leaf product, collected from twenty-two different regions of eight provinces in upper northern Thailand was revealed through the culture-dependent technique. A total of 311 presumptive LAB strains were isolated and subjected to clustering analysis based on repetitive genomic element-PCR (rep-PCR) fingerprinting profiles. The majority of the strains belonged to the Lactobacillus genera with an overwhelming predominance of the Lb. plantarum group. Further studies of species-specific PCR showed that 201 of 252 isolates in the Lb. plantarum group were Lb. plantarum which were thus considered as the predominant LAB in Miang, while the other 51 isolates belonged to Lb. pentosus. In contrast to Lb. plantarum, there is a lack of information on the tannase gene and the tea tannin-tolerant ability of Lb. pentosus. Of the 51 Lb. pentosus isolates, 33 were found to harbor the genes encoding tannase and shared 93-99% amino acid identity with tannase obtained from Lb. pentosus ATCC 8041 T . Among 33 tannase gene-positive isolates, 23 isolates exhibited high tannin- tolerant capabilities when cultivated on de Man Rogosa and Sharpe agar-containing bromocresol purple (0.02 g/L, MRS-BCP) supplemented with 20% (v/v) crude tea extract, which corresponded to 2.5% (w/v) tannins. These Lb. pentosus isolates with high tannin-tolerant capacity are expected to be the high potential strains for functional tannase production involved in Miang fermentation as they will bring about certain benefits and could be used to improve the fermentation of tea products.

Phenotypic Tests for the Detection of β-Lactamase-Producing Enterobacteriaceae Isolated from Different Environments.

PubMed

de Oliveira, Daniele V; Van Der Sand, Sueli T

2016-07-01

Some bacteria from the Enterobacteriaceae family are showing a significant capability to disseminate β-lactams resistance mechanisms among them, and these same mechanisms can be carried out from the hospital environment to superficial water. The aim of this study was to evaluate different phenotypic methods for the detection β-lactamases production by enterobacteria isolated from the anthropogenic environment: hospital wastewater and from a stream that cross the city of Porto Alegre. The applied tests were the modified Hodge test (MHT) and phenotypic tests with the following inhibitors: carbapenemase-phenylboronic acid (APB), metallo-β-lactamase-EDTA, AmpC β-lactamase-cloxacillin, and the confirmatory test for extended-spectrum β-lactamase (ESBL)-clavulanic acid. For this evaluation, 131 isolates were initially subjected to antibiogram using the following antimicrobials: cefotaxime (30 µg), cefpodoxime (10 μg), ceftazidime (30 µg), ertapenem (10 μg), meropenem (10 μg), and aztreonam (30 μg). After this first screening, 62 isolates showed a profile resistance for at least one antimicrobial. These isolates were subjected to all phenotypic tests. Of those, 40 isolates were positive for at least one phenotypic test. In MHT test, one isolate was positive and five were with inconclusive results. The results achieved with the inhibitors are as follows: APB 25/40 positive strains; EDTA 8/40 positive strains; and with CLOXA 2/40 positive strains. ESBL production was observed for 34/40 strains. This assessment shows a high level of bacteria which can produce enzymes that inactivate β-lactams present in the different environment like the stream waters and from the hospital settings.

Isolation and characterization of bacteria from mercury contaminated sites in Rio Grande do Sul, Brazil, and assessment of methylmercury removal capability of a Pseudomonas putida V1 strain.

PubMed

Cabral, Lucélia; Giovanella, Patrícia; Gianello, Clésio; Bento, Fátima Menezes; Andreazza, Robson; Camargo, Flávio Anastácio Oliveira

2013-06-01

Methylmercury (MeHg) is one of the most dangerous heavy metal for living organisms that may be found in environment. Given the crescent industrialization of Brazil and considering that mercury is a residue of several industrial processes, there is an increasing need to encounter and develop remediation approaches of mercury contaminated sites. The aim of this study was to isolate and characterize methylmercury resistant bacteria from soils and sludge sewage from Rio Grande do Sul, Brazil. Sixteen bacteria were isolated from these contaminated sites and some isolates were highly resistant to methylmercury (>8.7 μM). All the isolates were identified by 16S rDNA. Pseudomonas putida V1 was able to volatilize approximately 90 % of methylmercury added to growth media and to resist to copper, lead, nickel, chromate, zinc, cobalt, manganese and barium. In the presence of high concentrations of methylmercury (12 μM), cell growth was limited, but P. putida V1 was still able to remove up to 29 % of this compound from culture medium. This bacterium removed an average of 77 % of methylmercury from culture medium with pH in the range 4.0-6.0. In addition, methylmercury was efficiently removed (>80 %) in temperature of 21-25 °C. Polymerase chain reactions indicated the presence of merA but not merB in P. putida V1. The growth and ability of P. putida V1 to remove methylmercury in a wide range of pH (4.0 and 8.0) and temperature (10-35 °C), its tolerance to other heavy metals and ability to grow in the presence of up to 11.5 μM of methylmercury, suggest this strain as a new potential resource for degrading methylmercury contaminated sites.

The determination and arrangement of a combination of enzyme lactate dehydrogenase of bacteria Acinetobacter sp. as a device the identity important bacteria agent composts

NASA Astrophysics Data System (ADS)

Sukmawati, D.; Puspitaningrum, R.; Muzajjanah

2017-07-01

The number of garbage generated by the industry or society is a usual problem encountered by almost all urban centers, especially large cities such as Jakarta. Waste prevention strategy required quickly and accurately. One strategy for tackling the Junk was getting lactic acid-producing bacteria. It has been shown that lactic acid can increase the acceleration of organic matter such as an overhaul of lignin and cellulose as well as out causing toxic compounds arising from decay. This research will be conducted on the determination and characterization of the enzyme-producing compost bacteria LDH lactate dehydrogenase LDH - which in isolation from the garbage Landfill Rawasari. Methodology: Research carried out consists: isolation of lactic acid-producing bacteria; identification of microscopic, macroscopic and staining Gram; cellulose assay, and optimization of PCR conditions LDH enzymes producing bacteria. Isolation is performed by dilution method and the direct method. As many as 5-point sampling. Each stage is conducted from 10 grams of soil from the top surface of the compost. Isolation results obtained 100 isolate the bacteria. Base on the characteristic of macroscopic and microscopic observations retrieved 14 isolates of bacteria have shaped rods and brought forth a negative kind of Gram positive staining. Bacterial isolates with codes (BK1; BK3; BK4; BK5; BK6; BK7; BK8; BK9; BK10; BK11: BK12; BK 13). The potential bacteria with ability produce lactate dehydrogenase was BK1 and BK3. Base for analysis phylogenetic there was identification bacteria bak1 and bak3 where Acinetobacter sp.

Isolation, identification and characterization of lignin-degrading bacteria from Qinling, China.

PubMed

Yang, C-X; Wang, T; Gao, L-N; Yin, H-J; Lü, X

2017-12-01

Lignin is an aromatic heteropolymer forming a physical barrier and it is a big challenge in biomass utilization. This paper first investigated lignin-degradation bacteria from rotten wood in Qinling Mountain. Nineteen potential strains were selected and ligninolytic enzyme activities were determined over 84 h. Strains that had higher enzyme activities were selected. Further, the biodegradation of wheat straw lignin and alkali lignin was evaluated indicating that Burkholderia sp. H1 had the highest capability. It was confirmed by gel permeation chromatography and field emission scanning electron microscope that alkali lignin was depolymerized into small fragments. The degraded products were analysed using gas chromatography-mass spectrometry. The total ion chromatograph of products treated for 7 days showed the formation of aromatic compounds, an important intermediate from lignin degradation. Interestingly, they disappeared in 15 days while the aldehyde and ester compounds increased. The results suggest that the lignin-degrading bacteria are abundant in rotten wood and strain H1 has high potential to break down lignin. The diversity of lignin-degrading bacteria in Qinling Mountain is revealed. The study of Burkholderia sp. H1 expands the range of bacteria for lignin degradation and provides novel bacteria for application to lignocellulosic biomass. © 2017 The Society for Applied Microbiology.

Phenotypic and phylogenetic characterization of ruminal tannin-tolerant bacteria.

PubMed

Nelson, K E; Thonney, M L; Woolston, T K; Zinder, S H; Pell, A N

1998-10-01

The 16S rRNA sequences and selected phenotypic characteristics were determined for six recently isolated bacteria that can tolerate high levels of hydrolyzable and condensed tannins. Bacteria were isolated from the ruminal contents of animals in different geographic locations, including Sardinian sheep (Ovis aries), Honduran and Colombian goats (Capra hircus), white-tail deer (Odocoileus virginianus) from upstate New York, and Rocky Mountain elk (Cervus elaphus nelsoni) from Oregon. Nearly complete sequences of the small-subunit rRNA genes, which were obtained by PCR amplification, cloning, and sequencing, were used for phylogenetic characterization. Comparisons of the 16S rRNA of the six isolates showed that four of the isolates were members of the genus Streptococcus and were most closely related to ruminal strains of Streptococcus bovis and the recently described organism Streptococcus gallolyticus. One of the other isolates, a gram-positive rod, clustered with the clostridia in the low-G+C-content group of gram-positive bacteria. The sixth isolate, a gram-negative rod, was a member of the family Enterobacteriaceae in the gamma subdivision of the class Proteobacteria. None of the 16S rRNA sequences of the tannin-tolerant bacteria examined was identical to the sequence of any previously described microorganism or to the sequence of any of the other organisms examined in this study. Three phylogenetically distinct groups of ruminal bacteria were isolated from four species of ruminants in Europe, North America, and South America. The presence of tannin-tolerant bacteria is not restricted by climate, geography, or host animal, although attempts to isolate tannin-tolerant bacteria from cows on low-tannin diets failed.

Phenotypic and Phylogenetic Characterization of Ruminal Tannin-Tolerant Bacteria

PubMed Central

Nelson, Karen E.; Thonney, Michael L.; Woolston, Tina K.; Zinder, Stephen H.; Pell, Alice N.

1998-01-01

The 16S rRNA sequences and selected phenotypic characteristics were determined for six recently isolated bacteria that can tolerate high levels of hydrolyzable and condensed tannins. Bacteria were isolated from the ruminal contents of animals in different geographic locations, including Sardinian sheep (Ovis aries), Honduran and Colombian goats (Capra hircus), white-tail deer (Odocoileus virginianus) from upstate New York, and Rocky Mountain elk (Cervus elaphus nelsoni) from Oregon. Nearly complete sequences of the small-subunit rRNA genes, which were obtained by PCR amplification, cloning, and sequencing, were used for phylogenetic characterization. Comparisons of the 16S rRNA of the six isolates showed that four of the isolates were members of the genus Streptococcus and were most closely related to ruminal strains of Streptococcus bovis and the recently described organism Streptococcus gallolyticus. One of the other isolates, a gram-positive rod, clustered with the clostridia in the low-G+C-content group of gram-positive bacteria. The sixth isolate, a gram-negative rod, was a member of the family Enterobacteriaceae in the gamma subdivision of the class Proteobacteria. None of the 16S rRNA sequences of the tannin-tolerant bacteria examined was identical to the sequence of any previously described microorganism or to the sequence of any of the other organisms examined in this study. Three phylogenetically distinct groups of ruminal bacteria were isolated from four species of ruminants in Europe, North America, and South America. The presence of tannin-tolerant bacteria is not restricted by climate, geography, or host animal, although attempts to isolate tannin-tolerant bacteria from cows on low-tannin diets failed. PMID:9758806

The inhibition of Clostridium botulinum type C by other bacteria in wetland sediments

USGS Publications Warehouse

Sandler, Renee J.; Rocke, Tonie E.; Yuill, Thomas M.

1998-01-01

Bacteria with inhibitory activity against Clostridium botulinum type C were isolated from 32% of sediment samples (n = 1600) collected from 10 marshes in a northern California wetland over a 12 mo period. Aerobic and anaerobic bacteria with inhibitory activity were isolated from 12% and 23% of the samples, respectively. Bacteria with inhibitory activity were isolated from all 10 study sites and throughout the year. This study demonstrates that bacteria with inhibitory activity against C. botulinum type C occur naturally in wetland sediments.

Use of mycelia as paths for the isolation of contaminant‐degrading bacteria from soil

PubMed Central

Furuno, Shoko; Remer, Rita; Chatzinotas, Antonis; Harms, Hauke; Wick, Lukas Y.

2012-01-01

Summary Mycelia of fungi and soil oomycetes have recently been found to act as effective paths boosting bacterial mobility and bioaccessibility of contaminants in vadose environments. In this study, we demonstrate that mycelia can be used for targeted separation and isolation of contaminant‐degrading bacteria from soil. In a ‘proof of concept’ study we developed a novel approach to isolate bacteria from contaminated soil using mycelia of the soil oomycete Pythium ultimum as translocation networks for bacteria and the polycyclic aromatic hydrocarbon naphthalene (NAPH) as selective carbon source. NAPH‐degrading bacterial isolates were affiliated with the genera Xanthomonas, Rhodococcus and Pseudomonas. Except for Rhodococcus the NAPH‐degrading isolates exhibited significant motility as observed in standard swarming and swimming motility assays. All steps of the isolation procedures were followed by cultivation‐independent terminal 16S rRNA gene terminal fragment length polymorphism (T‐RFLP) analysis. Interestingly, a high similarity (63%) between both the cultivable NAPH‐degrading migrant and the cultivable parent soil bacterial community profiles was observed. This suggests that mycelial networks generally confer mobility to native, contaminant‐degrading soil bacteria. Targeted, mycelia‐based dispersal hence may have high potential for the isolation of bacteria with biotechnologically useful properties. PMID:22014110

Identification of chitinolytic bacteria isolated from shrimp pond sediment and characterization of their chitinase encoding gene

NASA Astrophysics Data System (ADS)

Triwijayani, A. U.; Puspita, I. D.; Murwantoko; Ustadi

2018-03-01

Chitinolytic bacteria are a group of bacteria owning enzymes that able to hydrolyze chitin. Previously, we isolated chitinolytic bacteria from shrimp pond sediment in Bantul, Yogyakarta, and obtained five isolates showing high chitinolytic index named as isolate PT1, PT2, PT5, PT6 and PB2. The aims of this study were to identify chitinolytic bacteria isolated from shrimp pond sediment and to characterize the chitinase encoding gene from each isolate. The molecular technique was performed by amplification of 16S rDNA, amplification of chitinase encoding gene and sequence analysis. Two chitinolytic bacteria of PT1 and PT2 were similar to Aeromonas bivalvium strain D15, PT5 to Pseudomonas stutzeri strain BD-2.2.1, PT6 to Serratia marcescens strain FZSF02 and PB2 to Streptomyces misionensis strain OsiRt-1. The comparison of chitinase encoding gene between three isolates with those in Gen Bank shows that PT1 had similar sequences with the chi1 gene in Aeromonas sp. 17m, PT2 with chi1 gene in A. caviae (CB101) and PT6 with chiB gene in S. Marcescens (BJL200).

Antimicrobial Activities of Bacteria Associated with the Brown Alga Padina pavonica

PubMed Central

Ismail, Amel; Ktari, Leila; Ahmed, Mehboob; Bolhuis, Henk; Boudabbous, Abdellatif; Stal, Lucas J.; Cretoiu, Mariana Silvia; El Bour, Monia

2016-01-01

Macroalgae belonging to the genus Padina are known to produce antibacterial compounds that may inhibit growth of human- and animal pathogens. Hitherto, it was unclear whether this antibacterial activity is produced by the macroalga itself or by secondary metabolite producing epiphytic bacteria. Here we report antibacterial activities of epiphytic bacteria isolated from Padina pavonica (Peacocks tail) located on northern coast of Tunisia. Eighteen isolates were obtained in pure culture and tested for antimicrobial activities. Based on the 16S rRNA gene sequences the isolates were closely related to Proteobacteria (12 isolates; 2 Alpha- and 10 Gammaproteobacteria), Firmicutes (4 isolates) and Actinobacteria (2 isolates). The antimicrobial activity was assessed as inhibition of growth of 12 species of pathogenic bacteria (Aeromonas salmonicida, A. hydrophila, Enterobacter xiangfangensis, Enterococcus faecium, Escherichia coli, Micrococcus sp., Salmonella typhimurium, Staphylococcus aureus, Streptococcus sp., Vibrio alginoliticus, V. proteolyticus, V. vulnificus) and one pathogenic yeast (Candida albicans). Among the Firmicutes, isolate P8, which is closely related to Bacillus pumilus, displayed the largest spectrum of growth inhibition of the pathogenic bacteria tested. The results emphasize the potential use of P. pavonica associated antagonistic bacteria as producers of novel antibacterial compounds. PMID:27462308

[Community structure and diversity of culturable moderate halophilic bacteria isolated from Qrhan salt lake on Qinghai-Tibet Plateau].

PubMed

Shen, Shuo

2017-04-04

I studied the community structure and diversity of culturable moderate halophilic bacteria isolated from Qrhan Salt Lake. I isolated and cultured the moderate halophilic bacteria on different selective media. After the 16S rRNA gene sequences was amplified and measured, I constructed the phylogenic tree, analyzed the community structure and calculated the diversity indexes according to the 16S rRNA gene information. A total of 421 moderate halophilic bacteria were isolated from water and mud samples in Qrhan Salt Lake. The 16S rRNA gene information showed that 4 potential novel species belonged to the family Bacillaceae. Eighty-three model strains belonged to 3 phylurms 6 families 16 genus. Among them, Bacillus sp., Oceanobacillus sp. and Halomonas sp. were dominant species. Diversity analysis showed that the diversity of strains isolated from water sample was higher than that from mud sample, but the dominance degree of strains isolated from mud sample was higher than that from water sample. The genetic diversity of moderate halophilic bacteria isolated from Qrhan Salt Lake was abundant. Also, there were dominant and novel species of culturable moderate halophilic bacteria in this lake.

Amoeba-Resisting Bacteria and Ventilator-Associated Pneumonia

PubMed Central

La Scola, Bernard; Boyadjiev, Ioanna; Greub, Gilbert; Khamis, Atieh; Martin, Claude

2003-01-01

To evaluate the role of amoeba-associated bacteria as agents of ventilator-associated pneumonia (VAP), we tested the water from an intensive care unit (ICU) every week for 6 months for such bacteria isolates; serum samples and bronchoalveolar lavage samples (BAL) were also obtained from 30 ICU patients. BAL samples were examined for amoeba-associated bacteria DNA by suicide-polymerase chain reaction, and serum samples were tested against ICU amoeba-associated bacteria. A total of 310 amoeba-associated bacteria from10 species were isolated. Twelve of 30 serum samples seroconverted to one amoeba-associated bacterium isolated in the ICU, mainly Legionella anisa and Bosea massiliensis, the most common isolates from water (p=0.021). Amoeba-associated bacteria DNA was detected in BAL samples from two patients whose samples later seroconverted. Seroconversion was significantly associated with VAP and systemic inflammatory response syndrome, especially in patients for whom no etiologic agent was found by usual microbiologic investigations. Amoeba-associated bacteria might be a cause of VAP in ICUs, especially when microbiologic investigations are negative. PMID:12890321

Keratinase from newly isolated strain of thermophilic Bacillus for chicken feed modification

NASA Astrophysics Data System (ADS)

Larasati, Ditya; Tsurayya, Nur; Koentjoro, Maharani Pertiwi; Prasetyo, Endry Nugroho

2017-06-01

Keratinase producing bacteria were isolated from Dieng crater and Mojokerto chicken farm. The screening was done by clear zone method. The strains were selected as they produced clear zones suggesting the presence of keratinolytic activity. The clear zone on FM media depended on both the source and activity of keratinase produced by keratinolytic bacteria. Based on keratinase production and activity, Bacillus sp. SLII-1 was selected for further studies. Keratinase produced by Bacillus sp. SLII-1 capable of producing crude keratinase with 2.08 (mg/second)/ml enzyme activity which able to increase digestibility of feather meal until 22.06% based on soluble protein level. Broiler chicken (Gallus domesticus) that consumed feed containing 5% feather meal indicated production performance of 1194.8 gram/head of feed consumption, 567 gram/head of addition of weight, and 2.1 of feed conversion ratio. An enzymatic engineered chicken feathers waste showed the performance of broiler chicken that is better than soybean meal as conventional sources of protein but could not yet substitute the use of conventional protein sources of fishmeal.

Muddy puddles - the microbiology of puddles located outside tertiary university teaching hospitals.

PubMed

Furukawa, M; McCaughan, J; Stirling, J; Millar, B C; Bell, J; Goldsmith, C E; Reid, A; Misawa, N; Moore, J E

2018-04-01

In the British Isles, the frequency of rain results in the formation of puddles on footpaths and roads in/around hospitals. No data are available demonstrating the microbiological composition of such puddles and therefore a study was undertaken to examine the microbiology of puddles in the grounds of two tertiary university-teaching hospitals (18 sites) and compared with control puddles from non-hospital rural environments (eight sites), estimating (i) total viable count; (ii) identification of organisms in puddles; (iii) enumeration of Escherichia coli: (iv) detection of Extended Spectrum β-Lactamase producing organisms and (v) direct antimicrobial susceptibility testing. A mean count of 2·3 × 10 3  CFU per ml and 1·0 × 10 9  CFU per ml was obtained for hospital and non-hospital puddles respectively. Isolates (n = 77; 54 hospital and 23 non-hospital) were isolated comprising of 23 species among 17 genera (hospital sites), where the majority (10/16; 62·5%) of genera identified were Gram-negative approximately, a fifth (20·6%) were shared by hospital and non-hospital rural samples. Escherichia coli was detected in half of the hospital puddles and under-half (37·5%) of the rural puddles extended spectrum β-lactamase organisms were not detected in any samples examined. Rainwater puddles from the hospital and non-hospital environments contain a diverse range of bacteria, which are capable of causing infections. This study demonstrated the presence of a wide diversity of bacterial taxa associated with rainwater puddles around hospitals, many of which are capable of causing human disease. Of clinical significance is the presence of Pseudomonas aeruginosa isolated from a hospital puddle, particularly for patients with cystic fibrosis. The presence of potentially disease-causing bacteria in puddles in and around hospitals identifies a new potential environmental reservoir of bacteria. Furthermore work is now needed to define their potential of entering or exiting hospital wards by contaminated footwear. © 2018 The Society for Applied Microbiology.

Characterization of culturable bacteria isolated from hot springs for plant growth promoting traits and effect on tomato (Lycopersicon esculentum) seedling.

PubMed

Patel, Kinjal Samir; Naik, Jinal Hardik; Chaudhari, Sejal; Amaresan, Natarajan

2017-04-01

To elucidate the functional diversity of hot spring bacteria, 123 bacteria were isolated and screened for evaluating their multifunctional plant growth promoting (PGP) properties. The antagonistic activity against different phytopathogens showed the presence of a high amount of biocontrol bacteria in the hot springs. During screening for PGP properties, 61.0% isolates showed production of indole acetic acid and 23.6% showed inorganic phosphate solubilization qualitatively. For production of extracellular enzymes, it was found that 61.0% isolates produced lipase, 56.9% produced protease, and 43.9% produced cellulase. In extreme properties, half of the isolates showed tolerance to 5% NaCl (w/v) and 48.8% isolates survived heat shock at 70°C. The identification of 12 multipotential bacteria based on 16S rRNA gene sequencing revealed that the bacteria belonged to Aneurinibacillus aneurinilyticus and Bacillus spp. Bacterization of tomato seeds showed that the hot spring bacteria promoted shoot height, fresh shoot weight, root length, and fresh root weight of tomato seedlings, with values ranging from 3.12% to 74.37%, 33.33% to 350.0%, 16.06% to 130.41%, and 36.36% to 318.18%, respectively, over the control. This research shows that multifunctional bacteria could be isolated from the hot springs. The outcome of this research may have a potential effect on crop production methodologies used in saline and arid environments. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Honey Bees Avoid Nectar Colonized by Three Bacterial Species, But Not by a Yeast Species, Isolated from the Bee Gut

PubMed Central

Good, Ashley P.; Gauthier, Marie-Pierre L.; Vannette, Rachel L.; Fukami, Tadashi

2014-01-01

The gut microflora of the honey bee, Apis mellifera, is receiving increasing attention as a potential determinant of the bees’ health and their efficacy as pollinators. Studies have focused primarily on the microbial taxa that appear numerically dominant in the bee gut, with the assumption that the dominant status suggests their potential importance to the bees’ health. However, numerically minor taxa might also influence the bees’ efficacy as pollinators, particularly if they are not only present in the gut, but also capable of growing in floral nectar and altering its chemical properties. Nonetheless, it is not well understood whether honey bees have any feeding preference for or against nectar colonized by specific microbial species. To test whether bees exhibit a preference, we conducted a series of field experiments at an apiary using synthetic nectar inoculated with specific species of bacteria or yeast that had been isolated from the bee gut, but are considered minor components of the gut microflora. These species had also been found in floral nectar. Our results indicated that honey bees avoided nectar colonized by the bacteria Asaia astilbes, Erwinia tasmaniensis, and Lactobacillus kunkeei, whereas the yeast Metschnikowia reukaufii did not affect the feeding preference of the insects. Our results also indicated that avoidance of bacteria-colonized nectar was caused not by the presence of the bacteria per se, but by the chemical changes to nectar made by the bacteria. These findings suggest that gut microbes may not only affect the bees’ health as symbionts, but that some of the microbes may possibly affect the efficacy of A. mellifera as pollinators by altering nectar chemistry and influencing their foraging behavior. PMID:24466119

Enrichment and identification of polycyclic aromatic compound-degrading bacteria enriched from sediment samples.

PubMed

Long, Rachel M; Lappin-Scott, Hilary M; Stevens, Jamie R

2009-07-01

The degradation of polycyclic aromatic compounds (PACs) has been widely studied. Knowledge of the degradation of PACs by microbial populations can be utilized in the remediation of contaminated sites. To isolate and identify PAC-degrading bacteria for potential use in future bioremediation programmes, we established a series of PAC enrichments under the same experimental conditions from a single sediment sample taken from a highly polluted estuarine site. Enrichment cultures were established using the pollutants: anthracene, phenanthrene and dibenzothiophene as a sole carbon source. The shift in microbial community structure on each of these carbon sources was monitored by analysis of a time series of samples from each culture using 16S rRNA polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Significantly, our findings demonstrate that shifts in the constituent species within each degradative community are directly attributable to enrichment with different PACs. Subsequently, we characterized the microorganisms comprising the degradative communities within each enrichment using 16S rRNA sequence data. Our findings demonstrate that the ability to degrade PACs is present in five divisions of the Proteobacteria and Actinobacteria. By determining the precise identity of the PAC-degrading bacterial species isolated from a single sediment sample, and by comparing our findings with previously published research, we demonstrate how bacteria with similar PAC degrading capabilities and 16S rRNA signatures are found in similarly polluted environments in geographically very distant locations, e.g., China, Italy, Japan and Hawaii. Such a finding suggests that geographical barriers do not limit the distribution of key PAC-degrading bacteria; this finding is in accordance with the Baas-Becking hypothesis "everything is everywhere; the environment selects" and may have significant consequences for the global distribution of PAC-degrading bacteria and their use in bioremediation.

Colloidal precipitates related to Acid Mine Drainage: bacterial diversity and micro fungi-heavy metal interactions

NASA Astrophysics Data System (ADS)

Lucchetti, G.; Carbone, C.; Consani, S.; Zotti, M.; Di Piazza, S.; Pozzolini, M.; Giovine, M.

2015-12-01

In Acid Mine Drainage (AMD) settings colloidal precipitates control the mobility of Potential Toxic Elements (PTEs). Mineral-contaminant relationships (i.e. adsorption, ion-exchange, desorption) are rarely pure abiotic processes. Microbes, mainly bacteria and microfungi, can catalyze several reactions modifying the element speciation, as well as the bioavailability of inorganic pollutants. Soil, sediments, and waters heavily polluted with PTEs through AMD processes are a potential reservoir of extremophile bacteria and fungi exploitable for biotechnological purposes. Two different AMD related colloids, an ochraceous precipitate (deposited in weakly acidic conditions, composed by nanocrystalline goethite) and a greenish-blue precipitate (deposited at near-neutral pH, composed by allophane + woodwardite) were sampled. The aims of this work were to a) characterize the mycobiota present in these colloidal minerals by evaluating the presence of alive fungal propagules and extracting bacteria DNA; b) verify the fungal strains tolerance, and bioaccumulation capability on greenish-blue and ZnSO4 enriched media; c) evaluate potential impact of bacteria in the system geochemistry. The preliminary results show an interesting and selected mycobiota able to survive under unfavourable environmental conditions. A significant number of fungal strains were isolated in pure culture. Among them, species belonging to Penicillium and Trichoderma genera were tested on both greenish-blue and ZnSO4 enriched media. The results show a significant tolerance and bioaccumulation capability to some PTEs. The same colloidal precipitates were processed to extract bacteria DNA by using a specific procedure developed for sediments. The results give a good yield of nucleic acids and a positive PCR amplification of 16S rDNA accomplished the first step for future metagenomic analyses.

More Easily Cultivated Than Identified: Classical Isolation With Molecular Identification of Vaginal Bacteria.

PubMed

Srinivasan, Sujatha; Munch, Matthew M; Sizova, Maria V; Fiedler, Tina L; Kohler, Christina M; Hoffman, Noah G; Liu, Congzhou; Agnew, Kathy J; Marrazzo, Jeanne M; Epstein, Slava S; Fredricks, David N

2016-08-15

Women with bacterial vaginosis (BV) have complex communities of anaerobic bacteria. There are no cultivated isolates of several bacteria identified using molecular methods and associated with BV. It is unclear whether this is due to the inability to adequately propagate these bacteria or to correctly identify them in culture. Vaginal fluid from 15 women was plated on 6 different media using classical cultivation approaches. Individual isolates were identified by 16S ribosomal RNA (rRNA) gene sequencing and compared with validly described species. Bacterial community profiles in vaginal samples were determined using broad-range 16S rRNA gene polymerase chain reaction and pyrosequencing. We isolated and identified 101 distinct bacterial strains spanning 6 phyla including (1) novel strains with <98% 16S rRNA sequence identity to validly described species, (2) closely related species within a genus, (3) bacteria previously isolated from body sites other than the vagina, and (4) known bacteria formerly isolated from the vagina. Pyrosequencing showed that novel strains Peptoniphilaceae DNF01163 and Prevotellaceae DNF00733 were prevalent in women with BV. We isolated a diverse set of novel and clinically significant anaerobes from the human vagina using conventional approaches with systematic molecular identification. Several previously "uncultivated" bacteria are amenable to conventional cultivation. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Prevalence of antimicrobial resistance and integron gene cassettes in Escherichia coli isolated from yaks (Poephagus grunniens) in Aba Tibetan Autonomous Prefecture, China.

PubMed

Yang, Xin; Zou, Wencheng; Zeng, Jinxin; Xie, Shengze; An, Tianwu; Luo, Xiaolin; Chen, Danyu; Feng, Lan; Cheng, Guangyang; Cai, Run; Huang, Qianru; Wang, Hongning

2017-10-01

Escherichia coli (E. coli) is one of the most relevant opportunistic pathogenic bacteria as it may cause severe morbidity and mortality in yaks (poephagus grunniens). In recent years, several kinds of antibiotics have been widely used in Tibetan areas to treat the bacterial diseases, resulting in serious repercussions on the bacterial antibiotic resistance in yaks. This investigation was conducted in order to determine the prevalence of antimicrobial resistance and integron gene cassettes in E. coli isolated from yaks in Aba Tibetan Autonomous Prefecture (Aba TAP), China. A total of 278 non-duplicated fresh samples were collected from the yaks in Aba TAP for the isolation and identification of E. coli isolates. Antimicrobial susceptibility testing is performed by using the disc diffusion method according to the Clinical and Laboratory Standards Institute guidelines (CLSI, 2013). Various antibiotic resistance genes and integron gene cassettes were detected by polymerase chain reaction (PCR) and sequencing. Overall, a total of 228 E. coli bacteria were isolated from the fresh faeces of yaks in four different geographical regions. 58% of those isolates showed multi-drug resistance capabilities (MDR) in our study. These isolated bacteria showed a high resistance rate to streptomycin (84%), cefotaxime (79%), amikacin (61%) and trimethoprim-sulfamethoxazole (54%). The most common antimicrobial resistance genes in the isolates were bla CTX-M , sul1, aph (3')-IIa, aac (3)-IIa, aac (6')-Ib, tetB, with respective detection rates of 65%, 46%, 35%, 13%, 11%, and 10%. Furthermore, 66% and 6% of the strains carried Class 1 and 2 integrons, respectively. However, the class 3 integron was not detected. Gene cassette arrays in the class 1 integron included aadA1, aadA7, aadA5, aadA17, dfrA1, dfrA5, dfrA1-aadA1, dfrA12-aadA2 and dfrA17-aadA5. The most prevalent gene cassette was aadA1 (20%). For the class 2 integron, dfrA1-sat2-aadA1 (6%) and dfrA1-sat1-aadA1 (0.4%) were also detected as part of this research. High multi-drug resistance rates have been discovered, as well as a prevalence of antibiotic resistance genes and integron gene cassettes in the E. coli isolated from the faeces of yak. This might create a potential problem for treatment of the yaks' bacterial infections as well as food hygiene for humans. It is therefore urgently necessary to begin continuous surveillance and analysis of antibiotic resistance and integron cassettes in other bacteria from yaks. Copyright © 2017 Elsevier Ltd. All rights reserved.

Isolation and characterization of Pediococcus halophilus from salted anchovies (Engraulis anchoita).

PubMed Central

Villar, M; de Ruiz Holgado, A P; Sanchez, J J; Trucco, R E; Oliver, G

1985-01-01

The presence of bacteria in salted anchovies during and at the end of the curing process was investigated. Attempts to isolate bacteria under aerobic or anaerobic conditions led to the isolation of only bacteria of the genus Pediococcus which were identified as Pediococcus halophilus. The isolates correspond to a rather heterogeneous group in which some of the members differ in some biochemical tests from the types described in the literature. PMID:3994370

Multicenter Evaluation of the Bruker MALDI Biotyper CA System for the Identification of Clinically Important Bacteria and Yeasts.

PubMed

Wilson, Deborah A; Young, Stephen; Timm, Karen; Novak-Weekley, Susan; Marlowe, Elizabeth M; Madisen, Neil; Lillie, Jennifer L; Ledeboer, Nathan A; Smith, Rebecca; Hyke, Josh; Griego-Fullbright, Christen; Jim, Patricia; Granato, Paul A; Faron, Matthew L; Cumpio, Joven; Buchan, Blake W; Procop, Gary W

2017-06-01

A report on the multicenter evaluation of the Bruker MALDI Biotyper CA System (MBT-CA; Bruker Daltonics, Billerica, MA) for the identification of clinically important bacteria and yeasts. In total, 4,399 isolates of medically important bacteria and yeasts were assessed in the MBT-CA. These included 2,262 aerobic gram-positive (AGP) bacteria, 792 aerobic gram-negative (AGN) bacteria 530 anaerobic (AnA) bacteria, and 815 yeasts (YSTs). Three processing methods were assesed. Overall, 98.4% (4,329/4,399) of all bacterial and yeast isolates were correctly identified to the genus and species/species complex level, and 95.7% of isolates were identified with a high degree of confidence. The percentage correctly identified and the percentage identified correctly with a high level of confidence, respectively, were as follows: AGP bacteria (98.6%/96.5%), AGN bacteria (98.5%/96.8%), AnA bacteria (98.5%/97.4%), and YSTs (97.8%/87.6%). The extended direct transfer method was only minimally superior to the direct transfer method for bacteria (89.9% vs 86.8%, respectively) but significantly superior for yeast isolates (74.0% vs 48.9%, respectively). The Bruker MALDI Biotyper CA System accurately identifies most clinically important bacteria and yeasts and has optional processing methods to improve isolate characterization. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Ecological aspects of microorganisms inhabiting uranium mill tailings

USGS Publications Warehouse

Miller, C.L.; Landa, E.R.; Updegraff, D.M.

1987-01-01

Numbers and types of microorganisms in uranium mill tailings were determined using culturing techniques. Arthrobacter were found to be the predominant microorganism inhabiting the sandy tailings, whereas Bacillus and fungi predominated in the slime tailings. Sulfate-reducing bacteria, capable of leaching radium, were isolated in low numbers from tailings samples but were isolated in significantly high numbers from topsoil in contact with the tailings. The results are placed in the context of the magnitude of uranium mill tailings in the United States, the hazards posed by the tailings, and how such hazards could be enhanced or diminished by microbial activities. Patterns in the composition of the microbial population are evaluated with respect to the ecological variables that influence microbial growth. ?? 1987 Springer-Verlag New York Inc.

Actinomycetes of Orthosipon stamineus rhizosphere as producer of antibacterial compound against multidrug resistant bacteria

NASA Astrophysics Data System (ADS)

Rante, H.; Yulianty, R.; Usmar; Djide, N.; Subehan; Burhamzah, R.; Prasad, M. B.

2017-11-01

The increasing case of antibiotic resistence has become an important problem to be faced in treating the infection diseases. The diversities of microbia, especially actinomycetes bacteria which originated from rizosphere soil of medicinal plant, has opened a chance for discovering the metabolites which can be used in solving the antibiotic resistant pathogenic bacteria problems. The aim of this research was to isolate the actinobacteria originated from medicinal plant rizosphere of Orthosipon stamineus as the producer of anti-multidrug resistances bacteria compounds. Three isolates of actinomycetes has been isolated from Orthosipon stamineus rhizosphere named KC3-1, KC3-2 and KC3-3. One isolate (KC3-3) showed big activity in inhibiting the test microbes by antagonistic test of actinomycetes isolates against Staphylococcus aureus and Eschericia coli antibiotic resistant bacteria. Furthermore, the KC3-3 isolate was fermented in Starch Nitrate Broth (SNB) medium for 14 days. The supernatant and the biomass of the fermentation yield were separated. The supernatant were extracted using ethyl acetate as the solvent and the biomass were extracted using methanol. The antibacterial activity test of ethyl acetate and methanol extract revealed that the extracts can inhibit the bacteria test up to 5% concentration. The ethyl acetate and methanol extracts can inhibit the bacteria test up to 5% concentration.

Evaluation of VITEK mass spectrometry (MS), a matrix-assisted laser desorption ionization time-of-flight MS system for identification of anaerobic bacteria.

PubMed

Lee, Wonmok; Kim, Myungsook; Yong, Dongeun; Jeong, Seok Hoon; Lee, Kyungwon; Chong, Yunsop

2015-01-01

By conventional methods, the identification of anaerobic bacteria is more time consuming and requires more expertise than the identification of aerobic bacteria. Although the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) systems are relatively less studied, they have been reported to be a promising method for the identification of anaerobes. We evaluated the performance of the VITEK MS in vitro diagnostic (IVD; 1.1 database; bioMérieux, France) in the identification of anaerobes. We used 274 anaerobic bacteria isolated from various clinical specimens. The results for the identification of the bacteria by VITEK MS were compared to those obtained by phenotypic methods and 16S rRNA gene sequencing. Among the 249 isolates included in the IVD database, the VITEK MS correctly identified 209 (83.9%) isolates to the species level and an additional 18 (7.2%) at the genus level. In particular, the VITEK MS correctly identified clinically relevant and frequently isolated anaerobic bacteria to the species level. The remaining 22 isolates (8.8%) were either not identified or misidentified. The VITEK MS could not identify the 25 isolates absent from the IVD database to the species level. The VITEK MS showed reliable identifications for clinically relevant anaerobic bacteria.

Isolation and in vitro evaluation of bacteriophages against MDR-bacterial isolates from septic wound infections.

PubMed

Pallavali, Roja Rani; Degati, Vijaya Lakshmi; Lomada, Dakshayani; Reddy, Madhava C; Durbaka, Vijaya Raghava Prasad

2017-01-01

Multi-drug resistance has become a major problem for the treatment of pathogenic bacterial infections. The use of bacteriophages is an attractive approach to overcome the problem of drug resistance in several pathogens that cause fatal diseases. Our study aimed to isolate multi drug resistant bacteria from patients with septic wounds and then isolate and apply bacteriophages in vitro as alternative therapeutic agents. Pus samples were aseptically collected from Rajiv Gandhi Institute of Medical Science (RIMS), Kadapa, A.P., and samples were analyzed by gram staining, evaluating morphological characteristics, and biochemical methods. MDR-bacterial strains were collected using the Kirby-Bauer disk diffusion method against a variety of antibiotics. Bacteriophages were collected and tested in vitro for lytic activity against MDR-bacterial isolates. Analysis of the pus swab samples revealed that the most of the isolates detected had Pseudomonas aeruginosa as the predominant bacterium, followed by Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. Our results suggested that gram-negative bacteria were more predominant than gram-positive bacteria in septic wounds; most of these isolates were resistant to ampicillin, amoxicillin, penicillin, vancomycin and tetracycline. All the gram-positive isolates (100%) were multi-drug resistant, whereas 86% of the gram-negative isolates had a drug resistant nature. Further bacteriophages isolated from sewage demonstrated perfect lytic activity against the multi-drug resistant bacteria causing septic wounds. In vitro analysis of the isolated bacteriophages demonstrated perfect lysis against the corresponding MDR-bacteria, and these isolated phages may be promising as a first choice for prophylaxis against wound sepsis, Moreover, phage therapy does not enhance multi-drug resistance in bacteria and could work simultaneously on a wide variety of MDR-bacteria when used in a bacteriophage cocktail. Hence, our results suggest that these bacteriophages could be potential therapeutic options for treating septic wounds caused by P. aeruginosa, S. aureus, K. pneumoniae and E. coli.

Thermostable 𝜶-Amylase Activity from Thermophilic Bacteria Isolated from Bora Hot Spring, Central Sulawesi

NASA Astrophysics Data System (ADS)

Gazali, F. M.; Suwastika, I. N.

2018-03-01

α-Amylase is one of the most important enzyme in biotechnology field, especially in industrial application. Thermostability of α-Amylase produced by thermophilic bacteria improves industrial process of starch degradation in starch industry. The present study were concerned to the characterization of α-Amylase activity from indigenous thermophilic bacteria isolated from Bora hot spring, Central Sulawesi. There were 18 isolates which had successfully isolated from 90°C sediment samples of Bora hot spring and 13 of them showed amylolytic activity. The α-Amylase activity was measured qualitatively at starch agar and quantitatively based on DNS (3,5-Dinitrosalicylic acid) methods, using maltose as standard solution. Two isolates (out of 13 amylolytic bacteria), BR 002 and BR 015 showed amylolytic index of 0.8 mm and 0.5 mm respectively, after being incubated at 55°C in the 0.002% Starch Agar Medium. The α-Amylase activity was further characterized quantitatively which includes the optimum condition of pH and temperature of α-Amylase crude enzyme from each isolate. To our knowledge, this is the first report on isolation and characterization of a thermostable α-Amylase from thermophilic bacteria isolated from Central Sulawesi particularly from Bora hot spring.

Isolation of diverse members of the Aquificales from geothermal springs in Tengchong, China

PubMed Central

Hedlund, Brian P.; Reysenbach, Anna-Louise; Huang, Liuquin; Ong, John C.; Liu, Zizhang; Dodsworth, Jeremy A.; Ahmed, Reham; Williams, Amanda J.; Briggs, Brandon R.; Liu, Yitai; Hou, Weiguo; Dong, Hailiang

2015-01-01

The order Aquificales (phylum Aquificae) consists of thermophilic and hyperthermophilic bacteria that are prominent in many geothermal systems, including those in Tengchong, Yunnan Province, China. However, Aquificales have not previously been isolated from Tengchong. We isolated five strains of Aquificales from diverse springs (temperature 45.2–83.3°C and pH 2.6–9.1) in the Rehai Geothermal Field from sites in which Aquificales were abundant. Phylogenetic analysis showed that four of the strains belong to the genera Hydrogenobacter, Hydrogenobaculum, and Sulfurihydrogenibium, including strains distant enough to likely justify new species of Hydrogenobacter and Hydrogenobaculum. The additional strain may represent a new genus in the Hydrogenothermaceae. All strains were capable of aerobic respiration under microaerophilic conditions; however, they had variable capacity for chemolithotrophic oxidation of hydrogen and sulfur compounds and nitrate reduction. PMID:25774153

The First Report of Drug Resistant Bacteria Isolated from the Brown-Banded Cockroach, Supella longipalpa, in Ahvaz, South-western Iran

PubMed Central

Vazirianzadeh, Babak; Dehghani, Rouhullah; Mehdinejad, Manijeh; Sharififard, Mona; Nasirabadi, Nersi

2014-01-01

Background The brown-banded cockroach, Supella longipalpa is known as a carrier of pathogenic bacteria in urban environments, but its role is not well documented regarding the carriage of antibiotic-resistant pathogenic bacteria in Iran. The aim of this study was to determine the resistance bacteria isolated from the brown-banded cockroach in Ahvaz, south west of Iran. Methods: Totally 39 cockroaches were collected from kitchen area of houses and identified. All specimens were cultured to isolate the bacterial agents on blood agar and MacConky agar media. The microorganisms were identified using necessary differential and biochemical tests. Antimicrobial susceptibility tests were performed for isolated organisms by Kirby-Bauer’s disk diffusion according to NCLI guideline, using 18 antibiotics. Results: From the 39 collected S. langipalpa, 179 bacterial agents were isolated, 92 of alimentary ducts and 87 of external body surfaces. Isolated bacteria from cockroaches were identified as Enterobacter spp., Klebsiella spp., Citrobacter spp., Escherichia coli, Salmonella spp., Proteus spp., coagulase negative staphylococci, Serratia marcescens, Staphylococcus aureus, and Bacillus species. The pattern resistance rates were determined for gram negative bacilli and gram positive cocci regarding 18 antibiotics. Conclusion: The brown-banded cockroach can be involved in the spread of drug resistant bacteria and increases the possibility of contacting human environment to drug resistant bacteria. Therefore, the potential of removing this insect should be improved. This is the first original report of drug resistant bacteria isolated from the brown-banded cockroach of Iran. PMID:25629065

Burkholderia puraquae sp. nov., a novel species of the Burkholderia cepacia complex isolated from hospital settings and agricultural soils.

PubMed

Martina, Pablo; Leguizamon, Mariana; Prieto, Claudia I; Sousa, Silvia A; Montanaro, Patricia; Draghi, Walter O; Stämmler, Maren; Bettiol, Marisa; de Carvalho, Carla C C R; Palau, Juliana; Figoli, Cecilia; Alvarez, Florencia; Benetti, Silvina; Lejona, Sergio; Vescina, Cecilia; Ferreras, Julián; Lasch, Peter; Lagares, Antonio; Zorreguieta, Angeles; Leitão, Jorge H; Yantorno, Osvaldo M; Bosch, Alejandra

2018-01-01

Bacteria from the Burkholderia cepacia complex (Bcc) are capable of causing severe infections in patients with cystic fibrosis (CF). These opportunistic pathogens are also widely distributed in natural and man-made environments. After a 12-year epidemiological surveillance involving Bcc bacteria from respiratory secretions of Argentinean patients with CF and from hospital settings, we found six isolates of the Bcc with a concatenated species-specific allele sequence that differed by more than 3 % from those of the Bcc with validly published names. According to the multilocus sequence analysis (MLSA), these isolates clustered with the agricultural soil strain, Burkholderia sp. PBP 78, which was already deposited in the PubMLST database. The isolates were examined using a polyphasic approach, which included 16S rRNA, recA, Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), DNA base composition, average nucleotide identities (ANIs), fatty acid profiles, and biochemical characterizations. The results of the present study demonstrate that the seven isolates represent a single novel species within the Bcc, for which the name Burkholderia puraquae sp. nov. is proposed. Burkholderia puraquae sp. nov. CAMPA 1040 T (=LMG 29660 T =DSM 103137 T ) was designated the type strain of the novel species, which can be differentiated from other species of the Bcc mainly from recA gene sequence analysis, MLSA, ANIb, MALDI-TOF MS analysis, and some biochemical tests, including the ability to grow at 42 °C, aesculin hydrolysis, and lysine decarboxylase and β-galactosidase activities.

Isolation, Characterisation and Antagonistic Activity of Bacteria Symbionts Hardcoral Pavona sp. Isolated from Panjang Island, Jepara Against Infectious Multi-drug Resistant (MDR) Bacteria

NASA Astrophysics Data System (ADS)

Ayuningrum, D.; Kristiana, R.; Asagabaldan, M. A.; Sabdono, A.; Radjasa, O. K.; Nuryadi, H.; Trianto, A.

2017-02-01

Pavona sp. is highly spread over Indonesian waters including Panjang Island. Several studies showed that bacteria symbionts hardcoral were the big source of antibiotic product, but there was limited research of the bacteria symbionts with hardcoral Pavona sp. In this research bacteria symbionts from hardcoral Pavona sp. had been collected from Panjang Island, Jepara. Marine bacteria symbionts were isolated by serial dillution method, while antibacterial activity was performed by using overlay and agar block method. The total of 2 from 5 isolates were active to MDR bacteria such as Enterobacter aerogenes and Acinetobacter baumanii, the code were PHC 44/04 and PHC 44/05. Then both of them were identified by morphological and molecular DNA characterization using 16 S rRNA gene sequence. The result of 16 S rRNA identification shows PHC 44/04 has 99% similarities with Virgibacillus salarius strain sa-Vb 1, while PHC 44/05 shows 99% similarities with Pseudoalteromonas flavipulchra strain NCIMB 2033.

Stenotrophomonas maltophilia is highly prevalent among houseflies (Musca domestica).

PubMed

Fukuda, Akira; Usui, Masaru; Wakao, Hideyuki; Boonla, Chanchai; Tamura, Yutaka

2017-08-04

Stenotrophomonas maltophilia is capable of surviving in a wide variety of environments and is considered to be among the antimicrobial-resistant bacteria of greatest public health concern in hospital settings. To clarify the role of houseflies (Musca domestica) in disseminating this bacterium, we collected 99 individuals from 15 locations (9 farms and 6 urban areas) in Thailand. S. maltophilia was isolated from 39 % (39/99) of these houseflies, with the isolation rates being similar in farms and urban areas. Multiple-antimicrobial resistance was evident among the S. maltophilia isolates obtained. Of note, the rate of resistance to trimethoprim/sulfamethoxazole (TMP/SMX), the recommended first-line antimicrobial for S. maltophilia infection, was relatively high (30 %). Almost all of the isolates had a different PFGE pattern. These results suggest that houseflies ingest and host S. maltophilia from several different environmental sources. In conclusion, houseflies may facilitate the spread of antimicrobial-resistant (including TMP/SMX-resistant) S. maltophilia from environmental sources to humans.

Aeromonas veronii, a tributyltin (TBT)-degrading bacterium isolated from an estuarine environment, Ria de Aveiro in Portugal.

PubMed

Cruz, Andreia; Caetano, Tânia; Suzuki, Satoru; Mendo, Sónia

2007-12-01

Organotin compounds are used in a variety of industrial processes therefore their subsequent discharge into the environment is widespread. Bacteria play an important role in biogeochemical transformations acting as natural decontamination agents. Therefore, screening for tributyltin (TBT)-resistant and -degrading bacteria is relevant for the selection of isolates with decontamination ability of these polluted areas. With this purpose, 50 strains were isolated from sediment and water from Ria de Aveiro and their tolerance to TBT, up to 3mM, was evaluated. Generally, occurrence of highly TBT-resistant bacteria was observed, and Gram negative bacteria exhibited more tolerance to TBT than Gram positive bacteria. A memory response was observed when bacteria were progressively exposed to increasingly higher TBT concentrations. One isolate, Aeromonas veronii Av27, highly resistant to TBT (3mM) uses this compound as carbon source and degrades it to less toxic compounds.

[Biodiversity of phosphate-dissolving and plant growth--promoting endophytic bacteria of two crops].

PubMed

Huang, Jing; Sheng, Xiafang; He, Linyan

2010-06-01

We isolated and characterized phosphate-dissolving endophytic bacteria from two commonly cultivated crops. Phosphate-dissolving endophytic bacteria were isolated by plating and screening from interior tissues of rape and maize plants on NBRIP medium with tricalcium phosphate as sole phosphate source. Bacteria were characterized regarding characteristics that may be relevant for a beneficial plant-microbe interaction-indoleacetic acid, siderophore and 1-aminocyclopropane-1-carboxylic acid deaminase production,and further classified by restriction analysis of 16S rDNA. Eleven typical strains were identified by 16S rDNA sequence analysis. Thirty-two phosphate-dissolving endophytic bacteria were isolated from maize and rape plants and classified by restriction analysis of 16S rDNA in 8 different taxonomic groups at the similarity level of 76%. All the isolates could release phosphate from tricalcium phosphate and decrease the pH of the medium. The maximum phosphate content (537.6 mg/L) in the solution was obtained with strain M1L5. Thirteen isolates isolated from rape produced indoleacetic acid and siderophore, 68.4% and 63.2% of the strains isolated from maize produced indoleacetic acid and siderophore,respectively. 63.2% of the strains isolated from maize were able to grow on 1-aminocyclopropane-1-carboxylic acid as the sole nitrogen source. The eleven strains belonged to five different genera including Pantoea, Pseudomonas, Burkholderia, Acinetobacter and Ralstonia. Phosphate-dissolving endophytic bacteria isolated from rape and maize plants have abundant characteristics relative to promoting plant growth and genetic diversity.

Enrichment and isolation of crude oil degrading bacteria from some mussels collected from the Persian Gulf.

PubMed

Bayat, Zeynab; Hassanshahian, Mehdi; Hesni, Majid Askari

2015-12-15

To date, little is known about existing relationships between mussels and bacteria in hydrocarbon-contaminated marine environments. The aim of this study is to find crude oil degrading bacteria in some mussels at the Persian Gulf. Twenty eight crude oil degrading bacteria were isolated from three mussels species collected from oil contaminated area at Persian Gulf. According to high growth and degradation of crude oil four strains were selected between 28 isolated strains for more study. Determination the nucleotide sequence of the gene encoding for 16S rRNA show that these isolated strains belong to: Shewanella algae isolate BHA1, Micrococcus luteus isolate BHA7, Pseudoalteromonas sp. isolate BHA8 and Shewanella haliotis isolate BHA35. The residual crude oil in culture medium was analysis by Gas Chromatography (GC). The results confirmed that these strains can degrade: 47.24%, 66.08%, 27.13% and 69.17% of crude oil respectively. These strains had high emulsification activity and biosurfactant production. Also, the effects of some factors on crude oil degradation by isolated strains were studied. The results show that the optimum concentration of crude oil was 2.5% and the best degradation take place at 12% of salinity. This research is the first reports on characterization of crude oil degrading bacteria from mussels at Persian Gulf and by using of these bacteria in the field the effect of oil pollution can be reduce on this marine environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Selection and screening of microbial consortia for efficient and ecofriendly degradation of plastic garbage collected from urban and rural areas of Bangalore, India.

PubMed

Skariyachan, Sinosh; Megha, M; Kini, Meghna Niranjan; Mukund, Kamath Manali; Rizvi, Alya; Vasist, Kiran

2015-01-01

Industrialization and urbanization have led to massive accumulation of plastic garbage all over India. The persistence of plastic in soil and aquatic environment has become ecological threat to the metropolitan city such as Bangalore, India. Present study investigates an ecofriendly, efficient and cost-effective approach for plastic waste management by the screening of novel microbial consortia which are capable of degrading plastic polymers. Plastic-contaminated soil and water samples were collected from six hot spots of urban and rural areas of Bangalore. The plastic-degrading bacteria were enriched, and degradation ability was determined by zone of clearance method. The percentage of polymer degradation was initially monitored by weight loss method, and the main isolates were characterized by standard microbiology protocols. These isolates were used to form microbial consortia, and the degradation efficiency of the consortia was compared with individual isolate and known strains obtained from the Microbial Type Culture Collection (MTCC) and Gene Bank, India. One of the main enzymes responsible for polymer degradation was identified, and the biodegradation mechanism was hypothesized by bioinformatics studies. From this study, it is evident that the bacteria utilized the plastic polymer as a sole source of carbon and showed 20-50% weight reduction over a period of 120 days. The two main bacteria responsible for the degradation were microbiologically characterized to be Pseudomonas spp. These bacteria could grow optimally at 37 °C in pH 9.0 and showed 35-40% of plastic weight reduction over 120 days. These isolates were showed better degradation ability than known strains from MTCC. The current study further revealed that the microbial consortia formulated by combining Psuedomonas spp. showed 40 plastic weight reduction over a period of 90 days. Further, extracellular lipase, one of the main enzymes responsible for polymer degradation, was identified. The computational docking studies suggested that polyethylene glycol and polystyrene present in the plastics might have good interaction towards the microbial lipase with stable binding and interacting forces which probably could be one of the reasons for the degradative mechanisms.

Isolation and identification of amylase-producing, endospore-forming bacteria from the alimentary tract of commercially processed broilers

USDA-ARS?s Scientific Manuscript database

Bacterial cultures of crop and cecal contents of adult poultry contain beneficial bacteria that reduce colonization of young poultry by Salmonella. Since endospore-forming bacteria may play a role in competitive exclusion of Salmonella in poultry, 3 trials were conducted to isolate these bacteria fr...

Isolation and identification of cellulolytic bacteria from termites gut (Cryptotermes sp.)

NASA Astrophysics Data System (ADS)

Peristiwati; Natamihardja, Y. S.; Herlini, H.

2018-05-01

The energy and environmental crises developed due to a huge amount of cellulosic materials are disposed of as “waste.” Cellulose is the most abundant biopolymer on Earth. The hydrolysis of cellulose to glucose and soluble sugars has thus become a subject of intense research. Termites are one of the most important soil insects that efficiently decompose lignocelluloses with the aid of their associated microbial symbionts to a simpler form of sugars. The steps of this study consisted of cellulose isolation, cellulolytic bacteria isolation and identification. Cellulose degrading bacteria from termite (Cryptotermes sp.) gut flora were isolated, screened and their identification was studied which showed halo zones due to CMC agar. Among 12 isolates of bacteria, six isolates were cellulolytic. MLC-A isolate had shown a maximum in a cellulolytic index (1.32). Each isolate was identified based on standard physical and biochemical tests. Three isolates were identified in the genus of Clostridium, one isolate be placed in the group of Mycobacteriaceae, Lactobacillaceae or Coryneform and the last one in the genus Proteus.

Protein Oxidation: Key to Bacterial Desiccation Resistance?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fredrickson, Jim K.; Li, Shu-Mei W.; Gaidamakova, E.

For extremely ionizing radiation resistant bacteria, survival has been attributed to protection of proteins from oxidative damage during irradiation, with the result that repair systems survive and function with far greater efficiency during recovery than in sensitive bacteria. Here we examined the relationship between survival of dry-climate soil bacteria and the level of cellular protein oxidation induced by desiccation. Bacteria were isolated from surface soils of the shrub-steppe of the U.S. Department of Energy’s Hanford Site in Washington state. A total of 63 isolates were used for phylogenetic analysis. The majority of isolates were closely related to members of themore » genus Deinococcus, with Chelatococcus, Methylobacterium and Bosea also among the genera identified. Desiccation-resistant isolates accumulated high intracellular manganese and low iron concentrations compared to sensitive bacteria. In vivo, proteins of desiccation-resistant bacteria were protected from oxidative modifications that introduce carbonyl groups in sensitive bacteria during drying. We present the case that survival of bacteria that inhabit dry-climate soils are highly dependent on mechanisms which limit protein oxidation during dehydration.« less

Antimicrobial susceptibility of starter culture bacteria used in Norwegian dairy products.

PubMed

Katla, A K; Kruse, H; Johnsen, G; Herikstad, H

2001-07-20

Commercial starter culture bacteria are widely used in the production of dairy products and could represent a potential source for spread of genes encoding resistance to antimicrobial agents. To learn more about the antimicrobial susceptibility of starter culture bacteria used in Norwegian dairy products, a total of 189 isolates of lactic acid bacteria were examined for susceptibility to ampicillin, penicillin G, cephalothin, vancomycin, bacitracin, gentamicin, streptomycin, erythromycin, tetracycline, chloramphenicol, quinupristin/dalfopristin, ciprofloxacin, trimethoprim and sulphadiazine using Etest for MIC determination. Most of the isolates (140) originated from 39 dairy products (yoghurt, sour cream, fermented milk and cheese), while 49 were isolated directly from nine commercial cultures. The bacteria belonged to the genera Lactobacillus, Lactococcus, Leuconostoc and Streptococcus. Only one of the 189 isolates was classified as resistant to an antimicrobial agent included in the study. This isolate, a lactobacillus, was classified as high level resistant to streptomycin. The remaining isolates were not classified as resistant to the antimicrobial agents included other than to those they are known to have a natural reduced susceptibility to. Thus, starter culture bacteria in Norwegian dairy products do not seem to represent a source for spread of genes encoding resistance to antimicrobial agents.

Isolation, morphological identification and in vitro antibacterial activity of endophytic bacteria isolated from Azadirachta indica (neem) leaves

PubMed Central

Singh, Ankit Kumar; Sharma, Rajesh Kumar; Sharma, Varsha; Singh, Tanmay; Kumar, Rajesh; Kumari, Dimple

2017-01-01

Aim: The objective of this study was to isolate endophytic bacteria from Azadirachta indica (neem) leaves, their identification and investigate their antibacterial activity against three Gram-positive bacteria, Staphylococcus aureus, Streptococcus pyogenes and Bacillus cereus and Gram-negative bacteria Escherichia coli, Salmonella Typhimurium and Klebsiella pneumoniae. Materials and Methods: Fresh leaves of A. indica (neem) was procured from the Department of Botany, JNKVV, Jabalpur. Five samples were taken, and each sample was divided into five subsamples and separated for further isolation of endophytic bacteria. For sterilization leaves were treated with double distilled water, 0.1% sodium hypochlorite, 0.01% bavistin, 0.05% and 70% ethanol. Sterilized leaves of the plants were embedded in Kings B (KB) petri plates and incubated at 37°C for 24 h. Characterization of the bacteria was done according to its morphology and by Gram-staining. After that, a single colony was transferred into brain heart infusion (BHI) broth and incubated at 37°C for 24 h. The antibacterial effect was studied by the disk diffusion method with known antibiotic ciprofloxacin (Ci) as standard. Results: A total of 25 bacterial isolates from A. indica (neem) were obtained and identified morphologically. Most of the samples on KB media depicted irregular shape, flat elevation, undulated, rough, opaque, and white in color. Most of the samples on blood agar showed irregular, raise elevation, undulated, smooth, opaque and all the isolates were nonhemolytic and nonchromogenic. The growth of endophytic bacteria in BHI broth were all isolates showed turbidity. The microscopic examination revealed that maximum isolates were Gram-positive and rod shaped. Good antibacterial activity was observed against S. aureus, Streptococcus pyogenes, E. coli, Salmonella Typhimurium, and K. pneumoniae. Conclusions: Endophytic bacteria are present in leaves of A. indica (neem) and it possesses antibacterial activity against few Gram-positive and Gram-negative bacteria. PMID:28620254

Adhesion properties of potentially probiotic Lactobacillus kefiri to gastrointestinal mucus.

PubMed

Carasi, Paula; Ambrosis, Nicolás M; De Antoni, Graciela L; Bressollier, Philippe; Urdaci, María C; Serradell, María de los Angeles

2014-02-01

We investigated the mucus-binding properties of aggregating and non-aggregating potentially probiotic strains of kefir-isolated Lactobacillus kefiri, using different substrates. All the strains were able to adhere to commercial gastric mucin (MUCIN) and extracted mucus from small intestine (SIM) and colon (CM). The extraction of surface proteins from bacteria using LiCl or NaOH significantly reduced the adhesion of three selected strains (CIDCA 8348, CIDCA 83115 and JCM 5818); although a significant proportion (up to 50%) of S-layer proteins were not completely eliminated after treatments. The surface (S-layer) protein extracts from all the strains of Lb. kefiri were capable of binding to MUCIN, SIM or CM, and no differences were observed among them. The addition of their own surface protein extract increased adhesion of CIDCA 8348 and 83115 to MUCIN and SIM, meanwhile no changes in adhesion were observed for JCM 5818. None of the seven sugars tested had the ability to inhibit the adhesion of whole bacteria to the three mucus extracts. Noteworthy, the degree of bacterial adhesion reached in the presence of their own surface protein (S-layer) extract decreased to basal levels in the presence of some sugars, suggesting an interaction between the added sugar and the surface proteins. In conclusion, the ability of these food-isolated bacteria to adhere to gastrointestinal mucus becomes an essential issue regarding the biotechnological potentiality of Lb. kefiri for the food industry.

Microbial skin flora of selected cancer patients and hospital personnel.

PubMed Central

McBride, M E; Duncan, W C; Bodey, G P; McBride, C M

1976-01-01

The bacterial flora of the skin from five anatomical sites on 10 leukemia patients, 10 patients with malignant melanoma, and a control group of 10 medical personnel was examined quantitatively and qualitatively. This was done to determine whether malignant disease results in changes in skin flora and to establish carrier rates of gram-negative bacteria on the skin of personnel in hospital environments. Gram-negative bacteria were isolated more frequently (74 isolates from 100 cultures) from the skin of leukemia patients than from either patients with malignant melanoma (8 isolates from 100 cultures) or the medical personnel (9 isolates from 100 cultures). Klebsiella pneumoniae and Pseudomonas aeruginosa were isolated exclusively from leukemia patients. Relative proportions of gram-negative bacteria in total populations were determined. The axilla was the only site with a uniformly high proportion of gram-negative bacteria. From all other sites cultured, gram-negative populations were low (1 to 5 bacteria/cm2 of skin), although a high proportion of gram-negative populations occurred randomly throughout all subject groups. It was concluded that leukemia patients tend to carry gram-negative bacteria on the skin. The factors permitting colonization of skin by gram-negative bacteria are discussed. PMID:943418

Identification and Antibacterial Activity of Bacteria Isolated from Marine Sponge Haliclona (Reniera) sp. against Multi-Drug Resistant Human Pathogen

NASA Astrophysics Data System (ADS)

Ardhanu Asagabaldan, Meezan; Ayuningrum, D.; Kristiana, R.; Sabdono, A.; Radjasa, O. K.; Trianto, A.

2017-02-01

The marine sponge Haliclona (Reniera) sp. was a potential source of natural bioactive compounds. This sponge widely distributed along the coast of Panjang Island, Jepara, Indonesia. The aims of this research were to isolate the associated bacteria with Haliclona (Reniera) sp. and to screen the antibacterial activity against Multi-Drug Resistant (MDR) bacteria. Amount five bacteria were isolated using media selective for bacteria. The antibacterial activities of bacteria were performed by overlay methods. The bacteria strain PSP. 39-04 had the best activity against Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter baumannii, and Enterobacter cloaceae. Based on colony morphology and phylogenetic characterization using 16S rRNA gene sequencing, PSP 39-04 was closely related with Chromohalobacter salixigens strain DSM3043.

Plant growth-promoting potential of bacteria isolated from active volcano sites of Barren Island, India.

PubMed

Amaresan, N; Kumar, K; Sureshbabu, K; Madhuri, K

2014-02-01

To elucidate the biodiversity of plant growth-promoting (PGP) bacteria in active volcano sites of Barren Island, India, a total of 102 bacteria were isolated and screened for their multifunctional PGP properties. The results revealed that 21 isolates (20.6%) survived heat shock at 72°C and 11 (10.8%) isolates were able to grow exposed to 25% NaCl (w/v). In assaying for PGP properties, 59 (57.8%) isolates shown indole acetic acid (IAA) like substances production, 57 isolates (55.9%) produced siderophore and 34 (33.3%) solubilized inorganic phosphate qualitatively. Whereas in the production of extracellular enzymes, 42 isolates (41.2%) produced protease and amylase, 26 (25.5%) isolates produced lipase and 24 (23.5%) isolates produced cellulase. In antagonistic activity, 30 isolates (29.4%) were found antagonistic against Macrophomina sp., 20 isolates (19.6%) against Rhizoctonia solani and 15 isolates (14.7%) against Sclerotium rolfsii. The results based on 16 rRNA gene sequencing revealed that the PGP bacteria belonged to 22 different species comprising 13 genera. Based on multifunctional properties, nine isolates were further selected to determine the PGP in brinjal and chilli seeds. Of the bacteria tested, the isolate BAN87 showed increased root and shoot length of both the crops followed in plant growth promotion by BAN86 and BAN43. The outcome of this research proves plausible practical applicability of these PGPB for crop production in soils of saline and arid environments. The present research shows diverse plant growth-promoting (PGP) bacteria could be isolated from the active volcano site and suggests that volcano sites represent an ecological niche, which harbours a diverse and hitherto largely uncharacterized microbial population with yet unknown and untapped potential biotechnological applications, for example, plant growth promoters, as evidenced from this study. The outcome of this research may have a practical effect on crop production methodologies in saline and arid environment soils. © 2013 The Society for Applied Microbiology.

Bacillus arsenicoselenatis, sp. nov., and Bacillus selenitireducens, sp. nov.: Two haloalkaliphiles from Mono Lake, California that respire oxyanions of selenium and arsenic

USGS Publications Warehouse

Switzer, Blum J.; Burns, Bindi A.; Buzzelli, J.; Stolz, J.F.; Oremland, R.S.

1998-01-01

Two gram-positive anaerobic bacteria (strains E1H and MLS10) were isolated from the anoxic muds of Mono Lake, California, an alkaline, hypersaline, arsenic-rich water body. Both grew by dissimilatory reduction of As(V) to As(III) with the concomitant oxidation of lactate to acetate plus CO2. Bacillus arsenicoselenatis (strain E1H) is a spore-forming rod that also grew by dissimilatory reduction of Se(VI) to Se(IV). Bacillus selenitireducens (strain MLS 10) is a short, non-spore-forming rod that grew by dissimilatory reduction of Se(IV) to Se(0). When the two isolates were cocultured, a complete reduction of Se(VI) to Se(0) was achieved. Both isolates are alkaliphiles and had optimal specific growth rates in the pH range of 8.5-10. Strain E1H had a salinity optimum at 60 g 1-1 NaCl, while strain MLS10 had optimal growth at lower salinities (24-60 g 1-1 NaCl). Both strains have limited abilities to grow with electron donors and acceptors other than those given above. Strain MLS10 demonstrated weak growth as a microaerophile and was also capable of fermentative growth on glucose, while strain E1H is a strict anaerobe. Comparative 16S rRNA gene sequence analysis placed the two isolates with other Bacillus spp. in the low G+C gram-positive group of bacteria.

NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

PubMed Central

Burse, Antje; Weingart, Helge; Ullrich, Matthias S.

2004-01-01

Blossoms are important sites of infection for Erwinia amylovora, the causal agent of fire blight of rosaceous plants. Before entering the tissue, the pathogen colonizes the stigmatic surface and has to compete for space and nutrient resources within the epiphytic community. Several epiphytes are capable of synthesizing antibiotics with which they antagonize phytopathogenic bacteria. Here, we report that a multidrug efflux transporter, designated NorM, of E. amylovora confers tolerance to the toxin(s) produced by epiphytic bacteria cocolonizing plant blossoms. According to sequence comparisons, the single-component efflux pump NorM is a member of the multidrug and toxic compound extrusion protein family. The corresponding gene is widely distributed among E. amylovora strains and related plant-associated bacteria. NorM mediated resistance to the hydrophobic cationic compounds norfloxacin, ethidium bromide, and berberine. A norM mutant was constructed and exhibited full virulence on apple rootstock MM 106. However, it was susceptible to antibiotics produced by epiphytes isolated from apple and quince blossoms. The epiphytes were identified as Pantoea agglomerans by 16S rRNA analysis and were isolated from one-third of all trees examined. The promoter activity of norM was twofold greater at 18°C than at 28°C. The lower temperature seems to be beneficial for host infection because of the availability of moisture necessary for movement of the pathogen to the infection sites. Thus, E. amylovora might employ NorM for successful competition with other epiphytic microbes to reach high population densities, particularly at a lower temperature. PMID:14766544

The prospects of cellulase-producing bacteria for the bioconversion of lignocellulosic biomass.

PubMed

Maki, Miranda; Leung, Kam Tin; Qin, Wensheng

2009-07-29

Lignocellulosic biomass is a renewable and abundant resource with great potential for bioconversion to value-added bioproducts. However, the biorefining process remains economically unfeasible due to a lack of biocatalysts that can overcome costly hurdles such as cooling from high temperature, pumping of oxygen/stirring, and, neutralization from acidic or basic pH. The extreme environmental resistance of bacteria permits screening and isolation of novel cellulases to help overcome these challenges. Rapid, efficient cellulase screening techniques, using cellulase assays and metagenomic libraries, are a must. Rare cellulases with activities on soluble and crystalline cellulose have been isolated from strains of Paenibacillus and Bacillus and shown to have high thermostability and/or activity over a wide pH spectrum. While novel cellulases from strains like Cellulomonas flavigena and Terendinibacter turnerae, produce multifunctional cellulases with broader substrate utilization. These enzymes offer a framework for enhancement of cellulases including: specific activity, thermalstability, or end-product inhibition. In addition, anaerobic bacteria like the clostridia offer potential due to species capable of producing compound multienzyme complexes called cellulosomes. Cellulosomes provide synergy and close proximity of enzymes to substrate, increasing activity towards crystalline cellulose. This has lead to the construction of designer cellulosomes enhanced for specific substrate activity. Furthermore, cellulosome-producing Clostridium thermocellum and its ability to ferment sugars to ethanol; its amenability to co-culture and, recent advances in genetic engineering, offer a promising future in biofuels. The exploitation of bacteria in the search for improved enzymes or strategies provides a means to upgrade feasibility for lignocellulosic biomass conversion, ultimately providing means to a 'greener' technology.

The prospects of cellulase-producing bacteria for the bioconversion of lignocellulosic biomass

PubMed Central

Maki, Miranda; Leung, Kam Tin; Qin, Wensheng

2009-01-01

Lignocellulosic biomass is a renewable and abundant resource with great potential for bioconversion to value-added bioproducts. However, the biorefining process remains economically unfeasible due to a lack of biocatalysts that can overcome costly hurdles such as cooling from high temperature, pumping of oxygen/stirring, and, neutralization from acidic or basic pH. The extreme environmental resistance of bacteria permits screening and isolation of novel cellulases to help overcome these challenges. Rapid, efficient cellulase screening techniques, using cellulase assays and metagenomic libraries, are a must. Rare cellulases with activities on soluble and crystalline cellulose have been isolated from strains of Paenibacillus and Bacillus and shown to have high thermostability and/or activity over a wide pH spectrum. While novel cellulases from strains like Cellulomonas flavigena and Terendinibacter turnerae, produce multifunctional cellulases with broader substrate utilization. These enzymes offer a framework for enhancement of cellulases including: specific activity, thermalstability, or end-product inhibition. In addition, anaerobic bacteria like the clostridia offer potential due to species capable of producing compound multienzyme complexes called cellulosomes. Cellulosomes provide synergy and close proximity of enzymes to substrate, increasing activity towards crystalline cellulose. This has lead to the construction of designer cellulosomes enhanced for specific substrate activity. Furthermore, cellulosome-producing Clostridium thermocellum and its ability to ferment sugars to ethanol; its amenability to co-culture and, recent advances in genetic engineering, offer a promising future in biofuels. The exploitation of bacteria in the search for improved enzymes or strategies provides a means to upgrade feasibility for lignocellulosic biomass conversion, ultimately providing means to a 'greener' technology. PMID:19680472

Biolog(TM) ID as compared to 16S ribosomal RNA ID for environmental isolates from the deep subsurface

DOE Office of Scientific and Technical Information (OSTI.GOV)

McKinsey, P.C.

2000-05-05

The U.S. Dept of Energy (DOE) Subsurface Microbial Culture Collection (SMCC) contains nearly 10,000 strains of microorganisms isolated from terrestrial subsurface environments. Many of the aerobic, gram-negative, chemoheterotrophs isolated from the DOE Savannah River Site (SRS) have previously been identified by phylogenetic analysis of 16S ribosomal RNA (rRNA) gene nucleotide sequences. These SMCC isolates are currently being examined using Biolog GN Microplates and the Biolog Microstation System in order to gain knowledge of their metabolic capabilities and to compare Biolog IDs with 16S IDs. To accommodate the particular needs of these subsurface isolates, which are often incapable of growing undermore » high-nutrient conditions, Biolog's recommendations for inoculating isolates into Biolog GN Microplates have been altered. The isolates are grown on low nutrient media, sodium thioglycolate (3mM) is added to the culture media to inhibit capsule formation, and a low density of bacteria is inoculated into the microplate. Using these altered inoculation criteria, 60 percent of these SMCC isolates have a Biolog genus ID that matches the 16S rRNA ID. These results indicate that the Biolog System can be a good means of identifying unusual environmental isolates, even when recommended inoculation procedures are altered to accommodate particular isolate needs.« less

Bacteria isolated from bats inhibit the growth of Pseudogymnoascus destructans, the causative agent of white-nose syndrome.

PubMed

Hoyt, Joseph R; Cheng, Tina L; Langwig, Kate E; Hee, Mallory M; Frick, Winifred F; Kilpatrick, A Marm

2015-01-01

Emerging infectious diseases are a key threat to wildlife. Several fungal skin pathogens have recently emerged and caused widespread mortality in several vertebrate groups, including amphibians, bats, rattlesnakes and humans. White-nose syndrome, caused by the fungal skin pathogen Pseudogymnoascus destructans, threatens several hibernating bat species with extinction and there are few effective treatment strategies. The skin microbiome is increasingly understood to play a large role in determining disease outcome. We isolated bacteria from the skin of four bat species, and co-cultured these isolates with P. destructans to identify bacteria that might inhibit or kill P. destructans. We then conducted two reciprocal challenge experiments in vitro with six bacterial isolates (all in the genus Pseudomonas) to quantify the effect of these bacteria on the growth of P. destructans. All six Pseudomonas isolates significantly inhibited growth of P. destructans compared to non-inhibitory control bacteria, and two isolates performed significantly better than others in suppressing P. destructans growth for at least 35 days. In both challenge experiments, the extent of suppression of P. destructans growth was dependent on the initial concentration of P. destructans and the initial concentration of the bacterial isolate. These results show that bacteria found naturally occurring on bats can inhibit the growth of P. destructans in vitro and should be studied further as a possible probiotic to protect bats from white-nose syndrome. In addition, the presence of these bacteria may influence disease outcomes among individuals, populations, and species.

Bacteria Isolated from Bats Inhibit the Growth of Pseudogymnoascus destructans, the Causative Agent of White-Nose Syndrome

PubMed Central

Hoyt, Joseph R.; Cheng, Tina L.; Langwig, Kate E.; Hee, Mallory M.; Frick, Winifred F.; Kilpatrick, A. Marm

2015-01-01

Emerging infectious diseases are a key threat to wildlife. Several fungal skin pathogens have recently emerged and caused widespread mortality in several vertebrate groups, including amphibians, bats, rattlesnakes and humans. White-nose syndrome, caused by the fungal skin pathogen Pseudogymnoascus destructans, threatens several hibernating bat species with extinction and there are few effective treatment strategies. The skin microbiome is increasingly understood to play a large role in determining disease outcome. We isolated bacteria from the skin of four bat species, and co-cultured these isolates with P. destructans to identify bacteria that might inhibit or kill P. destructans. We then conducted two reciprocal challenge experiments in vitro with six bacterial isolates (all in the genus Pseudomonas) to quantify the effect of these bacteria on the growth of P. destructans. All six Pseudomonas isolates significantly inhibited growth of P. destructans compared to non-inhibitory control bacteria, and two isolates performed significantly better than others in suppressing P. destructans growth for at least 35 days. In both challenge experiments, the extent of suppression of P. destructans growth was dependent on the initial concentration of P. destructans and the initial concentration of the bacterial isolate. These results show that bacteria found naturally occurring on bats can inhibit the growth of P. destructans in vitro and should be studied further as a possible probiotic to protect bats from white-nose syndrome. In addition, the presence of these bacteria may influence disease outcomes among individuals, populations, and species. PMID:25853558

Microbial Growth under Supercritical CO2

PubMed Central

Peet, Kyle C.; Freedman, Adam J. E.; Hernandez, Hector H.; Britto, Vanya; Boreham, Chris; Ajo-Franklin, Jonathan B.

2015-01-01

Growth of microorganisms in environments containing CO2 above its critical point is unexpected due to a combination of deleterious effects, including cytoplasmic acidification and membrane destabilization. Thus, supercritical CO2 (scCO2) is generally regarded as a sterilizing agent. We report isolation of bacteria from three sites targeted for geologic carbon dioxide sequestration (GCS) that are capable of growth in pressurized bioreactors containing scCO2. Analysis of 16S rRNA genes from scCO2 enrichment cultures revealed microbial assemblages of varied complexity, including representatives of the genus Bacillus. Propagation of enrichment cultures under scCO2 headspace led to isolation of six strains corresponding to Bacillus cereus, Bacillus subterraneus, Bacillus amyloliquefaciens, Bacillus safensis, and Bacillus megaterium. Isolates are spore-forming, facultative anaerobes and capable of germination and growth under an scCO2 headspace. In addition to these isolates, several Bacillus type strains grew under scCO2, suggesting that this may be a shared feature of spore-forming Bacillus spp. Our results provide direct evidence of microbial activity at the interface between scCO2 and an aqueous phase. Since microbial activity can influence the key mechanisms for permanent storage of sequestered CO2 (i.e., structural, residual, solubility, and mineral trapping), our work suggests that during GCS microorganisms may grow and catalyze biological reactions that influence the fate and transport of CO2 in the deep subsurface. PMID:25681188

An investigation of virulence factors of Legionella pneumophila environmental isolates.

PubMed

Arslan-Aydoğdu, Elif Özlem; Kimiran, Ayten

Nine Legionella pneumophila strains isolated from cooling towers and a standard strain (L. pneumophila serogroup 1, ATCC 33152, Philadelphia 1) were analyzed and compared in terms of motility, flagella structure, ability to form biofilms, enzymatic activities (hemolysin, nucleases, protease, phospholipase A, phospholipase C, acid phosphatase, alkaline phosphatase and lipase), hemagglutination capabilities, and pathogenicity in various host cells (Acanthamoeba castellanii ATCC 30234, mouse peritoneal macrophages and human peripheral monocytes). All the isolates of bacteria appeared to be motile and polar-flagellated and possessed the type-IV fimbria. Upon the evaluation of virulence factors, isolate 4 was found to be the most pathogenic strain, while 6 out of the 9 isolates (the isolates 1, 2, 3, 4, 5, and 7) were more virulent than the ATCC 33152 strain. The different bacterial strains exhibited differences in properties such as adhesion, penetration and reproduction in the hosts, and preferred host type. To our knowledge, this is the first study to compare the virulence of environmental L. pneumophila strains isolated in Turkey, and it provides important information relevant for understanding the epidemiology of L. pneumophila. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Degradation of malathion by salt-marsh microorganisms.

PubMed Central

Bourquin, A W

1977-01-01

Numerous bacteria from a salt-marsh environment are capable of degrading malathion, an organophosphate insecticide, when supplied with additional nutrients as energy and carbon sources. Seven isolates exhibited ability (48 to 90%) to degrade malathion as a sole carbon source. Gas and thin-layer chromatography and infrared spectroscopy confirmed malathion to be degraded via malathion-monocarboxylic acid to the dicarboxylic acid and then to various phosphothionates. These techniques also identified desmethyl-malathion, phosphorthionates, and four-carbon dicarboxylic acids as degradation products formed as a result of phosphatase activity. PMID:192147

Anaerobic Bacteria in Clinical Specimens - Frequent, But a Neglected Lot: A Five Year Experience at a Tertiary Care Hospital.

PubMed

Shenoy, Padmaja Ananth; Vishwanath, Shashidhar; Gawda, Ashwini; Shetty, Seema; Anegundi, Renuka; Varma, Muralidhar; Mukhopadhyay, Chiranjay; Chawla, Kiran

2017-07-01

Anaerobic bacteria which constitute a significant proportion of the normal microbiota also cause variety of infections involving various anatomic sites. Considering the tedious culture techniques with longer turnaround time, anaerobic cultures are usually neglected by clinicians and microbiologists. To study the frequency of isolation of different anaerobic bacteria from various clinical specimens. A retrospective study to analyse the frequency of isolation of different anaerobic bacteria, was conducted over a period of five years from 2011 to 2015 including various clinical specimens submitted to anaerobic division of Microbiology laboratory. Anaerobic bacteria were isolated and identified following standard bacteriological techniques. Pathogenic anaerobes (n=336) were isolated from 278 (12.48%) of overall 2227 specimens processed with an average yield of 1.2 isolates. Anaerobes were isolated as polymicrobial flora with or without aerobic bacterial pathogens in 159 (57.2%) patients. Anaerobic Gram-negative bacilli (140, 41.7%) were the predominant isolates. B. fragilis group (67, 19.9%) were the most commonly isolated anaerobic pathogens. Anaerobes were predominantly isolated from deep seated abscess (23.9%). Pathogenic anaerobes were isolated from various infection sites. Unless culture and susceptibility tests are performed as a routine, true magnitude of antimicrobial resistance among anaerobic pathogens will not be known. Knowledge of the distribution of these organisms may assist in the selection of appropriate empirical therapy for anaerobic infections.

Mutations and Misconceptions: The Isolation and Study of Mutant Bacteria.

ERIC Educational Resources Information Center

Corner, Thomas R.

1992-01-01

Describes simple, inexpensive activities for teaching students about mutants and mutations in bacteria. Explains how to isolate bacteria from soil and leaves and how to grow bacteria on agar or in broth. Describes how to construct a gradient plate for finding the minimum inhibitory concentration of a substance and how to use this set up to find…

Denitrification by extremely halophilic bacteria

NASA Technical Reports Server (NTRS)

Hochstein, L. I.; Tomlinson, G. A.

1985-01-01

Extremely halophilic bacteria were isolated from widely separated sites by anaerobic enrichment in the presence of nitrate. The anaerobic growth of several of these isolates was accompanied by the production of nitrite, nitrous oxide, and dinitrogen. These results are a direct confirmation of the existence of extremely halophilic denitrifying bacteria, and suggest that such bacteria may be common inhabitants of hypersaline environments.

Distribution and Identification of Luminous Bacteria from the Sargasso Sea

PubMed Central

Orndorff, S. A.; Colwell, R. R.

1980-01-01

Vibrio fischeri and Lucibacterium harveyi constituted 75 of the 83 luminous bacteria isolated from Sargasso Sea surface waters. Photobacterium leiognathi and Photobacterium phosphoreum constituted the remainder of the isolates. Luminescent bacteria were recovered at concentrations of 1 to 63 cells per 100 ml from water samples collected at depths of 160 to 320 m. Two water samples collected at the thermocline yielded larger numbers of viable, aerobic heterotrophic and luminous bacteria. Luminescent bacteria were not recovered from surface microlayer samples. The species distribution of the luminous bacteria reflected previously recognized growth patterns; i.e., L. harveyi and V. fischeri were predominant in the upper, warm waters (only one isolate of P. phosphoreum was obtained from surface tropical waters). PMID:16345575

Multidrug-Resistance and Toxic Metal Tolerance of Medically Important Bacteria Isolated from an Aquaculture System

PubMed Central

Resende, Juliana Alves; Silva, Vânia L.; Fontes, Cláudia Oliveira; Souza-Filho, Job Alves; de Oliveira, Tamara Lopes Rocha; Coelho, Cíntia Marques; César, Dionéia Evangelista; Diniz, Cláudio Galuppo

2012-01-01

The use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. We aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. Selective cultures for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC) were obtained from water samples collected in two different year seasons. The isolated bacteria were biochemically identified and antimicrobial and toxic metal susceptibility patterns were determined. Overall, 407 representative strains were recovered. In general, bacteria isolated from fish ponds showed higher multiple antibiotic resistance indices when compared to those isolated from a water-fed canal. Resistance to penicillin and azithromycin was observed more frequently in the GPC group, whereas resistance to ampicillin and ampicillin/sulbactam or gentamicin was observed more frequently in the ENT and NFR groups, respectively. All the isolated bacteria were tolerant to nickel, zinc, chromium and copper at high levels (≥1,024 μg mL−1), whereas tolerance to cadmium and mercury varied among the isolated bacteria (2–1,024 μg mL−1). Multidrug-resistant bacteria were more frequent and diverse in fish ponds than in the water-fed canal. A positive correlation was observed between antimicrobial resistance and metal tolerance. The data point out the need for water treatment associated with the aquaculture system. PMID:22972388

Isolation of bacteria-containing phagosomes by magnetic selection

PubMed Central

Lönnbro, Per; Nordenfelt, Pontus; Tapper, Hans

2008-01-01

Background There is a growing awareness of the importance of intracellular events in determining the outcome of infectious disease. To improve the understanding of such events, like phagosome maturation, we set out to develop a versatile technique for phagosome isolation that is rapid and widely applicable to different pathogens. Results We developed two different protocols to isolate phagosomes containing dead or live bacteria modified with small magnetic particles, in conjunction with a synchronized phagocytosis protocol and nitrogen cavitation. For dead bacteria, we performed analysis of the phagosome samples by microscopy and immunoblot, and demonstrated the appearance of maturation markers on isolated phagosomes. Conclusion We have presented detailed protocols for phagosome isolation, which can be adapted for use with different cell types and prey. The versatility and simplicity of the approach allow better control of phagosome isolation, the parameters of which are critical in studies of host-bacteria interaction and phagosome maturation. PMID:18588680

[Application of anaerobic bacteria detection in oral and maxillofacial infection].

PubMed

Bao, Zhen-ying; Lin, Qin; Meng, Yan-hong; He, Chun; Su, Jia-zeng; Peng, Xin

2016-02-18

To investigate the distribution and drug resistance of anaerobic bacteria in the patients with oral and maxillofacial infection. Aerobic and anaerobic bacteria cultures from 61 specimens of pus from the patients with oral and maxillofacial infection in the Department of Oral and Maxillofacial Surgery, Peking University School of Stomatology were identified. The culture type was evaluated by API 20A kit and drug resistance test was performed by Etest method. The clinical data and antibacterial agents for the treatment of the 61 cases were collected, and the final outcomes were recorded. The bacteria cultures were isolated from all the specimens, with aerobic bacteria only in 6 cases (9.8%), anaerobic bacteria only in 7 cases (11.5%), and both aerobic and anaerobic bacteria in 48 cases (78.7%). There were 55 infected cases (90.2%) with anaerobic bacteria, and 81 anaerobic bacteria stains were isolated. The highest bacteria isolation rate of Gram positive anaerobic bacteria could be found in Peptostreptococcus, Bifidobacterium and Pemphigus propionibacterium. No cefoxitin, amoxicillin/carat acid resistant strain was detected in the above three Gram positive anaerobic bacteria. The highest bacteria isolation rate of Gram negative anaerobic bacteria could be detected in Porphyromonas and Prevotella. No metronidazole, cefoxitin, amoxicillin/carat acid resistant strain was found in the two Gram negative anaerobic bacteria. In the study, 48 patients with oral and maxillofacial infection were treated according to the results of drug resistance testing, and the clinical cure rate was 81.3%. Mixed aerobic and anaerobic bacteria cultures are very common in most oral and maxillofacial infection patients. Anaerobic bacteria culture and drug resistance testing play an important role in clinical treatment.

[Gardnerella vaginalis in infections of reproductive organs].

PubMed

Kasprowicz, A; Białecka, A

1993-01-01

The study was aimed at multidirectional studies on bacteria isolated from smears from vagina and cervix uteri in 226 patients with inflammatory states of their reproductive organs. Most frequently isolated aerobic bacteria were Gram-negative--27%, mainly E. coli, and Enterococcus faecalis--in 18% of cases. Anaerobic bacteria were isolated in 81% of cases: Gardnerella vaginalis was isolated in 28% and Lactobacillus in 53% of cases. Other anaerobic bacteria were: Peptococcus asaccharolyticus (15.5%), Streptococcus sp. (15.9%), and Bacteroides melaninogenicus (14.1%). Gardnerella vaginalis was most frequently found in chronic cases of vaginosis (41.7%). All strains of G. vaginalis were susceptible to cefotaxime, while 15-40% of them were resistant to gentamycin, tetracycline and metronidazole.

Novel Thermo-Acidophilic Bacteria Isolated from Geothermal Sites in Yellowstone National Park: Physiological and Phylogenetic Characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

D. B. Johnson; N. Okibe; F. F. Roberto

Moderately thermophilic acidophilic bacteria were isolated from geothermal (30–83 °C) acidic (pH 2.7– 3.7) sites in Yellowstone National Park. The temperature maxima and pH minima of the isolates ranged from 50 to 65 °C, and pH 1.0–1.9. Eight of the bacteria were able to catalyze the dissimilatory oxidation of ferrous iron, and eleven could reduce ferric iron to ferrous iron in anaerobic cultures. Several of the isolates could also oxidize tetrathionate. Six of the iron-oxidizing isolates, and one obligate heterotroph, were low G+C gram-positive bacteria (Firmicutes). The former included three Sulfobacillus-like isolates (two closely related to a previously isolated Yellowstonemore » strain, and the third to a mesophilic bacterium isolated from Montserrat), while the other three appeared to belong to a different genus. The other two iron-oxidizers were an Actinobacterium (related to Acidimicrobium ferrooxidans) and a Methylobacterium-like isolate (a genus within the a-Proteobacteria that has not previously been found to contain either iron-oxidizers or acidophiles). The other three (heterotrophic) isolates were also a-Proteobacteria and appeared be a novel thermophilic Acidisphaera sp. An ARDREA protocol was developed to discriminate between the iron-oxidizing isolates. Digestion of amplified rRNA genes with two restriction enzymes (SnaBI and BsaAI) separated these bacteria into five distinct groups; this result was confirmed by analysis of sequenced rRNA genes.« less

Fimbrial phase variation and systemic E. coli infection studied in the mouse peritonitis model.

PubMed

Nowicki, B; Vuopio-Varkila, J; Viljanen, P; Korhonen, T K; Mäkelä, P H

1986-08-01

Mouse peritonitis induced by intraperitoneal injection of a virulent (LD50 4 x 10(5) E. coli 018:K1:H7 strain isolated from neonatal meningitis was studied. These bacteria are capable of producing both type 1 and S fimbriae, binding to mannose or sialic acid containing glycoconjugates, respectively; the production of both fimbrial types is subject to phase variation. A broth culture of the bacteria was fractionated into subpopulations containing either type 1 or S fimbriae or neither (nonfimbriated cells), and each fraction, grown in broth to logarithmic growth phase, was used to infect groups of mice. The type 1 fraction was associated with decreased virulence as the fraction was eliminated rapidly without causing a progressive infection even at 10(6) bacteria/mouse, whereas both S and nonfimbriated cells started rapid multiplication in the peritoneal cavity and spread to the blood. In nonfibriated cells, however, S fimbriae production was induced at the same time so that at 1 h after injection, 60-70% of the bacteria in the peritoneal cavity and in the blood of the mice had S fimbriae. The injected S-fimbriated fraction remained completely S-fimbriated. Rapid induction of S fimbriae also took place in vitro when the nonfimbriated bacteria were grown in mouse serum or peritoneal fluid. Anti-S serum protected the mice from a lethal dose of S-fimbriated bacteria.

Stimulation of Lactic Acid Bacteria by a Micrococcus Isolate: Evidence for Multiple Effects

PubMed Central

Nath, K. R.; Wagner, B. J.

1973-01-01

Growth of, and rate of acid production by, six cultures of lactic acid bacteria were increased in the presence of Micrococcus isolate F4 or a preparation of its capsular material. Concentrations of hydrogen peroxide found in pure cultures of the lactic acid bacteria were not detectable, or were greatly reduced, in mixed culture with Micrococcus isolate F4. The capsular material was not as effective as whole cells in preventing accumulation of H2O2. Catalase stimulated growth of, and the rate of acid production by, the lactic acid bacteria, but not to the same extent as Micrococcus isolate F4 in some cultures. The existence of two mechanisms for micrococcal stimulation of the lactic acid bacteria is postulated. One mechanism involves removal of H2O2; the other has not been characterized. PMID:4199337

Attempt to develop live attenuated bacterial vaccines by selecting resistance to gossypol, proflavine hemisulfate, novobiocin, or ciprofloxacin.

PubMed

Pridgeon, Julia W; Klesius, Phillip H; Yildirim-Aksoy, Mediha

2013-04-26

In an attempt to develop attenuated bacteria as potential live vaccines, four chemicals (gossypol, proflavine hemisulfate, novobiocin, and ciprofloxacin) were used to modify the following four genera of bacteria through chemical-resistance strategy: (1) Aeromonas hydrophila (9 isolates); (2) Edwardsiella tarda (9 isolates); (3) Streptococcus iniae (9 isolates); and (4) S. agalactiae (11 isolates). All bacteria used in this study were able to develop high resistance to gossypol. However, only some bacteria were able to develop resistance to proflavine hemisulfate, novobiocin, or ciprofloxacin. When the virulence of resistant bacteria was tested in tilapia or catfish, none of the gossypol-resistant isolate was attenuated, whereas majority of the proflavine hemisulfate-resistant isolates were attenuated. However, all proflavine hemisulfate-attenuated bacteria failed to provide significant protection to fish. Eight novobiocin- or ciprofloxacin-resistant Gram-positive bacteria (S. agalactiae and S. inaie) were found to be attenuated. However, none of them offered protection higher than 70%. Of seven attenuated novobiocin- or ciprofloxacin-resistant Gram-negative isolates (A. hydrophila and E. tarda), only one (novobiocin-resistant E. tarda 30305) was found to safe and highly efficacious. When E. tarda 30305-novo vaccinated Nile tilapia were challenged by its virulent E. tarda 30305, relative percent of survival of vaccinated fish at 14- and 28-days post vaccination (dpv) was 100% and 92%, respectively. Similarly, E. tarda 30305-novo offered 100% protection to channel catfish against challenges with virulent parent isolate E. tarda 30305 at both 14- and 28-dpv. Our results suggest that the development of live attenuated bacterial vaccines that are safe and efficacious is challenging, although it is feasible. Published by Elsevier Ltd.

The microbiology of ethmoid and maxillary sinuses in patients with chronic sinusitis.

PubMed

Aral, Murat; Keles, Erol; Kaygusuz, Irfan

2003-01-01

To investigate aerob-anaerob microorganisms growth in maxillary and ethmoid sinuses by evaluating aspiration materials from patients with chronic sinusitis. The study was performed prospectively, and there were 31 patients (23 men, 8 women; mean age, 31.4+/-14.15, between 18-65 years) who had endoscopic sinus surgery because of chronic sinusitis. During the operation, when the maxillary sinus ostium and ethmoid sinus were opened, readily aspirated materials from sinuses were evaluated regarding aerob and anaerob bacteria. Nose and throat swap samples were collected preoperatively to determine the upper respiratory tract flora and also to understand the relationship between the flora and the microorganisms aspirated from sinuses. Total aerob bacteria count, which was isolated from preoperative nasal swab cultures, was 36, and aerob-anaerob bacteria count that included cultures taken from maxillary and ethmoid sinuses during the functional endoscopic sinus surgery was 42. For each 2 samples, the most common isolated aerob bacteria were coagulase (-) staphylococci. Microorganisms were isolated in 87.0% of 27 patients, in which cultures taken from maxillary and ethmoid sinuses during the functional endoscopic sinus surgery were included. It is determined that the isolated aerob bacteria rate was 90.4%, and the isolated anaerob bacteria rate was 14.2%. All of the 6 samples in which anaerob bacteria isolated were all maxillary sinus aspiration materials. Microorganisms that isolated from the nose and the sinuses were similar with the rate of 25.8%, and microorganisms that isolated from the throat cultures and sinuses were similar with the rate of 22.5%. This study reveals the aerob and anaerob microbiology of the maxillary and ethmoid sinuses so the treatment of chronic sinusitis will be easier.

The biodiscovery potential of marine bacteria: an investigation of phylogeny and function

PubMed Central

Mühling, Martin; Joint, Ian; Willetts, Andrew J

2013-01-01

Summary A collection of marine bacteria isolated from a temperate coastal zone has been screened in a programme of biodiscovery. A total of 34 enzymes with biotechnological potential were screened in 374 isolates of marine bacteria. Only two enzymes were found in all isolates while the majority of enzyme activities were present in a smaller proportion of the isolates. A cluster analysis demonstrated no significant correlation between taxonomy and enzyme function. However, there was evidence of co-occurrence of some enzyme activity in the same isolate. In this study marine Proteobacteria had a higher complement of enzymes with biodiscovery potential than Actinobacteria; this contrasts with the terrestrial environment where the Actinobacteria phylum is a proven source of enzymes with important industrial applications. In addition, a number of novel enzyme functions were more abundant in this marine culture collection than would be expected on the basis of knowledge from terrestrial bacteria. There is a strong case for future investigation of marine bacteria as a source for biodiscovery. PMID:23557256

Genetic Diversity and Association Characters of Bacteria Isolated from Arbuscular Mycorrhizal Fungal Spore Walls

PubMed Central

Selvakumar, Gopal; Krishnamoorthy, Ramasamy; Kim, Kiyoon; Sa, Tong-Min

2016-01-01

Association between arbuscular mycorrhizal fungi (AMF) and bacteria has long been studied. However, the factors influencing their association in the natural environment is still unknown. This study aimed to isolate bacteria associated with spore walls of AMF and identify their potential characters for association. Spores collected from coastal reclamation land were differentiated based on their morphology and identified by 18S rDNA sequencing as Funneliformis caledonium, Racocetra alborosea and Funneliformis mosseae. Bacteria associated with AMF spore walls were isolated after treating them with disinfection solution at different time intervals. After 0, 10 and 20 min of spore disinfection, 86, 24 and 10 spore associated bacteria (SAB) were isolated, respectively. BOX-PCR fingerprinting analysis showed that diverse bacterial communities were associated to AMF spores. Bacteria belonging to the same genera could associate with different AMF spores. Gram positive bacteria were more closely associated with AMF spores. Isolated SAB were characterized and tested for spore association characters such as chitinase, protease, cellulase enzymes and exopolysaccharide production (EPS). Among the 120 SAB, 113 SAB were able to show one or more characters for association and seven SAB did not show any association characters. The 16S rDNA sequence of SAB revealed that bacteria belonging to the phyla Firmicutes, Proteobacteria, Actinobacteria and Bactereiodes were associated with AMF spore walls. PMID:27479250

Airborne Bacteria in an Urban Environment

PubMed Central

Mancinelli, Rocco L.; Shulls, Wells A.

1978-01-01

Samples were taken at random intervals over a 2-year period from urban air and tested for viable bacteria. The number of bacteria in each sample was determined, and each organism isolated was identified by its morphological and biochemical characteristics. The number of bacteria found ranged from 0.013 to 1.88 organisms per liter of air sampled. Representatives of 19 different genera were found in 21 samples. The most frequently isolated organisms and their percent of occurence were Micrococcus (41%), Staphylococcus (11%), and Aerococcus (8%). The bacteria isolated were correlated with various weather and air pollution parameters using the Pearson product-moment correlation coefficient method. Statistically significant correlations were found between the number of viable bacteria isolated and the concentrations of nitric oxide (−0.45), nitrogen dioxide (+0.43), and suspended particulate pollutants (+0.56). Calculated individually, the total number of Micrococcus, Aerococcus, and Staphylococcus, number of rods, and number of cocci isolated showed negative correlations with nitric oxide and positive correlations with nitrogen dioxide and particulates. Statistically significant positive correlations were found between the total number of rods isolated and the concentration of nitrogen dioxide (+0.54) and the percent relative humidity (+0.43). The other parameters tested, sulfur dioxide, hydrocarbons, and temperature, showed no significant correlations. Images PMID:677875

Detection of tlh and tdh genes in Vibrio Parahaemolyticus inhabiting farmed water ecosystem used for L. Vannamei aquaculture

NASA Astrophysics Data System (ADS)

Nawan Hasrimi, Adila; Budiharjo, Anto; Nur Jannah, Siti

2018-05-01

Vibrio parahaemolyticus is hallophilic gram-negative bacteria that live as natural inhabitant in aquatic environment. All Vibrio parahaemolyticus strain known to have thermolabile hemolysin encoded by tlh gene as species marker. Thermostable direct hemolysin encoded by tdh gene is responsible for regulating virulence factor in Vibrio parhaemolyticus. Aim of this research is to detect tlh and tdh gene from water of L. vannamei aquaculture in Rembang regency. Colonies of green-blueish bacteria grew from isolation of L. vannamei aquaculture water in CD-VP media which was identified as Vibrio parahaemolyticus. Colonies of V. parahaemolyticus grew to be small and green-blueish bacteria colonies in TCBS agar. Result of molecular analysis showed that bacteria isolated from water sample are specifically identified as Vibrio parahaemolyticus bacteria by the detection of tlh gene. Vibrio parahaemolyticus isolated from water of L. vannamei aquaculture detected as tdh negative that indicates tdh gene is not present in isolated bacteria. Vibrio parahaemolyticus isolate were cultured in Wagatsuma agar for tdh gene confirmation test that showed Kanagawa negative result, which indicated that V. parahaemolyticus did not produce thermostable direct hemolysin. These results showed that Vibrio parahaemolyticus isolated from aquatic environment of L. vannamei aquaculture in Rembang regency did not show virulence factors.

[Selective-differential nutrient medium "Shewanella IRHLS agar" for isolation of Shewanella genus bacteria].

PubMed

Sivolodsky, E P

2015-01-01

Development of a selective-differential nutrient medium for isolation of Shewanella genus bacteria. 73 strains of Shewanella bacteria (S. algae--3, S. baltica--26, S. putrefaciens--44) and 80 strains of 22 other bacteria genera were used. Shewanella species were identified by methods and criteria proposed by Nozue H. et al., 1992; Khashe S. et al., 1998. Nutrient media "Shewanella IRHLS Agar" for shewanella isolation was developed. Medium selective factors: irgazan DP-300 (I). 0.14-0.2 g/l and rifampicin (R) 0.0005-0.001 g/l. Shevanella colonies were detected by the production of hydrogen sulfide (H), lipase presence (L), lack of sorbitol fermentation (S). The medium suppressed the growth of hydrogen sulfide producers (Salmonella, Proteus) and blocked hydrogen sulfide production by Citrobacter. Growth of Escherichia, Enterobacter, Klebsiella, Shigella, Staphylococcus, Bacillus was also suppressed, Analytical sensitivity of the medium was 1-2 CFU/ml for Shewanella and Stenotrophomonas, Aerombnas, Serratia genera bacteria. 72 strains of Shewanella were isolated from water of Neva river in this medium, 91.7 ± 3.2% of those produced H2S. 1 strain of S. algae was isolated from clinical material. The developed media allows to use it in a complex for Stenotrophomo- nas sp., Aeromonas sp., Serratia sp., Citrobactersp. and Shewanella bacteria isolation.

Escherichia coli B2 strains prevalent in inflammatory bowel disease patients have distinct metabolic capabilities that enable colonization of intestinal mucosa.

PubMed

Fang, Xin; Monk, Jonathan M; Mih, Nathan; Du, Bin; Sastry, Anand V; Kavvas, Erol; Seif, Yara; Smarr, Larry; Palsson, Bernhard O

2018-06-11

Escherichia coli is considered a leading bacterial trigger of inflammatory bowel disease (IBD). E. coli isolates from IBD patients primarily belong to phylogroup B2. Previous studies have focused on broad comparative genomic analysis of E. coli B2 isolates, and identified virulence factors that allow B2 strains to reside within human intestinal mucosa. Metabolic capabilities of E. coli strains have been shown to be related to their colonization site, but remain unexplored in IBD-associated strains. In this study, we utilized pan-genome analysis and genome-scale models (GEMs) of metabolism to study metabolic capabilities of IBD-associated E. coli B2 strains. The study yielded three results: i) Pan-genome analysis of 110 E. coli strains (including 53 isolates from IBD studies) revealed discriminating metabolic genes between B2 strains and other strains; ii) Both comparative genomic analysis and GEMs suggested that B2 strains have an advantage in degrading and utilizing sugars derived from mucus glycan, and iii) GEMs revealed distinct metabolic features in B2 strains that potentially allow them to utilize energy more efficiently. For example, B2 strains lack the enzymes to degrade amadori products, but instead rely on neighboring bacteria to convert these substrates into a more readily usable and potentially less sought after product. Taken together, these results suggest that the metabolic capabilities of B2 strains vary significantly from those of other strains, enabling B2 strains to colonize intestinal mucosa.The results from this study motivate a broad experimental assessment of the nutritional effects on E. coli B2 pathophysiology in IBD patients.

Methane production from grape skins. Final technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yunghans, W.N.

1981-10-09

Methane production from grape pomace was measured for a 50-day digestion period. Gas production was calculated to be 2400 ft/sup 3//10 d/ton at 53% methane content. Microorganisms particularly a fungus which grows on grape pomace and lignin was isolated. Lignin content of pomace was measured at approximately 60%. Lignin is slowly digested and may represent a residue which requires long term digestion. Research is continuing on isolation of anaerobic methane bacteria and codigestion of pomace with enzymes as cellulase and pectinase. The sewage sludge functioned adequately as a mixed source of organisms capable of digesting grape pomace. A sediment frommore » stored grape juice produced significant amounts of methane and represents a nutrient substrate for additional studies on continuous flow methane production. 3 figs.« less

Salmonella as a biological "Trojan horse" for neoplasia: future possibilities including brain cancer.

PubMed

Mlynarczyk, Gregory S A; Berg, Carrie A; Withrock, Isabelle C; Fick, Meghan E; Anderson, Stephen J; Laboissonniere, Lauren A; Jefferson, Matthew A; Brewer, Matthew T; Stock, Matthew L; Lange, Jennifer K; Luna, K C; Acharya, Sreemoyee; Kanuri, Sriharsha; Sharma, Shaunik; Kondru, Naveen C; McCormack, Garrett R; Carlson, Steve A

2014-09-01

This manuscript considers available evidence that a specific Salmonella strain could be used as an effective orally-administered option for cancer therapy involving the brain. It has been established that Salmonella preferentially colonizes neoplastic tissue and thrives as a facultative anaerobe in the intra-tumor environment. Although Salmonella accumulates in tumors by passive processes, it is still possible for lipopolysaccharide to cause sepsis and endotoxic shock during the migration of bacteria to the tumor site. An LPS-free version of a recently identified Salmonella isolate may have the capability to circumvent the blood brain barrier and provide a safer method of reaching brain tumors. This isolate merits further research as a "Trojan horse" for future oral biotherapy of brain cancer. Copyright © 2014 Elsevier Ltd. All rights reserved.

Rapid phenotypic antimicrobial susceptibility testing using nanoliter arrays.

PubMed

Avesar, Jonathan; Rosenfeld, Dekel; Truman-Rosentsvit, Marianna; Ben-Arye, Tom; Geffen, Yuval; Bercovici, Moran; Levenberg, Shulamit

2017-07-18

Antibiotic resistance is a major global health concern that requires action across all sectors of society. In particular, to allow conservative and effective use of antibiotics clinical settings require better diagnostic tools that provide rapid determination of antimicrobial susceptibility. We present a method for rapid and scalable antimicrobial susceptibility testing using stationary nanoliter droplet arrays that is capable of delivering results in approximately half the time of conventional methods, allowing its results to be used the same working day. In addition, we present an algorithm for automated data analysis and a multiplexing system promoting practicality and translatability for clinical settings. We test the efficacy of our approach on numerous clinical isolates and demonstrate a 2-d reduction in diagnostic time when testing bacteria isolated directly from urine samples.

Isolation And Partial Characterization Of Bacteria Activity Associated With Gorgonian Euplexaura sp. Against Methicillin-Resistant Staphylococcus aureus (MRSA)

NASA Astrophysics Data System (ADS)

Kristiana, R.; Ayuningrum, D.; Asagabaldan, M. A.; Nuryadi, H.; Sabdono, A.; Radjasa, O. K.; Trianto, A.

2017-02-01

Methicillin-resistant Staphylococcus aureus (MRSA) infection has emerged in around the world and has been resistance to ciprofloxacin, erythromycin, clindamycin. The aims of this study were to isolate, to investigate and to characterize bacterial symbionts gorgonian having activity against MRSA. Euplexaura sp. was collected from Panjang Island, Jepara, Indonesia by snorkling 2-5 m in depth. Bacterias were isolated by using spesific media with dilution method. Bacterias were conducted by using the streak method. Antibacterial activity was investigated by overlay method. The potent bacteria was identified by using molecular identification (DNA extraction, electrophoresis, PCR and phylogenetic analysis using 16S rDNA genes with actinobacteria-spesific primers) and bio-chemical test (among 5 isolated bacteria from gorgonian showed activity against MRSA). The strain PG-344 was the best candidat that has an inhibition zone against MRSA. The result of sequencing bacteria is 100% closely related with Virgibacillus salarius. This becomes a potential new bioactive compounds to against MRSA that can be a new drug discovery.

Optimization of isolation and cultivation of bacterial endophytes through addition of plant extract to nutrient media

PubMed Central

Eevers, N; Gielen, M; Sánchez-López, A; Jaspers, S; White, J C; Vangronsveld, J; Weyens, N

2015-01-01

Many endophytes have beneficial effects on plants and can be exploited in biotechnological applications. Studies hypothesize that only 0.001–1% of all plant-associated bacteria are cultivable. Moreover, even after successful isolations, many endophytic bacteria often show reduced regrowth capacity. This research aimed to optimize isolation processes and culturing these bacteria afterwards. We compared several minimal and complex media in a screening. Beside the media themselves, two gelling agents and adding plant extract to media were investigated to enhance the number and diversity of endophytes as well as the growth capacity when regrown after isolation. In this work, 869 medium delivered the highest numbers of cultivable bacteria, as well as the highest diversity. When comparing gelling agents, no differences were observed in the numbers of bacteria. Adding plant extract to the media lead to a slight increase in diversity. However, when adding plant extract to improve the regrowth capacity, sharp increases of viable bacteria occurred in both rich and minimal media. PMID:25997013

Identification of entomopathogenic nematodes and symbiotic bacteria from Nam Nao National Park in Thailand and larvicidal activity of symbiotic bacteria against Aedes aegypti and Aedes albopictus

PubMed Central

Yooyangket, Temsiri; Muangpat, Paramaporn; Polseela, Raxsina; Tandhavanant, Sarunporn; Thanwisai, Aunchalee

2018-01-01

Entomopathogenic nematodes (EPNs) that are symbiotically associated with Xenorhabdus and Photorhabdus bacteria can kill target insects via direct infection and toxin action. There are limited reports identifying such organisms in the National Park of Thailand. Therefore, the objectives of this study were to identify EPNs and symbiotic bacteria from Nam Nao National Park, Phetchabun Province, Thailand and to evaluate the larvicidal activity of bacteria against Aedes aegypti and Ae. albopictus. A total of 12 EPN isolates belonging to Steinernema and Heterorhabditis were obtained form 940 soil samples between February 2014 and July 2016. EPNs were molecularly identified as S. websteri (10 isolates) and H. baujardi (2 isolates). Symbiotic bacteria were isolated from EPNs and molecularly identified as P. luminescens subsp. akhurstii (13 isolates), X. stockiae (11 isolates), X. vietnamensis (2 isolates) and X. japonica (1 isolate). For the bioassay, bacterial suspensions were evaluated for toxicity against third to early fourth instar larvae of Aedes spp. The larvae of both Aedes species were orally susceptible to symbiotic bacteria. The highest larval mortality of Ae. aegypti was 99% after exposure to X. stockiae (bNN112.3_TH) at 96 h, and the highest mortality of Ae. albopictus was 98% after exposure to P. luminescens subsp. akhurstii (bNN121.4_TH) at 96 h. In contrast to the control groups (Escherichia coli and distilled water), the mortality rate of both mosquito larvae ranged between 0 and 7% at 72 h. Here, we report the first observation of X. vietnamensis in Thailand. Additionally, we report the first observation of P. luminescens subsp. akhurstii associated with H. baujardi in Thailand. X. stockiae has potential to be a biocontrol agent for mosquitoes. This investigation provides a survey of the basic diversity of EPNs and symbiotic bacteria in the National Park of Thailand, and it is a bacterial resource for further studies of bioactive compounds. PMID:29641570

Identification of entomopathogenic nematodes and symbiotic bacteria from Nam Nao National Park in Thailand and larvicidal activity of symbiotic bacteria against Aedes aegypti and Aedes albopictus.

PubMed

Yooyangket, Temsiri; Muangpat, Paramaporn; Polseela, Raxsina; Tandhavanant, Sarunporn; Thanwisai, Aunchalee; Vitta, Apichat

2018-01-01

Entomopathogenic nematodes (EPNs) that are symbiotically associated with Xenorhabdus and Photorhabdus bacteria can kill target insects via direct infection and toxin action. There are limited reports identifying such organisms in the National Park of Thailand. Therefore, the objectives of this study were to identify EPNs and symbiotic bacteria from Nam Nao National Park, Phetchabun Province, Thailand and to evaluate the larvicidal activity of bacteria against Aedes aegypti and Ae. albopictus. A total of 12 EPN isolates belonging to Steinernema and Heterorhabditis were obtained form 940 soil samples between February 2014 and July 2016. EPNs were molecularly identified as S. websteri (10 isolates) and H. baujardi (2 isolates). Symbiotic bacteria were isolated from EPNs and molecularly identified as P. luminescens subsp. akhurstii (13 isolates), X. stockiae (11 isolates), X. vietnamensis (2 isolates) and X. japonica (1 isolate). For the bioassay, bacterial suspensions were evaluated for toxicity against third to early fourth instar larvae of Aedes spp. The larvae of both Aedes species were orally susceptible to symbiotic bacteria. The highest larval mortality of Ae. aegypti was 99% after exposure to X. stockiae (bNN112.3_TH) at 96 h, and the highest mortality of Ae. albopictus was 98% after exposure to P. luminescens subsp. akhurstii (bNN121.4_TH) at 96 h. In contrast to the control groups (Escherichia coli and distilled water), the mortality rate of both mosquito larvae ranged between 0 and 7% at 72 h. Here, we report the first observation of X. vietnamensis in Thailand. Additionally, we report the first observation of P. luminescens subsp. akhurstii associated with H. baujardi in Thailand. X. stockiae has potential to be a biocontrol agent for mosquitoes. This investigation provides a survey of the basic diversity of EPNs and symbiotic bacteria in the National Park of Thailand, and it is a bacterial resource for further studies of bioactive compounds.

Poly-γ-Glutamic Acids Contribute to Biofilm Formation and Plant Root Colonization in Selected Environmental Isolates of Bacillus subtilis

PubMed Central

Yu, Yiyang; Yan, Fang; Chen, Yun; Jin, Christopher; Guo, Jian-Hua; Chai, Yunrong

2016-01-01

Bacillus subtilis is long known to produce poly-γ-glutamic acids (γ-PGA) as one of the major secreted polymeric substances. In B. subtilis, the regulation of γ-PGA production and its physiological role are still unclear. B. subtilis is also capable of forming structurally complex multicellular communities, or biofilms, in which an extracellular matrix consisting of secreted proteins and polysaccharides holds individual cells together. Biofilms were shown to facilitate B. subtilis–plant interactions. In this study, we show that different environmental isolates of B. subtilis, all capable of forming biofilms, vary significantly in γ-PGA production. This is possibly due to differential regulation of γ-PGA biosynthesis genes. In many of those environmental isolates, γ-PGA seems to contribute to robustness and complex morphology of the colony biofilms, suggesting a role of γ-PGA in biofilm formation. Our evidence further shows that in selected B. subtilis strains, γ-PGA also plays a role in root colonization by the bacteria, pinpointing a possible function of γ-PGA in B. subtilis–plant interactions. Finally, we found that several pathways co-regulate both γ-PGA biosynthesis genes and genes for the biofilm matrix in B. subtilis, but in an opposing fashion. We discussed potential biological significance of that. PMID:27891125

Human milk is a source of lactic acid bacteria for the infant gut.

PubMed

Martín, Rocío; Langa, Susana; Reviriego, Carlota; Jimínez, Esther; Marín, María L; Xaus, Jordi; Fernández, Leonides; Rodríguez, Juan M

2003-12-01

To investigate whether human breast milk contains potentially probiotic lactic acid bacteria, and therefore, whether it can be considered a synbiotic food. Study design Lactic acid bacteria were isolated from milk, mammary areola, and breast skin of eight healthy mothers and oral swabs and feces of their respective breast-fed infants. Some isolates (178 from each mother and newborn pair) were randomly selected and submitted to randomly amplified polymorphic DNA (RAPD) polymerase chain reaction analysis, and those that displayed identical RAPD patterns were identified by 16S rDNA sequencing. Within each mother and newborn pair, some rod-shaped lactic acid bacteria isolated from mammary areola, breast milk, and infant oral swabs and feces displayed identical RAPD profiles. All of them, independently from the mother and child pair, were identified as Lactobacillus gasseri. Similarly, among coccoid lactic acid bacteria from these different sources, some shared an identical RAPD pattern and were identified as Enterococcus faecium. In contrast, none of the lactic acid bacteria isolated from breast skin shared RAPD profiles with lactic acid bacteria of the other sources. Breast-feeding can be a significant source of lactic acid bacteria to the infant gut. Lactic acid bacteria present in milk may have an endogenous origin and may not be the result of contamination from the surrounding breast skin.

Cytochrome components of nitrate- and sulfate-respiring Desulfovibrio desulfuricans ATCC 27774.

PubMed Central

Liu, M C; Costa, C; Coutinho, I B; Moura, J J; Moura, I; Xavier, A V; LeGall, J

1988-01-01

Three multiheme c-type cytochromes--the tetraheme cytochrome c3 (molecular weight [MW] 13,500), a dodecaheme cytochrome c (MW 40,800), and a "split-Soret" cytochrome c (MW 51,540), which is a dimer with 2 hemes per subunit (MW 26,300)--were isolated from the soluble fraction of Desulfovibrio desulfuricans (ATCC 27774) grown under nitrate- or sulfate-respiring conditions. Two of them, the dodecaheme and the split-Soret cytochromes, showed no similarities to any of the c-type cytochromes isolated from other sulfate-reducing bacteria, while the tetraheme cytochrome c3 appeared to be analogous to the cytochrome c3 found in other sulfate-reducing bacteria. For all three multiheme c-type cytochromes isolated, the homologous proteins from nitrate- and sulfate-grown cells were indistinguishable in amino acid composition, physical properties, and spectroscopic characteristics. It therefore appears that the same c-type cytochrome components are present when D. desulfuricans ATCC 27774 cells are grown under either condition. This is in contrast to the considerable difference found in Pseudomonas perfectomarina (Liu et al., J. Bacteriol. 154:278-286, 1983), a marine denitrifier, when the cells are grown on nitrate or oxygen as the terminal electron acceptor. In addition, two spectroscopy methods capable of revealing minute structural variations in proteins provided identical information about the tetraheme cytochrome c3 from nitrate-grown and sulfate-grown cells. PMID:2848008

Ultra performance liquid chromatography/quadrupole-time-of-flight mass spectrometry for determination of avicularin metabolites produced by a human intestinal bacterium.

PubMed

Zhao, Min; Xu, Jun; Qian, Dawei; Guo, Jianming; Jiang, Shu; Shang, Er-xin; Duan, Jin-ao; Yang, Jing; Du, Le-yue

2014-02-15

Intestinal bacteria from human were screened to isolate the specific bacteria involved in the metabolism of avicularin. A Gram-positive anaerobic bacterium, strain 46, capable of metabolizing avicularin (quercetin-3-O-arabinoside) was isolated for the first time. Its 16S rRNA gene sequence showed 99% similarity with that of Bacillus. Then strain 46 was identified as a species of the genus Bacillus, and was named to be Bacillus sp. 46. Additionally, the metabolites were analyzed by ultra performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS) technique combined with Metabolynx™ software. The structure of these metabolites were proposed and confirmed by comparing the UPLC retention time and MS/MS spectrum with that of authentic standards. Parent compound and six metabolites were detected in the isolated bacterial samples compared with blank samples. Avicularin (M1) was anaerobic metabolized to its aglycone quercetin (M2) and methoxylated avicularin (M3, M4), then quercetin was converted to quercetin glycosides: quercetin-3-O-rhamnoside (M5), quercetin-3-O-glucoside (M6) and quercetin-7-O-glucoside (M7) by Bacillus sp. 46. The metabolic pathway and metabolites of avicularin by the intestinal bacterium Bacillus sp. 46 were reported for the first time. Copyright © 2014 Elsevier B.V. All rights reserved.

Halophilic starch degrading bacteria isolated from Sambhar Lake, India, as potential anode catalyst in microbial fuel cell: A promising process for saline water treatment.

PubMed

Vijay, Ankisha; Arora, Shivam; Gupta, Sandeep; Chhabra, Meenu

2018-05-01

In this study, Microbial Fuel Cell (MFC) capable of treating saline starch water was developed. Sodium chloride (NaCl) concentrations ranging from 500 mM to 3000 mM were tested at the anode. Nitrate was used as an electron acceptor at the biocathode. The halophilic bacteria were isolated from Sambhar Lake, India. Results indicated successful removal of starch (1.83 kg/m 3 -d) and nitrate (0.13 kg/m 3 -d NO 3 - -N) with concomitant power output of 207.05 mW/m 2 at 1000 mM NaCl concentration. An increase in power density from 71.06 mW/m 2 to 207.05 mW/m 2 (2.92 folds) was observed when NaCl concentration was increased from 500 mM to 1000 mM. A decline in power density was observed when the salt concentrations >1000 mM were used. Concentration of 3000 mM supported power output as well as the highest starch degradation (3.2 kg/m 3 -d) and amylase activity of 2.26 IU/ml. The halophilic exoelectrogens were isolated and identified. The present study demonstrates the utility of MFC for degrading starch in saline water. Copyright © 2018 Elsevier Ltd. All rights reserved.

Corrosion of iron by iodide-oxidizing bacteria isolated from brine in an iodine production facility.

PubMed

Wakai, Satoshi; Ito, Kimio; Iino, Takao; Tomoe, Yasuyoshi; Mori, Koji; Harayama, Shigeaki

2014-10-01

Elemental iodine is produced in Japan from underground brine (fossil salt water). Carbon steel pipes in an iodine production facility at Chiba, Japan, for brine conveyance were found to corrode more rapidly than those in other facilities. The corroding activity of iodide-containing brine from the facility was examined by immersing carbon steel coupons in "native" and "filter-sterilized" brine samples. The dissolution of iron from the coupons immersed in native brine was threefold to fourfold higher than that in the filter-sterilized brine. Denaturing gradient gel electrophoresis analyses revealed that iodide-oxidizing bacteria (IOBs) were predominant in the coupon-containing native brine samples. IOBs were also detected in a corrosion deposit on the inner surface of a corroded pipe. These results strongly suggested the involvement of IOBs in the corrosion of the carbon steel pipes. Of the six bacterial strains isolated from a brine sample, four were capable of oxidizing iodide ion (I(-)) into molecular iodine (I(2)), and these strains were further phylogenetically classified into two groups. The iron-corroding activity of each of the isolates from the two groups was examined. Both strains corroded iron in the presence of potassium iodide in a concentration-dependent manner. This is the first report providing direct evidence that IOBs are involved in iron corrosion. Further, possible mechanisms by which IOBs corrode iron are discussed.

Identification and phylogenetic analysis of new sulfate-reducing bacteria isolated from oilfield samples.

PubMed

Chen, Wu; Xiang, Fu; Fu, Jie; Wang, Qiang; Wang, Wenjun; Zeng, Qingfu; Yu, Longjiang

2009-01-01

Microbiologically influenced corrosion (MIC) caused by sulfate-reducing bacteria (SRB) has been investigated in an oilfield injection water system. Strain CW-01 was isolated from an oilfield and strain CW-04 was isolated from biofilm dirt of pipeline walls. The strains were facultative anaerobes, non-motile, Gram-positive, pole flagellum, and spore-forming curved rods. The growth was observed over the temperature range 20-70 degrees C. Strain CW-01 grew optimally at 37 degrees C. The pH range for growth was 3.0-11, optimal at pH 6.0. Strain CW-04 grew optimally at 48 degrees C. The pH range for growth was 3.0-10, optimal at pH 7.2. The strains grew at a very broad range of salt concentrations. Optimal growth was observed with 1.5 g/L NaCl for strain CW-01 and 0.7 g/L NaCl for strain CW-04. The strains showed most similarity in physiological characteristics, except for acetone and saccharose. Analysis of the 16S rDNA sequences allowed strains CW-01 and CW-04 to be classified into the genus Desulfotomaculum. The corrosion speciality of the strains had been comparatively investigated. Especially SRB's growth curve, bearable oxygen capability, drug fastness and corrosion rate had been analyzed. The results showed that it is difficult to prevent bacterial corrosion caused by these two strains.

Autotrophic, hydrogen-oxidizing, denitrifying bacteria in groundwater, potential agents for bioremediation of nitrate contamination

USGS Publications Warehouse

Smith, R.L.; Ceazan, M.L.; Brooks, M.H.

1994-01-01

Addition of hydrogen or formate significantly enhanced the rate of consumption of nitrate in slurried core samples obtained from an active zone of denitrification in a nitrate-contaminated sand and gravel aquifer (Cape Cod, Mass.). Hydrogen uptake by the core material was immediate and rapid, with an apparent K(m) of 0.45 to 0.60 ??M and a V(max) of 18.7 nmol cm-3 h-1 at 30??C. Nine strains of hydrogen-oxidizing denitrifying bacteria were subsequently isolated from the aquifer. Eight of the strains grew autotrophically on hydrogen with either oxygen or nitrate as the electron acceptor. One strain grew mixotrophically. All of the isolates were capable of heterotrophic growth, but none were similar to Paracoccus denitrificans, a well-characterized hydrogen-oxidizing denitrifier. The kinetics for hydrogen uptake during denitrification were determined for each isolate with substrate depletion progress curves; the K(m)s ranged from 0.30 to 3.32 ??M, with V(max)s of 1.85 to 13.29 fmol cell-1 h-1. Because these organisms appear to be common constituents of the in situ population of the aquifer, produce innocuous end products, and could be manipulated to sequentially consume oxygen and then nitrate when both were present, these results suggest that these organisms may have significant potential for in situ bioremediation of nitrate contamination in groundwater.

Anaerobic Bacteria in Clinical Specimens – Frequent, But a Neglected Lot: A Five Year Experience at a Tertiary Care Hospital

PubMed Central

Shenoy, Padmaja Ananth; Gawda, Ashwini; Shetty, Seema; Anegundi, Renuka; Varma, Muralidhar; Mukhopadhyay, Chiranjay; Chawla, Kiran

2017-01-01

Introduction Anaerobic bacteria which constitute a significant proportion of the normal microbiota also cause variety of infections involving various anatomic sites. Considering the tedious culture techniques with longer turnaround time, anaerobic cultures are usually neglected by clinicians and microbiologists. Aim To study the frequency of isolation of different anaerobic bacteria from various clinical specimens. Materials and Methods A retrospective study to analyse the frequency of isolation of different anaerobic bacteria, was conducted over a period of five years from 2011 to 2015 including various clinical specimens submitted to anaerobic division of Microbiology laboratory. Anaerobic bacteria were isolated and identified following standard bacteriological techniques. Results Pathogenic anaerobes (n=336) were isolated from 278 (12.48%) of overall 2227 specimens processed with an average yield of 1.2 isolates. Anaerobes were isolated as polymicrobial flora with or without aerobic bacterial pathogens in 159 (57.2%) patients. Anaerobic Gram-negative bacilli (140, 41.7%) were the predominant isolates. B. fragilis group (67, 19.9%) were the most commonly isolated anaerobic pathogens. Anaerobes were predominantly isolated from deep seated abscess (23.9%). Conclusion Pathogenic anaerobes were isolated from various infection sites. Unless culture and susceptibility tests are performed as a routine, true magnitude of antimicrobial resistance among anaerobic pathogens will not be known. Knowledge of the distribution of these organisms may assist in the selection of appropriate empirical therapy for anaerobic infections. PMID:28892897

Pseudomonas putida F1 uses energy taxis to sense hydroxycinnamic acids

PubMed Central

Hughes, Jonathan G.; Zhang, Xiangsheng; Parales, Juanito V.; Ditty, Jayna L.; Parales, Rebecca E.

2017-01-01

Soil bacteria such as pseudomonads are widely studied due to their diverse metabolic capabilities, particularly the ability to degrade both naturally occurring and xenobiotic aromatic compounds. Chemotaxis, the directed movement of cells in response to chemical gradients, is common in motile soil bacteria and the wide range of chemicals detected often mirrors the metabolic diversity observed. Pseudomonas putida F1 is a soil isolate capable of chemotaxis toward, and degradation of, numerous aromatic compounds. We showed that P. putida F1 is capable of degrading members of a class of naturally occurring aromatic compounds known as hydroxycinnamic acids, which are components of lignin and are ubiquitous in the soil environment. We also demonstrated the ability of P. putida F1 to sense three hydroxycinnamic acids: p-coumaric, caffeic and ferulic acids. The chemotaxis response to hydroxycinnamic acids was induced during growth in the presence of hydroxycinnamic acids and was negatively regulated by HcaR, the repressor of the hydroxycinnamic acid catabolic genes. Chemotaxis to the three hydroxycinnamic acids was dependent on catabolism, as a mutant lacking the gene encoding feruloyl-CoA synthetase (Fcs), which catalyzes the first step in hydroxycinnamic acid degradation, was unable to respond chemotactically toward p-coumaric, caffeic, or ferulic acids. We tested whether an energy taxis mutant could detect hydroxycinnamic acids and determined that hydroxycinnamic acid sensing is mediated by the energy taxis receptor Aer2. PMID:28954643

A MEMBRANE FILTER PROCEDURE FOR ASSAYING CYTOTOXIC ACTIVITY IN HETEROTROPHIC BACTERIA ISOLATED FROM DRINKING WATER

EPA Science Inventory

Cytotoxic activity assays of Gram-negative, heterotrophic bacteria are often laborious and time consuming. The objective of this study was to develop in situ procedures for testing potential cytotoxic activities of heterotrophic bacteria isolated from drinking water systems. Wate...

Isolation and characterization of two novel ethanol-tolerant facultative-anaerobic thermophilic bacteria strains from waste compost.

PubMed

Fong, Jiunn C N; Svenson, Charles J; Nakasugi, Kenlee; Leong, Caine T C; Bowman, John P; Chen, Betty; Glenn, Dianne R; Neilan, Brett A; Rogers, Peter L

2006-10-01

In a search for potential ethanologens, waste compost was screened for ethanol-tolerant thermophilic microorganisms. Two thermophilic bacterial strains, M5EXG and M10EXG, with tolerance of 5 and 10% (v/v) ethanol, respectively, were isolated. Both isolates are facultative anaerobic, non-spore forming, non-motile, catalase-positive, oxidase-negative, Gram-negative rods that are capable of utilizing a range of carbon sources including arabinose, galactose, mannose, glucose and xylose and produce low amounts of ethanol, acetate and lactate. Growth of both isolates was observed in fully defined minimal media within the temperature range 50-80 degrees C and pH 6.0-8.0. Phylogenetic analysis of the 16S rDNA sequences revealed that both isolates clustered with members of subgroup 5 of the genus Bacillus. G+C contents and DNA-DNA relatedness of M5EXG and M10EXG revealed that they are strains belonging to Geobacillus thermoglucosidasius. However, physiological and biochemical differences were evident when isolates M5EXG and M10EXG were compared with G. thermoglucosidasius type strain (DSM 2542(T)). The new thermophilic, ethanol-tolerant strains of G. thermoglucosidasius may be candidates for ethanol production at elevated temperatures.

Antibacterial Activity of Lactic Acid Bacteria Isolated from Gastrointestinal Tract of “Ayam Kampung” Chicken Against Food Pathogens

NASA Astrophysics Data System (ADS)

Nur Jannah, Siti; Rini Saraswati, Tyas; Handayani, Dwi; Pujiyanto, Sri

2018-05-01

Food borne disease results from ingestion of water and wide variety of food contaminated with pathogenic organisms. The main causes of food borne diseases are bacteria, such as Escherichia coli and Staphylococcus aureus. The objective of this study was to determine antimicrobial activity of lactic acid bacteria (LAB) isolated from local chicken gastrointestinal tract with an emphasis on their probiotic properties. The colonies of bacteria that producing clear zone on MRSA plus 0.5% CaCO3, Gram-positive and catalase-negative were isolated as lactic acid bacteria. Some of the strains (10 isolates) were tested for their ability to inhibit growth of Escherichia coli and Staphylococcus aureus, and for acid pH and bile salt tolerance. The results showed that the all selected isolates producing antimicrobial compounds inhibits the growth of Escherichia coli and Staphylococcus aureus, both in the supernatant and supernatant plus 2M NaOH, and still growing in medium condition with pH 2.0 and 0.1% bile salt. It revealing the potential use of the lactic acid bacteria from chicken gastrointestinal tract for probiotics in food.

Rapid Identification of Bacteria in Positive Blood Culture Broths by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry▿

PubMed Central

Stevenson, Lindsay G.; Drake, Steven K.; Murray, Patrick R.

2010-01-01

Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry is a rapid, accurate method for identifying bacteria and fungi recovered on agar culture media. We report herein a method for the direct identification of bacteria in positive blood culture broths by MALDI-TOF mass spectrometry. A total of 212 positive cultures were examined, representing 32 genera and 60 species or groups. The identification of bacterial isolates by MALDI-TOF mass spectrometry was compared with biochemical testing, and discrepancies were resolved by gene sequencing. No identification (spectral score of <1.7) was obtained for 42 (19.8%) of the isolates, due most commonly to insufficient numbers of bacteria in the blood culture broth. Of the bacteria with a spectral score of ≥1.7, 162 (95.3%) of 170 isolates were correctly identified. All 8 isolates of Streptococcus mitis were misidentified as being Streptococcus pneumoniae isolates. This method provides a rapid, accurate, definitive identification of bacteria within 1 h of detection in positive blood cultures with the caveat that the identification of S. pneumoniae would have to be confirmed by an alternative test. PMID:19955282

Rapid identification of bacteria in positive blood culture broths by matrix-assisted laser desorption ionization-time of flight mass spectrometry.

PubMed

Stevenson, Lindsay G; Drake, Steven K; Murray, Patrick R

2010-02-01

Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry is a rapid, accurate method for identifying bacteria and fungi recovered on agar culture media. We report herein a method for the direct identification of bacteria in positive blood culture broths by MALDI-TOF mass spectrometry. A total of 212 positive cultures were examined, representing 32 genera and 60 species or groups. The identification of bacterial isolates by MALDI-TOF mass spectrometry was compared with biochemical testing, and discrepancies were resolved by gene sequencing. No identification (spectral score of < 1.7) was obtained for 42 (19.8%) of the isolates, due most commonly to insufficient numbers of bacteria in the blood culture broth. Of the bacteria with a spectral score of > or = 1.7, 162 (95.3%) of 170 isolates were correctly identified. All 8 isolates of Streptococcus mitis were misidentified as being Streptococcus pneumoniae isolates. This method provides a rapid, accurate, definitive identification of bacteria within 1 h of detection in positive blood cultures with the caveat that the identification of S. pneumoniae would have to be confirmed by an alternative test.

Long-Term Warming Alters Carbohydrate Degradation Potential in Temperate Forest Soils

DOE PAGES

Pold, Grace; Billings, Andrew F.; Blanchard, Jeff L.; ...

2016-09-02

As Earth's climate warms, soil carbon pools and the microbial communities that process them may change, altering the way in which carbon is recycled in soil. In this study, we used a combination of metagenomics and bacterial cultivation to evaluate the hypothesis that experimentally raising soil temperatures by 5°C for 5, 8, or 20 years increased the potential for temperate forest soil microbial communities to degrade carbohydrates. Warming decreased the proportion of carbohydrate-degrading genes in the organic horizon derived from eukaryotes and increased the fraction of genes in the mineral soil associated with Actinobacteria in all studies. Genes associated withmore » carbohydrate degradation increased in the organic horizon after 5 years of warming but had decreased in the organic horizon after warming the soil continuously for 20 years. However, a greater proportion of the 295 bacteria from 6 phyla (10 classes, 14 orders, and 34 families) isolated from heated plots in the 20-year experiment were able to depolymerize cellulose and xylan than bacterial isolates from control soils. Together, these findings indicate that the enrichment of bacteria capable of degrading carbohydrates could be important for accelerated carbon cycling in a warmer world.« less

Syntrophic co-culture of Bacillus subtilis and Klebsiella pneumonia for degradation of kraft lignin discharged from rayon grade pulp industry.

PubMed

Yadav, Sangeeta; Chandra, Ram

2015-07-01

In order to search the degradability of kraft lignin, the potential bacterial strains Bacillus subtilis (GU193980) and Klebsiella pneumoniae (GU193981) were isolated, screened and applied in axenic and co-culture conditions. Results revealed that mixed culture showed better decolorization efficiency (80%) and reduction of pollution parameters (COD 73% and BOD 62%) than axenic culture. This indicated syntrophic growth of these two bacteria rather than any antagonistic effect. The HPLC analysis of degraded samples of kraft lignin has shown the reduction in peak area compared to control, suggesting that decrease in color intensity might be largely attributed to the degradation of lignin by isolated bacteria. Further, the GC-MS analysis showed that most of the compounds detected in control were diminished after bacterial treatment. Further, the seed germination test using Phaseolus aureus has supported the detoxification of bacterial decolorized kraft lignin for environmental safety. All these observations have revealed that the developed bacterial co-culture was capable for the effective degradation and decolorization of lignin containing rayon grade pulp mill wastewater for environmental safety. Copyright © 2015. Published by Elsevier B.V.

Carbohydrate catabolic diversity of bifidobacteria and lactobacilli of human origin.

PubMed

McLaughlin, Heather P; Motherway, Mary O'Connell; Lakshminarayanan, Bhuvaneswari; Stanton, Catherine; Paul Ross, R; Brulc, Jennifer; Menon, Ravi; O'Toole, Paul W; van Sinderen, Douwe

2015-06-16

Because increased proportions of particular commensal bacteria such as bifidobacteria and lactobacilli have been linked to human health through a variety of mechanisms, there is corresponding interest in identifying carbohydrates that promote growth and metabolic activity of these bacteria. We evaluated the ability of 20 carbohydrates, including several commercially available carbohydrates that are sold as prebiotic ingredients, to support growth of 32 human-derived isolates belonging to the genera Bifidobacterium and Lactobacillus, including those isolated from healthy elderly subjects. In general, bifidobacterial strains were shown to display more diverse carbohydrate utilization profiles compared to the tested Lactobacillus species, with several bifidobacterial strains capable of metabolizing xylo-oligosaccharide (XOS), arabinoxylan, maltodextrin, galactan and carbohydrates containing fructo-oligosaccharide (FOS) components. In contrast, maltodextrin, galactan, arabinogalactan and galactomannan did not support robust growth (≥0.8 OD600 nm) of any of the Lactobacillus strains assessed. Carbohydrate fermentation was variable among strains tested of the same species for both genera. This study advances our knowledge of polysaccharide utilization by human gut commensals, and provides information for the rational design of selective prebiotic food ingredients. Copyright © 2015 Elsevier B.V. All rights reserved.

New methods for isolation of keratolytic bacteria inducing intractable hoof wall cavity (Gidoh) in a horse; double screening procedures of the horn powder agar-translucency test and horn zymography

PubMed Central

KUWANO, Atsutoshi; NIWA, Hidekazu; ARAI, Katsuhiko

2017-01-01

ABSTRACT To establish a new system to isolate keratolytic bacteria from the hoof wall cavity (Gidoh) of a racehorse, we invented the horn powder agar-translucency (HoPAT) test and horn zymography (HZ). Using routine bacteriological techniques and these methods, we isolated five strains of keratolytic soil bacteria, which were then identified by means of 16S ribosomal RNA (rRNA) gene sequencing analysis. The findings from the study on the horse suggested that Brevibacterium luteolum played the main role in the local fragility of the hoof, eventually forming a Gidoh in coordination with four other strains of keratolytic bacteria. The double screening procedures of the HoPAT test and HZ were useful and easy techniques for isolating the keratolytic bacteria from the horn lesions. PMID:28400703

Lactic Acid Bacteria Producing Inhibitor of Alpha Glucosidase Isolated from Ganyong (Canna Edulis) and Kimpul (Xanthosoma sagittifolium)

NASA Astrophysics Data System (ADS)

Nurhayati, Rifa; Miftakhussolikhah; Frediansyah, Andri; Lailatul Rachmah, Desy

2017-12-01

Type 2 diabetes is a disease that caused by the failure of insulin secretion by the beta cells of the pancreas and insulin resistance in peripheral levels. One therapy for diabetics is by inhibiting the activity of α-glucosidase. Lactic acid bacteria have the ability to inhibit of α-glucosidase activity. The aims of this research was to isolation and screening of lactic acid bacteria from ganyong tuber (Canna Edulis) and kimpul tuber (Xanthosoma sagittifolium), which has the ability to inhibit the activity of α-glucosidase. Eightteen isolates were identified as lactic acid bacteria and all of them could inhibit the activity of α-glukosidase. The GN 8 isolate was perform the highest inhibition acivity.

Simultaneous isolation of anaerobic bacteria from udder abscesses and mastitic milk in lactating dairy cows.

PubMed

Greeff, A S; du Preez, J H

1985-12-01

A variety of non-sporulating anaerobic bacterial species were isolated from udder abscesses in 10 lactating dairy cows. Fifty percent of the abscesses yielded multiple anaerobic species and the other 50% only 1 species. The anaerobic bacteria, however, were always accompanied by classical facultative anaerobic mastitogenic bacteria. In four of the five cows also afflicted with mastitis in the quarters with abscesses, the anaerobic and facultative anaerobic bacteria were identical. Peptococcus indolicus was the most commonly isolated organism followed by Eubacterium and Bacteroides spp. Bacteroides fragilis was resistant to penicillin, ampicillin and tetracycline.

Enzyme activity screening of thermophilic bacteria isolated from Dusun Tua Hot Spring, Malaysia

NASA Astrophysics Data System (ADS)

Msarah, Marwan; Ibrahim, Izyanti; Aqma, Wan Syaidatul

2018-04-01

Thermophilic bacteria have biotechnological importance due to the availability of unique enzymes which are stable in extreme circumstances. The aim of this study includes to isolate thermophilic bacteria from hot spring and screen for important enzyme activities. Water samples from the Dusun Tua Hot Spring were collected and the physiochemical characterisation of water was measured. Eight thermophilic bacteria were isolated and determined to have at least three strong enzyme activity including protease, lipase, amylase, cellulase, pectinase and xylanase. The results showed that HuluC2 displayed all the enzyme activities and can be further studied.

Antibacterial Activity of the Isolation Ethyl Acetate-Soluble Extract Noni Fruit (Morindra citrifolia L.) against Meat Bacterial Decay

NASA Astrophysics Data System (ADS)

Nugraheni, E. R.; Nurrakhman, M. B. E.; Munawaroh, H.; Saputri, L.

2017-02-01

Noni (Morindra citrifolia L.) is native to Indonesia which have medicinal properties. One of them as an antibacterial. This study aims to determine the antibacterial activity of isolates from the ethanol extract noni fruit to bacterial decay meat is Bacillus licheniformis, Klebsiella pneumonia, Bacillus alvei, Acinetobacter calcoaceticus, and Staphylococcus saprophyticus. The extraction process using the maceration method, and then made a partition by centrifugation ethyl acetate. Soluble part partition showed bacterial growth inhibition activity of the strong to very strong. Furthermore, the ethyl acetate soluble partition on preparative thin layer chromatography produced 5 isolates. Isolates obtained antibacterial activity test performed with a concentration of 20% and 30%. The results of antibacterial test against bacteria test isolates, showing isolates A can not inhibit the growth of bacteria, isolates B and C have medium activity and strong, isolates D and E isolates have activity against bacteria that were tested. MIC and MBC test results showed that the isolates B gives an inhibitory effect (bacteriostatic) against all bacteria. Content analysis of compounds by TLC using the reagents cerium (IV) sulfate indicates a phenol group. Isolates B contains a major compound which can be used as an antibacterial candidate in food preservation replace chemical preservatives.

Incidence of carbapenem-resistant gram negatives in Italian transplant recipients: a nationwide surveillance study.

PubMed

Lanini, Simone; Costa, Alessandro Nanni; Puro, Vincenzo; Procaccio, Francesco; Grossi, Paolo Antonio; Vespasiano, Francesca; Ricci, Andrea; Vesconi, Sergio; Ison, Michael G; Carmeli, Yehuda; Ippolito, Giuseppe

2015-01-01

Bacterial infections remain a challenge to solid organ transplantation. Due to the alarming spread of carbapenem-resistant gram negative bacteria, these organisms have been frequently recognized as cause of severe infections in solid organ transplant recipients. Between 15 May and 30 September 2012 we enrolled 887 solid organ transplant recipients in Italy with the aim to describe the epidemiology of gram negative bacteria spreading, to explore potential risk factors and to assess the effect of early isolation of gram negative bacteria on recipients' mortality during the first 90 days after transplantation. During the study period 185 clinical isolates of gram negative bacteria were reported, for an incidence of 2.39 per 1000 recipient-days. Positive cultures for gram negative bacteria occurred early after transplantation (median time 26 days; incidence rate 4.33, 1.67 and 1.14 per 1,000 recipient-days in the first, second and third month after SOT, respectively). Forty-nine of these clinical isolates were due to carbapenem-resistant gram negative bacteria (26.5%; incidence 0.63 per 1000 recipient-days). Carbapenems resistance was particularly frequent among Klebsiella spp. isolates (49.1%). Recipients with longer hospital stay and those who received either heart or lung graft were at the highest risk of testing positive for any gram negative bacteria. Moreover recipients with longer hospital stay, lung recipients and those admitted to hospital for more than 48h before transplantation had the highest probability to have culture(s) positive for carbapenem-resistant gram negative bacteria. Forty-four organ recipients died (0.57 per 1000 recipient-days) during the study period. Recipients with at least one positive culture for carbapenem-resistant gram negative bacteria had a 10.23-fold higher mortality rate than those who did not. The isolation of gram-negative bacteria is most frequent among recipient with hospital stays >48 hours prior to transplant and in those receiving either heart or lung transplants. Carbapenem-resistant gram negative isolates are associated with significant mortality.

Phylogenetic multilocus sequence analysis of indigenous slow-growing rhizobia nodulating cowpea (Vigna unguiculata L.) in Greece.

PubMed

Tampakaki, Anastasia P; Fotiadis, Christos T; Ntatsi, Georgia; Savvas, Dimitrios

2017-04-01

Cowpea (Vigna unguiculata) is a promiscuous grain legume, capable of establishing efficient symbiosis with diverse symbiotic bacteria, mainly slow-growing rhizobial species belonging to the genus Bradyrhizobium. Although much research has been done on cowpea-nodulating bacteria in various countries around the world, little is known about the genetic and symbiotic diversity of indigenous cowpea rhizobia in European soils. In the present study, the genetic and symbiotic diversity of indigenous rhizobia isolated from field-grown cowpea nodules in three geographically different Greek regions were studied. Forty-five authenticated strains were subjected to a polyphasic approach. ERIC-PCR based fingerprinting analysis grouped the isolates into seven groups and representative strains of each group were further analyzed. The analysis of the rrs gene showed that the strains belong to different species of the genus Bradyrhizobium. The analysis of the 16S-23S IGS region showed that the strains from each geographic region were characterized by distinct IGS types which may represent novel phylogenetic lineages, closely related to the type species of Bradyrhizobium pachyrhizi, Bradyrhizobium ferriligni and Bradyrhizobium liaoningense. MLSA analysis of three housekeeping genes (recA, glnII, and gyrB) showed the close relatedness of our strains with B. pachyrhizi PAC48 T and B. liaoningense USDA 3622 T and confirmed that the B. liaoningense-related isolate VUEP21 may constitute a novel species within Bradyrhizobium. Moreover, symbiotic gene phylogenies, based on nodC and nifH genes, showed that the B. pachyrhizi-related isolates belonged to symbiovar vignae, whereas the B. liaoningense-related isolates may represent a novel symbiovar. Copyright © 2017 Elsevier GmbH. All rights reserved.

Microbiological oxidation of antimony(III) with oxygen or nitrate by bacteria isolated from contaminated mine sediments

USGS Publications Warehouse

Terry, Lee R.; Kulp, Thomas R.; Wiatrowski, Heather A.; Miller, Laurence G.; Oremland, Ronald S.

2015-01-01

Bacterial oxidation of arsenite [As(III)] is a well-studied and important biogeochemical pathway that directly influences the mobility and toxicity of arsenic in the environment. In contrast, little is known about microbiological oxidation of the chemically similar anion antimonite [Sb(III)]. In this study, two bacterial strains, designated IDSBO-1 and IDSBO-4, which grow on tartrate compounds and oxidize Sb(III) using either oxygen or nitrate, respectively, as a terminal electron acceptor, were isolated from contaminated mine sediments. Both isolates belonged to the Comamonadaceae family and were 99% similar to previously described species. We identify these novel strains as Hydrogenophagataeniospiralis strain IDSBO-1 and Variovorax paradoxus strain IDSBO-4. Both strains possess a gene with homology to the aioA gene, which encodes an As(III)-oxidase, and both oxidize As(III) aerobically, but only IDSBO-4 oxidized Sb(III) in the presence of air, while strain IDSBO-1 could achieve this via nitrate respiration. Our results suggest that expression of aioA is not induced by Sb(III) but may be involved in Sb(III) oxidation along with an Sb(III)-specific pathway. Phylogenetic analysis of proteins encoded by the aioA genes revealed a close sequence similarity (90%) among the two isolates and other known As(III)-oxidizing bacteria, particularly Acidovorax sp. strain NO1. Both isolates were capable of chemolithoautotrophic growth using As(III) as a primary electron donor, and strain IDSBO-4 exhibited incorporation of radiolabeled [14C]bicarbonate while oxidizing Sb(III) from Sb(III)-tartrate, suggesting possible Sb(III)-dependent autotrophy. Enrichment cultures produced the Sb(V) oxide mineral mopungite and lesser amounts of Sb(III)-bearing senarmontite as precipitates.

Culturable Heavy Metal-Resistant and Plant Growth Promoting Bacteria in V-Ti Magnetite Mine Tailing Soil from Panzhihua, China

PubMed Central

Zhang, Chu; Liu, Huiying; Liu, Jin; Zheng, Wenwen; Kang, Xia; Leng, Xuejun; Zhao, Ke; Gu, Yunfu; Zhang, Xiaoping; Xiang, Quanju; Chen, Qiang

2014-01-01

To provide a basis for using indigenous bacteria for bioremediation of heavy metal contaminated soil, the heavy metal resistance and plant growth-promoting activity of 136 isolates from V-Ti magnetite mine tailing soil were systematically analyzed. Among the 13 identified bacterial genera, the most abundant genus was Bacillus (79 isolates) out of which 32 represented B. subtilis and 14 B. pumilus, followed by Rhizobium sp. (29 isolates) and Ochrobactrum intermedium (13 isolates). Altogether 93 isolates tolerated the highest concentration (1000 mg kg−1) of at least one of the six tested heavy metals. Five strains were tolerant against all the tested heavy metals, 71 strains tolerated 1,000 mg kg−1 cadmium whereas only one strain tolerated 1,000 mg kg−1 cobalt. Altogether 67% of the bacteria produced indoleacetic acid (IAA), a plant growth-promoting phytohormone. The concentration of IAA produced by 53 isolates was higher than 20 µg ml−1. In total 21% of the bacteria produced siderophore (5.50–167.67 µg ml−1) with two Bacillus sp. producing more than 100 µg ml−1. Eighteen isolates produced both IAA and siderophore. The results suggested that the indigenous bacteria in the soil have beneficial characteristics for remediating the contaminated mine tailing soil. PMID:25188470

Susceptibility of Caenorhabditis elegans to Burkholderia Infection Depends on Prior Diet and Secreted Bacterial Attractants

PubMed Central

Cooper, Vaughn S.; Carlson, Wendy A.; LiPuma, John J.

2009-01-01

The nematode Caenorhabditis elegans may be killed by certain pathogenic bacteria and thus is a model organism for studying interactions between bacteria and animal hosts. However, growing nematodes on prey bacteria may influence their susceptibility to potential pathogens. A method of axenic nematode culture was developed to isolate and quantify interactions between C. elegans and potentially pathogenic strains of the Burkholderia cepacia complex. Studying these dynamics in liquid solution rather than on agar surfaces minimized nematode avoidance behavior and resolved more differences among isolates. Most isolates of B. cenocepacia, B. ambifaria and B. cepacia caused 60–80% mortality of nematodes after 7 days, whereas isolates of B. multivorans caused less mortality (<25%) and supported nematode reproduction. However, some B. cenocepacia isolates recovered from chronic infections were much less virulent (5–28% mortality). As predicted, prior diet altered the outcome of interactions between nematodes and bacteria. When given the choice between Burkholderia and E. coli as prey on agar, axenically raised nematodes initially preferred most lethal Burkholderia isolates to E. coli as a food source, but this was not the case for nematodes fed E. coli, which avoided toxic Burkholderia. This food preference was associated with the cell-free supernatant and thus secreted compounds likely mediated bacterial-nematode interactions. This model, which isolates interactions between bacteria and nematodes from the effects of prior feeding, demonstrates that bacteria can influence nematode behavior and their susceptibility to pathogens. PMID:19956737

[Pigments of green sulfur bacteria isolated from reservoirs of Iavoriv sulfur deposit].

PubMed

Baran, I M; Hudz', S P; Hnatush, S O; Fedorovych, A M

2004-01-01

The enormous amount of hydrogen sulfide (up to 11 mg/ml) is present in the Yavoriv sulfur deposit reservoirs owing to sulfur reductive bacteria activity. As a consequence the ecological situation is badly affected and requires recovering. The biological H2S decomposition by photosynthetic sulfur bacteria, which use the hydrogen sulfide as electron donor during photosynthesis, can be one of the possible ways of this toxic substance destruction. The qualitative and quantitative analysis of photosynthetic pigments composition that derived from green photosynthesizing sulfur bacteria from reservoirs of Yavoriv sulfur deposit is carried out. It was fixed that Pelodictyon sp., Chlorobium sp. and isolated consortia "Pelochromatium sp." contain the bacteriochlorophyll c and d. All the isolated cultures contained bacteriochlorophyll a in trace amounts. The obtained photosynthetic pigments (bacteriochlorophylls, carotenoids) were recognized by their absorption spectra in the visible and far-red region and by their quantity. The difference was not essential. All investigated cultures of isolated bacteria contain some carotenoid the Chlorobium sp. and obtained consortia possesses isorenieratene. The absorption maxima of extracted pigments from young cultures of isolated green sulfur bacteria are more definitely displayed than those from old cultures. Investigations of phototrophic sulfur bacteria were carried out in Ukraine up to now. Ecological problem that occurred in the Yavoriv sulfur deposit as a result of the deposit exploitation caused a necessity of the investigation of photosynthetic sulfur bacteria and bacterial photosynthesis mechanism. The photosynthetic pigments nature identification will promote the fast and precise identification of the new forms of photosynthetic sulfur bacteria and will extend our knowledge about their role in the anoxygenic photosynthesis.

Frequency of Resistance and Susceptible Bacteria Isolated from Houseflies

PubMed Central

Davari, B; Kalantar, E; Zahirnia, A; Moosa-Kazemi, SH

2010-01-01

Background: In this study, we determine the vector competence of Musca domestica with reference to the transmission of susceptible and resistance bacterial strains in hospitals and slaughter house in Sanandaj City, west Iran. Methods: Totally 908 houseflies were collected to isolate bacteria from their external body based on standard procedures.Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method on Mueller Hinton agar based on recommendations of CLSI (formerly the National Committee for Clinical Laboratory Standards). Results: From collected houseflies, 366 bacteria species were isolated. The most common isolated bacterium at hospitals was Klebsiella pneumoniae 43.3% (n= 90) followed by Pseudomonas aeruginosa 37% (n= 77), while that of slaughterhouse was Proteus mirabilis. 29.1% (n= 46) followed by Citrobacter freundii 28.4% (n= 45). Among all the isolates from hospitals, cephalexin, chloramphenicol, ampicillin, and tetracycline, resistance rates were above 32.5% and gentamicin expressed the highest susceptibility among all the isolates from hospitals. It is worth to note that K. pneumoniae showed 61% and 44.5% resistance to cephalexin and chloramphenicol respectively. Similarly, all isolates from slaughterhouse were more than 28% and 30% resistant to cephalexin and chloramphenicol respectively. Surprisingly, among all the isolates, Citrobacter freundii were highly resistant to gentamicin. Conclusion: Houseflies collected from hospitals and slaughterhouse may be involved in the spread of drug resistant bacteria and may increase the potential of human exposure to drug resistant bacteria. PMID:22808400

Frequency of resistance and susceptible bacteria isolated from houseflies.

PubMed

Davari, B; Kalantar, E; Zahirnia, A; Moosa-Kazemi, Sh

2010-01-01

In this study, we determine the vector competence of Musca domestica with reference to the transmission of susceptible and resistance bacterial strains in hospitals and slaughter house in Sanandaj City, west Iran. Totally 908 houseflies were collected to isolate bacteria from their external body based on standard procedures.Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method on Mueller Hinton agar based on recommendations of CLSI (formerly the National Committee for Clinical Laboratory Standards). From collected houseflies, 366 bacteria species were isolated. The most common isolated bacterium at hospitals was Klebsiella pneumoniae 43.3% (n= 90) followed by Pseudomonas aeruginosa 37% (n= 77), while that of slaughterhouse was Proteus mirabilis. 29.1% (n= 46) followed by Citrobacter freundii 28.4% (n= 45). Among all the isolates from hospitals, cephalexin, chloramphenicol, ampicillin, and tetracycline, resistance rates were above 32.5% and gentamicin expressed the highest susceptibility among all the isolates from hospitals. It is worth to note that K. pneumoniae showed 61% and 44.5% resistance to cephalexin and chloramphenicol respectively. Similarly, all isolates from slaughterhouse were more than 28% and 30% resistant to cephalexin and chloramphenicol respectively. Surprisingly, among all the isolates, Citrobacter freundii were highly resistant to gentamicin. Houseflies collected from hospitals and slaughterhouse may be involved in the spread of drug resistant bacteria and may increase the potential of human exposure to drug resistant bacteria.

Microbial enhanced heavy crude oil recovery through biodegradation using bacterial isolates from an Omani oil field.

PubMed

Al-Sayegh, Abdullah; Al-Wahaibi, Yahya; Al-Bahry, Saif; Elshafie, Abdulkadir; Al-Bemani, Ali; Joshi, Sanket

2015-09-16

Biodegradation is a cheap and environmentally friendly process that could breakdown and utilizes heavy crude oil (HCO) resources. Numerous bacteria are able to grow using hydrocarbons as a carbon source; however, bacteria that are able to grow using HCO hydrocarbons are limited. In this study, HCO degrading bacteria were isolated from an Omani heavy crude oil field. They were then identified and assessed for their biodegradation and biotransformation abilities under aerobic and anaerobic conditions. Bacteria were grown in five different minimum salts media. The isolates were identified by MALDI biotyper and 16S rRNA sequencing. The nucleotide sequences were submitted to GenBank (NCBI) database. The bacteria were identified as Bacillus subtilis and B. licheniformis. To assess microbial growth and biodegradation of HCO by well-assay on agar plates, samples were collected at different intervals. The HCO biodegradation and biotransformation were determined using GC-FID, which showed direct correlation of microbial growth with an increased biotransformation of light hydrocarbons (C12 and C14). Among the isolates, B. licheniformis AS5 was the most efficient isolate in biodegradation and biotransformation of the HCO. Therefore, isolate AS5 was used for heavy crude oil recovery experiments, in core flooding experiments using Berea core plugs, where an additional 16 % of oil initially in place was recovered. This is the first report from Oman for bacteria isolated from an oil field that were able to degrade and transform HCO to lighter components, illustrating the potential use in HCO recovery. The data suggested that biodegradation and biotransformation processes may lead to additional oil recovery from heavy oil fields, if bacteria are grown in suitable medium under optimum growth conditions.

Utility of 16S rDNA Sequencing for Identification of Rare Pathogenic Bacteria.

PubMed

Loong, Shih Keng; Khor, Chee Sieng; Jafar, Faizatul Lela; AbuBakar, Sazaly

2016-11-01

Phenotypic identification systems are established methods for laboratory identification of bacteria causing human infections. Here, the utility of phenotypic identification systems was compared against 16S rDNA identification method on clinical isolates obtained during a 5-year study period, with special emphasis on isolates that gave unsatisfactory identification. One hundred and eighty-seven clinical bacteria isolates were tested with commercial phenotypic identification systems and 16S rDNA sequencing. Isolate identities determined using phenotypic identification systems and 16S rDNA sequencing were compared for similarity at genus and species level, with 16S rDNA sequencing as the reference method. Phenotypic identification systems identified ~46% (86/187) of the isolates with identity similar to that identified using 16S rDNA sequencing. Approximately 39% (73/187) and ~15% (28/187) of the isolates showed different genus identity and could not be identified using the phenotypic identification systems, respectively. Both methods succeeded in determining the species identities of 55 isolates; however, only ~69% (38/55) of the isolates matched at species level. 16S rDNA sequencing could not determine the species of ~20% (37/187) of the isolates. The 16S rDNA sequencing is a useful method over the phenotypic identification systems for the identification of rare and difficult to identify bacteria species. The 16S rDNA sequencing method, however, does have limitation for species-level identification of some bacteria highlighting the need for better bacterial pathogen identification tools. © 2016 Wiley Periodicals, Inc.

Azospirillum brasilense, a Beneficial Soil Bacterium: Isolation and Cultivation.

PubMed

Alexandre, Gladys

2017-11-09

Bacteria of the genus Azospirillum comprise 15 species to date, with A. brasilense the best studied species in the genus. Azospirillum are soil bacteria able to promote the growth of plants from 113 species spanning 35 botanical families. These non-pathogenic and beneficial bacteria are ubiquitous in soils and inhabit the roots of diverse plants. These bacteria are microaerophilic, able to fix nitrogen under free-living conditions, motile, and able to navigate in gradients of various chemicals, including oxygen. These physiological traits are used to isolate these soil bacteria from soil and plant root samples, providing isolates that can be used for studying microbial physiology and plant growth promotion. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

Preferential Promotion of Lycopersicon esculentum (Tomato) Growth by Plant Growth Promoting Bacteria Associated with Tomato.

PubMed

Vaikuntapu, Papa Rao; Dutta, Swarnalee; Samudrala, Ram Babu; Rao, Vukanti R V N; Kalam, Sadaf; Podile, Appa Rao

2014-12-01

A total of 74 morphologically distinct bacterial colonies were selected during isolation of bacteria from different parts of tomato plant (rhizoplane, phylloplane and rhizosphere) as well as nearby bulk soil. The isolates were screened for plant growth promoting (PGP) traits such as production of indole acetic acid, siderophore, chitinase and hydrogen cyanide as well as phosphate solubilization. Seven isolates viz., NR4, NR6, RP3, PP1, RS4, RP6 and NR1 that exhibited multiple PGP traits were identified, based on morphological, biochemical and 16S rRNA gene sequence analysis, as species that belonged to four genera Aeromonas, Pseudomonas, Bacillus and Enterobacter. All the seven isolates were positive for 1-aminocyclopropane-1-carboxylate deaminase. Isolate NR6 was antagonistic to Fusarium solani and Fusarium moniliforme, and both PP1 and RP6 isolates were antagonistic to F. moniliforme. Except RP6, all isolates adhered significantly to glass surface suggestive of biofilm formation. Seed bacterization of tomato, groundnut, sorghum and chickpea with the seven bacterial isolates resulted in varied growth response in laboratory assay on half strength Murashige and Skoog medium. Most of the tomato isolates positively influenced tomato growth. The growth response was either neutral or negative with groundnut, sorghum and chickpea. Overall, the results suggested that bacteria with PGP traits do not positively influence the growth of all plants, and certain PGP bacteria may exhibit host-specificity. Among the isolates that positively influenced growth of tomato (NR1, RP3, PP1, RS4 and RP6) only RS4 was isolated from tomato rhizosphere. Therefore, the best PGP bacteria can also be isolated from zones other than rhizosphere or rhizoplane of a plant.

Isolation of carbohydrate-metabolizing, extremely halophilic bacteria.

NASA Technical Reports Server (NTRS)

Tomlinson, G. A.; Hochstein, L. I.

1972-01-01

Four previously unrecognized strains of extremely halophilic bacteria that utilize carbohydrates have been isolated. Gas production proved an unreliable index of carbohydrate metabolism; therefore, carbohydrate utilization was measured by determining acid formation and sugar disappearance during growth. By these procedures, carbohydrate utilization was readily detected. The results suggest that carbohydrate dissimilation by extremely halophilic bacteria may be more common than previously thought and that the apparent rarity of carbohydrate-metabolizing halophiles may be an artifact of the isolation procedures used.

Analysis of 16S rRNA gene lactic acid bacteria (LAB) isolate from Markisa fruit (Passiflora sp.) as a producer of protease enzyme and probiotics

NASA Astrophysics Data System (ADS)

Hidayat, Habibi

2017-03-01

16S rRNA gene analysis of bacteria lactic acid (LAB) isolate from Markisa Kuning Fruit (Passiflora edulis var. flavicarpa) as a producer of protease enzyme and probiotics has been done. The aim of the study is to determine the protease enzyme activity and 16S rRNA gene amplification using PCR. The calculation procedure was done to M4 isolate bacteria lactic acid (LAB) Isolate which has been resistant to acids with pH 2.0 in the manner of screening protease enzyme activity test result 6.5 to clear zone is 13 mm againts colony diametre is 2 mm. The results of study enzyme activity used spectrophotometer UV-Vis obtainable the regression equation Y=0.02983+0.001312X, with levels of protein M4 isolate is 0.6594 mg/mL and enzyme activity of obtainable is 0.8626 unit/ml while the spesific enzyme activity produced is 1.308 unit/mg. Then, 16S rRNA gene amplificatiom and DNA sequencing has been done. The results of study showed that the bacteria species contained from M4 bacteria lactic acid (LAB) isolate is Weisella cibiria strain II-I-59. Weisella cibiria strain II-I-59 is one of bacteria could be utilized in the digestive tract.

Plasmid incidence in bacteria from deep subsurface sediments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fredrickson, J.K.; Hicks, R.J.; Li, S.W.

Bacteria were isolated from deep terrestrial subsurface sediments underlying the coastal plain of South Carolina. A total of 163 isolates from deep sediments, surface soil, and return drill muds were examined for plasmid DNA content and resistance to the antibiotics penicillin, ampicillin, carbenicillin, streptomycin, kanamycin, and tetracycline. MICs of Cu{sup 2+}, Cr{sup 3+}, and Hg{sup 2+} for each isolate were also determined. The overall frequency of plasmid occurrence in the subsurface bacteria was 33%. Resistance was most frequent to penicillin (70% of all isolates), ampicillin (49%), and carbenicillin (32%) and was concluded to be related to the concentrations of themore » individual antibiotics in the disks used for assaying resistance and to the production of low levels of {beta}-lactamase. The frequencies of resistance to penicillin and ampicillin were significantly greater for isolates bearing plasmids than for plasmidless isolates; however, resistance was not transferable to penicillin-sensitive Escherichia coli. Hybridization of subsurface bacterial plasmids and chromosomal DNA with a whole-TOL-plasmid (pWWO) probe revealed some homology of subsurface bacterial plasmid and chromosomal DNAs, indicating a potential for those bacterial to harbor catabolic genes on plasmids or chromosomes. The incidences of antibiotic resistance and MICs of metals for subsurface bacteria were significantly different from those drill mud bacteria, ruling out the possibility that bacteria from sediments were derived from drill muds.« less

Substrate-induced growth and isolation of Acidobacteria from acidic Sphagnum peat.

PubMed

Pankratov, Timofei A; Serkebaeva, Yulia M; Kulichevskaya, Irina S; Liesack, Werner; Dedysh, Svetlana N

2008-05-01

Fluorescence in situ hybridization (FISH) was applied to estimate the population size of the poorly characterized phylum Acidobacteria in acidic peat sampled from nine different Sphagnum-dominated wetlands of Northern Russia. The cell numbers of these bacteria in oxic peat layers ranged from 0.4 x 10(6) to 1.3 x 10(7) cells per g of wet peat, comprising up to 4% of total bacterial cells. Substrate-induced growth of acidobacteria was observed after amendment of peat samples with glucose, pectin, xylan, starch, ethanol and methanol, while weak or no response was obtained for acetate, pyruvate, mannitol and cellobiose. Using low-nutrient media and FISH-mediated monitoring of the isolation procedure, we succeeded in obtaining nine strains of acidobacteria in pure cultures. These strains belonged to subdivisions 1 and 3 of the Acidobacteria and represented strictly aerobic, heterotrophic organisms. Except for methanol, the substrate utilization patterns of these isolates matched the results obtained in our substrate-amendment experiments with native peat. All strains were also capable of utilizing galacturonic acid, a characteristic component of the cell wall in Sphagnum spp, which is released during moss decomposition. Most isolates from subdivision 1 were truly acidophilic organisms with the growth optimum at pH 3.5-4.5, while the isolates from subdivision 3 grew optimally at pH 5.5-6.5. Another important phenotypic trait of novel strains was their capability of active growth at low temperatures. Both acidophily and low-temperature growth are consistent with the occurrence of acidobacteria in cold and acidic northern wetlands.

Microbial pollution indicators and culturable heterotrophic bacteria in a Mediterranean area (Southern Adriatic Sea Italian coasts)

NASA Astrophysics Data System (ADS)

Stabili, L.; Cavallo, R. A.

2011-05-01

In the present study we evaluated the degree of microbial water pollution along the coast line between Brindisi and Santa Maria di Leuca (Southern Adriatic Sea) as well as the culturable heterotrophic bacteria abundances and biodiversity in relation to the microbiological quality of the water. A total of 3773 colonies were isolated, subcultured and identified by several morphological, cultural and biochemical methods including the standardized API 20 E and API 20 NE tests. Along the examined coastal tract the microbial pollution indicators were always below the tolerance limits for bathing waters defined by the CEE directive, suggesting a good sanitary quality. Concerning culturable heterotrophic bacteria, different temporal density trends were observed in the four sites in relation to their geographical position. A positive relationship between the bacterial abundances and the temperature was observed in S. Cataldo and Otranto. The culturable bacterial community was mainly composed of the genera Aeromonas, Pseudomonas, Photobacterium and Flavobacterium. The Enterobacteriaceae family represented a conspicuous component of the bacterial community too. Bacilli were predominant among the Gram-positive bacteria. Of interest is the isolation of yeasts (2% at the surface and 1% at the bottom) taking into account their capability of biodegradation of various materials. Because of the low level of microbial pollution recorded, our results are indicative of the natural variation and diversity of the culturable bacterial community in such an oligotrophic ecosystem and could represent a good point of comparison with other ecosystems as well as a baseline for long term studies aimed to evaluate the effects of environmental fluctuations and human impacts on this aspect of biodiversity in coastal areas.

Paraformaldehyde-Resistant Starch-Fermenting Bacteria in “Starch-Base” Drilling Mud

PubMed Central

Myers, G. E.

1962-01-01

Starch-fermenting bacteria were found in each of 12 samples of nonfermenting starch-base drilling mud examined. Of the 12 samples, 3 contained very active starch-fermenting gram-positive spore-bearing bacilli closely resembling Bacillus subtilis. Similar active starch-fermenting bacteria were found in fermenting starch-base drilling mud and in corn starch and slough water used to prepare such mud. The active starch-fermenting microorganisms completely hydrolyzed 1% (w/v) corn starch within 24 hr at 37.5 C. The active starch-fermenting bacteria isolated from fermenting drilling mud were capable of surviving 12 hr of continuous exposure to 0.1% (w/w) paraformaldehyde or 1 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, with no diminution in starch-fermenting ability. The same organisms fermented starch after 3 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, but not after 4 hr of exposure. The phenomenon of rapid disappearance of paraformaldehyde from fermenting drilling mud was observed in the laboratory using a modified sodium sulfite test. Paraformaldehyde, initially present in a concentration of 0.192 lb per barrel of mud, completely disappeared in 9 hr at 22 to 23 C. A significant decrease in paraformaldehyde concentration was detected 0.5 hr after preparation of the mud. It is suggested that the presence of relatively high concentrations of ammonia and chloride in the mud may facilitate the disappearance of paraformaldehyde. The failure of 0.1% (w/w) paraformaldehyde to inhibit the strong starch-fermenting microorganisms isolated from fermenting drilling mud, and the rapid disappearance of paraformaldehyde from the mud, explains the fermentation of starch which occurred in this mud, despite the addition of paraformaldehyde. PMID:13936949

Phenotypic and Genotypic Characterization of Some Lactic Acid Bacteria Isolated from Bee Pollen: A Preliminary Study

PubMed Central

BELHADJ, Hani; HARZALLAH, Daoud; BOUAMRA, Dalila; KHENNOUF, Seddik; Dahamna, Saliha; GHADBANE, Mouloud

2014-01-01

In the present work, five hundred and sixty-seven isolates of lactic acid bacteria were recovered from raw bee pollen grains. All isolates were screened for their antagonistic activity against both Gram-positive and Gram-negative pathogenic bacteria. Neutralized supernatants of 54 lactic acid bacteria (LAB) cultures from 216 active isolates inhibited the growth of indicator bacteria. They were phenotypically characterized, based on the fermentation of 39 carbohydrates. Using the simple matching coefficient and unweighted pair group algorithm with arithmetic averages (UPGMA), seven clusters with other two members were defined at the 79% similarity level. The following species were characterized: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Pediococcus acidilactici, Pediococcus pentosaceus, and unidentified lactobacilli. Phenotypic characteristics of major and minor clusters were also identified. Partial sequencing of the 16S rRNA gene of representative isolates from each cluster was performed, and ten strains were assigned to seven species: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Lactobacillus ingluviei, Pediococcus pentosaceus, Lactobacillus acidipiscis and Weissella cibaria. The molecular method used failed to determine the exact taxonomic status of BH0900 and AH3133. PMID:24936378

Phenotypic and genotypic characterization of some lactic Acid bacteria isolated from bee pollen: a preliminary study.

PubMed

Belhadj, Hani; Harzallah, Daoud; Bouamra, Dalila; Khennouf, Seddik; Dahamna, Saliha; Ghadbane, Mouloud

2014-01-01

In the present work, five hundred and sixty-seven isolates of lactic acid bacteria were recovered from raw bee pollen grains. All isolates were screened for their antagonistic activity against both Gram-positive and Gram-negative pathogenic bacteria. Neutralized supernatants of 54 lactic acid bacteria (LAB) cultures from 216 active isolates inhibited the growth of indicator bacteria. They were phenotypically characterized, based on the fermentation of 39 carbohydrates. Using the simple matching coefficient and unweighted pair group algorithm with arithmetic averages (UPGMA), seven clusters with other two members were defined at the 79% similarity level. The following species were characterized: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Pediococcus acidilactici, Pediococcus pentosaceus, and unidentified lactobacilli. Phenotypic characteristics of major and minor clusters were also identified. Partial sequencing of the 16S rRNA gene of representative isolates from each cluster was performed, and ten strains were assigned to seven species: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Lactobacillus ingluviei, Pediococcus pentosaceus, Lactobacillus acidipiscis and Weissella cibaria. The molecular method used failed to determine the exact taxonomic status of BH0900 and AH3133.

Isolation and characterization of plant growth promoting endophytic diazotrophic bacteria from Korean rice cultivars.

PubMed

Ji, Sang Hye; Gururani, Mayank Anand; Chun, Se-Chul

2014-01-20

We have isolated 576 endophytic bacteria from the leaves, stems, and roots of 10 rice cultivars and identified 12 of them as diazotrophic bacteria using a specific primer set of nif gene. Through 16S rDNA sequence analysis, nifH genes were confirmed in the two species of Penibacillus, three species of Microbacterium, three Bacillus species, and four species of Klebsiella. Rice seeds treated with these plant growth-promoting bacteria (PGPB) showed improved plant growth, increased height and dry weight and antagonistic effects against fungal pathogens. In addition, auxin and siderophore producing ability, and phosphate solubilizing activity were studied for the possible mechanisms of plant growth promotion. Among 12 isolates tested, 10 strains have shown higher auxin producing activity, 6 isolates were confirmed as strains with high siderophore producing activity while 4 isolates turned out to have high phosphate-solubilizing activity. These results strongly suggest that the endophytic diazotrophic bacteria characterized in this study could be successfully used to promote plant growth and inducing fungal resistance in plants. Copyright © 2013 Elsevier GmbH. All rights reserved.

Identification of Native Bacteria of the Candelaria and Tatacoa Semiarid Zone, Capable of Withstanding a Mars UV Radiation Simulation

NASA Astrophysics Data System (ADS)

Mendez, Y.; Vives, M.

2017-07-01

This work is the first study to describe native bacteria from the semi-arid areas in Candelaria and Tatacoa in Colombia, able to withstand a simulation of UV radiation, in order to draw an analogy with microbial growth on the surface of Mars. Sampling was carried out in the areas mentioned taking 50 samples of sediment divided into 25 samples of surface and 25 deep samples. As soon as the samples were transferred, they were subjected to a test of UV radiation in an atmospheric simulation chamber designed for the experiment, for periods of 1, 6 and 12 hours of exposure. Microbiological analysis as a method of plate dilution and isolation were performed using the modified AIS growth medium, macroscopic and microscopic description of morphotypes, biochemical identification of the morphotypes found, extraction of the feasible mycelium, DNA extraction and amplification of the gene 16 S by PCR. 13 morphotypes of bacteria resistant to UV radiation were found, mostly compatible with the gender of Streptomyces. One of the morphotypes found resisted 12 hours exposure. Molecular analyzes did not produce any results, because it was not possible to amplify the 16S by PCR, this may be due to that the exposure to UV radiation can degrade the DNA in existence, a affecting the results. The finding of native bacteria capable of withstanding conditions UV radiation can give us an approximation of microbial growth, mechanisms of resistance and survival under extreme conditions such as those found on Mars, in order to develop biotechnological applications and establish planetary analogues to understand the origin and evolution of the universe.

Cloud-enabled microscopy and droplet microfluidic platform for specific detection of Escherichia coli in water.

PubMed

Golberg, Alexander; Linshiz, Gregory; Kravets, Ilia; Stawski, Nina; Hillson, Nathan J; Yarmush, Martin L; Marks, Robert S; Konry, Tania

2014-01-01

We report an all-in-one platform - ScanDrop - for the rapid and specific capture, detection, and identification of bacteria in drinking water. The ScanDrop platform integrates droplet microfluidics, a portable imaging system, and cloud-based control software and data storage. The cloud-based control software and data storage enables robotic image acquisition, remote image processing, and rapid data sharing. These features form a "cloud" network for water quality monitoring. We have demonstrated the capability of ScanDrop to perform water quality monitoring via the detection of an indicator coliform bacterium, Escherichia coli, in drinking water contaminated with feces. Magnetic beads conjugated with antibodies to E. coli antigen were used to selectively capture and isolate specific bacteria from water samples. The bead-captured bacteria were co-encapsulated in pico-liter droplets with fluorescently-labeled anti-E. coli antibodies, and imaged with an automated custom designed fluorescence microscope. The entire water quality diagnostic process required 8 hours from sample collection to online-accessible results compared with 2-4 days for other currently available standard detection methods.

Cloud-Enabled Microscopy and Droplet Microfluidic Platform for Specific Detection of Escherichia coli in Water

PubMed Central

Kravets, Ilia; Stawski, Nina; Hillson, Nathan J.; Yarmush, Martin L.; Marks, Robert S.; Konry, Tania

2014-01-01

We report an all-in-one platform – ScanDrop – for the rapid and specific capture, detection, and identification of bacteria in drinking water. The ScanDrop platform integrates droplet microfluidics, a portable imaging system, and cloud-based control software and data storage. The cloud-based control software and data storage enables robotic image acquisition, remote image processing, and rapid data sharing. These features form a “cloud” network for water quality monitoring. We have demonstrated the capability of ScanDrop to perform water quality monitoring via the detection of an indicator coliform bacterium, Escherichia coli, in drinking water contaminated with feces. Magnetic beads conjugated with antibodies to E. coli antigen were used to selectively capture and isolate specific bacteria from water samples. The bead-captured bacteria were co-encapsulated in pico-liter droplets with fluorescently-labeled anti-E. coli antibodies, and imaged with an automated custom designed fluorescence microscope. The entire water quality diagnostic process required 8 hours from sample collection to online-accessible results compared with 2–4 days for other currently available standard detection methods. PMID:24475107

Nitrite oxidizing bacteria for water treatment in coastal aquaculture system

NASA Astrophysics Data System (ADS)

Noorak, S.; Rakkhiaw, S.; Limjirakhajornt, K.; Uppabullung, A.; Keawtawee, T.; Sangnoi, Y.

2018-04-01

This research aimed to isolate and characterize nitrite oxidizing bacteria and to study their capability for water quality improvement. Fourteen strains of bacteria with nitrite-oxidizing character were isolated after 21 days of enrichment in Pep-Beef-NOB medium contained NaNO2. Two strains, SF-1 and SF-5, showed highest nitrite removal rate for 42.42% and 37.2%, respectively. These strains were determined an efficiency of open-system wastewater treatment for 14 days. The results showed that control, SF-1 and SF-5 had remove ammonia from day 1 to day 6. At the end of the study, ammonia was removed by the control, SF-1 and SF-5 for 81.27%, 70.1% and 69.82%, respectively. Nitrite concentration was lowest at day 8 with removal rate of 98.73%, 98.3% and 97.24% from control, SF-1 and SF-5, respectively. However, nitrite concentration in control experiment was increased again at day 11 whereas in SF-1 and SF-5 were increased at day 13. Chemical Oxygen Demand (COD) was decreased by 77.78%, 73.50% and 78.63% in the control, SF-1 and SF-5, respectively. Biological Oxygen Demand (BOD) in the control, SF-1 and SF-5 were reduced by 85.92%, 79.53% and 82.09%, respectively. Based on 16S rRNA gene, SF-1 and SF-5 were identified as Bacillus vietnamensis and B. firmus, respectively.

Secondary metabolites produced by the marine bacterium Halobacillus salinus that inhibit quorum sensing-controlled phenotypes in gram-negative bacteria.

PubMed

Teasdale, Margaret E; Liu, Jiayuan; Wallace, Joselynn; Akhlaghi, Fatemeh; Rowley, David C

2009-02-01

Certain bacteria use cell-to-cell chemical communication to coordinate community-wide phenotypic expression, including swarming motility, antibiotic biosynthesis, and biofilm production. Here we present a marine gram-positive bacterium that secretes secondary metabolites capable of quenching quorum sensing-controlled behaviors in several gram-negative reporter strains. Isolate C42, a Halobacillus salinus strain obtained from a sea grass sample, inhibits bioluminescence production by Vibrio harveyi in cocultivation experiments. With the use of bioassay-guided fractionation, two phenethylamide metabolites were identified as the active agents. The compounds additionally inhibit quorum sensing-regulated violacein biosynthesis by Chromobacterium violaceum CV026 and green fluorescent protein production by Escherichia coli JB525. Bacterial growth was unaffected at concentrations below 200 microg/ml. Evidence is presented that these nontoxic metabolites may act as antagonists of bacterial quorum sensing by competing with N-acyl homoserine lactones for receptor binding.

Screening and identification of a cutinase-producing Rhodotorula mucilaginosa and properties of the cutinase.

PubMed

Zhang, Xiao-Ning; Ran, Qin-Qin; Zhang, Xuejun

2015-01-01

Eucommia leaf contains large amounts of natural active products. In extracting the substances, the most important is the removal of the cuticle layer on the leaves and the cell wall in the leaves of Eucommia ulmoides. But the removal of the cuticle layer is a technical difficulty now. Cutinase (EC3.1.1.74) is a multifunctional enzyme with a common alpha/beta fold structure belonging to hydroplane that can make a substantial degradation of horny fatty acids. So this study isolated bacteria capable of producing cutinase from the lesion of Eucommia leaves and identified the bacteria. The identification using PCR-RFLP method confirmed that the strain belongs to Rhodotorula mucilaginosa. The fermentation conditions of the strain-producing cutinase were optimized in this study. The finding of cutinase-producing R. mucilaginosa is significant because the yeast is more secure than plant pathogens, being suitable for mass production.

Lipopolysaccharide induces amyloid formation of antimicrobial peptide HAL-2.

PubMed

Wang, Jiarong; Li, Yan; Wang, Xiaoming; Chen, Wei; Sun, Hongbin; Wang, Junfeng

2014-11-01

Lipopolysaccharide (LPS), the important component of the outer membrane of Gram-negative bacteria, contributes to the integrity of the outer membrane and protects the cell against bactericidal agents, including antimicrobial peptides. However, the mechanisms of interaction between antimicrobial peptides and LPS are not clearly understood. Halictines-2 (HAL-2), one of the novel antimicrobial peptides, was isolated from the venom of the eusocial bee Halictus sexcinctus. HAL-2 has exhibited potent antimicrobial activity against Gram-positive and Gram-negative bacteria and even against cancer cells. Here, we studied the interactions between HAL-2 and LPS to elucidate the antibacterial mechanism of HAL-2 in vitro. Our results show that HAL-2 adopts a significant degree of β-strand structure in the presence of LPS. LPS is capable of inducing HAL-2 amyloid formation, which may play a vital role in its antimicrobial activity. Copyright © 2014 Elsevier B.V. All rights reserved.

The bioleaching potential of a bacterial consortium.

PubMed

Latorre, Mauricio; Cortés, María Paz; Travisany, Dante; Di Genova, Alex; Budinich, Marko; Reyes-Jara, Angélica; Hödar, Christian; González, Mauricio; Parada, Pilar; Bobadilla-Fazzini, Roberto A; Cambiazo, Verónica; Maass, Alejandro

2016-10-01

This work presents the molecular foundation of a consortium of five efficient bacteria strains isolated from copper mines currently used in state of the art industrial-scale biotechnology. The strains Acidithiobacillus thiooxidans Licanantay, Acidiphilium multivorum Yenapatur, Leptospirillum ferriphilum Pañiwe, Acidithiobacillus ferrooxidans Wenelen and Sulfobacillus thermosulfidooxidans Cutipay were selected for genome sequencing based on metal tolerance, oxidation activity and bioleaching of copper efficiency. An integrated model of metabolic pathways representing the bioleaching capability of this consortium was generated. Results revealed that greater efficiency in copper recovery may be explained by the higher functional potential of L. ferriphilum Pañiwe and At. thiooxidans Licanantay to oxidize iron and reduced inorganic sulfur compounds. The consortium had a greater capacity to resist copper, arsenic and chloride ion compared to previously described biomining strains. Specialization and particular components in these bacteria provided the consortium a greater ability to bioleach copper sulfide ores. Copyright © 2016 Elsevier Ltd. All rights reserved.

Diversity and antifungal activity of endophytic diazotrophic bacteria colonizing sugarcane in Egypt

USDA-ARS?s Scientific Manuscript database

The price of nitrogen continues to increase and is a major input in sugarcane production. Sugarcane grown in Egypt was screened for the presence of nitrogen-fixing bacteria. Nitrogen-free medium LGI-P was used to isolate bacteria from cane stalks. Among the 52 isolates subjected to acetylene redu...

Antibiotic resistance patterns in fecal bacteria isolated from Christmas shearwater (Puffinus nativitatis) and masked booby (Sula dactylatra) at remote Easter Island.

PubMed

Ardiles-Villegas, Karen; González-Acuña, Daniel; Waldenström, Jonas; Olsen, Björn; Hernández, Jorge

2011-09-01

Antibiotic use and its implications have been discussed extensively in the past decades. This situation has global consequences when antibiotic resistance becomes widespread in the intestinal bacterial flora of stationary and migratory birds. This study investigated the incidence of fecal bacteria and general antibiotic resistance, with special focus on extended spectrum beta-lactamase (ESBL) isolates, in two species of seabirds at remote Easter Island. We identified 11 species of bacteria from masked booby (Sula dactylatra) and Christmas shearwater (Puffinus nativitatis); five species of gram-negative bacilli, four species of Streptococcus (Enterococcus), and 2 species of Staphylococcus. In addition, 6 types of bacteria were determined barely to the genus level. General antibiotic susceptibility was measured in the 30 isolated Enterobacteriaceae to 11 antibiotics used in human and veterinary medicine. The 10 isolates that showed a phenotypic ESBL profile were verified by clavulanic acid inhibition in double mixture discs with cefpodoxime, and two ESBL strains were found, one strain in masked booby and one strain in Christmas shearwater. The two bacteria harboring the ESBL type were identified as Serratia odorifera biotype 1, which has zoonotic importance. Despite minimal human presence in the masked booby and Christmas shearwater habitats, and the extreme geographic isolation of Easter Island, we found several multiresistant bacteria and even two isolates with ESBL phenotypes. The finding of ESBLs has animal and public health significance and is of potential concern, especially because the investigation was limited in size and indicated that antibiotic-resistant bacteria now are distributed globally.

Aerobic salivary bacteria in wild and captive Komodo dragons.

PubMed

Montgomery, Joel M; Gillespie, Don; Sastrawan, Putra; Fredeking, Terry M; Stewart, George L

2002-07-01

During the months of November 1996, August 1997, and March 1998, saliva and plasma samples were collected for isolation of aerobic bacteria from 26 wild and 13 captive Komodo dragons (Varanus komodoensis). Twenty-eight Gram-negative and 29 Gram-positive species of bacteria were isolated from the saliva of the 39 Komodo dragons. A greater number of wild than captive dragons were positive for both Gram-negative and Gram-positive bacteria. The average number of bacterial species within the saliva of wild dragons was 46% greater than for captive dragons. While Escherichia coli was the most common bacterium isolated from the saliva of wild dragons, this species was not present in captive dragons. The most common bacteria isolated from the saliva of captive dragons were Staphylococcus capitis and Staphylococcus capitis and Staphylococcus caseolyticus, neither of which were found in wild dragons. High mortality was seen among mice injected with saliva from wild dragons and the only bacterium isolated from the blood of dying mice was Pasteurella multocida. A competitive inhibition enzyme-linked immunosorbent assay revealed the presence of anti-Pasteurella antibody in the plasma of Komodo dragons. Four species of bacteria isolated from dragon saliva showed resistance to one or more of 16 antimicrobics tested. The wide variety of bacteria demonstrated in the saliva of the Komodo dragon in this study, at least one species of which was highly lethal in mice and 54 species of which are known pathogens, support the observation that wounds inflicted by this animal are often associated with sepsis and subsequent bacteremia in prey animals.

Identification and Pathogenicity of Bacteria Associated with Etiolation and Decline of Creeping Bentgrass Golf Course Putting Greens.

PubMed

Roberts, Joseph A; Ma, Bangya; Tredway, Lane P; Ritchie, David F; Kerns, James P

2018-01-01

Bacterial etiolation and decline has developed into a widespread issue with creeping bentgrass (CBG) (Agrostis stolonifera) putting green turf. The condition is characterized by an abnormal elongation of turfgrass stems and leaves that in rare cases progresses into a rapid and widespread necrosis and decline. Recent reports have cited bacteria, Acidovorax avenae and Xanthomonas translucens, as causal agents; however, few cases exist where either bacterium were isolated in conjunction with turf exhibiting bacterial disease symptoms. From 2010 to 2014, turfgrass from 62 locations submitted to the NC State Turf Diagnostic Clinic exhibiting bacterial etiolation and/or decline symptoms were sampled for the presence of bacterial pathogens. Isolated bacteria were identified using rRNA sequencing of the 16S subunit and internal transcribed spacer region (16S-23S or ITS). Results showed diverse bacteria isolated from symptomatic turf and A. avenae and X. translucens were only isolated in 26% of samples. Frequently isolated bacterial species were examined for pathogenicity to 4-week-old 'G2' CBG seedlings and 8-week-old 'A-1' CBG turfgrass stands in the greenhouse. While results confirmed pathogenicity of A. avenae and X. translucens, Pantoea ananatis was also shown to infect CBG turf; although pathogenicity varied among isolated strains. These results illustrate that multiple bacteria are associated with bacterial disease and shed new light on culturable bacteria living in CBG turfgrass putting greens. Future research to evaluate additional microorganisms (i.e., bacteria and fungi) could provide new information on host-microbe interactions and possibly develop ideas for management tactics to reduce turfgrass pests.

Actinomycetes in Karstic caves of northern Spain (Altamira and Tito Bustillo).

PubMed

Groth, I; Vettermann, R; Schuetze, B; Schumann, P; Saiz-Jimenez, C

1999-05-01

A variety of isolation procedures were carried out to study the involvement of bacteria in the colonisation and biodeterioration of Spanish caves with paleolithic rock art (Altamira and Tito Bustillo). The applied techniques mainly aimed to isolate heterotrophic bacteria such as streptomycetes, nocardioform and coryneform actinomycetes, and other gram-positive and gram-negative bacteria. The results demonstrated that actinomycetes were the most abundant gram-positive bacteria in the caves. Actinomycetes revealed a great taxonomic diversity with the predominant isolates belonging to the genus Streptomyces. Members of the genera Nocardia, Rhodococcus, Nocardioides, Amycolatopsis, Saccharothrix, Brevibacterium, Microbacterium, and coccoid actinomycetes (family Micrococcaceae) were also found.

A Comparative Study: Taxonomic Grouping of Alkaline Protease Producing Bacilli.

PubMed

Tekin, Nilgun; Cihan, Arzu Coleri; Karaca, Basar; Cokmus, Cumhur

2017-03-30

Alkaline proteases have biotechnological importance due to their activity and stability at alkaline pH. 56 bacteria, capable of growing under alkaline conditions were isolated and their alkaline protease activities were carried out at different parameters to determine their optimum alkaline protease production conditions. Seven isolates were showed higher alkaline protease production capacity than the reference strains. The highest alkaline protease producing isolates (103125 U/g), E114 and C265, were identified as Bacillus licheniformis with 99.4% and Bacillus mojavensis 99.8% based on 16S rRNA gene sequence similarities, respectively. Interestingly, the isolates identified as Bacillus safensis were also found to be high alkaline protease producing strains. Genotypic characterizations of the isolates were also determined by using a wide range of molecular techniques (ARDRA, ITS-PCR, (GTG)5-PCR, BOX-PCR). These different techniques allowed us to differentiate the alkaliphilic isolates and the results were in concurrence with phylogenetic analyses of the 16S rRNA genes. While ITS-PCR provided the highest correlation with 16S rRNA groups, (GTG)5-PCR showed the highest differentiation at species and intra-species level. In this study, each of the biotechnologically valuable alkaline protease producing isolates was grouped into their taxonomic positions with multi-genotypic analyses.

Revealing potential functions of VBNC bacteria in polycyclic aromatic hydrocarbons biodegradation.

PubMed

Su, X M; Bamba, A M; Zhang, S; Zhang, Y G; Hashmi, M Z; Lin, H J; Ding, L X

2018-04-01

The bioremediation of polycyclic aromatic hydrocarbon (PAH)-contaminated sites is not running smoothly, because of the lower activity of PAH-degrading bacteria in actual bioremediation applications. The phenomenon of "viable but nonculturable" (VBNC) state may be a main limiting factor for their poor biodegradation capabilities of PAHs. Due to their abilities of entering into the VBNC state, most of bacterial populations with PAH-degradation potential remain unculturable. Resuscitation of VBNC bacteria will enhance the degradation capability of indigenous bacteria which will eventually obtain their better capabilities in environmental bioremediation. Although evidences have been presented indicating that resuscitation of VBNC bacteria in polychlorinated biphenyl (PCB)-contaminated environments not only significantly enhanced PCB degradation, but also obtained novel highly efficient PCB-degrading bacteria, scanty information is available on the VBNC bacteria in PAH-contaminated sites. VBNC bacteria, as a vast majority of potential microbial resource could be the repository of novel highly efficient PAH-biodegraders. Therefore, studies need to be done on resuscitation of VBNC bacteria to overcome key bottlenecks in bioremediation of PAH-contaminated sites. This mini-review provides a new insight into the potential functions of VBNC bacteria in PAHs biodegradation. As the vast majority microbial resource, viable but nonculturable (VBNC) bacteria, which showed their potential functions in polycyclic aromatic hydrocarbons (PAHs) biodegradation, can be of great significance in environmental bioremediation. It is therefore important to resuscitate VBNC bacteria for their better capabilities. Meanwhile, preventing the indigenous functional community from entering into the VBNC state will also maintain the high activity of PAH-degrading bacteria in actual bioremediation applications. Undoubtedly, much more work needs to be done to reveal indigenous micro-organisms in the VBNC state from the perspective of environmental functions. © 2018 The Society for Applied Microbiology.

Microbiota from Litopenaeus vannamei: digestive tract microbial community of Pacific white shrimp (Litopenaeus vannamei).

PubMed

Tzuc, Jaqueline Tuyub; Escalante, Diana Rendíz; Rojas Herrera, Rafael; Gaxiola Cortés, Gabriela; Ortiz, Maria Leticia Arena

2014-01-01

Bacteria capable of producing different extracellular enzymes of potential relevance in digestive processes were isolated from the stomach, hepatopancreas and intestine of Pacific white shrimp Litopenaeus vannamei. A total of 64 strains with proteolytic activity were isolated and grouped into 16 clusters based on morphological characteristics: 4 groups were isolated from the intestine; 5 from the hepatopancreas; and 7 from the stomach. Molecular methods (16S rRNA gene amplification and sequencing) and phenotypic criteria (Gram stain, catalase and oxidase tests, cell and colony morphology) were used to identify strains, which corresponded to Pseudoalteromonas and Vibrio genera. These genera are reported to form part of the digestive tract microbial community in shrimp. Both genera were isolated from all three tested tissues. One member of each morphologic group was selected for analysis of the presence of amylases, lipases/esterases and chitinases. Most of the strains had all the tested enzymes, indicating that the L. vannamei digestive tract microbiotic flora includes groups which have the potential to contribute to the degradation of dietary components.

Plant growth promoting capability and genetic diversity of bacteria isolated from mud volcano and lime cave of Andaman and Nicobar Islands

PubMed Central

Venkadesaperumal, Gopu; Amaresan, Natrajan; Kumar, Krishna

2014-01-01

Twenty four bacterial strains from four different regions of mud volcano and lime cave were isolated to estimate their diversity, plant growth promoting and biocontrol activities to use them as inoculant strains in the fields. An excellent antagonistic effect against four plant pathogens and plant growth promoting properties such as IAA production, HCN production, phosphate solubilization, siderophore production, starch hydrolysis and hydrolytic enzymes syntheses were identified in OM5 (Pantoea agglomerans) and EM9 (Exiguobacterium sp.) of 24 studied isolates. Seeds (Chili and tomato) inoculation with plant growth promoting strains resulted in increased percentage of seedling emergence, root length and plant weight. Results indicated that co-inoculation gave a more pronounced effects on seedling emergence, secondary root numbers, primary root length and stem length, while inoculation by alone isolate showed a lower effect. Our results suggest that the mixed inocula of OM5 and EM9 strains as biofertilizers could significantly increase the production of food crops in Andaman archipelago by means of sustainable and organic agricultural system. PMID:25763031

Plant growth promoting capability and genetic diversity of bacteria isolated from mud volcano and lime cave of Andaman and Nicobar Islands.

PubMed

Venkadesaperumal, Gopu; Amaresan, Natrajan; Kumar, Krishna

2014-01-01

Twenty four bacterial strains from four different regions of mud volcano and lime cave were isolated to estimate their diversity, plant growth promoting and biocontrol activities to use them as inoculant strains in the fields. An excellent antagonistic effect against four plant pathogens and plant growth promoting properties such as IAA production, HCN production, phosphate solubilization, siderophore production, starch hydrolysis and hydrolytic enzymes syntheses were identified in OM5 (Pantoea agglomerans) and EM9 (Exiguobacterium sp.) of 24 studied isolates. Seeds (Chili and tomato) inoculation with plant growth promoting strains resulted in increased percentage of seedling emergence, root length and plant weight. Results indicated that co-inoculation gave a more pronounced effects on seedling emergence, secondary root numbers, primary root length and stem length, while inoculation by alone isolate showed a lower effect. Our results suggest that the mixed inocula of OM5 and EM9 strains as biofertilizers could significantly increase the production of food crops in Andaman archipelago by means of sustainable and organic agricultural system.

Microbial Surveillance of Potable Water Sources of the International Space Station

NASA Technical Reports Server (NTRS)

Bruce, Rebekah J.; Ott, C. Mark; Skuratov, Vladimir M.; Pierson, Duane L.

2005-01-01

To mitigate risk to the crew, the microbial surveillance of the quality of potable water sources of the International Space Station (ISS) has been ongoing since before the arrival of the first permanent crew. These water sources have included stored ground-supplied water, water produced by the shuttle fuel cells during flight, and ISS humidity condensate that is reclaimed and processed. Monitoring was accomplished using a self-contained filter designed to allow bacterial growth and enumeration during flight. Upon return to earth, microbial isolates were identified using 16S ribosomal gene sequencing. While the predominant isolates were common Gramnegative bacteria including Ralstonia eutropha, Methylobacterium fujisawaense, and Spingomonas paucimobilis, opportunistic pathogens such as Stenotrophomonas maltophilia and Pseudomonas aeruginosa were also isolated. Results of in-flight enumeration have indicated a fluctuation of bacterial counts above system design specifications. Additional in-flight monitoring capability for the specific detection of coliforms was added in 2004; no coliforms have been detected from any potable water source. Neither the bacterial concentrations nor the identification of the isolates recovered from these samples has suggested a threat to crew health.

Identification of beer-spoilage bacteria using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

PubMed

Wieme, Anneleen D; Spitaels, Freek; Aerts, Maarten; De Bruyne, Katrien; Van Landschoot, Anita; Vandamme, Peter

2014-08-18

Applicability of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for identification of beer-spoilage bacteria was examined. To achieve this, an extensive identification database was constructed comprising more than 4200 mass spectra, including biological and technical replicates derived from 273 acetic acid bacteria (AAB) and lactic acid bacteria (LAB), covering a total of 52 species, grown on at least three growth media. Sequence analysis of protein coding genes was used to verify aberrant MALDI-TOF MS identification results and confirmed the earlier misidentification of 34 AAB and LAB strains. In total, 348 isolates were collected from culture media inoculated with 14 spoiled beer and brewery samples. Peak-based numerical analysis of MALDI-TOF MS spectra allowed a straightforward species identification of 327 (94.0%) isolates. The remaining isolates clustered separately and were assigned through sequence analysis of protein coding genes either to species not known as beer-spoilage bacteria, and thus not present in the database, or to novel AAB species. An alternative, classifier-based approach for the identification of spoilage bacteria was evaluated by combining the identification results obtained through peak-based cluster analysis and sequence analysis of protein coding genes as a standard. In total, 263 out of 348 isolates (75.6%) were correctly identified at species level and 24 isolates (6.9%) were misidentified. In addition, the identification results of 50 isolates (14.4%) were considered unreliable, and 11 isolates (3.2%) could not be identified. The present study demonstrated that MALDI-TOF MS is well-suited for the rapid, high-throughput and accurate identification of bacteria isolated from spoiled beer and brewery samples, which makes the technique appropriate for routine microbial quality control in the brewing industry. Copyright © 2014 Elsevier B.V. All rights reserved.

Rapid isolation of gluten-digesting bacteria from human stool and saliva by using gliadin-containing plates

PubMed Central

Sarantopoulos, Christos; Ongchangco, Deryn; Sry, Jeremy; Cesario, Thomas

2014-01-01

The number of individuals with gluten intolerance has increased dramatically over the last years. To date, the only therapy for gluten intolerance is the complete avoidance of dietary gluten. To sustain a strictly gluten-free diet, however, is very challenging. Therefore, there is need for a non-dietary therapy. Any such treatment must appreciate that the immunogenic part of gluten are gliadin peptides which are poorly degraded by the enzymes of the gastrointestinal tract. Probiotic therapy and oral enzyme therapy containing gluten-degrading bacteria (GDB) and their gliadin-digesting enzymes are possible new approaches for the treatment of gluten intolerance, however effectively isolating GDB for these treatments is problematic. The goal of this study was to develop an easy technique to isolate GDB rapidly and efficiently with the hope it might lead to newer ways of developing either probiotics or traditional medicines to treat gluten intolerance. Several researchers have already isolated successfully GDB by using gluten minimal or limited agar plates. Although these plates can be used to isolate bacteria which can tolerate gluten, further assays are needed to investigate if the same bacteria can also digest gluten. The agar plates we developed can detect bacteria which cannot only tolerate gluten but are able to digest it as well. Therefore, we were able to combine two steps into one step. Using such technologies, we were able to isolate five GDB from saliva and stool, and identified three bacterial reference strains with gluten-degrading activity. The technique we developed to isolate bacteria with gluten-degrading activity is fast, effective, and easy to use. The GDB isolated by our technology could have potential as part of a probiotic or enzymatic therapy for people with gluten intolerance. PMID:25519429

BACTERIAL PROFILE OF NECROTIC PULPS IN CHEETAH (ACINONYX JUBATUS) CANINE TEETH.

PubMed

Almansa Ruiz, José C; Bosman, Anna-Mari; Steenkamp, Gerhard

2016-03-01

The role of microbes and their antimicrobial susceptibilities in both acute and chronic infections of the dental pulp in humans has been well studied. Presently, no data are available on endodontic pathogens in cheetahs (Acinonyx jubatus). The aim of this study was to isolate and identify the bacteria found in the canine teeth of cheetahs, where the pulp was necrotic and exposed due to a complicated crown fracture. Thirty-six microbiologic samples were taken from root canals (RCs) of the canine teeth of 19 cheetahs: one pulp sample was taken from 10 cheetahs, four samples from 2 cheetahs, two samples from 3 cheetahs, and three samples from 4 cheetahs. Exposed pulps were cultured for aerobic and anaerobic bacteria; an additional screening with a 16S rRNA-specific polymerase chain reaction (PCR) was used for the last six samples. Antimicrobial susceptibility of isolates was determined by use of the Kirby-Bauer diffusion test. In total, 59 cultivable isolates belonging to 19 microbial species and 13 genera were recovered from the 36 RCs sampled. Only two samples yielded no cultivable bacteria. Thirty-two (54.49%) of the cultivable isolates were Gram positive and 27 (45.71%) were Gram negative. The maximum number of isolates cultivated from an individual RC was six. Facultative anaerobes (62.72%) were the most common bacteria of the RCs that yielded cultivable bacteria. Of the isolates, 28.81% were aerobic and 8.47% were strict anaerobes. The antimicrobials that showed the greatest efficacy in vitro against the different bacteria isolates were amikacin and gentamicin. The more common bacterial species isolated by PCR were anaerobes (60.8%), facultative anaerobes (30.2%), and aerobes (8.6%).

Sugarcane bagasse as support for immobilization of Bacillus pumilus HZ-2 and its use in bioremediation of mesotrione-contaminated soils.

PubMed

Liu, Jie; Chen, Shaohua; Ding, Jie; Xiao, Ying; Han, Haitao; Zhong, Guohua

2015-12-01

The degrading microorganisms isolated from environment usually fail to degrade pollutants when used for bioremediation of contaminated soils; thus, additional treatments are needed to enhance biodegradation. In the present study, the potential of sugarcane bagasse as bacteria-immobilizing support was investigated in mesotrione biodegradation. A novel isolate Bacillus pumilus HZ-2 was applied in bacterial immobilization, which was capable of degrading over 95 % of mesotrione at initial concentrations ranging from 25 to 200 mg L(-1) within 4 days in flask-shaking tests. Scanning electron microscope (SEM) images showed that the bacterial cells were strongly absorbed and fully dispersed on bagasse surface after immobilization. Specially, 86.5 and 82.9 % of mesotrione was eliminated by bacteria immobilized on bagasse of 100 and 60 mesh, respectively, which indicated that this immobilization was able to maintain a high degrading activity of the bacteria. Analysis of the degradation products determined 2-amino-4-methylsulfonylbenzoic acid (AMBA) and 4-methylsulfonyl-2-nitrobenzoic acid (MNBA) as the main metabolites in the biodegradation pathway of mesotrione. In the sterile soil, approximately 90 % of mesotrione was degraded after supplementing 5.0 % of molasses in bacteria-bagasse composite, which greatly enhanced microbial adaptability and growth in the soil environment. In the field tests, over 75 % of mesotrione in soil was degraded within 14 days. The immobilized preparation demonstrated that mesotrione could be degraded at a wide range of pH values (5.0-8.0) and temperatures (25-35 °C), especially at low concentrations of mesotrione (5 to 20 mg kg(-1)). These results showed that sugarcane bagasse might be a good candidate as bacteria-immobilizing support to enhance mesotrione degradation by Bacillus p. HZ-2 in contaminated soils.

Antimicrobial and Efflux Pump Inhibitory Activity of Caffeoylquinic Acids from Artemisia absinthium against Gram-Positive Pathogenic Bacteria

PubMed Central

Fiamegos, Yiannis C.; Kastritis, Panagiotis L.; Exarchou, Vassiliki; Han, Haley; Bonvin, Alexandre M. J. J.; Vervoort, Jacques; Lewis, Kim; Hamblin, Michael R.; Tegos, George P.

2011-01-01

Background Traditional antibiotics are increasingly suffering from the emergence of multidrug resistance amongst pathogenic bacteria leading to a range of novel approaches to control microbial infections being investigated as potential alternative treatments. One plausible antimicrobial alternative could be the combination of conventional antimicrobial agents/antibiotics with small molecules which block multidrug efflux systems known as efflux pump inhibitors. Bioassay-driven purification and structural determination of compounds from plant sources have yielded a number of pump inhibitors which acted against gram positive bacteria. Methodology/Principal Findings In this study we report the identification and characterization of 4′,5′-O-dicaffeoylquinic acid (4′,5′-ODCQA) from Artemisia absinthium as a pump inhibitor with a potential of targeting efflux systems in a wide panel of Gram-positive human pathogenic bacteria. Separation and identification of phenolic compounds (chlorogenic acid, 3′,5′-ODCQA, 4′,5′-ODCQA) was based on hyphenated chromatographic techniques such as liquid chromatography with post column solid-phase extraction coupled with nuclear magnetic resonance spectroscopy and mass spectroscopy. Microbial susceptibility testing and potentiation of well know pump substrates revealed at least two active compounds; chlorogenic acid with weak antimicrobial activity and 4′,5′-ODCQA with pump inhibitory activity whereas 3′,5′-ODCQA was ineffective. These intitial findings were further validated with checkerboard, berberine accumulation efflux assays using efflux-related phenotypes and clinical isolates as well as molecular modeling methodology. Conclusions/Significance These techniques facilitated the direct analysis of the active components from plant extracts, as well as dramatically reduced the time needed to analyze the compounds, without the need for prior isolation. The calculated energetics of the docking poses supported the biological information for the inhibitory capabilities of 4′,5′-ODCQA and furthermore contributed evidence that CQAs show a preferential binding to Major Facilitator Super family efflux systems, a key multidrug resistance determinant in gram-positive bacteria. PMID:21483731

Microbial Populations Growing in the Presence of Fluoride at Low pH Isolated from Dental Plaque of Children Living in an Area with Fluoridated Water

PubMed Central

Bowden, G. H. W.; Odlum, O.; Nolette, N.; Hamilton, I. R.

1982-01-01

Longitudinal microbiological examinations have been made of dental plaque from a site approximal to the upper central incisors of 10 8-year-old children living in an area with water fluoridation. Differential counts of viable bacteria, made using a selective medium containing various levels of fluoride (0 to 100 μg/ml) at pH levels of 7.0 to 5.5, demonstrated an effect of both pH and fluoride on the numbers and types of bacteria isolated. Strains of Streptococcus and Neisseria grew after only 16 h of incubation at pH levels as low as 6.0 with fluoride levels up to 50 μg/ml. The most commonly isolated streptococci were Streptococcus mitior and S. salivarius. S. mutans was isolated less frequently and was inhibited by 20 and 50 μg of fluoride per ml at pH 6.0 and 6.5, respectively. Veillonella strains were the most resistant isolates, being isolated after 16 h of incubation on media at pH 6.0 with 100 μg of fluoride per ml. Despite their known fluoride resistance, Actinomyces spp. were often only detected on the selective media after 72 h of incubation. The pH of the medium had a definite selective effect, as the number of colonies growing on the fluoride-free basal media at pH 6.0 was only 30% of that at pH 7.0. Representative strains of S. mutans, S. mitior, S. sanguis, and S. milleri were tested for their ability to utilize glucose at the pH and fluoride levels of the medium on which they were initially isolated. Fluoride reduced the initial glycolytic rate of the cells, but in 5 of the 13 strains tested the final amount of glucose used after 2 h of incubation was the same in the presence or absence of fluoride. The isolation of bacteria capable of growth in the presence of fluoride over a significant portion of the pH range that occurs in plaque in vivo could explain in part the finding that fluoride does not have a dramatic effect on the plaque community. Fluoride in plaque may reduce the ecological advantage afforded to aciduric S. mutans strains by carbohydrate substances. In the in vivo situation this could mean that, even with high carbohydrate intake, fluoride may permit S. mitior to compete with S. mutans within the plaque ecosystem. PMID:7076297

Diversity and antimicrobial potential in sea anemone and holothurian microbiomes.

PubMed

León-Palmero, Elizabeth; Joglar, Vanessa; Álvarez, Pedro A; Martín-Platero, Antonio; Llamas, Inmaculada; Reche, Isabel

2018-01-01

Marine invertebrates, as holobionts, contain symbiotic bacteria that coevolve and develop antimicrobial substances. These symbiotic bacteria are an underexplored source of new bioactive molecules to face the emerging antibiotic resistance in pathogens. Here, we explored the antimicrobial activity of bacteria retrieved from the microbiota of two sea anemones (Anemonia sulcata, Actinia equina) and two holothurians (Holothuria tubulosa, Holothuria forskali). We tested the antimicrobial activity of the isolated bacteria against pathogens with interest for human health, agriculture and aquaculture. We isolated 27 strains with antibacterial activity and 12 of these isolates also showed antifungal activity. We taxonomically identified these strains being Bacillus and Vibrio species the most representative producers of antimicrobial substances. Microbiome species composition of the two sea anemones was similar between them but differed substantially of seawater bacteria. In contrast, microbiome species composition of the two holothurian species was different between them and in comparison with the bacteria in holothurian feces and seawater. In all the holobiont microbiomes Bacteroidetes was the predominant phylum. For each microbiome, we determined diversity and the rank-abundance dominance using five fitted models (null, pre-emption, log-Normal, Zipf and Zipf-Mandelbrot). The models with less evenness (i.e. Zipf and Zipf-Mandelblot) showed the best fits in all the microbiomes. Finally, we tracked (using the V4 hypervariable region of 16S rRNA gene) the relative abundance of these 27 isolates with antibacterial activity in the total pool of sequences obtained for the microbiome of each holobiont. Coincidences, although with extremely low frequencies, were detected only in the microbiome of H. forskali. This fact suggests that these isolated bacteria belong to the long tail of rare symbiotic bacteria. Therefore, more and more sophisticated culture techniques are necessary to explore this apparently vast pool of rare symbiontic bacteria and to determine their biotechnological potentiality.

Anaerobic infections in surgical wards: a two year study

PubMed Central

Ananth-Shenoy, Padmaja; Vishwanath, Shashidhar; Targain, Ryumzook; Shetty, Seema; Sunil-Rodrigues, Gabriel; Mukhopadhyay, Chiranjay; Chawla, Kiran

2016-01-01

Background and Objectives: Anaerobic bacteria are recognized as important pathogens in surgical infections. However, they are the most overlooked microorganisms by the clinic and the laboratory because of the tedious culture techniques with longer turn-around times. The study was aimed to analyze the frequency of anaerobic bacterial surgical infections and their predisposing factors. Materials and Methods: A retrospective study was conducted over a period of two years including patients with surgical infections. The specimens were processed by Gram staining, aerobic and anaerobic culture. The anaerobic bacteria were isolated using standard procedures. The predisposing factors and clinical presentation were studied in these patients. Results: A total of 261 specimens were received from patients with diverse infections from surgical wards. Ninety-one anaerobes were isolated from 64 (24.5%) surgical patients with a predominance of Gram-negative bacilli (37.4%). Anaerobic bacteria as monomicrobial isolates were seen in 21.9% isolates. Anaerobic bacterial isolation along with aerobic bacteria was seen in 71.9% of patients and polymicrobial anaerobic growth was detected in 6.3% of patients. Diabetes mellitus (28, 43.8%) was found to be the most frequent predisposing factor. Bacteroides fragilis group (20.9%) were the most frequent anaerobic Gram-negative bacilli followed by Prevotella spp. (12.1%). Peptostreptococcus anaerobius was the predominant anaerobic cocci isolated (14.3%). Necrotizing fascitis (34.4%) was the most common clinical presentation with anaerobic etiology followed by deep seated abscesses (23.4%). Conclusion: Anaerobic bacteria were isolated from a significant proportion of surgical infections. To avoid therapeutic failures, anaerobic bacteria in surgical infections need to be recognized by surgeons and laboratorians. PMID:27928485

Biodecolorization of Reactive Yellow-2 by Serratia sp. RN34 Isolated from Textile Wastewater.

PubMed

Najme, Rabia; Hussain, Sabir; Maqbool, Zahid; Imran, Muhammad; Mahmood, Faisal; Manzoor, Hamid; Yasmeen, Tahira; Shehzad, Tanvir

2015-12-01

Remediation of colored textile wastewaters is a matter of interest. In this study, 49 bacteria were isolated from the textile wastewater and tested for their ability to decolorize reactive yellow-2 (RY2) dye. The most efficient isolate, RN34, was identified through amplification, sequencing, and phylogenetic analysis of its 16S rDNA and was designated as Serratia sp. RN34. This bacterium was also found capable of decolorizing other related reactive azo-dyes, including reactive black-5, reactive red-120, and reactive orange-16 but at varying rates. The optimum pH for decolorization of RY2 by the strain RN34 was 7.5 using yeast extract as cosubstrate under static incubation at 30 °C. The strain RN34 also showed potential to decolorize RY2 in the presence of considerable amounts of hexavalent chromium and sodium chloride. A phytotoxicity study demonstrated relatively reduced toxicity of RY2 decolorized products on Vigna radiata plant as compared to the uninoculated RY2 solution.

Diversity of culturable psychrophilic and psychrotrophic anaerobic bacteria isolated from beef abattoirs and their environments.

PubMed

Moschonas, G; Bolton, D J; McDowell, D A; Sheridan, J J

2011-07-01

This study identified 431 psychrophilic or psychrotrophic isolates from commercial Irish beef abattoir environments and "blown packs" of vacuum-packed beef, using PCR and 16S rRNA sequencing, and estimated their intraspecies genetic diversity using restriction fragment length polymorphism (RFLP) analysis and spacer region PCR (SR-PCR). Twenty-five species were identified in the 431 isolates, with the most frequently recovered species being Clostridium gasigenes (n=315), Clostridium estertheticum (n=17), and a potentially novel species designated strain TC1 (n=52). These species were previously found to be associated with a particular type of spoilage known as blown-pack spoilage (BPS), which occurs in chilled-stored (i.e., -1.5°C to 4°C) vacuum-packaged meat within 2 to 4 weeks and involves the production of large volumes of gas. Overall, the study demonstrates the considerable and not previously reported diversity of the anaerobic microflora in abattoirs and the presence of a wide range of organisms capable of causing BPS at chilled temperatures.

Isolation and characterization of novel strains of Pseudomonas aeruginosa and Serratia marcescens possessing high efficiency to degrade gasoline, kerosene, diesel oil, and lubricating oil.

PubMed

Wongsa, Patcharaporn; Tanaka, Makiko; Ueno, Akio; Hasanuzzaman, Mohammad; Yumoto, Isao; Okuyama, Hidetoshi

2004-12-01

Bacteria possessing high capacity to degrade gasoline, kerosene, diesel oil, and lubricating oil were screened from several areas of Hokkaido, Japan. Among isolates, two strains, WatG and HokM, which were identified as new strains of Pseudomonas aeruginosa and Serratia marcescens species, respectively, showed relatively high capacity and wide spectrum to degrade the hydrocarbons in gasoline, kerosene, diesel, and lubricating oil. About 90-95% of excess amount of total diesel oil and kerosene added to mineral salts media as a sole carbon source could be degraded by WatG within 2 and 3 weeks, respectively. The same amount of lubricating oil was 60% degraded within 2 weeks. Strain HokM was more capable than WatG in degrading aromatic compounds in gasoline. This strain could also degrade kerosene, diesel, and lubricating oil with a capacity of 50-60%. Thus, these two isolates have potential to be useful for bioremediation of sites highly contaminated with petroleum hydrocarbons.

Aminobacter ciceronei sp. nov. and Aminobacter lissarensis sp. nov., isolated from various terrestrial environments

USGS Publications Warehouse

McDonald, I.R.; Kampfer, P.; Topp, E.; Warner, K.L.; Cox, M.J.; Connell, Hancock T.L.; Miller, L.G.; Larkin, M.J.; Ducrocq, V.; Coulter, C.; Harper, D.B.; Murrell, J.C.; Oremland, R.S.

2005-01-01

The bacterial strains IMB-1T and CC495T, which are capable of growth on methyl chloride (CH3Cl, chloromethane) and methyl bromide (CH3Br, bromomethane), were isolated from agricultural soil in California fumigated with CH3Br, and woodland soil in Northern Ireland, respectively. Two pesticide- /herbicide-degrading bacteria, strains ER2 and C147, were isolated from agricultural soil in Canada. Strain ER2 degrades N-methyl carbamate insecticides, and strain C147 degrades triazine herbicides widely used in agriculture. On the basis of their morphological, physiological and genotypic characteristics, these four strains are considered to represent two novel species of the genus Aminobacter, for which the names Aminobacter ciceronei sp. nov. (type strain IMB-1T=ATCC 202197T=CIP 108660T=CCUG 50580T; strains ER2 and C147) and Aminobacter lissarensis sp. nov. (type strain CC495T=NCIMB 13798T=CIP 108661T=CCUG 50579T) are proposed. ?? 2005 IUMS.

Diverse metal reduction and nano- mineral formation by metal-reducing bacteria enriched from inter-tidal flat sediments

NASA Astrophysics Data System (ADS)

Kim, Y.; Park, B.; Seo, H.; Roh, Y.

2009-12-01

Dissimilatory metal-reducing bacteria utilize diverse metal oxides as electron acceptors and couple this microbial metal reduciton to growth. However, the microbe-metal interactions playing important roles in the metal geochemistry and organic matter degradation in the tidal flat sediments have not been uncovered enough to employ in various environmental and industrial applications. The objective of this study was to examine biomineralization and bioremediation by the facultative metal-reducing bacteria isolated from the inter-tidal flat sediments in southwestern of Korea. 16S-rRNA analysis showed bacterial consortium mainly consists of genus of Clostridium sp. The enriched bacteria were capable of reducing diverse metals such as iron oxide, maganese oxide, Cr(VI) and Se(VI) during glucose fermentation process at room temperature. The bacteria reduced highly toxic and reactive elements such as Cr(VI) and Se(VI) to Cr(III) and Se(0). The results showed that microbial processes induced transformation from toxic states of heavy metals to less toxic and mobile states in natural environments. Andthe bacteria also reduced iron oxyhydroxide such as ferrihydrite and akaganeite (β-FeOOH) and formed nanometer-sized magnetite (Fe3O4). This study indicates microbial processes not only can be used for bioremediation of inorganic contaminants existing in the marine environments, but also form the magnetite nanoparticles which are exhibit superparamagnetic properties that can be useful for relevant medical and industrial applications.

[Screening and characterization of marine bacteria with antibacterial and cytotoxic activities, and existence of PKS I and NRPS genes in bioactive strains].

PubMed

Zhu, Peng; Zheng, Li; Li, Jing; Shao, Jian-zhong; Yan, Xiao-jun

2007-04-01

Antibacterial and cytotoxic activities were screened for marine bacteria which have been isolated from organism, sediments and seawater in China coastal area. The results showed that 42 isolates had antimicrobial activity and 12 isolates had cytotoxicity. Molecular phylogenetic analysis of marine bacteria with cytotoxicity based on 16S rRNA sequences indicated that they were belong to the genera Aerococcus, Agrobacterium, Alteromona, Bacillus, Exiguobacterium, Paracoccus, Pseudoalteromons, Rheinheimera. Furthermore, marine bacteria with cytotoxicity were also screened for PKS I and NRPS genes which could be responsible for bioactive secondary metabolites biosynthesis, 4 strains having KS domain or A domain were obtained, which provide strong evidence that marine bioactive bacteria can produce natural products through PKS and NRPS pathways.

Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: Characterization of the bacteriocin

PubMed Central

Furtado, Danielle N.; Todorov, Svetoslav D.; Landgraf, Mariza; Destro, Maria T.; Franco, Bernadette D.G.M.

2014-01-01

Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween 80, EDTA or NaCl. Bacteriocin production was dependent on the components of the culture media, especially nitrogen source and salts. When tested by PCR, the bacteriocin gene presented 100% homology to nisin Z gene. These properties indicate that this L. lactis subsp. lactis DF4Mi can be used for enhancement of dairy foods safety and quality. PMID:25763065

Aerobic bacterial microbiota isolated from the cloaca of the European pond turtle (Emys orbicularis) in Poland.

PubMed

Nowakiewicz, Aneta; Ziółkowska, Grażyna; Zięba, Przemysław; Dziedzic, Barbara Majer; Gnat, Sebastian; Wójcik, Mariusz; Dziedzic, Roman; Kostruba, Anna

2015-01-01

We conducted a comparative analysis of the aerobic cloacal bacteria of European pond turtles (Emys orbicularis) living in their natural environment and juvenile turtles reared under controlled conditions in a breeding center. We included 130 turtles in the study. The aerobic bacteria isolated from the cloaca of the juvenile turtles were less diverse and more prevalent than the bacteria isolated from free-living adults. We isolated 17 bacterial species from juvenile captive turtles, among which the dominant species were Cellulomonas flavigena (77/96), Enterococcus faecalis (96/96), Escherichia coli (58/96), and Proteus mirabilis (41/96). From the adult, free-living turtles, we isolated 36 bacterial species, some of which are a potential threat to public health (e.g., Salmonella enterica serovars Newport, Daytona, and Braenderup; Listeria monocytogenes; Yersinia enterocolitica; Yersinia ruckeri; Klebsiella pneumoniae; Vibrio fluvialis; and Serratia marcescens), and pathogens that are etiologic agents of diseases of ectothermic animals (e.g., Aeromonas sobria, Aeromonas caviae, Hafnia alvei, Edwardsiella tarda, and Citrobacter braakii; the last two species were isolated from both groups of animals). The cloacal bacterial biota of the European pond turtle was characterized by numerous species of bacteria, and its composition varied with turtle age and environmental conditions. The small number of isolated bacteria that are potential human pathogens may indicate that the European pond turtle is of relatively minor importance as a threat to public health.

Isolation, identification and characterization of indigenous fungi for bioremediation of hexavalent chromium, nickel and cobalt

NASA Astrophysics Data System (ADS)

Hernahadini, Nelis; Suhandono, Sony; Choesin, Devi N.; Chaerun, Siti K.; Kadarusman, Ade

2014-03-01

Waste from nickel mining of Sorowako in South Sulawesi contains hexavalent chromium, nickel and cobalt metals in high concentration and may have a negative impact to the environment. Common waste treatment systems such as chemical treatment using a reducing reagent may still have a negative impact. Bioremediation using fungi or bacteria becomes more popular because it is an environmentally friendly alternative. The purposes of this study are to isolate and identify indigenous fungi that are resistant to heavy metals (hexavalent chromium, nickel, and cobalt) and are capable of reducing the concentration of metals in mining wastes. Ten fungal isolates were successfully isolated from the soils and pond sediments in the area of nickel mining in Sorowako. Selection of superior isolate was carried out by growing all the isolates on PDA medium, which contained all of the three metals. One superior isolate was identified to be able to grow on medium with concentrations of 6400 ppm hexavalent chromium, 200 ppm nickel and 50 ppm cobalt. Molecular identification and phylogenetic studies of the isolate using fungal PCR primers developed to amplify the ITS (internal transcribed spacer) region showed that the isolate sequence was very close to Trichoderma atroviride with 99.8% similarity. Optimum incubation time for the uptake of hexavalent chromium was 3 days, nickel and cobalt was 5 days, respectively, with an optimum pH of 4.

Explanatory chapter: how plasmid preparation kits work.

PubMed

Koontz, Laura

2013-01-01

To isolate plasmid DNA from bacteria using a commercial plasmid miniprep kit (if interested, compare this protocol with Isolation of plasmid DNA from bacteria). Copyright © 2013 Elsevier Inc. All rights reserved.

Distribution and identification of proteolytic Bacillus spp. in paddy field soil under rice cultivation.

PubMed

Watanabe, K; Hayano, K

1993-07-01

Proteolytic bacteria in paddy field soils under rice cultivation were characterized and enumerated using azocoll agar plates. Bacillus spp. were the proteolytic bacteria that were most frequently present, comprising 59% of the isolates. They were always the numerically dominant proteolytic bacteria isolated from three kinds of fertilizer treatments (yearly application of rice-straw compost and chemical fertilizer, yearly application of chemical fertilizer, and no fertilizer application) and at three different stages of rice development (vegetative growth stage, maximal tillering stage, and harvest stage). Of the 411 proteolytic bacteria isolated, 124 isolates had stronger proteolytic activity than others on the basis of gelatin liquefaction tests and most of them were Bacillus spp. (100% in 1989 and 92.4% in 1991). Bacillus subtilis and Bacillus cereus were the main bacteria of this group and Bacillus mycoides, Bacillus licheniformis, and Bacillus megaterium were also present. We conclude that these Bacillus spp. are the primary source of soil protease in these paddy fields.

[The antagonistic properties of microaerophilic bacteria isolated from the human and mink digestive tracts].

PubMed

Sudenko, V I; Groma, L I; Podgorskiĭ, V S

1996-01-01

Study of antagonistic properties of microaerophilic bacteria isolated from human and mink gastroenteric tract have helped to establish differences in species composition, quantity and level of antagonistic activity of the studied microorganisms in respect to pathogenic microflora. It is shown that lactic acid bacteria identified as Lactobacillus fermentum and L. reuteri prevail among the strains isolated from the stomach and thin intestine of minks kept in the 30-km zone of Chernobyl NPP. Species composition of microaerophilic bacteria isolated from the digestive tract of the control minks is more variable. Antagonistically active bifidobacteria prevail in large intestine of experimental and control animals. Strains of lactic acid bacteria with the expressed antagonistic activity belonging to L. bavaricus, L. reuteri, L. coryniformis and L. maltaromicus have been found parallel with such known producers of antibiotic-like substances as L. fermentum. L. acidophilum. Streptococcus faecalis and bifidobacteria. L. maltaromicus most frequently occurred among antagonistically active strains revealed in feces of people which stayed in the zone of liquidation of the Chernobyl accident. Microaerophilic strains of bacteria (lactic acid, bifidobacteria and enterococci) manifest the expressed antagonistic activity connected with the capacity to not only acid formation but also to accumulation of antibiotic products of unknown nature. A strain of lactic acid bacteria L. fermentum 91 has been isolated from the contents of human gastroenteric tract. These bacteria are distinguished by most expressed and stable antagonism and characterized by the lack of pathogenicity in respect of albino mice that may be used to raise the microorganism resistance to gastric diseases.

Multidrug-resistant bacteria infection control: study of compliance with isolation precautions in a Paris university hospital.

PubMed

Vidal-Trecan, G M; Delamare, N; Tcherny-Lessenot, S; Lamory, J; Baudin, F; de Prittwitz, M; Salmon-Ceron, D

2001-02-01

Isolation practices in a university hospital were analyzed for 137 patients with multidrug-resistant bacteria. Isolation was ordered in writing by physicians for 40% and instituted by nurses for 60%; 74% were isolated. Compliance depended on physician ordering in writing (odds ratio, 36.3; 95% confidence interval, 4.8-274.9). Nurses complied best with hand washing.

Spoilage bacteria of fresh broiler chicken carcasses.

PubMed

Russell, S M; Fletcher, D L; Cox, N A

1995-12-01

Studies were conducted to identify the bacteria responsible for spoilage of fresh broiler chicken carcasses and to characterize the off-odors these bacteria produce. Broiler carcasses were collected from processing plants in the northeast Georgia area, the southeastern U.S., Arkansas, California, and North Carolina. The carcasses were allowed to spoil under controlled conditions at 3 C and spoilage bacteria were isolated. Each spoilage bacterium was separately inoculated into a sterile chicken skin medium, incubated at 25 C for 48 h, and subjectively evaluated for odor. The bacteria isolated from spoiled carcasses that consistently produced off-odors in the chicken skin medium, regardless of the geographical location from which the chickens were obtained, were Shewanella putrefaciens A, B, and D, Pseudomonas fluorescens A, B, and D, and Pseudomonas fragi. These bacteria produced off-odors that resembled "sulfur", "dishrag", "ammonia", "wet dog", "skunk", "dirty socks", "rancid fish", "unspecified bad odor", or a sweet smell resembling "canned corn". Odors produced by the spoilage bacteria were varied; however, odors most associated with spoiled poultry, such as "dishraggy" odors, were produced by the bacteria that were most consistently isolated, such as S. putrefaciens and the pseudomonads.

Diversity of bacteria associated with Bursaphelenchus xylophilus and other nematodes isolated from Pinus pinaster trees with pine wilt disease.

PubMed

Proença, Diogo Neves; Francisco, Romeu; Santos, Clara Vieira; Lopes, André; Fonseca, Luís; Abrantes, Isabel M O; Morais, Paula V

2010-12-09

The pinewood nematode (PWN), Bursaphelenchus xylophilus, has been thought to be the only causal agent of pine wilt disease (PWD), however, since bacteria have been suggested to play a role in PWD, it is important to know the diversity of the microbial community associated to it. This study aimed to assess the microbial community associated with B. xylophilus and with other nematodes isolated from pine trees, Pinus pinaster, with PWD from three different affected forest areas in Portugal. One hundred and twenty three bacteria strains were isolated from PWN and other nematodes collected from 14 P. pinaster. The bacteria strains were identified by comparative analysis of the 16S rRNA gene partial sequence. All except one gram-positive strain (Actinobacteria) belonged to the gram-negative Beta and Gammaproteobacteria. Most isolates belonged to the genus Pseudomonas, Burkholderia and to the family Enterobacteriaceae. Species isolated in higher percentage were Pseudomonas lutea, Yersinia intermedia and Burkholderia tuberum. The major bacterial population associated to the nematodes differed according to the forest area and none of the isolated bacterial species was found in all different forest areas. For each of the sampled areas, 60 to 100% of the isolates produced siderophores and at least 40% produced lipases. The ability to produce siderophores and lipases by most isolates enables these bacteria to have a role in plant physiological response. This research showed a high diversity of the microbial community associated with B. xylophilus and other nematodes isolated from P. pinaster with PWD.

Diversity of Bacteria Associated with Bursaphelenchus xylophilus and Other Nematodes Isolated from Pinus pinaster Trees with Pine Wilt Disease

PubMed Central

Proença, Diogo Neves; Francisco, Romeu; Santos, Clara Vieira; Lopes, André; Fonseca, Luís; Abrantes, Isabel M. O.; Morais, Paula V.

2010-01-01

The pinewood nematode (PWN), Bursaphelenchus xylophilus, has been thought to be the only causal agent of pine wilt disease (PWD), however, since bacteria have been suggested to play a role in PWD, it is important to know the diversity of the microbial community associated to it. This study aimed to assess the microbial community associated with B. xylophilus and with other nematodes isolated from pine trees, Pinus pinaster, with PWD from three different affected forest areas in Portugal. One hundred and twenty three bacteria strains were isolated from PWN and other nematodes collected from 14 P. pinaster. The bacteria strains were identified by comparative analysis of the 16S rRNA gene partial sequence. All except one Gram-positive strain (Actinobacteria) belonged to the Gram-negative Beta and Gammaproteobacteria. Most isolates belonged to the genus Pseudomonas, Burkholderia and to the family Enterobacteriaceae. Species isolated in higher percentage were Pseudomonas lutea, Yersinia intermedia and Burkholderia tuberum. The major bacterial population associated to the nematodes differed according to the forest area and none of the isolated bacterial species was found in all different forest areas. For each of the sampled areas, 60 to 100% of the isolates produced siderophores and at least 40% produced lipases. The ability to produce siderophores and lipases by most isolates enables these bacteria to have a role in plant physiological response. This research showed a high diversity of the microbial community associated with B. xylophilus and other nematodes isolated from P. pinaster with PWD. PMID:21151611

Isolation and identification of local bacteria endophyte and screening of its antimicrobial property against pathogenic bacteria and fungi

NASA Astrophysics Data System (ADS)

Fikri, Ahmad Syairazie Ibrahim; Rahman, Irman Abdul; Nor, Norefrina Shafinaz Md; Hamzah, Ainon

2018-04-01

Endophytes are organisms, often fungi and bacteria that live in living plant cells. These organisms reside in the living tissues of the host plant in a variety of relationships, ranging from symbiotic to slightly pathogenic. The endophytes may produce a plethora of substances that have potential to be used in modern medicine, agriculture and industry. The aims of this study are to isolate, identify and screening antimicrobial activity of bacterial endophytes. The endophytes were isolated using nutrient agar, incubated at 37°C for 48 hours. Identification of the isolates were done based on morphological characteristics, biochemical tests and 16S rDNA molecular analysis. Disk diffusion method was used to screen for antimicrobial activity of metabolites from endophytes against pathogenic bacteria. Screening for antifungal activity of selected endophytes was done using dual culture method againts pathogenic fungi followed by Kirby-Bauer method. Results showed endophytes designated as B2c and B7b have positive antimicrobial activity. The metabolites from isolate B2c showed antimicrobial activity against pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Staphylococcus epidermis, while isolate B7b have positive activities againts MRSA, S. aureus and Pseudomonas aeruginosa. Isolates B2c displayed antifungal activity against Fusarium oxysporum, Fusarium solani, Phytophthora palmivora and Colletotrichum gloeosporioides. Identification using biochemical tests and 16S rDNA sequences identified isolate B2c as Pseudomonas resinovorans with 97% homology and isolate B7b as Bacillus subtilis with 98% homology.

The potential for Probiotic Bacteria from milkfish intestine in reducing mercury metals in skimmed milk media

NASA Astrophysics Data System (ADS)

Dwyana, Zaraswati; Priosambodo, D.; Haedar, N.; Erviani, A. E.; Djabura, A. K.; Sukma, R.

2018-03-01

Mercury (Hg) is one of the heavy metals that is harmful to humans. The accumulation of mercury in the body is generally derived from food. Several types of bacteria from intestine of milkfish are known to reduce mercury concentration. People can take advantage of this bacterial ability by eating it through probiotic foods. This research conducted to figure out the potential for probiotic bacteria from milkfish intestine in reducing mercury. Isolation from probiotic bacteria from milkfish intestine conducted with grown the isolates in MRSA medium with addition of 1% CaCO3. Twelve isolate were obtained from milkfish intestine. Mercury resistance tested was performed by measuring cell density using a spectrophotometer at concentrations of 10, 15 and 20 ppm respectively in skim milk media. Probiotic tests (gastric acid, bile salts and antimicrobial activity) for MRSB media was also conducted. Results showed that seven isolate were resistant to mercury in all concentrations and potential as probiotics. All resistant isolate then tested for skim milk media with addition of 5, 10, 20 ppm mercury acetate respectively. Result showed that only one isolated was able to reduce the concentration of mercury (Hg) in all variations on concentration and potential as mercury reducer probiotic bacteria.

[Isolation, identification and characterization of ACC deaminase-containing endophytic bacteria from halophyte Suaeda salsa].

PubMed

Teng, Songshan; Liu, Yanping; Zhao, Lei

2010-11-01

We Isolated and characterized 1-aminocyclopropane-1-carboxylate (ACC) deaminase-containing endophytic bacteria from halophyte Suaeda salsa to understand the interactions between endophytes and halophyte. ACC deaminase-containing endophytic bacteria were isolated from root, stalk and leaf of Suaeda salsa and were identified based on morphological, physiological-biochemical properties, API and 16S rRNA sequence analysis. Isolates were evaluated for their ACC deaminase, antifungal, protease activity, siderophores and phytohormones, such as indole-3-acetic acid, gibberellic acid and abscisic acid production, as well as atmospheric nitrogen fixation and phosphate solubilization. Four ACC deaminase-containing endophytic bacteria strains named as LP11, SS12, TW1 and TW2 were isolated and identified as Pseudomonas oryzihabitans, Pseudomonas sp., Pantoea agglomerans and Pseudomonas putida respectively. All the strains possessed the phosphate-solubilizing ability and could produce siderophores and phytohormones more or less. None of them could fix atmospheric nitrogen or produce protease. Only strain SS12 showed antagonism against two phytopathogenic fungi viz Fusarium oxysporum f. sp. conglutinans and F. oxysporum f. sp. cucumerinum. ACC deaminase-containing endophytic bacteria of Pseudomonas sp. and Pantoea sp. isolated from halophyte Suaeda salsa have abundant biological characteristics related to plant growth promotion, stress homeostasis regulation and biocontrol activity.

Screening and characterization of thermo-active enzymes of biotechnological interest produced by thermophilic Bacillus isolated from hot springs in Tunisia.

PubMed

Thebti, Wajdi; Riahi, Yosra; Gharsalli, Rawand; Belhadj, Omrane

2016-01-01

As part of the contribution to the global efforts in research of thermostable enzymes being of industrial interest, we focus on the isolation of thermophilic bacteria from Tunisian hot springs. Among the collection of 161 strains of thermophilic Bacillus isolated from different samples of thermal water in Tunisia, 20% are capable of growing at 100°C and the rest grow at 70°C or above. Preliminary activity tests on media supplemented with enzyme-substrates confirmed that 35 strains produced amylases, 37 - proteases, 43 - cellulases, 31 - xylanases and 37 - mannanases. The study of the effect of temperature on enzyme activity led to determination of the optimal temperatures of activities that vary between 60 and 100°C. Several enzymes were active at high temperatures (80, 90 and 100°C) and kept their activity even at 110°C. Several isolated strains producing enzymes with high optimal temperatures of activity were described for the first time in this study. Both strains B62 and B120 are producers of amylase, protease, cellulase, xylanase, and mannanase. The sequencing of 16S DNA identified isolated strains as Geobacillus kaustophillus, Aeribacillus pallidus, Geobacillus galactosidasus and Geobacillus toebii.

Luminous bacteria cultured from fish guts in the Gulf of Oman.

PubMed

Makemson, J C; Hermosa, G V

1999-01-01

The incidence of culturable luminous bacteria in Omani market fish guts was correlated to habitat type amongst 109 species of fish. Isolated representative luminous bacteria were compared to known species using the Biolog system (95 traits/isolate) and cluster analysis, which showed that the main taxa present in fish guts were clades related to Vibrio harveyi and Photobacterium species with sporadic incidence of P. phosphoreum. The luminous isolates from gut of the slip-mouth (barred pony fish), Leiognathus fasciatus, were mainly a type related to Photobacterium but phenotypically different from known species. These luminous gut bacteria were identical with the bacteria in the light organ, indicating that the light organ supplies a significant quantity of luminous bacteria to the gut. In many of the fish that lack light organs, luminous bacteria were also the dominant bacterial type in the gut, while in some others luminous bacteria were encountered sporadically and at low densities, reflecting the incidence of culturable luminous bacteria in seawater. Pelagic fish contained the highest incidence of culturable luminous bacteria and reef-associated fish the lowest. No correlation was found between the incidence of culturable luminous bacteria and the degree to which fish produce a melanin-covered gut. Copyright 1999 John Wiley & Sons, Ltd.

Structurally altered capsular polysaccharides produced by mutant bacteria

NASA Technical Reports Server (NTRS)

Petersen, Gene R. (Inventor); Kern, Roger G. (Inventor); Richards, Gil F. (Inventor)

1995-01-01

Structurally altered capsular polysaccharides are produced by mutant bacteria. These polysaccharides are isolated by selecting a wild type bacterial strain and a phage producing degradative enzymes that have substrate specificity for the capsular polysaccharides produced by the wild type bacteria. Phage-resistant mutants producing capsular polysaccharides are selected and the structurally altered capsular polysaccharide is isolated therefrom.

Screening of endophytic bacteria isolated from two kinds of antarctic plant antagonistic konjac soft rot disease

NASA Astrophysics Data System (ADS)

Gong, Mingfu; Lin, Tianxing; Huang, Jiao; Zeng, Bo

2018-04-01

Konjac soft rot has a serious impact on the production of konjac, the use of endophytic bacteria to inhibit konjac soft rot bacteria have many advantages. Twenty-three endophytic bacteria isolated from the medicinal plants were used to determine the antagonistic effects of endophytic bacteria on konjac soft rot in the Oxford cups. Of the strain. The results showed that 23 strains of endophytic bacteria had different antagonistic activities against konjac soft rot, 8 strains had very significant antibacterial effect, and YC06 and YC09 had strong antibacterial ability of two endophytic bacteria. Konjac soft rot fungi also have a strong antibacterial capacity.

Linking Mn(II)-oxidizing bacteria to natural attenuation at a former U mining site

NASA Astrophysics Data System (ADS)

Akob, D.; Bohu, T.; Beyer, A.; Schäffner, F.; Händel, M.; Johnson, C.; Merten, D.; Büchel, G.; Totsche, K.; Küsel, K.

2012-04-01

Uranium mining near Ronneburg, Germany resulted in widespread environmental contamination with acid mine drainage (AMD) and high concentrations of heavy metals and radionuclides. Despite physical remediation of the area, groundwater is still a source of heavy metal contaminants, e.g., Cd, Ni, Co, Cu and Zn, to nearby ecosystems. However, natural attenuation of heavy metals is occurring in Mn oxide rich soils and sediments ranging in pH from 5 to 7. While microorganisms readily oxidize Mn(II) and precipitate Mn oxides at pH ~7 under oxic conditions, few studies describe Mn(II)-oxidizing bacteria (MOB) at pH ~5 and/or in the presence of heavy metals. In this study we (1) isolated MOB from the contaminated Ronneburg area at pH 5.5 and 7 and (2) evaluated the biological formation of Mn oxides. We isolated nine MOB strains at pH 7 (members of the Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes phyla) and a single isolate at pH 5.5 (Oxalobacteraceae isolate AB_14, within the β-Proteobacteria). LA-ICP-MS showed that all isolates accumulated Mn and Fe in their biomass. However, the Oxalobacteraceae isolate AB_14 oxidizes more Mn without additional Fe in the medium. Preliminary FTIR analysis indicated that all isolates formed precipitates, which showed absorption bands that were characteristic for birnessite. High resolution TEM showed variable morphology of precipitates and EDS confirmed the presence of Mn oxides. Isolate AB_14 was not surrounded with precipitates whereas our Actinobacteria isolate AB_18 was encrusted with Mn oxides. Electron diffraction is currently being used to confirm the presence of birnessite and other Mn oxide phases. This, the first known report of any organism capable of Mn oxidation at low pH, demonstrated that MOB can be involved in the natural attenuation of both moderately acidic and neutral pH soils and sediments via the formation of biogenic Mn oxides. Future work will fully evaluate the minerals formed in this process as well as their interactions with contaminating heavy metals and radionuclides.

Metagenomic analysis of nitrate-reducing bacteria in the oral cavity: implications for nitric oxide homeostasis.

PubMed

Hyde, Embriette R; Andrade, Fernando; Vaksman, Zalman; Parthasarathy, Kavitha; Jiang, Hong; Parthasarathy, Deepa K; Torregrossa, Ashley C; Tribble, Gena; Kaplan, Heidi B; Petrosino, Joseph F; Bryan, Nathan S

2014-01-01

The microbiota of the human lower intestinal tract helps maintain healthy host physiology, for example through nutrient acquisition and bile acid recycling, but specific positive contributions of the oral microbiota to host health are not well established. Nitric oxide (NO) homeostasis is crucial to mammalian physiology. The recently described entero-salivary nitrate-nitrite-nitric oxide pathway has been shown to provide bioactive NO from dietary nitrate sources. Interestingly, this pathway is dependent upon oral nitrate-reducing bacteria, since humans lack this enzyme activity. This pathway appears to represent a newly recognized symbiosis between oral nitrate-reducing bacteria and their human hosts in which the bacteria provide nitrite and nitric oxide from nitrate reduction. Here we measure the nitrate-reducing capacity of tongue-scraping samples from six healthy human volunteers, and analyze metagenomes of the bacterial communities to identify bacteria contributing to nitrate reduction. We identified 14 candidate species, seven of which were not previously believed to contribute to nitrate reduction. We cultivated isolates of four candidate species in single- and mixed-species biofilms, revealing that they have substantial nitrate- and nitrite-reduction capabilities. Colonization by specific oral bacteria may thus contribute to host NO homeostasis by providing nitrite and nitric oxide. Conversely, the lack of specific nitrate-reducing communities may disrupt the nitrate-nitrite-nitric oxide pathway and lead to a state of NO insufficiency. These findings may also provide mechanistic evidence for the oral systemic link. Our results provide a possible new therapeutic target and paradigm for NO restoration in humans by specific oral bacteria.

Metagenomic Analysis of Nitrate-Reducing Bacteria in the Oral Cavity: Implications for Nitric Oxide Homeostasis

PubMed Central

Hyde, Embriette R.; Andrade, Fernando; Vaksman, Zalman; Parthasarathy, Kavitha; Jiang, Hong; Parthasarathy, Deepa K.; Torregrossa, Ashley C.; Tribble, Gena; Kaplan, Heidi B.; Petrosino, Joseph F.; Bryan, Nathan S.

2014-01-01

The microbiota of the human lower intestinal tract helps maintain healthy host physiology, for example through nutrient acquisition and bile acid recycling, but specific positive contributions of the oral microbiota to host health are not well established. Nitric oxide (NO) homeostasis is crucial to mammalian physiology. The recently described entero-salivary nitrate-nitrite-nitric oxide pathway has been shown to provide bioactive NO from dietary nitrate sources. Interestingly, this pathway is dependent upon oral nitrate-reducing bacteria, since humans lack this enzyme activity. This pathway appears to represent a newly recognized symbiosis between oral nitrate-reducing bacteria and their human hosts in which the bacteria provide nitrite and nitric oxide from nitrate reduction. Here we measure the nitrate-reducing capacity of tongue-scraping samples from six healthy human volunteers, and analyze metagenomes of the bacterial communities to identify bacteria contributing to nitrate reduction. We identified 14 candidate species, seven of which were not previously believed to contribute to nitrate reduction. We cultivated isolates of four candidate species in single- and mixed-species biofilms, revealing that they have substantial nitrate- and nitrite-reduction capabilities. Colonization by specific oral bacteria may thus contribute to host NO homeostasis by providing nitrite and nitric oxide. Conversely, the lack of specific nitrate-reducing communities may disrupt the nitrate-nitrite-nitric oxide pathway and lead to a state of NO insufficiency. These findings may also provide mechanistic evidence for the oral systemic link. Our results provide a possible new therapeutic target and paradigm for NO restoration in humans by specific oral bacteria. PMID:24670812

Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria.

PubMed

Gilardi, G L; Faur, Y C

1984-10-01

Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. The remaining seven strains represented an undescribed taxon. These pink bacteria appear to be invaders of debilitated patients with an underlying chronic disease.

Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria.

PubMed Central

Gilardi, G L; Faur, Y C

1984-01-01

Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. The remaining seven strains represented an undescribed taxon. These pink bacteria appear to be invaders of debilitated patients with an underlying chronic disease. PMID:6490848

Isolation of Brucella inopinata-Like Bacteria from White's and Denny's Tree Frogs.

PubMed

Kimura, Masanobu; Une, Yumi; Suzuki, Michio; Park, Eun-Sil; Imaoka, Koichi; Morikawa, Shigeru

2017-05-01

Brucella inopinata strain BO1 and B. sp. strain BO2 isolated from human patients, respectively, are genetically different from classical Brucella species. We isolated bacteria of the genus Brucella from two species of wild-caught tropical frogs kept in the facilities in Japan: White's tree frog, which inhabits Oceania, and Denny's tree frog, which inhabits Southeast Asia. Phylogenetic analyses based on 16S rRNA and recA gene sequences and multilocus sequence analysis showed that two isolates of Brucella spp. showed significant similarity to BO1, BO2, and the isolates from other wild-caught frogs. These results suggest that a variety of frog species are susceptible to a novel clade of Brucella bacteria, including B. inopinata.

Antibiotic resistance of native and faecal bacteria isolated from rivers, reservoirs and sewage treatment facilities in Victoria, south-eastern Australia.

PubMed

Boon, P I; Cattanach, M

1999-03-01

The incidence of resistance to ampicillin, chloramphenicol, kanamycin, nalidixic acid, neomycin and streptomycin was significantly greater (P < 0.001) in native heterotrophic bacteria than in Escherichia coli isolated from a range of sites along the Yarra River in south-eastern Australia. There was no significant difference in the incidence of resistance between native and faecal bacteria to tetracycline. Both groups were almost totally resistant to penicillin. Multivariate analyses indicated little clear spatial pattern in the incidence of resistance in native bacteria from upstream vs downstream sites along the Yarra River. In contrast, E. coli isolated from upstream (rural) sites tended to have a lower incidence of resistance than isolates from downstream (urban) sites. These findings have implications for the use of antibiotic resistance as a bacteriological water quality parameter.

Association of metal tolerance with multiple antibiotic resistance of bacteria isolated from drinking water.

PubMed

Calomiris, J J; Armstrong, J L; Seidler, R J

1984-06-01

Bacterial isolates from the drinking water system of an Oregon coastal community were examined to assess the association of metal tolerance with multiple antibiotic resistance. Positive correlations between tolerance to high levels of Cu2+, Pb2+, and Zn2+ and multiple antibiotic resistance were noted among bacteria from distribution waters but not among bacteria from raw waters. Tolerances to higher levels of Al3+ and Sn2+ were demonstrated more often by raw water isolates which were not typically multiple antibiotic resistant. A similar incidence of tolerance to Cd2+ was demonstrated by isolates of both water types and was not associated with multiple antibiotic resistance. These results suggest that simultaneous selection phenomena occurred in distribution water for bacteria which exhibited unique patterns of tolerance to Cu2+, Pb2+, and Zn2+ and antibiotic resistance.

Phylogeny and Antagonistic Activities of Culturable Bacteria Associated with the Gut Microbiota of the Sea Urchin (Paracentrotus lividus).

PubMed

Laport, Marinella Silva; Bauwens, Mathieu; Collard, Marie; George, Isabelle

2018-03-01

In this study, we have investigated the phylogeny and the antagonistic interactions of culturable bacteria isolated from the sea urchin Paracentrotus lividus collected from Aber and Morgat, both located in Crozon peninsula, France. Bacteria were isolated from the gastrointestinal tracts of ten specimens by using conventional culture-dependent method and then investigated by using phylogenetic analysis based on 16S rRNA gene sequence comparisons. Assays for antagonistic interactions among the bacterial strains were performed; bacteria (including at least one strain representative of each OTU identified) were screened for antimicrobial substance production. So, 367 bacterial strains were isolated on marine-agar. On the basis of morphological characteristics, 180 strains were sequenced and 94 OTUs were classified. The dominant phyla were Proteobacteria, Firmicutes and Actinobacteria, with a high abundance of the strains belonging to the genus Psychrobacter. From the antagonistic interactions assays, it could be determined that 22.7% strains were positive for at least one antagonism interaction, 18.3% of them isolated from the sea urchins collected in Morgat. We hypothesize that the bacteria isolated in this study may represent the transitory microbiota of the gastrointestinal tract of P. lividus, and that this microbiota may be related to the diet of this marine invertebrate. Furthermore, our results suggest that chemical antagonism could play a significant role in shaping the bacterial communities within gastrointestinal tract of the sea urchins. In addition, most isolated bacteria may have promising biotechnology applications.

Genetically engineered acidophilic heterotrophic bacteria by bacteriophage transduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, T.E.; Bruhn, D.F.; Bulmer, D.F.

1989-05-10

A bacteriophage capable of infecting acidophilic heterotrophic bacteria and processes for genetically engineering acidophilic bacteria for biomining or sulfur removal from coal are disclosed. The bacteriophage is capable of growth in cells existing at pH at or below 3.0. Lytic forms of the phage introduced into areas experiencing acid drainage kill the bacteria causing such drainage. Lysogenic forms of the phage having genes for selective removal of metallic or nonmetallic elements can be introduced into acidophilic bacteria to effect removal of the desired element from ore or coal. 1 fig., 1 tab.

Incidence of Carbapenem-Resistant Gram Negatives in Italian Transplant Recipients: A Nationwide Surveillance Study

PubMed Central

Lanini, Simone; Costa, Alessandro Nanni; Puro, Vincenzo; Procaccio, Francesco; Grossi, Paolo Antonio; Vespasiano, Francesca; Ricci, Andrea; Vesconi, Sergio; Ison, Michael G.; Carmeli, Yehuda; Ippolito, Giuseppe

2015-01-01

Background Bacterial infections remain a challenge to solid organ transplantation. Due to the alarming spread of carbapenem-resistant gram negative bacteria, these organisms have been frequently recognized as cause of severe infections in solid organ transplant recipients. Methods and Findings Between 15 May and 30 September 2012 we enrolled 887 solid organ transplant recipients in Italy with the aim to describe the epidemiology of gram negative bacteria spreading, to explore potential risk factors and to assess the effect of early isolation of gram negative bacteria on recipients’ mortality during the first 90 days after transplantation. During the study period 185 clinical isolates of gram negative bacteria were reported, for an incidence of 2.39 per 1000 recipient-days. Positive cultures for gram negative bacteria occurred early after transplantation (median time 26 days; incidence rate 4.33, 1.67 and 1.14 per 1,000 recipient-days in the first, second and third month after SOT, respectively). Forty-nine of these clinical isolates were due to carbapenem-resistant gram negative bacteria (26.5%; incidence 0.63 per 1000 recipient-days). Carbapenems resistance was particularly frequent among Klebsiella spp. isolates (49.1%). Recipients with longer hospital stay and those who received either heart or lung graft were at the highest risk of testing positive for any gram negative bacteria. Moreover recipients with longer hospital stay, lung recipients and those admitted to hospital for more than 48h before transplantation had the highest probability to have culture(s) positive for carbapenem-resistant gram negative bacteria. Forty-four organ recipients died (0.57 per 1000 recipient-days) during the study period. Recipients with at least one positive culture for carbapenem-resistant gram negative bacteria had a 10.23-fold higher mortality rate than those who did not. Conclusion The isolation of gram-negative bacteria is most frequent among recipient with hospital stays >48 hours prior to transplant and in those receiving either heart or lung transplants. Carbapenem-resistant gram negative isolates are associated with significant mortality. PMID:25835018

Production of halomethanes and isoprene in the culture of bacteria isolated from brackish water

NASA Astrophysics Data System (ADS)

Fujimori, T.; Taniai, G.; Kurihara, M.; Tamegai, H.; Hashimoto, S.

2010-12-01

Halomethanes produced naturally are important source of halogen in troposphere and stratosphere. In the ocean, macroalgae and phytoplankton have been considered to be the main producers of halomethanes. Recent investigations have shown that marine bacteria also produces halomethane such as iodomethane. However, knowledge of aquatic halomethane production, especially by bacteria, is insufficient. Here we survey bacteria, which produce volatile organic compounds (VOCs) including halomethanes, from brackish area (salinity: about 5‰) where high halomethane productions were observed. Bacteria was isolated and incubated in marine broth 2216, which is the media for marine bacteria. The VOCs such as halomethanes in the gas phase above cultured samples was determined using dynamic headspace (GESTEL DHS) - gas chromatograph (Agilent 6890N)- mass spectrometer (Agilent 5975C). The optical density at 600 nm (OD600) was also measured during the cultured period. From the result of the isolation and measurement of VOCs, some of the isolated bacteria produced halomethanes. For example, monohalomethanes (from 1 to about 600 nM) and isoprene (up to about 400 nM) were increased for several days in the culture (dibromomethane, chloroiodomethane, bromoiodomethane, and tribromomethane were not detected). Since halomethanes are abundant at the sampling point (under 1% of light intensity of the surface), bacteria is one of the possible candidates for halomethane producer there. Now, we are studying on the identification by 16S rRNA sequence analysis of bacteria collected from brackish water.

Phylloplane bacteria increase seedling emergence, growth and yield of field-grown groundnut (Arachis hypogaea L.).

PubMed

Kishore, G K; Pande, S; Podile, A R

2005-01-01

To isolate and characterize groundnut-associated bacterial isolates for growth promotion of groundnut in field. Three hundred and ninety-three groundnut-associated bacteria, representing the geocarposphere, phylloplane and rhizosphere, and endophytes were applied as seed treatment in greenhouse. Maximum increase in plant biomass (up to 26%) was observed following treatment with a rhizosphere isolate identified as Bacillus firmis GRS 123, and two phylloplane isolates Bacillus megaterium GPS 55 and Pseudomonas aeruginosa GPS 21. There was no correlation between the production of L-tryptophan-derived auxins and growth promotion by the test isolates. Actively growing cells and peat formulations of GRS 123 and GPS 55, and actively growing cells of GPS 21, significantly increased the plant growth and pod yield (up to 19%) in field. Rifampicin-resistant mutants of GRS 123 and GPS 21 colonized the ecto- and endorhizospheres of groundnut, respectively, up to 100 days after sowing (DAS), whereas GPS 55 was recovered from both the habitats at 100 DAS. Seed bacterization with phylloplane isolates promoted groundnut growth indicating the possibility of isolating rhizosphere beneficial bacteria from different habitats. Identification of phylloplane bacteria as effective plant growth-promoting rhizobacteria (PGPR) broadens the spectrum of PGPR available for field application.

The antagonistic activity of lactic acid bacteria isolated from peda, an Indonesian traditional fermented fish

NASA Astrophysics Data System (ADS)

Putra, T. F.; Suprapto, H.; Tjahjaningsih, W.; Pramono, H.

2018-04-01

Peda is an Indonesian traditional fermented whole fish prepared by addition of salt prior to fermentation and drying process. Salt used to control the growth of the lactic acid bacteria for the fermentation process. The objectives of this study were isolating and characterize the potential lactic acid bacteria (LAB) from peda as culture starter candidate, particularly its activity against pathogenic bacteria. A total of five samples from five regions of East Java Province was collected and subjected to LAB isolation. Fifty-seven of 108 colonies that show clear zone in de Man, Rogosa and Sharpe (MRS) agar supplemented with 0.5% CaCO3 were identified as LAB. Twenty-seven of the LAB isolates were exhibit inhibition against Staphylococcus aureus ATCC 6538 and Pseudomonas aeruginosa ATCC 27853. Isolate Aerococcus NJ-20 was exhibited strong inhibition against S. aureus ATCC 6538 (7.6 ± 1.35 mm inhibition zone) but was not produce bacteriocin. This finding suggests that the isolate Aerococcus NJ-20 can be applied as biopreservative culture starter on peda production. Further analysis on technological properties of isolates will be needed prior to application.

Occurrence of Multidrug Resistant Extended Spectrum Beta-Lactamase-Producing Bacteria on Iceberg Lettuce Retailed for Human Consumption.

PubMed

Bhutani, Natasha; Muraleedharan, Chithra; Talreja, Deepa; Rana, Sonia Walia; Walia, Sandeep; Kumar, Ashok; Walia, Satish K

2015-01-01

Antibiotic resistance in bacteria is a global problem exacerbated by the dissemination of resistant bacteria via uncooked food, such as green leafy vegetables. New strains of bacteria are emerging on a daily basis with novel expanded antibiotic resistance profiles. In this pilot study, we examined the occurrence of antibiotic resistant bacteria against five classes of antibiotics on iceberg lettuce retailed in local convenience stores in Rochester, Michigan. In this study, 138 morphologically distinct bacterial colonies from 9 iceberg lettuce samples were randomly picked and tested for antibiotic resistance. Among these isolates, the vast majority (86%) demonstrated resistance to cefotaxime, and among the resistant bacteria, the majority showed multiple drug resistance, particularly against cefotaxime, chloramphenicol, and tetracycline. Three bacterial isolates (2.17%) out of 138 were extended spectrum beta-lactamase (ESBL) producers. Two ESBL producers (T1 and T5) were identified as Klebsiella pneumoniae, an opportunistic pathogen with transferable sulfhydryl variable- (SHV-) and TEM-type ESBLs, respectively. The DNA sequence analysis of the bla SHV detected in K. pneumoniae isolate T1 revealed 99% relatedness to bla SHV genes found in clinical isolates. This implies that iceberg lettuce is a potential reservoir of newly emerging and evolving antibiotic resistant bacteria and its consumption poses serious threat to human health.

Isolation of Viable but Non-culturable Bacteria from Printing and Dyeing Wastewater Bioreactor Based on Resuscitation Promoting Factor.

PubMed

Jin, Yi; Gan, Guojuan; Yu, Xiaoyun; Wu, Dongdong; Zhang, Li; Yang, Na; Hu, Jiadan; Liu, Zhiheng; Zhang, Lixin; Hong, Huachang; Yan, Xiaoqing; Liang, Yan; Ding, Linxian; Pan, Yonglong

2017-07-01

Printing and dyeing wastewater with high content of organic matters, high colority, and poor biochemical performance is hard to be degraded. In this study, we isolated viable but non-culturable (VBNC) bacteria from printing and dyeing wastewater with the culture media contained resuscitation promoting factor (Rpf) protein secreted by Micrococcus luteus, counted the culturable cells number with the most probable number, sequenced 16S rRNA genes, and performed polymerase chain reaction-denaturing gradient gel electrophoresis. It is obviously that the addition of Rpf in the enrichment culture could promote growth and resuscitation of bacteria in VBNC state to obtain more fastidious bacteria significantly. The identified bacteria were assigned to nine genera in the treatment group, while the two strains of Ochrobactrum anthropi and Microbacterium sp. could not be isolated from the control group. The function of isolated strains was explored and these strains could degrade the dye of Congo red. This study provides a new sight into the further study including the present state, composition, formation mechanism, and recovery mechanism about VBNC bacteria in printing and dyeing wastewater, which would promote to understand bacterial community in printing and dyeing wastewater, and to obtain VBNC bacteria from ecological environment.

Occurrence of Multidrug Resistant Extended Spectrum Beta-Lactamase-Producing Bacteria on Iceberg Lettuce Retailed for Human Consumption

PubMed Central

Talreja, Deepa; Rana, Sonia Walia; Walia, Sandeep; Walia, Satish K.

2015-01-01

Antibiotic resistance in bacteria is a global problem exacerbated by the dissemination of resistant bacteria via uncooked food, such as green leafy vegetables. New strains of bacteria are emerging on a daily basis with novel expanded antibiotic resistance profiles. In this pilot study, we examined the occurrence of antibiotic resistant bacteria against five classes of antibiotics on iceberg lettuce retailed in local convenience stores in Rochester, Michigan. In this study, 138 morphologically distinct bacterial colonies from 9 iceberg lettuce samples were randomly picked and tested for antibiotic resistance. Among these isolates, the vast majority (86%) demonstrated resistance to cefotaxime, and among the resistant bacteria, the majority showed multiple drug resistance, particularly against cefotaxime, chloramphenicol, and tetracycline. Three bacterial isolates (2.17%) out of 138 were extended spectrum beta-lactamase (ESBL) producers. Two ESBL producers (T1 and T5) were identified as Klebsiella pneumoniae, an opportunistic pathogen with transferable sulfhydryl variable- (SHV-) and TEM-type ESBLs, respectively. The DNA sequence analysis of the bla SHV detected in K. pneumoniae isolate T1 revealed 99% relatedness to bla SHV genes found in clinical isolates. This implies that iceberg lettuce is a potential reservoir of newly emerging and evolving antibiotic resistant bacteria and its consumption poses serious threat to human health. PMID:26064922

Characterization of some bacteriocins produced by lactic acid bacteria isolated from fermented foods.

PubMed

Grosu-Tudor, Silvia-Simona; Stancu, Mihaela-Marilena; Pelinescu, Diana; Zamfir, Medana

2014-09-01

Lactic acid bacteria (LAB) isolated from different sources (dairy products, fruits, fresh and fermented vegetables, fermented cereals) were screened for antimicrobial activity against other bacteria, including potential pathogens and food spoiling bacteria. Six strains have been shown to produce bacteriocins: Lactococcus lactis 19.3, Lactobacillus plantarum 26.1, Enterococcus durans 41.2, isolated from dairy products and Lactobacillus amylolyticus P40 and P50, and Lactobacillus oris P49, isolated from bors. Among the six bacteriocins, there were both heat stable, low molecular mass polypeptides, with a broad inhibitory spectrum, probably belonging to class II bacteriocins, and heat labile, high molecular mass proteins, with a very narrow inhibitory spectrum, most probably belonging to class III bacteriocins. A synergistic effect of some bacteriocins mixtures was observed. We can conclude that fermented foods are still important sources of new functional LAB. Among the six characterized bacteriocins, there might be some novel compounds with interesting features. Moreover, the bacteriocin-producing strains isolated in our study may find applications as protective cultures.

Bacteria profile and antibiogram of the bacteria isolated from the exposed pulp of dog canine teeth.

PubMed

Almansa Ruiz, José Carlos; Jonker, Annelize; Bosman, Anna-Mari; Steenkamp, Gerhard

2018-04-27

Twenty-seven microbiological samples were taken from root canals (RC) of the canine teeth of 20 dogs where the pulps were non-vital and exposed due to complicated crown fractures. These pulps were cultured for aerobic/anaerobic bacteria. Antimicrobial susceptibility of isolates was determined using the Kirby-Bauer diffusion test. A total of 49 cultivable isolates, belonging to 27 different microbial species and 18 different genera, were recovered from the 27 RCs sampled. Twenty (40.81 per cent) of the cultivable isolates were Gram positive while 29 (59.19 per cent) were Gram negative. Facultative anaerobes were the most common bacteria (77.56 per cent). Aerobic isolates represented 18.36 per cent, and strict anaerobes 4.08 per cent. The antimicrobials with the highest in vitro efficacy were gentamicin (100 per cent) and enrofloxacin (93.32 per cent). © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Bacteria contributing to behaviour of radiocarbon in sodium acetate.

PubMed

Ishii, Nobuyoshi; Uchida, Shigeo

2011-07-01

An acetate-utilising bacterium was isolated and identified from deionised water that was used for flooding of paddy soils in this study's batch culture experiments. Bacteria in the deionised water samples formed colonies on agar plates containing [1,2-(14)C] sodium acetate, and the autoradiograms showed that all the colonies were positive for (14)C utilisation. Then one of the acetate-utilising bacteria was isolated. The isolate was characterised by phylogenetic analysis, cell morphology, Gram staining and growth at 30 °C. Phylogenetic analysis based on 16S rRNA sequencing showed that the isolate belonged to the genus Burkholderia. The bacterium was gram-negative rods and grew at 30 °C under aerobic conditions. Based on these characteristics, the isolate was identified as Burkholderia gladioli. Because B. gladioli is often found in soil, water and the rhizosphere, attention must be paid to the relationships between bacteria and the behaviour of (14)C to for the safety assessment of geological disposal of transuranic waste.

New Medium for Isolation of Bacteria From Cement Kiln Dust with a Potential to Apply in Bio-Concrete

NASA Astrophysics Data System (ADS)

Alshalif, A. F.; Irwan, J. M.; Othman, N.; Al-Gheethi, A.

2018-04-01

The present study aimed to introduce a new isolation medium named kiln dust medium (KDM) for recovering of bacteria from cement kiln dust with high pH (>pH 11) without the need for nutrients additives. The cement kiln dust samples were collected from five different areas of Cement Industries of Malaysia Berhad (CIMA). The bacterial isolates were recovered on KDM by direct plating technique. The chemical components for all collected samples were identified using X-ray fluorescence (XRF). The primary identification for the bacterial isolates indicated that these bacteria belongs to Bacillus spp. Based on the morphological characteristics. The growth curve of the bacterial strains was monitored using the optical density (OD) with 650 nm wavelength, which in role confirmed that all isolated bacteria had the ability to grow successfully in the proposed medium. The ability of the bacterial strains to grow at high pH reflects their potential in the bio-concrete applications (aerated and non-aerated concrete). These findings indicated that the cement kiln dust samples from Cement Industries represent the most appropriate source for bacteria used in the bioconcrete.

Culturable diversity of halophilic bacteria in foreshore soils

PubMed Central

Irshad, Aarzoo; Ahmad, Irshad; Kim, Seung Bum

2014-01-01

Halophilic bacteria are commonly found in natural environments containing significant concentration of NaCl such as inland salt lakes and evaporated sea-shore pools, as well as environments such as curing brines, salted food products and saline soils. Dependence on salt is an important phenotypic characteristic of halophilic bacteria, which can be used in the polyphasic characterization of newly discovered microorganisms. In this study the diversity of halophilic bacteria in foreshore soils of Daecheon, Chungnam, and Saemangeum, Jeonbuk, was investigated. Two types of media, namely NA and R2A supplemented with 3%, 5%, 9%, 15%, 20% and 30% NaCl were used. More than 200 halophilic bacteria were isolated and BOX-PCR fingerprinting analysis was done for the typing of the isolates. The BLAST identification results showed that isolated strains were composed of 4 phyla, Firmicutes (60%), Proteobacteria (31%), Bacteriodetes (5%) and Actinobacteria (4%). Isolates were affiliated with 16 genera and 36 species. Bacillus was the dominant genus in the phylum Firmicutes, comprising 24% of the total isolates. Halomonas (12%) and Shewanella (12%) were also found as the main genera. These findings show that the foreshore soil of Daecheon Beach and Saemangeum Sea of Korea represents an untapped source of bacterial biodiversity. PMID:25242943

Culturable diversity of halophilic bacteria in foreshore soils.

PubMed

Irshad, Aarzoo; Ahmad, Irshad; Kim, Seung Bum

2014-01-01

Halophilic bacteria are commonly found in natural environments containing significant concentration of NaCl such as inland salt lakes and evaporated sea-shore pools, as well as environments such as curing brines, salted food products and saline soils. Dependence on salt is an important phenotypic characteristic of halophilic bacteria, which can be used in the polyphasic characterization of newly discovered microorganisms. In this study the diversity of halophilic bacteria in foreshore soils of Daecheon, Chungnam, and Saemangeum, Jeonbuk, was investigated. Two types of media, namely NA and R2A supplemented with 3%, 5%, 9%, 15%, 20% and 30% NaCl were used. More than 200 halophilic bacteria were isolated and BOX-PCR fingerprinting analysis was done for the typing of the isolates. The BLAST identification results showed that isolated strains were composed of 4 phyla, Firmicutes (60%), Proteobacteria (31%), Bacteriodetes (5%) and Actinobacteria (4%). Isolates were affiliated with 16 genera and 36 species. Bacillus was the dominant genus in the phylum Firmicutes, comprising 24% of the total isolates. Halomonas (12%) and Shewanella (12%) were also found as the main genera. These findings show that the foreshore soil of Daecheon Beach and Saemangeum Sea of Korea represents an untapped source of bacterial biodiversity.

Extensive Horizontal Gene Transfer during Staphylococcus aureus Co-colonization In Vivo

PubMed Central

McCarthy, Alex J.; Loeffler, Anette; Witney, Adam A.; Gould, Katherine A.; Lloyd, David H.; Lindsay, Jodi A.

2014-01-01

Staphylococcus aureus is a commensal and major pathogen of humans and animals. Comparative genomics of S. aureus populations suggests that colonization of different host species is associated with carriage of mobile genetic elements (MGE), particularly bacteriophages and plasmids capable of encoding virulence, resistance, and immune evasion pathways. Antimicrobial-resistant S. aureus of livestock are a potential zoonotic threat to human health if they adapt to colonize humans efficiently. We utilized the technique of experimental evolution and co-colonized gnotobiotic piglets with both human- and pig-associated variants of the lineage clonal complex 398, and investigated growth and genetic changes over 16 days using whole genome sequencing. The human isolate survived co-colonization on piglets more efficiently than in vitro. During co-colonization, transfer of MGE from the pig to the human isolate was detected within 4 h. Extensive and repeated transfer of two bacteriophages and three plasmids resulted in colonization with isolates carrying a wide variety of mobilomes. Whole genome sequencing of progeny bacteria revealed no acquisition of core genome polymorphisms, highlighting the importance of MGE. Staphylococcus aureus bacteriophage recombination and integration into novel sites was detected experimentally for the first time. During colonization, clones coexisted and diversified rather than a single variant dominating. Unexpectedly, each piglet carried unique populations of bacterial variants, suggesting limited transmission of bacteria between piglets once colonized. Our data show that horizontal gene transfer occurs at very high frequency in vivo and significantly higher than that detectable in vitro. PMID:25260585

Heterotrophic and Autotrophic Microbial Populations in Cold Perennial Springs of the High Arctic ▿ †

PubMed Central

Perreault, Nancy N.; Greer, Charles W.; Andersen, Dale T.; Tille, Stefanie; Lacrampe-Couloume, Georges; Lollar, Barbara Sherwood; Whyte, Lyle G.

2008-01-01

The saline springs of Gypsum Hill in the Canadian high Arctic are a rare example of cold springs originating from deep groundwater and rising to the surface through thick permafrost. The heterotrophic bacteria and autotrophic sulfur-oxidizing bacteria (up to 40% of the total microbial community) isolated from the spring waters and sediments were classified into four phyla (Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria) based on 16S rRNA gene analysis; heterotrophic isolates were primarily psychrotolerant, salt-tolerant, facultative anaerobes. Some of the isolates contained genes for thiosulfate oxidation (soxB) and anoxygenic photosynthesis (pufM), possibly enabling the strains to better compete in these sulfur-rich environments subject to long periods of illumination in the Arctic summer. Although leucine uptake by the spring water microbial community was low, CO2 uptake was relatively high under dark incubation, reinforcing the idea that primary production by chemoautotrophs is an important process in the springs. The small amounts of hydrocarbons in gases exsolving from the springs (0.38 to 0.51% CH4) were compositionally and isotopically consistent with microbial methanogenesis and possible methanotrophy. Anaerobic heterotrophic sulfur oxidation and aerobic autotrophic sulfur oxidation activities were demonstrated in sediment slurries. Overall, our results describe an active microbial community capable of sustainability in an extreme environment that experiences prolonged periods of continuous light or darkness, low temperatures, and moderate salinity, where life seems to rely on chemolithoautotrophy. PMID:18805995

Identification of poly(cis-1,4-Isoprene) degradation intermediates during growth of moderately thermophilic actinomycetes on rubber and cloning of a functional lcp homologue from Nocardia farcinica strain E1.

PubMed

Ibrahim, Ebaid M A; Arenskötter, Matthias; Luftmann, Heinrich; Steinbüchel, Alexander

2006-05-01

The enrichment and isolation of thermophilic bacteria capable of rubber [poly(cis-1,4-isoprene)] degradation revealed eight different strains exhibiting both currently known strategies used by rubber-degrading mesophilic bacteria. Taxonomic characterization of these isolates by 16S rRNA gene sequence analysis demonstrated closest relationships to Actinomadura nitritigenes, Nocardia farcinica, and Thermomonospora curvata. While strains related to N. farcinica exhibited adhesive growth as described for mycolic acid-containing actinomycetes belonging to the genus Gordonia, strains related to A. nitritigenes and T. curvata formed translucent halos on natural rubber latex agar as described for several mycelium-forming actinomycetes. For all strains, optimum growth rates were observed at 50 degrees C. The capability of rubber degradation was confirmed by mineralization experiments and by gel permeation chromatography (GPC). Intermediates resulting from early degradation steps were purified by preparative GPC, and their analysis by infrared spectroscopy revealed the occurrence of carbonyl carbon atoms. Staining with Schiff's reagent also revealed the presence of aldehyde groups in the intermediates. Bifunctional isoprenoid species terminated with a keto and aldehyde function were found by matrix-assisted laser desorption ionization-time-of-flight and electrospray ionization mass spectrometry analyses. Evidence was obtained that biodegradation of poly(cis-1,4-isoprene) is initiated by endocleavage, rather than by exocleavage. A gene (lcp) coding for a protein with high homology to Lcp (latex-clearing protein) from Streptomyces sp. strain K30 was identified in Nocardia farcinica E1. Streptomyces lividans TK23 expressing this Lcp homologue was able to cleave synthetic poly(cis-1,4-isoprene), confirming its involvement in initial polymer cleavage.

Identification of Poly(cis-1,4-Isoprene) Degradation Intermediates during Growth of Moderately Thermophilic Actinomycetes on Rubber and Cloning of a Functional lcp Homologue from Nocardia farcinica Strain E1

PubMed Central

Ibrahim, Ebaid M. A.; Arenskötter, Matthias; Luftmann, Heinrich; Steinbüchel, Alexander

2006-01-01

The enrichment and isolation of thermophilic bacteria capable of rubber [poly(cis-1,4-isoprene)] degradation revealed eight different strains exhibiting both currently known strategies used by rubber-degrading mesophilic bacteria. Taxonomic characterization of these isolates by 16S rRNA gene sequence analysis demonstrated closest relationships to Actinomadura nitritigenes, Nocardia farcinica, and Thermomonospora curvata. While strains related to N. farcinica exhibited adhesive growth as described for mycolic acid-containing actinomycetes belonging to the genus Gordonia, strains related to A. nitritigenes and T. curvata formed translucent halos on natural rubber latex agar as described for several mycelium-forming actinomycetes. For all strains, optimum growth rates were observed at 50°C. The capability of rubber degradation was confirmed by mineralization experiments and by gel permeation chromatography (GPC). Intermediates resulting from early degradation steps were purified by preparative GPC, and their analysis by infrared spectroscopy revealed the occurrence of carbonyl carbon atoms. Staining with Schiff's reagent also revealed the presence of aldehyde groups in the intermediates. Bifunctional isoprenoid species terminated with a keto and aldehyde function were found by matrix-assisted laser desorption ionization-time-of-flight and electrospray ionization mass spectrometry analyses. Evidence was obtained that biodegradation of poly(cis-1,4-isoprene) is initiated by endocleavage, rather than by exocleavage. A gene (lcp) coding for a protein with high homology to Lcp (latex-clearing protein) from Streptomyces sp. strain K30 was identified in Nocardia farcinica E1. Streptomyces lividans TK23 expressing this Lcp homologue was able to cleave synthetic poly(cis-1,4-isoprene), confirming its involvement in initial polymer cleavage. PMID:16672480

Characterization of viable bacteria from Siberian permafrost by 16S rDNA sequencing

NASA Technical Reports Server (NTRS)

Shi, T.; Reeves, R. H.; Gilichinsky, D. A.; Friedmann, E. I.

1997-01-01

Viable bacteria were found in permafrost core samples from the Kolyma-Indigirka lowland of northeast Siberia. The samples were obtained at different depths; the deepest was about 3 million years old. The average temperature of the permafrost is -10 degrees C. Twenty-nine bacterial isolates were characterized by 16S rDNA sequencing and phylogenetic analysis, cell morphology, Gram staining, endospore formation, and growth at 30 degrees C. The majority of the bacterial isolates were rod shaped and grew well at 30 degrees C; but two of them did not grow at or above 28 degrees C, and had optimum growth temperatures around 20 degrees C. Thirty percent of the isolates could form endospores. Phylogenetic analysis revealed that the isolates fell into four categories: high-GC Gram-positive bacteria, beta-proteobacteria, gamma-proteobacteria, and low-GC Gram-positive bacteria. Most high-GC Gram-positive bacteria and beta-proteobacteria, and all gamma-proteobacteria, came from samples with an estimated age of 1.8-3.0 million years (Olyor suite). Most low-GC Gram-positive bacteria came from samples with an estimated age of 5,000-8,000 years (Alas suite).

Antibiotic-resistant bacteria in the Hudson River Estuary linked to wet weather sewage contamination.

PubMed

Young, Suzanne; Juhl, Andrew; O'Mullan, Gregory D

2013-06-01

Heterotrophic bacteria resistant to tetracycline and ampicillin were assessed in waterways of the New York City metropolitan area using culture-dependent approaches and 16S rRNA gene sequence analysis of resultant isolates. Resistant microbes were detected at all 10 sampling sites in monthly research cruises on the lower Hudson River Estuary (HRE), with highest concentrations detected at nearshore sites. Higher frequency sampling was conducted in Flushing Bay, to enumerate resistant microbes under both dry and wet weather conditions. Concentrations of ampicillin- and tetracycline-resistant bacteria, in paired samples, were positively correlated with one another and increased following precipitation. Counts of the fecal indicator, Enterococcus, were positively correlated with levels of resistant bacteria, suggesting a shared sewage-associated source. Analysis of 16S rRNA from isolates identified a phylogenetically diverse group of resistant bacteria, including genera containing opportunistic pathogens. The occurrence of Enterobacteriaceae, a family of enteric bacteria, was found to be significantly higher in resistant isolates compared to total heterotrophic bacteria and increased following precipitation. This study is the first to document the widespread distribution of antibiotic-resistant bacteria in the HRE and to demonstrate clearly a link between the abundance of antibiotic-resistant bacteria and levels of sewage-associated bacteria in an estuary.

Isolation and genotyping of free-living environmental isolates of Acanthamoeba spp. from bromeliads in Southern Brazil.

PubMed

Landell, Melissa Fontes; Salton, Juliana; Caumo, Karin; Broetto, Leonardo; Rott, Marilise B

2013-07-01

Species of Acanthamoeba are frequently isolated from distinct environmental sources such as water, soil, dust and air. They are responsible to cause infections and disease in humans and animals. In addition, Acanthamoeba sp. are considered an important reservoir of bacteria, virus and fungi, which act as "Trojan horses" to protect these microorganisms of harsh environmental conditions. In this study, nine Acanthamoeba isolates from bromeliads phylloplane were identified based on the morphology of cyst and trophozoite forms. The genotype level was accessed by the sequence analysis of Acanthamoeba small-subunit rRNA gene. Genotypic characterization grouped five isolates in the genotype T2/T6, three in the T4 genotype and one in the genotype T16. The results obtained indicate that the genotype T2/T6 is common on phylloplane. To predict the pathogenic potential of the Acanthamoeba isolates, thermo and osmotolerance assays were employed, although all isolates were capable of surviving at temperatures of 37°C, other tests will be conducted in the future to determine the potential pathogenic of the isolates. Altogether, our results revealed the importance of the presence of Acanthamoeba associated with bromeliads in Rio Grande do Sul, Brazil, and the necessity for further studies to determine the environmental distribution and the role of these species. Copyright © 2013 Elsevier Inc. All rights reserved.

Isolation of marine fungi Aspergillus sp. and its in vitro antifouling activity against marine bacteria.

PubMed

Thiyagarajan, Santhananmari; Bavya, Manoharan; Jamal, Alruwaili

2016-09-01

Biofouling is considered as a main issue of concern in aquatic environment causing severe economic loss and pollution. The aim of the present study was to isolate marine fungus antagonistic to biofouling bacteria and to define antifouling compounds present in it. Using standard plate method five predominant biofouling bacteria viz., Methylococcus sp., Flavobacterium sp., Marinococcus sp., Serratia sp. and Pseudomonas sp. were isolated from marine solid substances on Zobell's agar. Tolerance range of these bacteria to NaCl was 2-10%. Isolation of fungi from mangrove and estuarine sediments and their screening identified Aspergillus sp. EF4 as a potential isolate. This isolate caused inhibition of all the five test bacterial cultures measuring zone diameters respectively of 11, 16, 12, 13 and 11mm.? Subsequent to submerged fermentation using shaking flask method this fungus produced bioactive compounds within 5 days. The culture parameters optimized were raffinose as carbon source, yeast extract as lone nitrogen source, pH up to 9.0 and temperature up to 40?C. Antifouling compounds of culture filtrate were separated and detected by a three-step procedure involving thin layer chromatography, bioautography and preparative TLC. The in vitro assay involving glass slide-wooden stick-biofilm method revealed that these compounds could cause inhibition and destruction of bacteria to an extent of 2.16 x 104 CFU ml-1 and 2.46 x 104 CFU ml-1 respectively while growth of bacteria in control beaker was enumerated to be 4.41 x 104 CFU ml-1. High performance liquid chromatography of culture filtrate indicated probable principal antifouling compound as Fumonisin B2. Isolation of antagonistic marine fungus from Indian coast and detection of its antifouling compound would help in planning effective strategies for controlling biofouling in marine environment.

Identification by using MALDI-TOF mass spectrometry of lactic acid bacteria isolated from non-commercial yogurts in southern Anatolia, Turkey.

PubMed

Karaduman, Ayse; Ozaslan, Mehmet Ozaslan; Kilic, Ibrahim H; Bayil-Oguzkan, Sibel; Kurt, Bekir S; Erdogan, Nese

2017-03-01

Yogurt is a dairy product obtained by bacterial fermentation of milk. Commercial yogurts are produced using standard starters while, in the production of non-commercial yogurt, the microbiota is quite different since yogurts are used as starter for years. To determine the final characteristics of the fermented product it is necessary to know the biochemical properties of the starter cultures, such as acidity, aroma and flavor. This can only be achieved by identifying and characterizing the bacteria in starter cultures. In our study, 208 non-commercial yogurt samples were collected from 9 different locations in Anatolia, southern Turkey. Their pH and lactic acid bacteria profiles were analyzed. Isolated bacteria were identified by MALDI-TOF MS (matrix-assisted laser sesorption-ionization time-of-flight, mass spectrometry), which is a fast and reliable method for identification of bacterial isolates compared to classical laboratory methods. In this study, 41% of the isolates were identified by using this method, which is 99.9% and 34.0% confidence. The isolates contained two genera (Enterococcus and Lactobacillus) and four species. Afterwards, the four lactic acid bacteria were characterized physiologically and biochemically and we found that they differed from lactic acid bacteria used in commercial yogurt production. [Int Microbiol 20(1): 25-30 (2017)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

Detection of Extended Spectrum Beta-Lactamases Resistance Genes among Bacteria Isolated from Selected Drinking Water Distribution Channels in Southwestern Nigeria.

PubMed

Adesoji, Ayodele T; Ogunjobi, Adeniyi A

2016-01-01

Extended Spectrum Beta-Lactamases (ESBL) provide high level resistance to beta-lactam antibiotics among bacteria. In this study, previously described multidrug resistant bacteria from raw, treated, and municipal taps of DWDS from selected dams in southwestern Nigeria were assessed for the presence of ESBL resistance genes which include bla TEM, bla SHV, and bla CTX by PCR amplification. A total of 164 bacteria spread across treated (33), raw (66), and municipal taps (68), belonging to α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Flavobacteriia, Bacilli, and Actinobacteria group, were selected for this study. Among these bacteria, the most commonly observed resistance was for ampicillin and amoxicillin/clavulanic acid (61 isolates). Sixty-one isolates carried at least one of the targeted ESBL genes with bla TEM being the most abundant (50/61) and bla CTX being detected least (3/61). Klebsiella was the most frequently identified genus (18.03%) to harbour ESBL gene followed by Proteus (14.75%). Moreover, combinations of two ESBL genes, bla SHV + bla TEM or bla CTX + bla TEM, were observed in 11 and 1 isolate, respectively. In conclusion, classic bla TEM ESBL gene was present in multiple bacterial strains that were isolated from DWDS sources in Nigeria. These environments may serve as foci exchange of genetic traits in a diversity of Gram-negative bacteria.

Bacterial infection of the lower respiratory tract in 34 horses.

PubMed

Racklyeft, D J; Love, D N

2000-08-01

To investigate associations between the bacteriology and aspects of history, clinical presentation, outcome and pathology of lower respiratory tract disease of 34 horses. Detailed aerobic and anaerobic bacteriological investigations were performed on clinical specimens from horses with pneumonia, lung abscessation and necrotic pneumonia with or without pleurisy in an attempt to identify those bacteria that might contribute to the initiation and progression of infection. Bacteria were cultured from 33 of the 34 horses. In ten cases, only aerobic/facultatively anaerobic isolates were cultured while aerobic/facultatively anaerobic bacteria and obligately anaerobic bacteria were isolated in the other 23 cases. Moderate to large numbers of anaerobic bacteria were isolated only when the estimated duration of illness was at least five days. Bacteria were not cultured from 12 of the pleural fluid samples but were always cultured from pulmonary samples (either transtracheal aspirates from live horses or pulmonary lesions at necropsy). Streptococcus equi subsp zooepidemicus was isolated in the three cases where only one bacterial species was cultured. In the other 30 cases, multiple species were isolated. These included most often and in greatest numbers, Streptococcus equi subsp zooepidemicus, Pasteurellaceae, Escherichia coli, anaerobic cocci, Eubacterium fossor, Bacteroides tectum, Prevotella heparinolytica, Fusobacterium spp, and pigmented members of the genera Prevotella and Porphyromonas. Aerobic/facultatively anaerobic organisms were isolated from 97% of horses, while obligately anaerobic organisms were cultured from 68% of horses. There was no association between the isolation of any specific bacterium and the outcome of disease. However, obligately anaerobic bacteria (such as anaerobic cocci, Bacteroides tectum, P heparinolytica and Fusobacterium spp) and the facultatively anaerobic species Escherichia coli, were recovered more commonly from horses that died or were euthanased than from those that survived. There was an association between failure of horses to recover from pleuropneumonia and delay in diagnosis and initiation of treatment.

Isolation of Francisella tularensis and Yersinia pestis from Blood Cultures by Plasma Purification and Immunomagnetic Separation Accelerates Antibiotic Susceptibility Determination

PubMed Central

Aloni-Grinstein, Ronit; Schuster, Ofir; Yitzhaki, Shmuel; Aftalion, Moshe; Maoz, Sharon; Steinberger-Levy, Ida; Ber, Raphael

2017-01-01

The early symptoms of tularemia and plague, which are caused by Francisella tularensis and Yersinia pestis infection, respectively, are common to other illnesses, resulting in a low index of suspicion among clinicians. Moreover, because these diseases can be treated only with antibiotics, rapid isolation of the bacteria and antibiotic susceptibility testing (AST) are preferable. Blood cultures of patients may serve as a source for bacteria isolation. However, due to the slow growth rates of F. tularensis and Y. pestis on solid media, isolation by plating blood culture samples on proper agar plates may require several days. Thus, improving the isolation procedure prior to antibiotic susceptibility determination is a major clinically relevant need. In this study, we developed a rapid, selective procedure for the isolation of F. tularensis and Y. pestis from blood cultures. We examined drop-plating and plasma purification followed by immunomagnetic separation (IMS) as alternative isolation methods. We determined that replacing the classical isolation method with drop-plating is advantageous with respect to time at the expense of specificity. Hence, we also examined isolation by IMS. Sub-localization of F. tularensis within blood cultures of infected mice has revealed that the majority of the bacteria are located within the extracellular fraction, in the plasma. Y. pestis also resides within the plasma. Therefore, the plasma fraction was isolated from blood cultures and subjected to an IMS procedure using polyclonal anti-F. tularensis live vaccine strain (LVS) or anti-Y. pestis antibodies conjugated to 50-nm nano-beads. The time required to reach an inoculum of sufficient bacteria for AST was shortest when using the plasma and IMSs for both bacteria, saving up to 2 days of incubation for F. tularensis and 1 day for Y. pestis. Our isolation procedure provides a proof of concept for the clinical relevance of rapid isolation for AST from F. tularensis- and Y. pestis-infected patients. PMID:28293231

Antibacterial activity of amino- and amido- terminated poly (amidoamine)-G6 dendrimer on isolated bacteria from clinical specimens and standard strains.

PubMed

Rastegar, Ayoob; Nazari, Shahram; Allahabadi, Ahmad; Falanji, Farahnaz; Akbari Dourbash, Fakhreddin Akbari Dourbash; Rezai, Zahra; Alizadeh Matboo, Soudabeh; Hekmat-Shoar, Reza; Mohseni, Seyed Mohsen; Majidi, Gharib

2017-01-01

Background: Nanoscale poly (amidoamine) dendrimers have been investigated for their biological demands, but their antibacterial activity has not been widely discovered. Thus, the sixth generation of poly (amidoamine) dendrimer (PAMAM-G6) was synthesized and its antibacterial activities were evaluated on Gram-negative bacteria; P. aeruginosa, E. coli, A. baumannii, S. typhimurium, S. dysenteriae, K. pneumoniae, P. mirabilis , and Gram-positive bacteria, and S.aureus and B. subtilis , which were isolated from different clinical specimens and standard strains of these bacteria. Methods: In this study, 980 specimens including urine (47%), blood (27%), sputum (13%), wounds (8%), and burns (5%) were collected from clinical specimens of 16 hospitals and clinics in city of Sabzevar, Iran. Then, the target bacteria were isolated and identified using standard methods. Minimum inhibitory concentration and minimum bactericidal concentrations against Gram-positive and Gram-negative bacteria were determined according to guidelines described by clinical and laboratory standards institute (CLSI). Standard discs were prepared using 0.025, 0.25, 2.5, and 25 μg/mL concentrations of PAMAM-G6 on Mueller-Hinton agar plates to determinate the zone of inhibition. The cytotoxicity of PAMAM-G6 dendrimer was evaluated in HCT116 cells by MTT assay. Results: The most important isolated bacteria were E. coli (23.65%), S. aureus (24.7%), P. aeruginosa (10.49%), B. subtilis (7.7%), S. typhimurium (8.87%), A. baumannii (7.02%), K. pneumoniae (7.1%), P. mirabilis (6.46%), and S. dysenteriae (3.6%). Moreover, it was found that poly (amidoamine)-G6 exhibited more antibacterial efficacy on standard strains than isolated bacteria from clinical samples (p<0.05). The cytotoxicity of PAMAM-G6 to the cells showed that cytotoxicity depended on the concentration level and exposure time. Conclusion: The PAMAM-G6 dendrimer showed a positive impact on the removal of dominant bacterial isolated from clinical specimens and standard strains.

Antibacterial activity of amino- and amido- terminated poly (amidoamine)-G6 dendrimer on isolated bacteria from clinical specimens and standard strains

PubMed Central

Rastegar, Ayoob; Nazari, Shahram; Allahabadi, Ahmad; Falanji, Farahnaz; Akbari Dourbash, Fakhreddin Akbari Dourbash; Rezai, Zahra; Alizadeh Matboo, Soudabeh; Hekmat-Shoar, Reza; Mohseni, Seyed Mohsen; Majidi, Gharib

2017-01-01

Background: Nanoscale poly (amidoamine) dendrimers have been investigated for their biological demands, but their antibacterial activity has not been widely discovered. Thus, the sixth generation of poly (amidoamine) dendrimer (PAMAM-G6) was synthesized and its antibacterial activities were evaluated on Gram-negative bacteria; P. aeruginosa, E. coli, A. baumannii, S. typhimurium, S. dysenteriae, K. pneumoniae, P. mirabilis, and Gram-positive bacteria, and S.aureus and B. subtilis, which were isolated from different clinical specimens and standard strains of these bacteria. Methods: In this study, 980 specimens including urine (47%), blood (27%), sputum (13%), wounds (8%), and burns (5%) were collected from clinical specimens of 16 hospitals and clinics in city of Sabzevar, Iran. Then, the target bacteria were isolated and identified using standard methods. Minimum inhibitory concentration and minimum bactericidal concentrations against Gram-positive and Gram-negative bacteria were determined according to guidelines described by clinical and laboratory standards institute (CLSI). Standard discs were prepared using 0.025, 0.25, 2.5, and 25 μg/mL concentrations of PAMAM-G6 on Mueller-Hinton agar plates to determinate the zone of inhibition. The cytotoxicity of PAMAM-G6 dendrimer was evaluated in HCT116 cells by MTT assay. Results: The most important isolated bacteria were E. coli (23.65%), S. aureus (24.7%), P. aeruginosa (10.49%), B. subtilis (7.7%), S. typhimurium (8.87%), A. baumannii (7.02%), K. pneumoniae (7.1%), P. mirabilis (6.46%), and S. dysenteriae (3.6%). Moreover, it was found that poly (amidoamine)–G6 exhibited more antibacterial efficacy on standard strains than isolated bacteria from clinical samples (p<0.05). The cytotoxicity of PAMAM-G6 to the cells showed that cytotoxicity depended on the concentration level and exposure time. Conclusion: The PAMAM-G6 dendrimer showed a positive impact on the removal of dominant bacterial isolated from clinical specimens and standard strains. PMID:29445693

Quantitative analyses of the bacterial microbiota of rearing environment, tilapia and common carp cultured in earthen ponds and inhibitory activity of its lactic acid bacteria on fish spoilage and pathogenic bacteria.

PubMed

Kaktcham, Pierre Marie; Temgoua, Jules-Bocamdé; Ngoufack Zambou, François; Diaz-Ruiz, Gloria; Wacher, Carmen; Pérez-Chabela, María de Lourdes

2017-02-01

The present study aimed to evaluate the bacterial load of water, Nile Tilapia and common Carp intestines from earthen ponds, isolate lactic acid bacteria (LAB) and assess their antimicrobial activity against fish spoilage and pathogenic bacteria. Following enumeration and isolation of microorganisms the antimicrobial activity of the LAB isolates was evaluated. Taxonomic identification of selected antagonistic LAB strains was assessed, followed by partial characterisation of their antimicrobial metabolites. Results showed that high counts (>4 log c.f.u ml -1 or 8 log c.f.u g -1 ) of total aerobic bacteria were recorded in pond waters and fish intestines. The microbiota were also found to be dominated by Salmonella spp., Vibrio spp., Staphylococcus spp. and Escherichia coli. LAB isolates (5.60%) exhibited potent direct and extracellular antimicrobial activity against the host-derived and non host-derived spoilage and pathogenic bacteria. These antagonistic isolates were identified and Lactococcus lactis subsp. lactis was found as the predominant (42.85%) specie. The strains displayed the ability to produce lactic, acetic, butyric, propionic and valeric acids. Bacteriocin-like inhibitory substances with activity against Gram-positive and Gram-negative (Vibrio spp. and Pseudomonas aeruginosa) bacteria were produced by three L. lactis subsp. lactis strains. In this study, the LAB from the microbiota of fish and pond water showed potent antimicrobial activity against fish spoilage or pathogenic bacteria from the same host or ecological niche. The studied Cameroonian aquatic niche is an ideal source of antagonistic LAB that could be appropriate as new fish biopreservatives or disease control agents in aquaculture under tropical conditions in particular or worldwide in general.

Newly cultured bacteria with broad diversity isolated from 8 week continuous culture enrichments of cow feces on complex polysaccharides

USDA-ARS?s Scientific Manuscript database

One of the fascinating functions of the mammalian intestinal microbiota is the fermentation of plant cell wall components. Eight week continuous culture enrichments of cow feces with cellulose and xylan/pectin were used to isolate bacteria from this community. A total of 459 bacterial isolates were ...

Association of metal tolerance with multiple antibiotic resistance of bacteria isolated from drinking water.

PubMed Central

Calomiris, J J; Armstrong, J L; Seidler, R J

1984-01-01

Bacterial isolates from the drinking water system of an Oregon coastal community were examined to assess the association of metal tolerance with multiple antibiotic resistance. Positive correlations between tolerance to high levels of Cu2+, Pb2+, and Zn2+ and multiple antibiotic resistance were noted among bacteria from distribution waters but not among bacteria from raw waters. Tolerances to higher levels of Al3+ and Sn2+ were demonstrated more often by raw water isolates which were not typically multiple antibiotic resistant. A similar incidence of tolerance to Cd2+ was demonstrated by isolates of both water types and was not associated with multiple antibiotic resistance. These results suggest that simultaneous selection phenomena occurred in distribution water for bacteria which exhibited unique patterns of tolerance to Cu2+, Pb2+, and Zn2+ and antibiotic resistance. PMID:6742841

Faecal carriage of extended-spectrum β-lactamase-producing and AmpC β-lactamase-producing bacteria among Danish army recruits.

PubMed

Hammerum, A M; Lester, C H; Jakobsen, L; Porsbo, L J

2011-04-01

During May and June 2008, 84 Danish army recruits were tested for faecal carriage of extended-spectrum β-lactamase (ESBL)-producing and AmpC β-lactamase-producing bacteria. Three ESBL-producing (CTX-M-14a) Escherichia coli isolates, two AmpC-producing (CMY-2) E. coli isolates and one AmpC-producing (CMY-34) Citrobacter freundii isolate were detected. Two of the CTX-M-14a E. coli isolates had similar pulsed-field gel electrophoresis and multilocus sequence typing profiles, indicating the same origin or transmission between the two army recruits. The bla(CTX-M-14a) genes were transferable to an E. coli recipient. These commensal bacteria therefore constitute a reservoir of resistance genes that can be transferred to other pathogenic bacteria in the intestine. © 2010 The Authors. Clinical Microbiology and Infection © 2010 European Society of Clinical Microbiology and Infectious Diseases.

[Diversity of Bacillus species inhabiting on the surface and endophyte of lichens collected from Wuyi Mountain].

PubMed

Ge, Cibin; Liu, Bo; Che, Jianmei; Chen, Meichun; Liu, Guohong; Wei, Jiangchun

2015-05-04

The present work reported the isolation, identification and diversity of Bacillus species colonizing on the surface and endophyte in lichens collected from Wuyi Mountain. Nine lichen samples of Evernia, Stereocaulon, Menegazzia and other 6 genera belonging to 7 families were collected from Wuyi mountain nature reserve. The bacillus-like species colonizing on the surface and endophyte in these lichens were isolated and identified by 16S rRNA gene sequence analysis. There was no bacillus-like species isolated from Evernia, Ramalina and Lecarona. A total of 34 bacillus-like bacteria were isolated from another 6 lichen samples. These bacteria were identified as 24 species and were classified into Bacillus, Paenibacillus, Brevibacillus, Lysinibacillus and Viridiibacillus. Paenibacillus and Bacillus are the dominant genera, and accounting for 41. 2% and 35. 3% of all isolated bacteria respectively. Brevibacillus, Lysinibacillus and Viridiibacillu were first reported being isolated from lichens. There were different species and quantity of bacillus colonizing on the surface and endophyte in different lichens. The quantity of bacillus colonizing on the surface of Physcia was more than 3.85 x 10(6) cfu/g and was the largest in the isolated bacteria, while the species of bacillus colonizing on the surface and endophyte in Stereocaulon was the most abundant. Most of the isolated bacteria were colonizing on (in) one lichen genera, but Paenibacillus taichungensis, Paenibacillus odorifer, Brevibacillus agri, Lysinibacillus xylanilyticus was respectively colonizing on (in) 2-3 lichen genera and Bacillus mycoides was colonizing on (in) Menegazzia, Cladonia Physcia, and Stereocaulon. There are species and quantity diversity of bacillus colonizing on (in) lichens.

Bacterial and fungal endophthalmitis in upper Egypt: related species and risk factors.

PubMed

Gharamah, A A; Moharram, A M; Ismail, M A; Al-Hussaini, A K

2012-08-01

To study risk factors, contributing factors of bacterial and fungal endophthalmitis in Upper Egypt, test the isolated species sensitive to some therapeutic agents, and to investigate the air-borne bacteria and fungi in opthalmology operating rooms. Thirty one cases of endophthalmitis were clinically diagnosed and microbiologically studied. Indoor air-borne bacteria and fungi inside four air-conditioned operating rooms in the Ophthalmology Department at Assiut University Hospitals were also investigated. The isolated microbes from endophthalmitis cases were tested for their ability to produce some extracellular enzymes including protease, lipase, urease, phosphatase and catalase. Also the ability of 5 fungal isolates from endophthalmitis origin to produce mycotoxins and their sensitivity to some therapeutic agents were studied. Results showed that bacteria and fungi were responsihle for infection in 10 and 6 cases of endophthalmitis, respectively and only 2 cases produced a mixture of bacteria and fungi. Trauma was the most prevalent risk factor of endophthalmitis where 58.1% of the 31 cases were due to trauma. In ophthalmology operating rooms, different bacterial and fungal species were isolated. 8 bacterial and 5 fungal isolates showed their ability to produce enzymes while only 3 fungal isolates were able to produce mycotoxins. Terbinafine showed the highest effect against most isolates in vitro. The ability of bacterial and fungal isolates to produce extracellular enzymes and mycotoxins may be aid in the invasion and destruction of eye tissues. Microbial contamination of operating rooms with air-borne bacteria and fungi in the present work may be a source of postoperative endophthalmitis.

Diazotrophic bacteria isolated from wild rice Oryza glumaepatula (Poaceae) in the Brazilian Amazon.

PubMed

Júnior, Paulo Ivan Fernandes; Pereira, Gilmara Maria Duarte; Perin, Liamara; da Silva, Luana Mesquita; Baraúna, Alexandre Cardoso; Alvess, Francilene Muniz; Passos, Samuel Ribeiro; Zilli, Jerri Edson

2013-06-01

The association of wild grasses with diazotrophic bacteria in Brazilian biomes is poorly understood. The isolation and characterization of bacteria associated with wild grasses can contribute to understand the diazotrophic ecology as well as to identify bacteria with biotechnological applications. In this study, we isolated and characterized diazotrophic bacterial isolates from Oryza glumaepatula collected in Cerrado and Forest areas of the Amazon in Roraima State, Brazil. Healthy O. glumepatula plants were collected at five sampling sites at Forest and seven at Cerrado, respectively. The plants were collected at the Cerrado areas in September 2008 while the Forest plants were collected in June/2008 and April/2009. The plants and the soil adhering to the roots were transferred to pots and grown for 35 days in greenhouse conditions. During the harvest, the shoots and the roots were crushed separately in a saline solution; the suspension was diluted serially and inoculated in Petri dishes containing Dyg's medium. All distinct bacterial colonies were purified in the same medium. The diazotrophic capacity of each bacterium in microaerophilic conditions was assessed in semisolid BMGM medium. In addition, the pellicles forming bacterial isolates were also evaluated by PCR amplification for nifH gene. The diversity of nifH bacteria was analyzed by Box-PCR fingerprinting. For selected strains, the growth promoting capacity of O. sativa as a model plant was also evaluated. A total of 992 bacterial isolates were obtained. Fifty-one bacteria were able to form pellicles in the semisolid medium and 38 also positively amplified the 360 bp nifH gene fragment. Among the 38 nifH+ isolates, 24 were obtained from the shoots, while 14 originated from the roots. The Box-PCR profiles showed that the bacterial isolates obtained in this study presented a low similarity with the reference strains belonging to the Herbaspirillum, Azospirillum and Burkholderia genus. The growth-promoting ability was confirmed for at least five isolates. For these bacteria, the root and shoot growing results showed higher increases when compared to those observed in plants inoculated with the evaluated reference strains. These results indicate that O. glumaepatula is colonized by a high diverse diazotrophic community in the Brazilian Amazon. Further investigations are now being carried out to determine the taxonomic positions of these isolates and their growth promoting mechanisms.

Bacteriocins of Non-aureus Staphylococci Isolated from Bovine Milk.

PubMed

Carson, Domonique A; Barkema, Herman W; Naushad, Sohail; De Buck, Jeroen

2017-09-01

Non- aureus staphylococci (NAS), the bacteria most commonly isolated from the bovine udder, potentially protect the udder against infection by major mastitis pathogens due to bacteriocin production. In this study, we determined the inhibitory capability of 441 bovine NAS isolates (comprising 26 species) against bovine Staphylococcus aureus Furthermore, inhibiting isolates were tested against a human methicillin-resistant S. aureus (MRSA) isolate using a cross-streaking method. We determined the presence of bacteriocin clusters in NAS whole genomes using genome mining tools, BLAST, and comparison of genomes of closely related inhibiting and noninhibiting isolates and determined the genetic organization of any identified bacteriocin biosynthetic gene clusters. Forty isolates from 9 species ( S. capitis , S. chromogenes , S. epidermidis , S. pasteuri , S. saprophyticus , S. sciuri , S. simulans , S. warneri , and S. xylosus ) inhibited growth of S. aureus in vitro , 23 isolates of which, from S. capitis , S. chromogenes , S. epidermidis , S. pasteuri , S. simulans , and S. xylosus , also inhibited MRSA. One hundred five putative bacteriocin gene clusters encompassing 6 different classes (lanthipeptides, sactipeptides, lasso peptides, class IIa, class IIc, and class IId) in 95 whole genomes from 16 species were identified. A total of 25 novel bacteriocin precursors were described. In conclusion, NAS from bovine mammary glands are a source of potential bacteriocins, with >21% being possible producers, representing potential for future characterization and prospective clinical applications. IMPORTANCE Mastitis (particularly infections caused by Staphylococcus aureus ) costs Canadian dairy producers $400 million/year and is the leading cause of antibiotic use on dairy farms. With increasing antibiotic resistance and regulations regarding use, there is impetus to explore bacteriocins (bacterially produced antimicrobial peptides) for treatment and prevention of bacterial infections. We examined the ability of 441 NAS bacteria from Canadian bovine milk samples to inhibit growth of S. aureus in the laboratory. Overall, 9% inhibited growth of S. aureus and 58% of those also inhibited MRSA. In NAS whole-genome sequences, we identified >21% of NAS as having bacteriocin genes. Our study represents a foundation to further explore NAS bacteriocins for clinical use. Copyright © 2017 American Society for Microbiology.

Bacteriocins of Non-aureus Staphylococci Isolated from Bovine Milk

PubMed Central

Carson, Domonique A.; Barkema, Herman W.; Naushad, Sohail

2017-01-01

ABSTRACT Non-aureus staphylococci (NAS), the bacteria most commonly isolated from the bovine udder, potentially protect the udder against infection by major mastitis pathogens due to bacteriocin production. In this study, we determined the inhibitory capability of 441 bovine NAS isolates (comprising 26 species) against bovine Staphylococcus aureus. Furthermore, inhibiting isolates were tested against a human methicillin-resistant S. aureus (MRSA) isolate using a cross-streaking method. We determined the presence of bacteriocin clusters in NAS whole genomes using genome mining tools, BLAST, and comparison of genomes of closely related inhibiting and noninhibiting isolates and determined the genetic organization of any identified bacteriocin biosynthetic gene clusters. Forty isolates from 9 species (S. capitis, S. chromogenes, S. epidermidis, S. pasteuri, S. saprophyticus, S. sciuri, S. simulans, S. warneri, and S. xylosus) inhibited growth of S. aureus in vitro, 23 isolates of which, from S. capitis, S. chromogenes, S. epidermidis, S. pasteuri, S. simulans, and S. xylosus, also inhibited MRSA. One hundred five putative bacteriocin gene clusters encompassing 6 different classes (lanthipeptides, sactipeptides, lasso peptides, class IIa, class IIc, and class IId) in 95 whole genomes from 16 species were identified. A total of 25 novel bacteriocin precursors were described. In conclusion, NAS from bovine mammary glands are a source of potential bacteriocins, with >21% being possible producers, representing potential for future characterization and prospective clinical applications. IMPORTANCE Mastitis (particularly infections caused by Staphylococcus aureus) costs Canadian dairy producers $400 million/year and is the leading cause of antibiotic use on dairy farms. With increasing antibiotic resistance and regulations regarding use, there is impetus to explore bacteriocins (bacterially produced antimicrobial peptides) for treatment and prevention of bacterial infections. We examined the ability of 441 NAS bacteria from Canadian bovine milk samples to inhibit growth of S. aureus in the laboratory. Overall, 9% inhibited growth of S. aureus and 58% of those also inhibited MRSA. In NAS whole-genome sequences, we identified >21% of NAS as having bacteriocin genes. Our study represents a foundation to further explore NAS bacteriocins for clinical use. PMID:28667105

Determination of Active Phagocytosis of Unopsonized Porphyromonas gingivalis by Macrophages and Neutrophils Using the pH-Sensitive Fluorescent Dye pHrodo

PubMed Central

Lenzo, Jason C.; O'Brien-Simpson, Neil M.; Cecil, Jessica; Holden, James A.

2016-01-01

Phagocytosis of pathogens is an important component of the innate immune system that is responsible for the removal and degradation of bacteria as well as their presentation via the major histocompatibility complexes to the adaptive immune system. The periodontal pathogen Porphyromonas gingivalis exhibits strain heterogeneity, which may affect a phagocyte's ability to recognize and phagocytose the bacterium. In addition, P. gingivalis is reported to avoid phagocytosis by antibody and complement degradation and by invading phagocytic cells. Previous studies examining phagocytosis have been confounded by both the techniques employed and the potential of the bacteria to invade the cells. In this study, we used a novel, pH-sensitive dye, pHrodo, to label live P. gingivalis strains and examine unopsonized phagocytosis by murine macrophages and neutrophils and human monocytic cells. All host cells examined were able to recognize and phagocytose unopsonized P. gingivalis strains. Macrophages had a preference to phagocytose P. gingivalis strain ATCC 33277 over other strains and clinical isolates in the study, whereas neutrophils favored P. gingivalis W50, ATCC 33277, and one clinical isolate over the other strains. This study revealed that all P. gingivalis strains were capable of being phagocytosed without prior opsonization with antibody or complement. PMID:27021243

Comparative genomics provides evidence for the 3-hydroxypropionate autotrophic pathway in filamentous anoxygenic phototrophic bacteria and in hot spring microbial mats.

PubMed

Klatt, Christian G; Bryant, Donald A; Ward, David M

2007-08-01

Stable carbon isotope signatures of diagnostic lipid biomarkers have suggested that Roseiflexus spp., the dominant filamentous anoxygenic phototrophic bacteria inhabiting microbial mats of alkaline siliceous hot springs, may be capable of fixing bicarbonate via the 3-hydroxypropionate pathway, which has been characterized in their distant relative, Chloroflexus aurantiacus. The genomes of three filamentous anoxygenic phototrophic Chloroflexi isolates (Roseiflexus sp. RS-1, Roseiflexus castenholzii and Chloroflexus aggregans), but not that of a non-photosynthetic Chloroflexi isolate (Herpetosiphon aurantiacus), were found to contain open reading frames that show a high degree of sequence similarity to genes encoding enzymes in the C. aurantiacus pathway. Metagenomic DNA sequences from the microbial mats of alkaline siliceous hot springs also contain homologues of these genes that are highly similar to genes in both Roseiflexus spp. and Chloroflexus spp. Thus, Roseiflexus spp. appear to have the genetic capacity for carbon dioxide reduction via the 3-hydroxypropionate pathway. This may contribute to heavier carbon isotopic signatures of the cell components of native Roseiflexus populations in mats compared with the signatures of cyanobacterial cell components, as a similar isotopic signature would be expected if Roseiflexus spp. were participating in photoheterotrophic uptake of cyanobacterial photosynthate produced by the reductive pentose phosphate cycle.

Isolation of Optically Targeted Single Bacteria by Application of Fluidic Force Microscopy to Aerobic Anoxygenic Phototrophs from the Phyllosphere

PubMed Central

Stiefel, Philipp; Zambelli, Tomaso

2013-01-01

In their natural environment, bacteria often behave differently than they do under laboratory conditions. To gain insight into the physiology of bacteria in situ, dedicated approaches are required to monitor their adaptations and specific behaviors under environmental conditions. Optical microscopy is crucial for the observation of fundamental characteristics of bacteria, such as cell shape, size, and marker gene expression. Here, fluidic force microscopy (FluidFM) was exploited to isolate optically selected bacteria for subsequent identification and characterization. In this study, bacteriochlorophyll-producing bacteria, which can be visualized due to their characteristic fluorescence in the infrared range, were isolated from leaf washes. Bacterial communities from the phyllosphere were investigated because they harbor genes indicative of aerobic anoxygenic photosynthesis. Our data show that different species of Methylobacterium express their photosystem in planta, and they show a distinct pattern of bacteriochlorophyll production under laboratory conditions that is dependent on supplied carbon sources. PMID:23770907

Isolation of Potential Bacteria as Inoculum for Biofloc Formation in Pacific Whiteleg Shrimp, Litopenaeus vannamei Culture Ponds.

PubMed

Kasan, Nor Azman; Ghazali, Nurarina Ayuni; Ikhwanuddin, Mhd; Ibrahim, Zaharah

2017-01-01

A new green technology to reduce environmental damages while optimizing production of Pacific Whiteleg shrimp, Litopenaeus vannamei was developed known as "Biofloc technology". Microbial communities in biofloc aggregates are responsible in eliminating water exchange and producing microbial proteins that can be used as supplemented feed for L. vannamei. This study aimed to isolate and identify potential bioflocculant-producing bacteria to be used as inoculum for rapid formation of biofloc. For the purpose of this study, bacterial communities during 0, 30 and 70 days of culture (DOC) of L. vannamei grow-out ponds were isolated and identified through phenotypic and 16S rDNA sequences analysis. Phylogenetic relationships between isolated bacteria were then evaluated through phylogenetic tree analysis. One-way analysis of variance (ANOVA) was used to compare the differences of microbial communities at each DOC. Out of 125 bacterial isolates, nine species of bacteria from biofloc were identified successfully. Those bacteria species were identified as Halomonas venusta, H. aquamarina, Vibrio parahaemolyticus, Bacillus infantis, B. cereus, B. safensis, Providencia vermicola, Nitratireductor aquimarinus and Pseudoalteromonas sp., respectively. Through phylogenetic analysis, these isolates belong to Proteobacteria and Firmicutes families under the genera of Halomonas sp., Vibrio sp., Bacillus sp., Providencia sp., Nitratireductor sp. and Pseudoalteromonas sp. In this study, bioflocculant-producing bacteria were successfully identified which are perfect candidates in forming biofloc to reduce water pollution towards a sustainable aquaculture industry. Presence of Halomonas sp. and Bacillus sp. in all stages of biofloc formation reinforces the need for new development regarding the ability of these species to be used as inoculum in forming biofloc rapidly.

Distribution and Persistence of Staphylococcus and Micrococcus Species and Other Aerobic Bacteria on Human Skin1

PubMed Central

Kloos, Wesley E.; Musselwhite, Margaret S.

1975-01-01

The distribution of Staphylococcus and Micrococcus species and associated coryneform bacteria, Acinetobacter, Klebsiella, Enterobacter, Bacillus, and Streptomyces on skin was determined during October 1971 from samples collected on persons living in North Carolina and New Jersey. Persistence of these organisms on skin was estimated in temporal studies conducted during the period from June 1971 to June 1972 on persons living in North Carolina. Staphylococci and coryneforms were the most predominant and persistent bacteria isolated from the nares and axillae. Staphylococci, coryneforms, micrococci, and Bacillus were the most predominant and persistent bacteria isolated from the head, legs, and arms. Acinetobacters were most frequently isolated during the warmer months of the years. Staphylococcus aureus and S. epidermidis were the most predominant and persistent staphylococci isolated from the nares, whereas S. epidermidis and S. hominis were the most predominant and persistent staphylococci isolated from the axillae, head, legs, and arms. S. capitis was often isolated from the head and arms and S. haemolyticus was often isolated from the head, legs, and arms. S. simulans, S. xylosus, S. cohnii, S. saprophyticus, S. warneri, and an unclassified coagulase-positive species were only occasionally isolated from skin. Micrococcus luteus was the most predominant and persistent Micrococcus isolated from skin and preferred regions of the head, legs, and arms. M. varians was the second most frequent Micrococcus isolated. M. lylae, M. sedentarius, M. roseus, M. kristinae, and M. nishinomiyaensis were only occasionally isolated from skin. M. lylae was most frequently isolated during the colder months of the years. PMID:810086

Antibacterial Activities of Endophytic Bacteria Isolated from Taxus brevifolia Against Foodborne Pathogenic Bacteria.

PubMed

Islam, Nurul; Choi, Jaehyuk; Baek, Kwang-Hyun

2018-05-01

Endophytes are a potential source of novel bioactive compounds with medicinal properties. In this study, 41 endophytic bacteria (EB) were isolated from tissues of a medicinally important plant Taxus brevifolia (Pacific yew). The objective was to screen all the EB isolates for their antibacterial effects against five foodborne pathogenic bacteria: Bacillus cereus ATCC10876, Staphylococcus aureus ATCC12600, Listeria monocytogenes ATCC19115, Escherichia coli ATCC43890, and Salmonella Typhimurium ATCC19585. Among the EB isolates, T. brevifolia seed (TbS)-8, T. brevifolia fleshy part of fruit (TbFl)-10, T. brevifolia leaf (TbL)-22, TbS-29, and TbL-34 exerted significant antibacterial activity against the tested foodborne pathogens. Especially TbFl-10 showed the highest antibacterial activity against all the tested bacteria and was identified as Paenibacillus kribbensis (Pk). Furthermore, an ethyl acetate extract of Pk-TbFl-10 possessed antibacterial activities against the tested five foodborne pathogenic bacteria, with zones of inhibition from 15.71 ± 2.85 to 13.01 ± 2.12 mm. Scanning electron microscopy analysis revealed ruptured, lysed, shrunk, and swollen cells of all the tested foodborne pathogens treated with the ethyl acetate extract of Pk-TbFl-10, suggesting that a metabolite(s) of Pk-TbFl-10 penetrates the cell membrane and causes cell lysis leading to cell death. Our results indicate that Pk-TbFl-10 isolated from T. brevifolia can serve as a novel source of natural antibacterial agents against foodborne pathogenic bacteria, with potential applications in the pharmaceutical industry.