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1

N-demethylation of neonicotinoid insecticide acetamiprid by bacterium Stenotrophomonas maltophilia CGMCC 1.1788  

Microsoft Academic Search

Our previous study found that Stenotrophomonas maltophilia CGMCC 1.1788 could hydroxylate imidacloprid (IMI) to 5-hydroxy IMI. Here we first report that S. maltophilia CGMCC 1.1788 can demethylate acetamiprid (AAP) to form IM 2-1 that was characterized by HPLC-MS\\/MS and NMR. IM 2-1 retained\\u000a only 10.5% contact activity and 13.1% oral activity of AAP against horsebean aphid. Time course of biotransformation

Ting Chen; Yi-Jun Dai; Juan-Fang Ding; Sheng Yuan; Jue-Ping Ni

2008-01-01

2

Hydroxylation of thiacloprid by bacterium Stenotrophomonas maltophilia CGMCC1.1788  

Microsoft Academic Search

Chloropyridinyl neonicotinoid insecticides play a major role in crop protection and flea control on cats and dogs. Imidacloprid,\\u000a thiacloprid and acetamiprid have in common the 6-chloro-3-pyridinylmethyl group but differ in the nitroguanidine or cyanoamidine\\u000a substituent on an acyclic or cyclic moiety. Our previous study found that Stenotrophomonas maltophilia CGMCC 1.1788 could hydroxylate imidacloprid to 5-hydroxy imidacloprid, and 5-hydroxy imidacloprid was

Yin-Juan Zhao; Yi-Jun Dai; Ci-Gang Yu; Jun Luo; Wen-Ping Xu; Jue-Ping Ni; Sheng Yuan

2009-01-01

3

Stenotrophomonas maltophilia: an Emerging Global Opportunistic Pathogen  

PubMed Central

Summary: Stenotrophomonas maltophilia is an emerging multidrug-resistant global opportunistic pathogen. The increasing incidence of nosocomial and community-acquired S. maltophilia infections is of particular concern for immunocompromised individuals, as this bacterial pathogen is associated with a significant fatality/case ratio. S. maltophilia is an environmental bacterium found in aqueous habitats, including plant rhizospheres, animals, foods, and water sources. Infections of S. maltophilia can occur in a range of organs and tissues; the organism is commonly found in respiratory tract infections. This review summarizes the current literature and presents S. maltophilia as an organism with various molecular mechanisms used for colonization and infection. S. maltophilia can be recovered from polymicrobial infections, most notably from the respiratory tract of cystic fibrosis patients, as a cocolonizer with Pseudomonas aeruginosa. Recent evidence of cell-cell communication between these pathogens has implications for the development of novel pharmacological therapies. Animal models of S. maltophilia infection have provided useful information about the type of host immune response induced by this opportunistic pathogen. Current and emerging treatments for patients infected with S. maltophilia are discussed. PMID:22232370

2012-01-01

4

Heavy Metal Tolerance in Stenotrophomonas maltophilia  

PubMed Central

Stenotrophomonas maltophilia is an aerobic, non-fermentative Gram-negative bacterium widespread in the environment. S. maltophilia Sm777 exhibits innate resistance to multiple antimicrobial agents. Furthermore, this bacterium tolerates high levels (0.1 to 50 mM) of various toxic metals, such as Cd, Pb, Co, Zn, Hg, Ag, selenite, tellurite and uranyl. S. maltophilia Sm777 was able to grow in the presence of 50 mM selenite and 25 mM tellurite and to reduce them to elemental selenium (Se0) and tellurium (Te0) respectively. Transmission electron microscopy and energy dispersive X-ray analysis showed cytoplasmic nanometer-sized electron-dense Se0 granules and Te0 crystals. Moreover, this bacterium can withstand up to 2 mM CdCl2 and accumulate this metal up to 4% of its biomass. The analysis of soluble thiols in response to ten different metals showed eightfold increase of the intracellular pool of cysteine only in response to cadmium. Measurements by Cd K-edge EXAFS spectroscopy indicated the formation of Cd-S clusters in strain Sm777. Cysteine is likely to be involved in Cd tolerance and in CdS-clusters formation. Our data suggest that besides high tolerance to antibiotics by efflux mechanisms, S. maltophilia Sm777 has developed at least two different mechanisms to overcome metal toxicity, reduction of oxyanions to non-toxic elemental ions and detoxification of Cd into CdS. PMID:18253487

Pages, Delphine; Rose, Jerome; Conrod, Sandrine; Cuine, Stephane; Carrier, Patrick; Heulin, Thierry; Achouak, Wafa

2008-01-01

5

Structure of Aminodeoxychorismate Synthase from Stenotrophomonas maltophilia  

PubMed Central

PabB, aminodeoxychorismate synthase, is the chorismic acid binding component of the heterodimeric PabAB complex that converts chorismic acid to 4-amino-4-deoxychorismate, a precursor of p-aminobenzoate and folic acid in microorganisms. The second component, a glutamine amidotransferase subunit, PabA, generates ammonia that is channeled to the PabB active site where it attacks the C4 carbon of a chorismate derived intermediate that is covalently bound, through C2, to an active site lysine residue. The presence of a PIKGT motif was, until recently, believed to be discriminate PabB enzymes from the closely related enzyme anthranilate synthase, which typically contains a PIAGT active site motif and does not form a covalent enzyme-substrate intermediate with chorismate. A subclass of PabB enzymes that employ an alternative mechanism requiring two equivalents of ammonia from glutamine and that feature a noncovalently bound 2-amino-2-deoxyisochorismate intermediate was recently identified. Here we report the 2.25 Å crystal structure of PabB from the emerging pathogen Stenotrophomonas maltophilia. It is the first reported structure of a PabB that features the PIAGT motif. Surprisingly, no dedicated pabA is evident in the genome of S. maltophilia suggesting that another cellular amidotransferase is able to fulfill the role of PabA in this organism. Evaluation of the ammonia-dependent aminodeoxychorismate synthase activity of S. maltophilia PabB alone revealed that it is virtually inactive. However, in the presence of a heterologous PabA surrogate, typical levels of activity were observed using either glutamine or ammonia as the nitrogen source. Additionally, the structure suggests that a key segment of the polypeptide can remodel itself to interact with a nonspecialized or shared amidotransferase partner in vivo. The structure and mass spectral analysis further suggest that S. maltophilia PabB, like Escherichia coli PabB, binds tryptophan in a vestigial regulatory site. The observation that the binding site is unoccupied in the crystal structure, however, suggests the affinity may be low relative to E. coli PabB. PMID:23230967

Bera, Asim K.; Atanasova, Vesna; Dhanda, Anjali; Ladner, Jane E.; Parsons, James F.

2012-01-01

6

Unilateral conjunctival ulcer due to Stenotrophomonas maltophilia infection  

PubMed Central

We report a case of unilateral conjunctival ulcer due to Stenotrophomonas maltophilia infection in an immunocompetent individual. A 44-year-old male presented with complaints of pain and yellowish discharge in the right eye for one week. Patient underwent complete ophthalmic evaluation and relevant laboratory investigations. Anterior segment examination revealed localized conjunctival and episcleral congestion with conjunctival ulceration on the bulbar conjunctiva in the right eye. Gram's stain revealed gram-negative bacilli. Culture and sensitivity revealed S. maltophilia and responded well to topical moxifloxacin with systemic co-trimoxazole therapy. PMID:22446910

Mahendradas, Padmamalini; Avadhani, Kavitha; Anandula, Venkatramana; Shetty, Rohit

2012-01-01

7

Effect of iron and sodium chloride on biofilm development of stenotrophomonas maltophilia.  

E-print Network

??Stenotrophomonas maltophilia is an emerging worldwide, opportunistic respiratory pathogen that is associated with a significant case-fatality ratio in immunocompromised patient populations and has the ability… (more)

Martinez, Rudy F

2011-01-01

8

Stenotrophomonas maltophilia pneumonia in cancer patients without traditional risk factors for infection, 1997–2004  

Microsoft Academic Search

In order to elucidate the spectrum of Stenotrophomonas maltophilia pneumonia in cancer patients without traditional risk factors, 44 cancer patients (cases) with S. maltophilia pneumonia in whom S. maltophilia pneumonia risk factors were not present were compared with two S. maltophilia pneumonia risk groups (controls) including 43 neutropenic non-intensive care unit (ICU) and 21 non-neutropenic ICU patients.\\u000a The case and

G. Aisenberg; K. V. Rolston; B. F. Dickey; D. P. Kontoyiannis; I. I. Raad; A. Safdar

2007-01-01

9

Biofilm Formation by Stenotrophomonas maltophilia: Modulation by Quinolones, Trimethoprim-Sulfamethoxazole, and Ceftazidime  

Microsoft Academic Search

We investigated the in vitro effects of seven fluoroquinolones (ciprofloxacin, grepafloxacin, levofloxacin, moxifloxacin, norfloxacin, ofloxacin, and rufloxacin), compared to those of trimethoprim-sulfamethoxazole (SXT) and ceftazidime on total biomass and cell viability of Stenotrophomonas maltophilia biofilm. S. maltophilia attached rapidly to polystyrene, withi n2ho fincubation, and then biofilm formation increased over time, reaching maximum growth at 24 h. In the presence

Giovanni Di Bonaventura; Ilaria Spedicato; Domenico D'Antonio; Iole Robuffo; Raffaele Piccolomini

2004-01-01

10

Draft Genome Sequence of Stenotrophomonas maltophilia Strain M30, Isolated from a Chronic Pressure Ulcer in an Elderly Patient  

PubMed Central

Stenotrophomonas maltophilia is an emerging opportunistic pathogen with an increasing prevalence of multidrug-resistant strains. Here, we report the draft genome sequence of S. maltophilia strain M30, isolated from a pressure ulcer in an elderly patient. PMID:24926059

Huedo, Pol; Conchillo-Sole, Oscar; Yero, Daniel; Martinez-Servat, Sonia

2014-01-01

11

Complete Genome Sequence of Stenotrophomonas maltophilia Type Strain 810-2 (ATCC 13637)  

PubMed Central

An emerging nosocomial pathogen, Stenotrophomonas maltophila has a high mortality rate in those it infects. Here, we present the complete genome sequence of Stenotrophomonas maltophilia 810-2 (ATCC 13637), the type strain of the species. The 5-Mb (66.1% G+C content) genome has been deposited in NCBI under accession number CP008838. PMID:25258273

Davenport, K. W.; Daligault, H. E.; Minogue, T. D.; Broomall, S. M.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Gibbons, H. S.; Jaissle, J.; Li, P.-E.; Rosenzweig, C. N.; Scholz, M. B.

2014-01-01

12

Complete Genome Sequence of Stenotrophomonas maltophilia Type Strain 810-2 (ATCC 13637).  

PubMed

An emerging nosocomial pathogen, Stenotrophomonas maltophila has a high mortality rate in those it infects. Here, we present the complete genome sequence of Stenotrophomonas maltophilia 810-2 (ATCC 13637), the type strain of the species. The 5-Mb (66.1% G+C content) genome has been deposited in NCBI under accession number CP008838. PMID:25258273

Davenport, K W; Daligault, H E; Minogue, T D; Broomall, S M; Bruce, D C; Chain, P S; Coyne, S R; Gibbons, H S; Jaissle, J; Li, P-E; Rosenzweig, C N; Scholz, M B; Johnson, S L

2014-01-01

13

l-Glucitol Catabolism in Stenotrophomonas maltophilia Ac  

PubMed Central

The carbohydrate catabolism of the bacterium Stenotrophomonas maltophilia Ac (previously named Pseudomonas sp. strain Ac), which is known to convert the unnatural polyol l-glucitol to d-sorbose during growth on the former as the sole source of carbon and energy, was studied in detail. All enzymes operating in a pathway that channels l-glucitol via d-sorbose into compounds of the intermediary metabolism were demonstrated, and for some prominent reactions the products of conversion were identified. d-Sorbose was converted by C-3 epimerization to d-tagatose, which, in turn, was isomerized to d-galactose. d-Galactose was the initial substrate of the De Ley-Doudoroff pathway, involving reactions of NAD-dependent oxidation of d-galactose to d-galactonate, its dehydration to 2-keto-3-deoxy-d-galactonate, and its phosphorylation to 2-keto-3-deoxy-d-galactonate 6-phosphate. Finally, aldol cleavage yielded pyruvate and d-glycerate 3-phosphate as the central metabolic intermediates. PMID:11823194

Brechtel, Elke; Huwig, Alexander; Giffhorn, Friedrich

2002-01-01

14

Chitinase A from Stenotrophomonas maltophilia shows transglycosylation and antifungal activities.  

PubMed

Stenotrophomonas maltophilia chitinase (StmChiA and StmChiB) genes were cloned and expressed as soluble proteins of 70.5 and 41.6 kDa in Escherichia coli. Ni-NTA affinity purified StmChiA and StmChiB were optimally active at pH 5.0 and 7.0, respectively and exhibited broad range pH activity. StmChiA and StmChiB had an optimum temperature of 40°C and are stable up to 50 and 40°C, respectively. Hydrolytic activity on chitooligosaccharides indicated that StmChiA was an endo-acting enzyme releasing chitobiose and StmChiB was both exo/endo-acting enzyme with the release of GlcNAc as the final product. StmChiA showed higher preference to ?-chitin and exhibited transglycosylation on even chain length tetra- and hexameric substrates. StmChiA, and not StmChiB, was active on chitinous polymers and showed antifungal activity against Fusarium oxysporum. PMID:23428818

Suma, Katta; Podile, Appa Rao

2013-04-01

15

Rapid identification of Stenotrophomonas maltophilia by peptide nucleic acid fluorescence in situ hybridization  

PubMed Central

The objective of this study was to develop a novel peptide nucleic acid (PNA) probe for Stenotrophomonas maltophilia identification by fluorescence in situ hybridization (FISH). The probe was evaluated using 33 human and veterinary clinical S. maltophilia isolates and 45 reference strains representing common bacterial species in the respiratory tract. The probe displayed 100% sensitivity and 100% specificity on pure cultures and allowed detection in sputum from cystic fibrosis patients. The detection limit was 104 CFU/mL in spiked tracheal aspirate and bronchoalveolar lavage from healthy horses. Altogether the study shows that this species-specific PNA FISH probe facilitates rapid detection of S. maltophilia in biological specimens. PMID:25356348

Hansen, N; Rasmussen, A K I; Fiandaca, M J; Kragh, K N; Bjarnsholt, T; H?iby, N; Stender, H; Guardabassi, L

2014-01-01

16

Differential Biofilm Formation and Motility Associated with Lipopolysaccharide\\/Exopolysaccharide-Coupled Biosynthetic Genes in Stenotrophomonas maltophilia  

Microsoft Academic Search

Microorganisms can develop biofilms or clogging mats, caus- ing the failure of septic tanks, systems for on-site wastewater disposal. If water in these clogged systems were contaminated by pathogens, it would pose a threat to human health. We isolated Stenotrophomonas maltophilia strain WR-C from a clogged septic tank system that consistently formed biofilms on sand grains, produced exopolysaccharides (EPS), and

Tzu-Pi Huang; Eileen B. Somers; Amy C. Lee Wong

2006-01-01

17

Functional Characterization of the RNA Chaperone Hfq in the Opportunistic Human Pathogen Stenotrophomonas maltophilia  

PubMed Central

Hfq is an RNA-binding protein known to regulate a variety of cellular processes by interacting with small RNAs (sRNAs) and mRNAs in prokaryotes. Stenotrophomonas maltophilia is an important opportunistic pathogen affecting primarily hospitalized and immunocompromised hosts. We constructed an hfq deletion mutant (?hfq) of S. maltophilia and compared the behaviors of wild-type and ?hfq S. maltophilia cells in a variety of assays. This revealed that S. maltophilia Hfq plays a role in biofilm formation and cell motility, as well as susceptibility to antimicrobial agents. Moreover, Hfq is crucial for adhesion to bronchial epithelial cells and is required for the replication of S. maltophilia in macrophages. Differential RNA sequencing analysis (dRNA-seq) of RNA isolated from S. maltophilia wild-type and ?hfq strains showed that Hfq regulates the expression of genes encoding flagellar and fimbrial components, transmembrane proteins, and enzymes involved in different metabolic pathways. Moreover, we analyzed the expression of several sRNAs identified by dRNA-seq in wild-type and ?hfq S. maltophilia cells grown in different conditions on Northern blots. The accumulation of two sRNAs was strongly reduced in the absence of Hfq. Furthermore, based on our dRNA-seq analysis we provide a genome-wide map of transcriptional start sites in S. maltophilia. PMID:22923593

Roscetto, Emanuela; Angrisano, Tiziana; Costa, Valerio; Casalino, Mariassunta; Förstner, Konrad U.; Sharma, Cynthia M.; Di Nocera, Pier Paolo

2012-01-01

18

Susceptibility of Stenotrophomonas maltophilia clinical strains in China to antimicrobial combinations.  

PubMed

We aimed to investigate the activity levels of several combinations of antimicrobials against Stenotrophomonas maltophilia. In this study, the antimicrobial susceptibility of S. maltophilia clinical isolates was determined, and the synergistic activity of three pairs of antimicrobial combinations was evaluated by the fractional inhibitory concentration index (FICI). The antimicrobial susceptibility in vitro against 83 S. maltophilia strains was greater for minocycline (80·7%) than for trimethoprim-sulfamethoxazole (51·8%), and levofloxacin (50·6%). The rate of resistance was highest for ticarcillin-clavulanate and ceftazidime (63·8%) and resistance to trimethoprim-sulfamethoxazole (TMP-SMX) was 48·2%. All three combinations were tested against susceptible isolates. Two of the combinations, TMP-SMX+ceftazidime and levofloxacin+ceftazidime were more effective than the combination of TMP-SMX+levofloxacin. We recommend acquiring more clinical data in order to explore combination therapy, which is a promising treatment of S. maltophilia infections. PMID:24588423

Hu, Li-Fen; Gao, Li-Ping; Ye, Ying; Chen, Xi; Zhou, Xiang-Tian; Yang, Hai-Fei; Liiu, Yan-Yan; Mei, Qing; Li, Jia-Bin

2014-10-01

19

Genomic sequence of temperate phage Smp131 of Stenotrophomonas maltophilia that has similar prophages in xanthomonads  

PubMed Central

Background Stenotrophomonas maltophilia is a ubiquitous Gram-negative bacterium previously named as Xanthomonas maltophilia. This organism is an important nosocomial pathogen associated with infections in immunocompromised patients. Clinical isolates of S. maltophilia are mostly resistant to multiple antibiotics and treatment of its infections is becoming problematic. Several virulent bacteriophages, but not temperate phage, of S. maltophilia have been characterized. Results In this study, a temperate myophage of S. maltophilia (Smp131) was isolated and characterized. Sequence analysis showed that its genome is 33,525-bp long with 47 open reading frames (ORFs). Its similarity to P2-like phages and prophages in S. maltophilia and several Xanthomonas pathovars includes genomic organization, arrangement of several operons, and possession of a slippery sequence T7G for translational frameshifting in tail assembly genes. Smp131 encodes a tyrosine family integrase that shares low degrees of similarity with those of other phages and a lysin belonging to family 19 chitinase that is observed in plants and some bacteria, although not in phages. tRNA are the preferred sites for host integration of Smp131 and the related phages: tRNA-Thr for Smp131 and prophage of S. maltophilia K279a; tRNA-Lys for prophages of X. campestris pv. campestris ATCC33913, X. oryzae pv. oryzae strains MAFF311018, and KACC10331; and tRNA-Asn for prophage of X. oryzae pv. oryzae PXO99A and remnant of X. axonopodis pv. citri 306. Regions flanking the prophages are varied highly in nucleotide sequence and rich in transposase genes, suggesting that frequent insertion/excision had occurred. Conclusions Prevalence of closely related prophages in Stenotrophomonas and Xanthomonads may have contributed to the diversity of these closely related species owing to possible horizontal gene transfer mediated by the phages. PMID:24472137

2014-01-01

20

Extracellular serine proteases from Stenotrophomonas maltophilia: Screening, isolation and heterologous expression in E. coli  

Microsoft Academic Search

A large strain collection comprising antagonistic bacteria was screened for novel detergent proteases. Several strains displayed protease activity on agar plates containing skim milk but were inactive in liquid media. Encapsulation of cells in alginate beads induced protease production. Stenotrophomonas maltophilia emerged as best performer under washing conditions. For identification of wash-active proteases, four extracellular serine proteases called StmPr1, StmPr2,

D. Ribitsch; S. Heumann; W. Karl; J. Gerlach; R. Leber; R. Birner-Gruenberger; K. Gruber; I. Eiteljoerg; P. Remler; P. Siegert; J. Lange; K. H. Maurer; G. Berg; G. M. Guebitz; H. Schwab

21

A New Stenotrophomonas maltophilia Strain Producing Laccase. Use in Decolorization of Synthetics Dyes  

Microsoft Academic Search

Laccase activity was detected in a soil bacterium Stenotrophomonas maltophilia AAP56 identified by biochemical and molecular methods. It was produced in cells at the stationary growth phase in Luria Bertani\\u000a (LB) medium added by 0.4 mM copper sulfate. The addition of CuSO4 in culture medium improved production of laccase activity. However, one laccase enzyme was detected by native polyacrylamide\\u000a gel electrophoresis.

Said Galai; Ferid Limam; M. Nejib Marzouki

2009-01-01

22

Complete Genome Sequence of IME13, a Stenotrophomonas maltophilia bacteriophage with large burst size and unique plaque polymorphism.  

PubMed

Stenotrophomonas maltophilia bacteriophage IME13 is a virulent phage with a large burst size, exceeding 3,000, much larger than that of any other stenotrophomonas phage reported before. It showed effective lysis of Stenotrophomonas maltophilia. Additionally, the phage IME13 developed at least three obviously different sizes of plaques when a single plaque was picked out and inoculated on a double-layer Luria broth agar plate with its host. Here we announce its complete genome and describe major findings from its annotation. PMID:22997416

Fan, Huahao; Huang, Yong; Mi, Zhiqiang; Yin, Xiuyun; Wang, Lin; Fan, Hang; Zhang, Zhiyi; An, Xiaoping; Chen, Jiankui; Tong, Yigang

2012-10-01

23

Stenotrophomonas maltophilia in Mexico: antimicrobial resistance, biofilm formation and clonal diversity.  

PubMed

Stenotrophomonas maltophilia is an important multidrug-resistant nosocomial pathogen associated with high mortality. Our aim was to examine antimicrobial susceptibility, biofilm production and clonal relatedness of clinical isolates of S. maltophilia. S. maltophilia isolates were collected between 2006 and 2013 from two tertiary care hospitals in Mexico. Antimicrobial susceptibility was evaluated by the broth microdilution method. PCR was used to determine the presence of ?-lactamase genes L1 and L2. Biofilm formation was assessed with crystal violet staining. Clonal relatedness was determined by PFGE. Among the 119 collected S. maltophilia isolates, 73 (61.3?%) were from the respiratory tract. Resistance levels exceeded 75?% for imipenem, meropenem, ampicillin, aztreonam, gentamicin and tobramycin. Resistance to trimethoprim-sulfamethoxazole was 32.8?%. L1 and L2 genes were detected in 77.1?% (91/118) and 66.9?% (79/118) of isolates, respectively. All S. maltophilia strains were able to produce biofilms. Strains were classified as weak (47.9?%, 57/119), moderate (38.7?%, 46/119), or strong (13.4?%, 16/119) biofilm producers. A total of 89 distinct PFGE types were identified and 21.6?% (22/102) of the isolates were distributed in nine clusters. This is the first study in Mexico to reveal characteristics of clinical isolates of S. maltophilia. Clonal diversity data indicate low cross-transmission of S. maltophilia in a hospital setting. The high antibiotic resistance underscores the need for continuous surveillance of S. maltophilia in hospital settings in Mexico. PMID:25165124

Flores-Treviño, Samantha; Gutiérrez-Ferman, Jessica Lizzeth; Morfín-Otero, Rayo; Rodríguez-Noriega, Eduardo; Estrada-Rivadeneyra, Diego; Rivas-Morales, Catalina; Llaca-Díaz, Jorge M; Camacho-Ortíz, Adrián; Mendoza-Olazarán, Soraya; Garza-González, Elvira

2014-11-01

24

Stenotrophomonas maltophilia strains from cystic fibrosis patients: genomic variability and molecular characterization of some virulence determinants.  

PubMed

The genetic relatedness of 52 Stenotrophomonas maltophilia strains, collected from various environmental and clinical sources, including cystic fibrosis (CF) patients, as well as the presence and the expression of some virulence-associated genes were studied. Pulsed-field gel electrophoresis (PFGE) analysis identified 47 profiles and three clusters of isolates with an identical PFGE pattern considered to be indistinguishable strains. Restriction fragment length polymorphism of the gyrB gene grouped the 52 strains into nine different profiles. Most CF clinical isolates (29 out of 41) showed profile 1, while the analysis of the hypervariable regions of the 16S rRNA gene revealed five distinct allelic variations, with the majority of CF isolates (23 out of 41) belonging to sequence group 1. Furthermore, the strains were characterized for motility and expression of virulence-associated genes, including genes encoding type-1 fimbriae, proteases (StmPr1 and StmPr2) and esterase. All S. maltophilia strains exhibited a very broad range of swimming and twitching motility, while none showed swarming motility. A complete smf-1 gene was PCR-amplified only from clinically derived S. maltophilia strains. Finally, the virulence of representative S. maltophilia strains impaired in the expression of proteases and esterase activities was evaluated by infecting larvae of the wax moth Galleria mellonella. The results obtained strongly indicate that the major extracellular protease StmPr1 may be a relevant virulence factor of S. maltophilia. PMID:20952251

Nicoletti, Mauro; Iacobino, Angelo; Prosseda, Gianni; Fiscarelli, Ersilia; Zarrilli, Raffaele; De Carolis, Elena; Petrucca, Andrea; Nencioni, Lucia; Colonna, Bianca; Casalino, Mariassunta

2011-01-01

25

Identification of swine influenza A virus and Stenotrophomonas maltophilia co-infection in Chinese pigs  

PubMed Central

Background Influenza virus virulence can be exacerbated by bacterial co-infections. Swine influenza virus (SIV) infection together with some bacteria is found to enhance pathogenicity. Methods SIV-positive samples suspected of containing bacteria were used for bacterial isolation and identification. Antimicrobial susceptibility testing was performed by disc diffusion methods. To investigate the interaction of SIV and the bacteria in vitro, guinea pigs were used as mammalian hosts to determine the effect on viral susceptibility and transmissibility. Differences in viral titers between groups were compared using Student’s t-test. Results During surveillance for SIV in China from 2006 to 2009, seven isolates (24.14%) of 29 influenza A viruses were co-isolated with Stenotrophomonas maltophilia from nasal and tracheal swab samples of pigs. Antimicrobial susceptibility testing showed that the bacteria possessed a high level of resistance towards clinically used antibiotics. To investigate the interaction between these two microorganisms in influencing viral susceptibility and transmission in humans, guinea pigs were used as an infection model. Animals were inoculated with SIV or S. maltophilia alone or co-infected with SIV and S. maltophilia. The results showed that although no transmission among guinea pigs was observed, virus–bacteria co-infections resulted in higher virus titers in nasal washes and trachea and a longer virus shedding period. Conclusions This is the first report of influenza virus co-infection with S. maltophilia in the Chinese swine population. Increased replication of virus by co-infection with multidrug resistant bacteria might increase the infection rate of SIV in humans. The control of S. maltophilia in clinics will contribute to reducing the spread of SIV in pigs and humans. PMID:22913775

2012-01-01

26

Genotyping of Environmental and Clinical Stenotrophomonas maltophilia Isolates and their Pathogenic Potential  

PubMed Central

Stenotrophomonas maltophilia is a highly versatile species with useful biotechnological potential but also with pathogenic properties. In light of possible differences in virulence characteristics, knowledge about genomic subgroups is therefore desirable. Two different genotyping methods, rep-PCR fingerprinting and partial gyrB gene sequencing were used to elucidate S. maltophilia intraspecies diversity. Rep-PCR fingerprinting revealed the presence of 12 large subgroups, while gyrB gene sequencing distinguished 10 subgroups. For 8 of them, the same strain composition was shown with both typing methods. A subset of 59 isolates representative for the gyrB groups was further investigated with regards to their pathogenic properties in a virulence model using Dictyostelium discoideum and Acanthamoeba castellanii as host organisms. A clear tendency towards accumulation of virulent strains could be observed for one group with A. castellanii and for two groups with D. discoideum. Several virulent strains did not cluster in any of the genetic groups, while other groups displayed no virulence properties at all. The amoeba pathogenicity model proved suitable in showing differences in S. maltophilia virulence. However, the model is still not sufficient to completely elucidate virulence as critical for a human host, since several strains involved in human infections did not show any virulence against amoeba. PMID:22110692

Adamek, Martina; Overhage, Jorg; Bathe, Stephan; Winter, Josef; Fischer, Reinhard; Schwartz, Thomas

2011-01-01

27

A Highly Thermostable Xylanase from Stenotrophomonas maltophilia: Purification and Partial Characterization  

PubMed Central

Seven xylanolytic bacterial strains were isolated from saw-dust dump soil. The bacterial strain X6 was selected on the basis of the highest xylanase activity with no cellulase contamination. It was identified as Stenotrophomonas maltophilia by biochemical tests and 16S rRNA gene sequencing approach. Xylanase production studies by S. maltophilia on different commercial xylans and agro-industrial residues suggested that wheat bran was the best carbon source for xylanase production (26.4 ± 0.6?IU/mL). The studies with inorganic and organic nitrogen sources suggested yeast extract as the best support for xylanase production (25 ± 0.6?IU/mL). Maximum xylanase production was observed at initial medium pH = 8.0 (23.8 ± 0.4?IU/mL) with production at pH = 7.0 and pH = 9.0 being almost comparable. Xylanase produced by S. maltophilia was purified to homogeneity using ammonium sulfate precipitation, gel filtration, and ion exchange chromatography. The final purification was 5.43-fold with recovery of 19.18%. The molecular weight of the purified xylanase protein was ~142?kDa. Both crude and purified xylanase had good stability at pH = 9.0 and 80°C with activity retention greater than 90% after 30?min incubation. The enzyme stability at high temperature and alkaline pH make it potentially effective for industrial applications. PMID:24416589

Kumar, Sharad; Singh, Sudheer Kumar

2013-01-01

28

Infections Caused by Stenotrophomonas maltophilia in Recipients of Hematopoietic Stem Cell Transplantation  

PubMed Central

Stenotrophomonas maltophilia (S. maltophilia) is a globally emerging Gram-negative bacillus that is widely spread in environment and hospital equipment. Recently, the incidence of infections caused by this organism has increased, particularly in patients with hematological malignancy and in recipients of hematopoietic stem cell transplantation (HSCT) having neutropenia, mucositis, diarrhea, central venous catheters or graft versus host disease and receiving intensive cytotoxic chemotherapy, immunosuppressive therapy, or broad-spectrum antibiotics. The spectrum of infections in HSCT recipients includes pneumonia, urinary tract and surgical site infection, peritonitis, bacteremia, septic shock, and infection of indwelling medical devices. The organism exhibits intrinsic resistance to many classes of antibiotics including carbapenems, aminoglycosides, most of the third-generation cephalosporins, and other ?-lactams. Despite the increasingly reported drug resistance, trimethoprim-sulfamethoxazole is still the drug of choice. However, the organism is still susceptible to ticarcillin-clavulanic acid, tigecycline, fluoroquinolones, polymyxin-B, and rifampicin. Genetic factors play a significant role not only in evolution of drug resistance but also in virulence of the organism. The outcome of patients having S. maltophilia infections can be improved by: using various combinations of novel therapeutic agents and aerosolized aminoglycosides or colistin, prompt administration of in vitro active antibiotics, removal of possible sources of infection such as infected indwelling intravascular catheters, and application of strict infection control measures. PMID:25202682

Al-Anazi, Khalid Ahmed; Al-Jasser, Asma M.

2014-01-01

29

Molecular characterization of virulence determinants of Stenotrophomonas maltophilia strains isolated from patients affected by cystic fibrosis.  

PubMed

Stenotrophomonas maltophilia is an emerging nosocomial bacterial pathogen which is currently isolated with increasing frequency from the airways of cystic fibrosis (CF) patients. In this study 13 S. maltophilia strains (11 isolated from the airways of independent CF patients, and two non-CF respiratory reference strains) have been characterized for the expression of several virulence-associated factors. In particular, the ability to form biofilm on abiotic surfaces has been determined and correlated with different features, such as motility, adherence and the ability to invade A549 respiratory epithelial cells. Moreover, the presence of a flagellum-associated gene as well as that of the StmPr1 gene, which encodes an extracellular protease, have been determined by Southern blot hybridization. Our data indicate that the different degree of biofilm formation exhibited by the 11 CF isolates does not correlate with motility, ability to adhere to and invade A549 cells, or with the presence of flagella. On the other hand, among the CF isolates the StmPr1 gene was found only in two strains, both able to establish chronic lung infections in CF patients. Moreover, only four of the strains analyzed show a temperature-independent antibiotic-resistance profile, suggesting either a different origin of these strains or an intervening adaptation to host tissues. PMID:17880766

Di Bonaventura, G; Prosseda, G; Del Chierico, F; Cannavacciuolo, S; Cipriani, P; Petrucca, A; Superti, F; Ammendolia, M G; Concato, C; Fiscarelli, E; Casalino, M; Piccolomini, R; Nicoletti, M; Colonna, B

2007-01-01

30

Effects of Green Tea Compound Epigallocatechin-3-Gallate against Stenotrophomonas maltophilia Infection and Biofilm  

PubMed Central

We investigated the in vitro and in vivo activities of epigallocatechin-3-gallate (EGCg), a green tea component, against Stenotrophomonas maltophilia (Sm) isolates from cystic fibrosis (CF) patients. In vitro effects of EGCg and the antibiotic colistin (COL) on growth inhibition, survival, and also against young and mature biofilms of S. maltophilia were determined. Qualitative and quantitative changes on the biofilms were assessed by confocal laser scanning microscopy (CLSM). Further, in vivo effects of nebulized EGCg in C57BL/6 and Cftr mutant mice during acute Sm lung infection were evaluated. Subinhibitory concentrations of EGCg significantly reduced not only biofilm formation, but also the quantity of viable cells in young and mature biofilms. CLSM showed that EGCg-exposed biofilms exhibited either a change in total biofilm biovolume or an increase of the fraction of dead cells contained within the biofilm in a dose depended manner. Sm infected wild-type and Cftr mutant mice treated with 1,024 mg/L EGCg by inhalation exhibited significantly lower bacterial counts than those undergoing no treatment or treated with COL. EGCg displayed promising inhibitory and anti-biofilm properties against CF Sm isolates in vitro and significantly reduced Sm bacterial counts in an acute infection model with wild type and CF mice. This natural compound may represent a novel therapeutic agent against Sm infection in CF. PMID:24690894

Vidigal, Pedrina G.; Musken, Mathias; Becker, Katrin A.; Haussler, Susanne; Wingender, Jost; Steinmann, Eike; Kehrmann, Jan; Gulbins, Erich; Buer, Jan; Rath, Peter Michael; Steinmann, Jorg

2014-01-01

31

SmeC, an Outer Membrane Multidrug Efflux Protein of Stenotrophomonas maltophilia  

PubMed Central

A homologue of the mexAB-oprM multidrug efflux operon of Pseudomonas aeruginosa, smeABC, was cloned from Stenotrophomonas maltophilia by using, as a probe, a PCR product amplified from this organism with primers based on the mexB sequence. The smeABC genes were hyperexpressed in a mutant strain displaying resistance to several antimicrobials, including aminoglycosides, ?-lactams, and fluoroquinolones. Deletions in smeC but not smeB compromised this resistance, suggesting that SmeC contributed to the multidrug resistance of the mutant as part of another, as-yet-unidentified multidrug efflux system. Consistent with SmeC functioning independently of SmeAB, a promoter activity was identified upstream of smeC. Upstream of the smeABC genes, a putative two-gene operon, smeSR, encoding homologues of bacterial two-component regulatory systems was identified. The cloned smeR gene activated expression of a smeA-lacZ fusion, indicating that SmeR positively regulates expression of the smeABC genes. Consistent with this, the multidrug resistance of the SmeABC-hyperexpressing mutant was compromised by deletion of smeR. Intriguingly, SmeC expression in S. maltophilia paralleled a ?-lactamase activity provided by a C-terminally truncated L2 enzyme, which was apparently responsible for the ?-lactam resistance of the SmeABC-hyperexpressing mutant. This represents the first report of coregulation of an efflux resistance determinant and a ?-lactamase. PMID:11796339

Li, Xian-Zhi; Zhang, Li; Poole, Keith

2002-01-01

32

Transformations of selenate and selenite by Stenotrophomonas maltophilia isolated from a seleniferous agricultural drainage pond sediment.  

PubMed

A Gram-negative bacterium, identified as Stenotrophomonas maltophilia by fatty acid analysis and 16S rRNA sequencing, was isolated from a seleniferous agricultural evaporation pond sediment collected in the Tulare Lake Drainage District, California. In cultures exposed to the atmosphere, the organism reduces selenate (SeO4(2-)) and selenite (SeO3(2-)) to red amorphous elemental selenium (Se degrees ) only upon reaching stationary phase, when O2 levels are less than 0.1 mg l(-1). In 48 h, S. maltophilia removed 81.2% and 99.8% of added SeO4(2-) and SeO3(2-) (initial concentration of 0.5 mM), respectively, from solution. Anaerobic growth experiments revealed that the organism was incapable of using SeO4(2-), SeO3(2-), SO4(2-) or NO3- as a terminal electron acceptor. Transmission electron microscopy of cultures spiked with either Se oxyanion were found to contain spherical extracellular deposits. Analysis of the deposits by energy-dispersive X-ray spectroscopy revealed that they consist of Se. Furthermore, S. maltophilia was active in producing volatile alkylselenides when in the presence of SeO4(2-) and SeO3(2-). The volatile products were positively identified as dimethyl selenide (DMSe), dimethyl selenenyl sulphide (DMSeS) and dimethyl diselenide (DMDSe) by gas chromatography-mass spectrometry. Our findings suggest that this bacterium may contribute to the biogeochemical cycling of Se in seleniferous evaporation pond sediments and waters. This organism may also be potentially useful in a bioremediation scheme designed to treat seleniferous agricultural wastewater. PMID:12662176

Dungan, Robert S; Yates, Scott R; Frankenberger, William T

2003-04-01

33

Characterization of salt-tolerant glutaminase from Stenotrophomonas maltophilia NYW-81 and its application in Japanese soy sauce fermentation  

Microsoft Academic Search

Glutaminase from Stenotrophomonas maltophilia NYW-81 was purified to homogeneity with a final specific activity of 325 U\\/mg. The molecular mass of the native enzyme was\\u000a estimated to be 41 kDa by gel filtration. A subunit molecular mass of 36 kDa was measured with SDS-PAGE, thus indicating that\\u000a the native enzyme is a monomer. The N-terminal amino acid sequence of the enzyme was determined

Mamoru Wakayama; Tomohiro Yamagata; Aki Kamemura; Nitaya Bootim; Shigekazu Yano; Takashi Tachiki; Kazuaki Yoshimune; Mitsuaki Moriguchi

2005-01-01

34

Isolation and characterization of a novel strain of Stenotrophomonas maltophilia possessing various dioxygenases for monocyclic hydrocarbon degradation  

PubMed Central

A Gram-negative bacterium, designated as strain KB2, was isolated from activated sludge and was found to utilize different aromatic substrates as sole carbon and energy source. On the basis of morphological and physiochemical characteristics and 16S rRNA gene sequence analysis, the isolated strain KB2 was identified as Stenotrophomonas maltophilia. Strain KB2 is from among different Stenotrophomonas maltophilia strains the first one described as exhibiting the activities of three types of dioxygenases depending on the structure of the inducer. The cells grown on benzoate and catechol showed mainly catechol 1,2-dioxygenase activity. The activity of 2,3-dioxygenase was detected after phenol induction. Protocatechuate 3,4-dioxygenase was found in crude cell extracts of this strain after incubation with 4-hydroxybenzoic acid, protocatechuic acid and vanillic acid. Because of broad spectrum of dioxygenases’ types that Stenotrophomonas maltophilia KB2 can exhibit, this strain appears to be very powerful and useful tool in the biotreatment of wastewaters and in soil decontamination. PMID:24031359

Urszula, Guzik; Izabela, Gren; Danuta, Wojcieszynska; Sylwia, Labuzek

2009-01-01

35

Cloning and Characterization of SmeDEF, a Novel Multidrug Efflux Pump from Stenotrophomonas maltophilia  

PubMed Central

Stenotrophomonas maltophilia is a nosocomial bacterial pathogen intrinsically resistant to several antibiotics. The mechanisms involved in this intrinsic multiresistance phenotype are poorly understood. A library of chromosomal DNA from a spontaneous multidrug-resistant S. maltophilia D457R mutant (A. Alonso and J. L. Martinez, Antimicrob. Agents Chemother. 41:1140–1142, 1997) was screened for complementation of erythromycin susceptibility on an antibiotic-hypersusceptible Escherichia coli ?acrAB strain. Cloning and further analysis revealed that a 6-kbp region constituting a transcriptional unit was capable of complementing the antibiotic-susceptible phenotype of an E. coli ?acrAB strain. We identified three open reading frames, smeD, smeE and smeF, which code for members of the membrane fusion protein, resistance nodulation division, and outer membrane factor families, respectively. Drug susceptibility assays indicated that the SmeDEF system cloned in E. coli mediates resistance to a wide range of antibiotics. Ethidium bromide and norfloxacin accumulation experiments in the presence and in the absence of carbonyl cyanide m-chlorophenylhydrazone showed that this system constitutes a drug efflux pump dependent on the membrane proton motive force. The presence of high levels of smeDEF mRNA in the multiresistant D457R mutant was consistent with the high levels of SmeF (formerly Omp54) observed in the same strain. In contrast, transcription levels of smeDEF in the D457 strain were tiny, which correlates with the low levels of SmeF observed for this strain. Also, for both the D457 and D457R strains, we observed growth phase-dependent regulation in which the highest level of transcription corresponded to early exponential phase, with transcription decreasing throughout the growth curve to undetectable levels at 24 h. PMID:11036026

Alonso, Ana; Martinez, Jose L.

2000-01-01

36

NagZ-dependent and NagZ-independent mechanisms for ?-lactamase expression in Stenotrophomonas maltophilia.  

PubMed

?-N-Acetylglucosaminidase (NagZ), encoded by the nagZ gene, is a critical enzyme for basal-level ampC derepression (ampC expression in the absence of ?-lactam challenge) in ampD and dacB mutants of Pseudomonas aeruginosa. Three mutants with a phenotype of basal-level L1 and L2 ?-lactamase derepression in Stenotrophomonas maltophilia have been reported, including KJ?DI (ampD(I) mutant), KJ?mrcA (mrcA mutant), and KJ?DI?mrcA (ampD(I) and mrcA double mutant). In this study, nagZ of S. maltophilia was characterized, and its roles in basal-level ?-lactamase derepression, induced ?-lactamase activities, and ?-lactam resistance of KJ?DI, KJ?mrcA, and KJ?DI?mrcA were evaluated. Expression of the nagZ gene was constitutive and not regulated by AmpR, AmpD(I), AmpN, AmpG, PBP1a, and NagZ. Introduction of ?nagZ into KJ?DI nearly abolished basal-level derepressed ?-lactamase activity; conversely, introduction of ?nagZ into KJ?mrcA did not affect it. At least two activator ligands (ALs) are thus considered responsible for ?-lactamase expression in the S. maltophilia system, specifically, the NagZ-dependent (AL1) and NagZ-independent (AL2) ligands responsible for the basal-level derepressed ?-lactamase activities of KJ?DI and KJ?mrcA, respectively. The contributions of AL1 and AL2 to the induced ?-lactamase activities may vary with the types of ?-lactams. nagZ inactivation did not affect aztreonam-, cefoxitin-, and carbenicillin-induced ?-lactamase activities, but it attenuated cefuroxime- and piperacillin-induced ?-lactamase activities. Introduction of ?nagZ into KJ, KJ?DI, KJ?mrcA, and KJ?DI?mrcA did not significantly change the MICs of the ?-lactams tested except that the MICs of cefuroxime and piperacillin moderately decreased in strains KJ?Z and KJ?DI?Z (nagZ mutants). PMID:22252801

Huang, Yi-Wei; Hu, Rouh-Mei; Lin, Cheng-Wen; Chung, Tung-Ching; Yang, Tsuey-Ching

2012-04-01

37

Chitooligosaccharides are converted to N-acetylglucosamine by N-acetyl-?-hexosaminidase from Stenotrophomonas maltophilia.  

PubMed

The Stenotrophomonas maltophilia k279a (Stm) Hex gene encodes a polypeptide of 785 amino acid residues, with an N-terminal signal peptide. StmHex was cloned without signal peptide and expressed as an 83.6 kDa soluble protein in Escherichia coli BL21 (DE3). Purified StmHex was optimally active at pH 5.0 and 40 °C. The Vmax, Km and kcat/Km for StmHex towards chitin hexamer were 10.55 nkat (mg protein)(-1), 271 ?M and 0.246 s(-1) mM(-1), while the kinetic values with chitobiose were 30.65 nkat (mg protein)(-1), 2365 ?M and 0.082 s(-1) mM(-1), respectively. Hydrolytic activity on chitooligosaccharides indicated that StmHex was an exo-acting enzyme and yielded N-acetyl-D-glucosamine (GlcNAc) as the final product. StmHex hydrolysed chitooligosaccharides (up to hexamer) into GlcNAc within 60 min, suggesting that this enzyme has potential for use in large-scale production of GlcNAc from chitooligosaccharides. PMID:23965017

Katta, Suma; Ankati, Sravani; Podile, Appa Rao

2013-11-01

38

Biosorption and biodegradation of triphenyltin by Stenotrophomonas maltophilia and their influence on cellular metabolism.  

PubMed

Triphenyltin (TPT), an endocrine disruptor, is polluting the global environment through its worldwide use. However, information concerning the mechanisms of TPT biodegradation and cellular metabolism is severely limited. Therefore, these processes were elucidated through experiments involving TPT biosorption and degradation, intracellular metabolite analysis, nutrient use, ion and monosaccharide release, cellular membrane permeability and protein concentration quantification. The results verified that TPT was initially adsorbed by the cell surface of Stenotrophomonas maltophilia and was subsequently transported and degraded intracellularly with diphenyltin and monophenyltin production. Cl(-), Na(+), arabinose and glucose release, membrane permeability and the extracellular protein concentration increased during TPT treatment, whereas K(+) and PO4(3-) utilization and intracellular protein concentration declined. The biosorption, degradation and removal efficiencies of TPT at 0.5mgL(-1) by 0.3gL(-1) viable cells at 10 d were 3.8, 77.8 and 86.2%, respectively, and the adsorption efficiency by inactivated cells was 72.6%. PMID:24866561

Gao, Jiong; Ye, Jinshao; Ma, Jiawen; Tang, Litao; Huang, Jie

2014-07-15

39

Clinical Factors Associated with Acquisition of Resistance to Levofloxacin in Stenotrophomonas maltophilia  

PubMed Central

Purpose Fluoroquinolones, rapidly gaining prominence in treatment of Stenotrophomonas maltophilia (SMP), are noted for their potency and tolerability. However, SMP may rapidly acquire resistance to fluoroquinolones. We evaluated associations of clinical factors with acquisition of levofloxacin resistance (LFr) in SMP. Materials and Methods Our retrospective cohort study was based on patient data collected between January 2008 and June 2010. Through screening of 1275 patients, we identified 122 patients with data for SMP antibiotic susceptibility testing in ?3 serial SMP isolates. Results We assigned the 122 patients to either the SS group (n=54) in which levofloxacin susceptibility was maintained or the SR group (n=31) in which susceptible SMP acquired resistance. In multivariate regression analysis, exposure to levofloxacin for more than 3 weeks [odds ratio (OR) 15.39, 95% confidential interval (CI) 3.08-76.93, p=0.001] and co-infection or co-colonization with Klebsiella pneumoniae resistant to levofloxacin (OR 4.85, 95% CI 1.16-20.24, p=0.030) were independently associated with LFr acquisition in SMP. Conclusion Acquisition of LFr during serial sampling of SMP was related to the levofloxacin exposure. PMID:24954328

Baek, Ji Hyeon; Kim, Chang Oh; Jeong, Su Jin; Ku, Nam Soo; Choi, Jun Yong; Yong, Dongeun; Song, Young Goo; Lee, Kyungwon; Kim, June Myung

2014-01-01

40

Extracellular serine proteases from Stenotrophomonas maltophilia: Screening, isolation and heterologous expression in E. coli.  

PubMed

A large strain collection comprising antagonistic bacteria was screened for novel detergent proteases. Several strains displayed protease activity on agar plates containing skim milk but were inactive in liquid media. Encapsulation of cells in alginate beads induced protease production. Stenotrophomonas maltophilia emerged as best performer under washing conditions. For identification of wash-active proteases, four extracellular serine proteases called StmPr1, StmPr2, StmPr3 and StmPr4 were cloned. StmPr2 and StmPr4 were sufficiently overexpressed in E. coli. Expression of StmPr1 and StmPr3 resulted in unprocessed, insoluble protein. Truncation of most of the C-terminal domain which has been identified by enzyme modeling succeeded in expression of soluble, active StmPr1 but failed in case of StmPr3. From laundry application tests StmPr2 turned out to be a highly wash-active protease at 45°C. Specific activity of StmPr2 determined with suc-L-Ala-L-Ala-L-Pro-l-Phe-p-nitroanilide as the substrate was 17±2U/mg. In addition we determined the kinetic parameters and cleavage preferences of protease StmPr2. PMID:21983234

Ribitsch, D; Heumann, S; Karl, W; Gerlach, J; Leber, R; Birner-Gruenberger, R; Gruber, K; Eiteljoerg, I; Remler, P; Siegert, P; Lange, J; Maurer, K H; Berg, G; Guebitz, G M; Schwab, H

2012-01-01

41

Stenotrophomonas maltophilia Encodes a Type II Protein Secretion System That Promotes Detrimental Effects on Lung Epithelial Cells  

PubMed Central

The Gram-negative bacterium Stenotrophomonas maltophilia is increasingly identified as a multidrug-resistant pathogen, being associated with pneumonia, among other infections. Despite this increasing clinical problem, the genetic and molecular basis of S. maltophilia virulence is quite minimally defined. We now report that strain K279a, the first clinical isolate of S. maltophilia to be sequenced, encodes a functional type II protein secretion (T2S) system. Indeed, mutants of K279a that contain a mutation in the xps locus exhibit a loss of at least seven secreted proteins and three proteolytic activities. Unlike culture supernatants from the parental K279a, supernatants from multiple xps mutants also failed to induce the rounding, detachment, and death of A549 cells, a human lung epithelial cell line. Supernatants of the xps mutants were also unable to trigger a massive rearrangement in the host cell's actin cytoskeleton that was associated with K279a secretion. In all assays, a complemented xpsF mutant behaved as the wild type did, demonstrating that Xps T2S is required for optimal protein secretion and the detrimental effects on host cells. The activities that were defined as being Xps dependent in K279a were evident among other respiratory isolates of S. maltophilia. Utilizing a similar type of genetic analysis, we found that a second T2S system (Gsp) encoded by the K279a genome is cryptic under all of the conditions tested. Overall, this study represents the first examination of T2S in S. maltophilia, and the data obtained indicate that Xps T2S likely plays an important role in S. maltophilia pathogenesis. PMID:23774603

Karaba, Sara M.; White, Richard C.

2013-01-01

42

The Impact of spgM, rpfF, rmlA Gene Distribution on Biofilm Formation in Stenotrophomonas maltophilia  

PubMed Central

Background Stenotrophomonas maltophilia is emerging as one of the most frequently found bacteria in chronic pulmonary infection. Biofilm is increasingly recognized as a contributing factor to disease pathogenesis. In the present study, a total of 37 isolates of S. maltophilia obtained from chronic pulmonary infection patients were evaluated to the relationship between biofilm production and the relative genes expression. Methods The clonal relatedness of isolates was determined by pulse-field gel electrophoresis. Biofilm formation assays were performed by crystal violet assay, and confirmed by Electron microscopy analysis and CLSM analysis. PCR was employed to learn gene distribution and expression. Results Twenty-four pulsotypes were designated for 37 S. maltophilia isolates, and these 24 pulsotypes exhibited various levels of biofilm production, 8 strong biofilm-producing S. maltophilia strains with OD492 value above 0.6, 14 middle biofilm-producing strains with OD492 average value of 0.4 and 2 weak biofilm-producing strains with OD492 average value of 0.19. CLSM analysis showed that the isolates from the early stage of chronic infection enable to form more highly structured and multilayered biofim than those in the late stage. The prevalence of spgM, rmlA, and rpfF genes was 83.3%, 87.5%, and 50.0% in 24 S. maltophilia strains, respectively, and the presence of rmlA, spgM or rpfF had a close relationship with biofilm formation but did not significantly affect the mean amount of biofilm. Significant mutations of spgM and rmlA were found in both strong and weak biofilm-producing strains. Conclusion Mutations in spgM and rmlA may be relevant to biofilm formation in the clinical isolates of S. maltophilia. PMID:25285537

Zhuo, Chao; Zhao, Qian-yu; Xiao, Shu-nian

2014-01-01

43

Role of Excessive Inflammatory Response to Stenotrophomonas maltophilia Lung Infection in DBA/2 Mice and Implications for Cystic Fibrosis?  

PubMed Central

Stenotrophomonas maltophilia is a pathogen that causes infections mainly in immunocompromised patients. Despite increased S. maltophilia isolation from respiratory specimens of patients with cystic fibrosis (CF), the real contribution of the microorganism to CF pathogenesis still needs to be clarified. The aim of the present study was to evaluate the pathogenic role of S. maltophilia in CF patients by using a model of acute respiratory infection in DBA/2 mice following a single exposure to aerosolized bacteria. The pulmonary bacterial load was stable until day 3 and then decreased significantly from day 3 through day 14, when the bacterial load became undetectable in all infected mice. Infection disseminated in most mice, although at a very low level. Severe effects (swollen lungs, large atelectasis, pleural adhesion, and hemorrhages) of lung pathology were observed on days 3, 7, and 14. The clearance of S. maltophilia observed in DBA/2 mouse lungs was clearly associated with an early and intense bronchial and alveolar inflammatory response, which is mediated primarily by neutrophils. Significantly higher levels of interleukin-1? (IL-1?), IL-6, IL-12, gamma interferon (IFN-?), tumor necrosis factor alpha (TNF-?), GRO?/KC, MCP-1/JE, MCP-5, macrophage inflammatory protein 1? (MIP-1?), MIP-2, and TARC were observed in infected mice on day 1 with respect to controls. Excessive pulmonary infection and inflammation caused systemic effects, manifested by weight loss, and finally caused a high mortality rate. Taken together, our results show that S. maltophilia is not just a bystander in CF patients but has the potential to contribute to the inflammatory process that compromises respiratory function. PMID:20308302

Di Bonaventura, Giovanni; Pompilio, Arianna; Zappacosta, Roberta; Petrucci, Francesca; Fiscarelli, Ersilia; Rossi, Cosmo; Piccolomini, Raffaele

2010-01-01

44

Crystallization of the N-terminal regulatory domain of the enhancer-binding protein FleQ from Stenotrophomonas maltophilia.  

PubMed

FleQ is a master regulator that controls bacterial flagellar gene expression. It is a unique enhancer-binding protein or repressor protein comprising an N-terminal FleQ domain, an AAA(+)/ATPase ?54-interaction domain and a helix-turn-helix DNA-binding domain. FleN is a putative ATPase with a deviant Walker A motif that works together with FleQ by binding to the FleQ N-terminal domain to fully express pel, psl and cdr operons in the presence of c-di-GMP to enhance biofilm formation. Stenotrophomonas maltophilia is an emerging human pathogen that causes fatal infections in humans. In order to understand the interaction between the FleN and FleQ domains and its effect on S. maltophilia biofilm formation, determination of the FleQ-c-di-GMP and FleN-FleQ-c-di-GMP complex structures was embarked upon. Towards this goal, the FleQ N-terminal domain from S. maltophilia was first cloned and expressed in Escherichia coli. Native and SeMet-labelled FleQ domains were successfully crystallized and diffracted to resolutions of 2.08 and 2.58?Å, respectively. PMID:24598919

Yang, Jauo-Guey; Shih, Min-Shao; Kuo, Wei-Ting; Chin, Ko-Hsin; Shen, Gwan-Han; Chou, Shan-Ho

2014-03-01

45

Phenotypic and genotypic characterization of Stenotrophomonas maltophilia isolates from patients with cystic fibrosis: Genome diversity, biofilm formation, and virulence  

PubMed Central

Background Stenotrophomonas maltophilia is emerging as one of the most frequently found bacteria in cystic fibrosis (CF) patients. In the present study, phenotypic and genotypic traits of a set of 98 isolates of S. maltophilia obtained from clinical (CF and non-CF patients) and environmental sources were comparatively evaluated. Results S. maltophilia exhibited a high level of genomic diversity in both CF and non-CF group, thus possibly allowing this bacterium to expand its pathogenic potentials. Strains sharing the same pulsotype infected different patients, thus likely indicating the occurrence of clonal spread or acquisition by a common source. CF isolates differed greatly in some phenotypic traits among each other and also when compared with non-CF isolates, demonstrating increased mean generation time and susceptibility to oxidative stress, but reduced ability in forming biofilm. Furthermore, in CF isolates flagella- and type IV pili-based motilities were critical for biofilm development, although not required for its initiation. Sequential isogenic strains isolated from the same CF patient displayed heterogeneity in biofilm and other phenotypic traits during the course of chronic infection. CF and non-CF isolates showed comparable virulence in a mouse model of lung infection. Conclusions Overall, the phenotypic differences observed between CF and non-CF isolates may imply different selective conditions and persistence (adaptation) mechanisms in a hostile and heterogeneous environment such as CF lung. Molecular elucidation of these mechanisms will be essential to better understand the selective adaptation in CF airways in order to design improved strategies useful to counteract and eradicate S. maltophilia infection. PMID:21729271

2011-01-01

46

A function of SmeDEF, the major quinolone resistance determinant of Stenotrophomonas maltophilia, is the colonization of plant roots.  

PubMed

Quinolones are synthetic antibiotics, and the main cause of resistance to these antimicrobials is mutation of the genes encoding their targets. However, in contrast to the case for other organisms, such mutations have not been found in quinolone-resistant Stenotrophomonas maltophilia isolates, in which overproduction of the SmeDEF efflux pump is a major cause of quinolone resistance. SmeDEF is chromosomally encoded and highly conserved in all studied S. maltophilia strains; it is an ancient element that evolved over millions of years in this species. It thus seems unlikely that its main function would be resistance to quinolones, a family of synthetic antibiotics not present in natural environments until the last few decades. Expression of SmeDEF is tightly controlled by the transcriptional repressor SmeT. Our work shows that plant-produced flavonoids can bind to SmeT, releasing it from smeDEF and smeT operators. Antibiotics extruded by SmeDEF do not impede the binding of SmeT to DNA. The fact that plant-produced flavonoids specifically induce smeDEF expression indicates that they are bona fide effectors regulating expression of this resistance determinant. Expression of efflux pumps is usually downregulated unless their activity is needed. Since smeDEF expression is triggered by plant-produced flavonoids, we reasoned that this efflux pump may have a role in the colonization of plants by S. maltophilia. Our results showed that, indeed, deletion of smeE impairs S. maltophilia colonization of plant roots. Altogether, our results indicate that quinolone resistance is a recent function of SmeDEF and that colonization of plant roots is likely one original function of this efflux pump. PMID:24837376

García-León, Guillermo; Hernández, Alvaro; Hernando-Amado, Sara; Alavi, Peyman; Berg, Gabriele; Martínez, José Luis

2014-08-01

47

Involvement of Mutation in ampD I, mrcA, and at Least One Additional Gene in ?-Lactamase Hyperproduction in Stenotrophomonas maltophilia  

PubMed Central

It has been reported that targeted disruption of ampD I or mrcA causes ?-lactamase hyperproduction in Stenotrophomonas maltophilia. We show here that ?-lactamase-hyperproducing laboratory selected mutants and clinical isolates can have wild-type ampD I and mrcA genes, implicating mutation of at least one additional gene in this phenotype. The involvement of mutations at multiple loci in the activation of ?-lactamase production in S. maltophilia reveals that there are significant deviations from the enterobacterial paradigm of AmpR-mediated control of ?-lactamase induction. We do show, however, that S. maltophilia ampD I can complement a mutation in Escherichia coli ampD. This suggests that an anhydromuropeptide degradation product of peptidoglycan is used to activate AmpR in S. maltophilia, as is also the case in enteric bacteria. PMID:23979761

Talfan, Asmaa; Mounsey, Oliver; Charman, Matthew; Townsend, Eleanor

2013-01-01

48

Heavy Metal Tolerance in Stenotrophomonas maltophilia Delphine Pages1,2,3  

E-print Network

& Microbiol Enviro, Saint-Paul-lez-Durance, France, 3 Aix-Marseille Universite´, Saint of biopesticides [5]. S. maltophilia is also able to degrade xenobiotic compounds [6,7], to detoxify high molecular

Paris-Sud XI, Université de

49

A Linkage between SmeIJK Efflux Pump, Cell Envelope Integrity, and ?E-Mediated Envelope Stress Response in Stenotrophomonas maltophilia  

PubMed Central

Resistance nodulation division (RND) efflux pumps, such as the SmeIJK pump of Stenotrophomonas maltophilia, are known to contribute to the multidrug resistance in Gram-negative bacteria. However, some RND pumps are constitutively expressed even though no antimicrobial stresses occur, implying that there should be some physical implications for these RND pumps. In this study, the role of SmeIJK in antimicrobials resistance, envelope integrity, and ?E-mediated envelope stress response (ESR) of S. maltophilia was assessed. SmeIJK was involved in the intrinsic resistance of S. maltophilia KJ to aminoglycosides and leucomycin. Compared with the wild-type KJ, the smeIJK deletion mutant exhibited growth retardation in the MH medium, an increased sensitivity to membrane-damaging agents (MDAs), as well as activation of an ?E-mediated ESR. Moreover, the expression of smeIJK was further induced by sub-lethal concentrations of MDAs or surfactants in an ?E-dependent manner. These data collectively suggested an alternative physiological role of smeIJK in cell envelope integrity maintenance and ?E-mediated ESR beyond the efflux of antibiotics. Because of the necessity of the physiological role of SmeIJK in protecting S. maltophilia from the envelope stress, smeIJK is constitutively expressed, which, in turn, contributes the intrinsic resistance to aminoglycoside and leucomycin. This is the first demonstration of the linkage among RND-type efflux pump, cell envelope integrity, and ?E-mediated ESR in S. maltophilia. PMID:25390933

Huang, Yi-Wei; Liou, Rung-Shiuan; Lin, Yi-Tsung; Huang, Hsin-Hui; Yang, Tsuey-Ching

2014-01-01

50

Persistent Organic Pollutants Induced Protein Expression and Immunocrossreactivity by Stenotrophomonas maltophilia PM102: A Prospective Bioremediating Candidate  

PubMed Central

A novel bacterium capable of growth on trichloroethylene as the sole carbon source was identified as Stenotrophomonas maltophilia PM102 by 16S rDNA sequencing (accession number of NCBI GenBank: JQ797560). In this paper, we report the growth pattern, TCE degradation, and total proteome of this bacterium in presence of various other carbon sources: toluene, phenol, glucose, chloroform, and benzene. TCE degradation was comparatively enhanced in presence of benzene. Densitometric analysis of the intracellular protein profile revealed four proteins of 78.6, 35.14, 26.2, and 20.47?kDa while the extracellular protein profile revealed two distinct bands at 14?kDa and 11?kDa that were induced by TCE, benzene, toluene, and chloroform but absent in the glucose lane. A rabbit was immunised with the total protein extracted from the bacteria grown in 0.2% TCE + 0.2% peptone. Antibody preadsorbed on proteins from peptone grown PM102 cells reacted with a single protein of 35.14?kDa (analysed by MALDI-TOF-mass-spectrometry) from TCE, benzene, toluene, or chloroform grown cells. No reaction was seen for proteins of PM102 grown with glucose. The PM102 strain was immobilised in calcium alginate beads, and TCE degradation by immobilised cells was almost double of that by free cells. The beads could be reused 8 times. PMID:23878815

Mukherjee, Piyali; Roy, Pranab

2013-01-01

51

A Patient Presenting with Cholangitis due to Stenotrophomonas Maltophilia and Pseudomonas Aeruginosa Successfully Treated with Intrabiliary Colistine  

PubMed Central

Anatomical barriers for antibiotic penetration can pose a particular challenge in the clinical setting. Stenotrophomonas maltophilia (SM) and Pseudomonas aeruginosa (PA) are two pathogens capable of developing multiple drug-resistance (MDR) mechanisms. We report the case of a 56-year-old female patient with a permanent percutaneous transhepatic biliary drainage (PTBD), who was admitted to our hospital with a cholangitis due to a MDR Escherichia coli strain. Upon admission, culture-guided antimicrobial therapy was conducted and the biliary catheter was replaced, with poor clinical response. Subsequently, SM and PA were detected. Treatment with fosfomycin and colistine was initiated, again without adequate response. Systemic colistine and tigecycline along with an intrabiliary infusion of colistine for 5 days was then used, followed by parenteral fosfomycin and tigecycline for 7 days. The patient was then successfully discharged. This is the first case report we are aware of on the use of intrabiliary colistine. It describes a new approach to treating cholangitis by MDR bacteria in patients with a PTBD. PMID:25002957

Perez, Pablo N.; Ramirez, Maria A.; Fernandez, Jose A.; de Guevara, Laura Ladron

2014-01-01

52

Plasmid location and molecular heterogeneity of the L1 and L2 beta-lactamase genes of Stenotrophomonas maltophilia.  

PubMed

An approximately 200-kb plasmid has been purified from clinical isolates of Stenotrophomonas maltophilia. This plasmid was found in all of the 10 isolates examined and contains both the L1 and the L2 beta-lactamase genes. The location of L1 and L2 on a plasmid makes it more likely that they could spread to other gram-negative bacteria, potentially causing clinical problems. Sequence analysis of the 10 L1 genes revealed three novel genes, L1c, L1d, and L1e, with 8, 12, and 20% divergence from the published strain IID 1275 L1 (L1a), respectively. The most unusual L1 enzyme (L1e) displayed markedly different kinetic properties, with respect to hydrolysis of nitrocefin and imipenem, compared to those of L1a (250- and 100-fold lower k(cat)/K(m) ratios respectively). L1c and L1d, in contrast, displayed levels of hydrolysis very similar to that of L1a. Several nonconservative amino acid differences with respect to L1a, L1b, L1c, and L1d were observed in the substrate binding-catalytic regions of L1e, and this could explain the kinetic differences. Three novel L2 genes (L2b, L2c, and L2d) were sequenced from the same isolates, and their sequences diverge from the published sequence of strain IID 1275 L2 (L2a) by 4, 9, and 25%, respectively. Differences in L1 and L2 gene sequences were not accompanied by similar divergences in 16S rRNA gene sequences, for which differences of <1% were found. It is therefore apparent that the L1 and L2 genes have evolved relatively quickly, perhaps because of their presence on a plasmid. PMID:11158734

Avison, M B; Higgins, C S; von Heldreich, C J; Bennett, P M; Walsh, T R

2001-02-01

53

Risk Factors and Outcomes of Stenotrophomonas maltophilia Bacteraemia: A Comparison with Bacteraemia Caused by Pseudomonas aeruginosa and Acinetobacter Species  

PubMed Central

Stenotrophomonas maltophilia (SM) is an important nosocomial pathogen that exhibits intrinsic resistance to various antimicrobial agents. However, the risk factors for SM bacteraemia have not been sufficiently evaluated. From January 2005 to September 2012, we retrospectively compared the clinical backgrounds and outcomes of SM bacteraemic patients (SM group) with those of bacteraemic patients due to Pseudomonas aeruginosa (PA group) or Acinetobacter species (AC group). DNA genotyping of the SM isolates using the Diversilab system was performed to investigate the genetic relationships among the isolates. The SM, PA, and AC groups included 54, 167, and 69 patients, respectively. Nine of 17 patients in the SM group receiving trimethoprim-sulfamethoxazole prophylaxis developed SM bacteraemia. Independent risk factors for SM bacteraemia were the use of carbapenems and antipseudomonal cephalosporins and SM isolation within 30 days prior to the onset of bacteraemia. Earlier SM isolation was observed in 32 of 48 patients (66.7%) with SM bacteraemia who underwent clinical microbiological examinations. Of these 32 patients, 15 patients (46.9%) had the same focus of bacteraemia as was found in the previous isolation site. The 30-day all-cause mortality rate among the SM group (33.3%) was higher than that of the PA group (21.5%, p?=?0.080) and the AC group (17.3%, p?=?0.041). The independent factor that was associated with 30-day mortality was the SOFA score. DNA genotyping of SM isolates and epidemiological data suggested that no outbreak had occurred. SM bacteraemia was associated with high mortality and should be considered in patients with recent use of broad-spectrum antibiotics or in patients with recent isolation of the organism. PMID:25375244

Hotta, Go; Matsumura, Yasufumi; Kato, Karin; Nakano, Satoshi; Yunoki, Tomoyuki; Yamamoto, Masaki; Nagao, Miki; Ito, Yutaka; Takakura, Shunji; Ichiyama, Satoshi

2014-01-01

54

Antibacterial and Cytotoxic Efficacy of Extracellular Silver Nanoparticles Biofabricated from Chromium Reducing Novel OS4 Strain of Stenotrophomonas maltophilia  

PubMed Central

Biofabricated metal nanoparticles are generally biocompatible, inexpensive, and ecofriendly, therefore, are used preferably in industries, medical and material science research. Considering the importance of biofabricated materials, we isolated, characterized and identified a novel bacterial strain OS4 of Stenotrophomonas maltophilia (GenBank: JN247637.1). At neutral pH, this Gram negative bacterial strain significantly reduced hexavalent chromium, an important heavy metal contaminant found in the tannery effluents and minings. Subsequently, even at room temperature the supernatant of log phase grown culture of strain OS4 also reduced silver nitrate (AgNO3) to generate nanoparticles (AgNPs). These AgNPs were further characterized by UV–visible, Nanophox particle size analyzer, XRD, SEM and FTIR. As evident from the FTIR data, plausibly the protein components of supernatant caused the reduction of AgNO3. The cuboid and homogenous AgNPs showed a characteristic UV-visible peak at 428 nm with average size of ?93 nm. The XRD spectra exhibited the characteristic Bragg peaks of 111, 200, 220 and 311 facets of the face centred cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. From the nanoparticle release kinetics data, the rapid release of AgNPs was correlated with the particle size and increasing surface area of the nanoparticles. A highly significant antimicrobial activity against medically important bacteria by the biofabricated AgNPs was also revealed as decline in growth of Staphylococcus aureus (91%), Escherichia coli (69%) and Serratia marcescens (66%) substantially. Additionally, different cytotoxic assays showed no toxicity of AgNPs to liver function, RBCs, splenocytes and HeLa cells, hence these particles were safe to use. Therefore, this novel bacterial strain OS4 is likely to provide broad spectrum benefits for curing chromium polluted sites, for biofabrication of AgNPs and ultimately in the nanoparticle based drug formulation for the treatment of infectious diseases. PMID:23555625

Oves, Mohammad; Khan, Mohammad Saghir; Zaidi, Almas; Ahmed, Arham S.; Ahmed, Faheem; Ahmad, Ejaz; Sherwani, Asif; Owais, Mohammad; Azam, Ameer

2013-01-01

55

Antibacterial and cytotoxic efficacy of extracellular silver nanoparticles biofabricated from chromium reducing novel OS4 strain of Stenotrophomonas maltophilia.  

PubMed

Biofabricated metal nanoparticles are generally biocompatible, inexpensive, and ecofriendly, therefore, are used preferably in industries, medical and material science research. Considering the importance of biofabricated materials, we isolated, characterized and identified a novel bacterial strain OS4 of Stenotrophomonas maltophilia (GenBank: JN247637.1). At neutral pH, this Gram negative bacterial strain significantly reduced hexavalent chromium, an important heavy metal contaminant found in the tannery effluents and minings. Subsequently, even at room temperature the supernatant of log phase grown culture of strain OS4 also reduced silver nitrate (AgNO3) to generate nanoparticles (AgNPs). These AgNPs were further characterized by UV-visible, Nanophox particle size analyzer, XRD, SEM and FTIR. As evident from the FTIR data, plausibly the protein components of supernatant caused the reduction of AgNO3. The cuboid and homogenous AgNPs showed a characteristic UV-visible peak at 428 nm with average size of ~93 nm. The XRD spectra exhibited the characteristic Bragg peaks of 111, 200, 220 and 311 facets of the face centred cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. From the nanoparticle release kinetics data, the rapid release of AgNPs was correlated with the particle size and increasing surface area of the nanoparticles. A highly significant antimicrobial activity against medically important bacteria by the biofabricated AgNPs was also revealed as decline in growth of Staphylococcus aureus (91%), Escherichia coli (69%) and Serratia marcescens (66%) substantially. Additionally, different cytotoxic assays showed no toxicity of AgNPs to liver function, RBCs, splenocytes and HeLa cells, hence these particles were safe to use. Therefore, this novel bacterial strain OS4 is likely to provide broad spectrum benefits for curing chromium polluted sites, for biofabrication of AgNPs and ultimately in the nanoparticle based drug formulation for the treatment of infectious diseases. PMID:23555625

Oves, Mohammad; Khan, Mohammad Saghir; Zaidi, Almas; Ahmed, Arham S; Ahmed, Faheem; Ahmad, Ejaz; Sherwani, Asif; Owais, Mohammad; Azam, Ameer

2013-01-01

56

Modification of surface and enzymatic properties of Achromobacter denitrificans and Stenotrophomonas maltophilia in association with diesel oil biodegradation enhanced with alkyl polyglucosides.  

PubMed

The article concerns the influence of selected alkyl polyglucosides on biodegradation, cell surface and enzymatic properties of Stenotrophomonas maltophilia and Achromobacter denitrificans. The biodegradation of diesel oil depends on several factors including type and the amount of surfactant as well as bacterial genera used in the process. Nevertheless, a careful selection of these variables must be made as some bacterial strains prefer to use surfactants as their carbon source. This leads to the lowered biodegradation of diesel oil as can be observed for the tested S. maltophilia strain. Alkyl polyglucosides influenced the cell surface properties of both of the tested strains in slightly different ways. Especially for A. denitrificans, for which the hydrophobicity increased with concentration of both - Lutensol GD 70 and Glucopon 215 in diesel oil-surfactant systems. Moreover, judging by the efficiency of biodegradation, the most effective process was observed in the presence of Lutensol GD 70 (240 and 360mgL(-1)) with biodegradation rising from 32% (without surfactant) to 68%. No such relation was observed for S. maltophilia. PMID:23777790

Sa?ek, Karina; Zgo?a-Grze?kowiak, Agnieszka; Kaczorek, Ewa

2013-11-01

57

In Vitro Antibacterial and Antibiofilm Activities of Chlorogenic Acid against Clinical Isolates of Stenotrophomonas maltophilia including the Trimethoprim/Sulfamethoxazole Resistant Strain  

PubMed Central

The in vitro antibacterial and antibiofilm activity of chlorogenic acid against clinical isolates of Stenotrophomonas maltophilia was investigated through disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), time-kill and biofilm assays. A total of 9 clinical S. maltophilia isolates including one isolate resistant to trimethoprim/sulfamethoxazole (TMP/SMX) were tested. The inhibition zone sizes for the isolates ranged from 17 to 29?mm, while the MIC and MBC values ranged from 8 to 16??g mL?1 and 16 to 32??g mL?1. Chlorogenic acid appeared to be strongly bactericidal at 4x MIC, with a 2-log reduction in viable bacteria at 10?h. In vitro antibiofilm testing showed a 4-fold reduction in biofilm viability at 4x MIC compared to 1x MIC values (0.085 < 0.397 A 490?nm) of chlorogenic acid. The data from this study support the notion that the chlorogenic acid has promising in vitro antibacterial and antibiofilm activities against S. maltophilia. PMID:23509719

Karunanidhi, Arunkumar; Thomas, Renjan; van Belkum, Alex; Neela, Vasanthakumari

2013-01-01

58

Abundance of the Quorum-Sensing Factor Ax21 in Four Strains of Stenotrophomonas maltophilia Correlates with Mortality Rate in a New Zebrafish Model of Infection  

PubMed Central

Stenotrophomonas maltophilia is a Gram-negative pathogen with emerging nosocomial incidence. Little is known about its pathogenesis and the genomic diversity exhibited by clinical isolates complicates the study of pathogenicity and virulence factors. Here, we present a strategy to identify such factors in new clinical isolates of S. maltophilia, incorporating an adult-zebrafish model of S. maltophilia infection to evaluate relative virulence coupled to 2D difference gel electrophoresis to explore underlying differences in protein expression. In this study we report upon three recent clinical isolates and use the collection strain ATCC13637 as a reference. The adult-zebrafish model shows discrimination capacity, i.e. from very low to very high mortality rates, with clinical symptoms very similar to those observed in natural S. maltophilia infections in fish. Strain virulence correlates with resistance to human serum, in agreement with previous studies in mouse and rat and therefore supporting zebrafish as a replacement model. Despite its clinical origin, the collection strain ATCC13637 showed obvious signs of attenuation in zebrafish, with null mortality. Multilocus-sequence-typing analysis revealed that the most virulent strains, UV74 and M30, exhibit the strongest genetic similitude. Differential proteomic analysis led to the identification of 38 proteins with significantly different abundance in the three clinical strains relative to the reference strain. Orthologs of several of these proteins have been already reported to have a role in pathogenesis, virulence or resistance mechanisms thus supporting our strategy. Proof of concept is further provided by protein Ax21, whose abundance is shown here to be directly proportional to mortality in the zebrafish infection model. Indeed, recent studies have demonstrated that this protein is a quorum-sensing-related virulence factor. PMID:23840626

Yero, Daniel; Mongiardini, Elias; Torrent, Gerard; Huedo, Pol; Martinez, Paula; Roher, Nerea; Mackenzie, Simon; Gibert, Isidre; Daura, Xavier

2013-01-01

59

High activity catechol 1,2-dioxygenase from Stenotrophomonas maltophilia strain KB2 as a useful tool in cis,cis-muconic acid production.  

PubMed

This is the first report of a catechol 1,2-dioxygenase from Stenotrophomonas maltophilia strain KB2 with high activity against catechol and its methyl derivatives. This enzyme was maximally active at pH 8.0 and 40 °C and the half-life of the enzyme at this temperature was 3 h. Kinetic studies showed that the value of K m and V max was 12.8 ?M and 1,218.8 U/mg of protein, respectively. During our studies on kinetic properties of the catechol 1,2-dioxygenase we observed substrate inhibition at >80 ?M. The nucleotide sequence of the gene encoding the S. maltophilia strain KB2 catechol 1,2-dioxygenase has high identity with other catA genes from members of the genus Pseudomonas. The deduced 314-residue sequence of the enzyme corresponds to a protein of molecular mass 34.5 kDa. This enzyme was inhibited by competitive inhibitors (phenol derivatives) only by ca. 30 %. High tolerance against condition changes is desirable in industrial processes. Our data suggest that this enzyme could be of use as a tool in production of cis,cis-muconic acid and its derivatives. PMID:23536173

Guzik, Urszula; Hupert-Kocurek, Katarzyna; Sitnik, Ma?gorzata; Wojcieszy?ska, Danuta

2013-06-01

60

The Binding of Triclosan to SmeT, the Repressor of the Multidrug Efflux Pump SmeDEF, Induces Antibiotic Resistance in Stenotrophomonas maltophilia  

PubMed Central

The wide utilization of biocides poses a concern on the impact of these compounds on natural bacterial populations. Furthermore, it has been demonstrated that biocides can select, at least in laboratory experiments, antibiotic resistant bacteria. This situation has raised concerns, not just on scientists and clinicians, but also on regulatory agencies, which are demanding studies on the impact that the utilization of biocides may have on the development on resistance and consequently on the treatment of infectious diseases and on human health. In the present article, we explored the possibility that the widely used biocide triclosan might induce antibiotic resistance using as a model the opportunistic pathogen Stenotrophomonas maltophilia. Biochemical, functional and structural studies were performed, focusing on SmeDEF, the most relevant antibiotic- and triclosan-removing multidrug efflux pump of S. maltophilia. Expression of smeDEF is regulated by the repressor SmeT. Triclosan released SmeT from its operator and induces the expression of smeDEF, thus reducing the susceptibility of S. maltophilia to antibiotics in the presence of the biocide. The structure of SmeT bound to triclosan is described. Two molecules of triclosan were found to bind to one subunit of the SmeT homodimer. The binding of the biocide stabilizes the N terminal domain of both subunits in a conformation unable to bind DNA. To our knowledge this is the first crystal structure obtained for a transcriptional regulator bound to triclosan. This work provides the molecular basis for understanding the mechanisms allowing the induction of phenotypic resistance to antibiotics by triclosan. PMID:21738470

Romero, Antonio; Martinez, Jose L.

2011-01-01

61

Protocatechuate 3,4-dioxygenase: a wide substrate specificity enzyme isolated from Stenotrophomonas maltophilia KB2 as a useful tool in aromatic acid biodegradation.  

PubMed

Protocatechuate 3,4-dioxygenases (P34Os) catalyze the reaction of the ring cleavage of aromatic acid derivatives. It is a key reaction in many xenobiotic metabolic pathways. P34Os characterize narrow substrate specificity. This property is an unfavorable feature in the biodegradation process because one type of pollution is rarely present in the environment. Thus, the following study aimed at the characterization of a P34O from Stenotrophomonas maltophilia KB2, being able to utilize a wide spectrum of aromatic carboxylic acids. A total of 3 mM vanillic acid and 4-hydroxybenzoate were completely degraded during 8 and 4.5 h, respectively. When cells of strain KB2 were grown on 9 mM 4-hydroxybenzoate, P34O was induced. Biochemical analysis revealed that the examined enzyme was similar to other known P34Os, but showed untypical wide substrate specificity. A high activity of P34O against 2,4- and 3,5-dihydroxybenzoate was observed. As these substrates do not possess ortho configuration hydroxyl groups, it is postulated that their cleavage could be connected with their monodentate binding of substrate to the active site. Since this enzyme characterizes untypical wide substrate specificity it makes it a useful tool in applications for environmental clean-up purposes. PMID:24970342

Guzik, Urszula; Hupert-Kocurek, Katarzyna; Sitnik, Ma?gorzata; Wojcieszy?ska, Danuta

2014-01-01

62

Copper Enhanced Monooxygenase Activity and FT-IR Spectroscopic Characterisation of Biotransformation Products in Trichloroethylene Degrading Bacterium: Stenotrophomonas maltophilia PM102  

PubMed Central

Stenotrophomonas maltophilia PM102 (NCBI GenBank Acc. no. JQ797560) is capable of growth on trichloroethylene as the sole carbon source. In this paper, we report the purification and characterisation of oxygenase present in the PM102 isolate. Enzyme activity was found to be induced 10.3-fold in presence of 0.7?mM copper with a further increment to 14.96-fold in presence of 0.05?mM NADH. Optimum temperature for oxygenase activity was recorded at 36°C. The reported enzyme was found to have enhanced activity at pH 5 and pH 8, indicating presence of two isoforms. Maximum activity was seen on incubation with benzene compared to other substrates like TCE, chloroform, toluene, hexane, and petroleum benzene. Km and Vmax for benzene were 3.8?mM and 340?U/mg/min and those for TCE were 2.1?mM and 170?U/mg/min. The crude enzyme was partially purified by ammonium sulphate precipitation followed by dialysis. Zymogram analysis revealed two isoforms in the 70% purified enzyme fraction. The activity stain was more prominent when the native gel was incubated in benzene as substrate in comparison to TCE. Crude enzyme and purified enzyme fractions were assayed for TCE degradation by the Fujiwara test. TCE biotransformation products were analysed by FT-IR spectroscopy. PMID:24083236

Mukherjee, Piyali; Roy, Pranab

2013-01-01

63

A Cyclic AMP Receptor Protein-Regulated Cell-Cell Communication System Mediates Expression of a FecA Homologue in Stenotrophomonas maltophilia?  

PubMed Central

Stenotrophomonas maltophilia WR-C possesses an rpf/diffusible signal factor (DSF) cell-cell communication system. It produces cis-?2-11-methyl-dodecenoic acid, a DSF, and seven structural derivatives, which require rpfF and rpfB for synthesis. Acquisition of iron from the environment is important for bacterial growth as well as the expression of virulence genes. We identified a gene homologous to fecA, which encodes a ferric citrate receptor that transports exogenous siderophore ferric citrate from the environment into the bacterial periplasm. Western blot analysis with anti-FecA-His6 antibody showed that the FecA homologue was induced in the iron-depleted medium supplemented with a low concentration of ferric citrate. Deletion of rpfF or rpfB resulted in reduced FecA expression compared to the wild type. Synthetic DSF restored FecA expression by the ?rpfF mutant to the wild-type level. Reverse transcription-PCR showed that the fecA transcript was decreased in the ?rpfF mutant compared to the wild type. These data suggest that DSF affected the level of fecA mRNA. Transposon inactivation of crp, which encodes cyclic AMP (cAMP) receptor protein (CRP) resulted in reduced FecA expression and rpfF transcript level. Putative CRP binding sites were located upstream of the rpfF promoter, indicating that the effect of CRP on FecA is through the rpf/DSF pathway and by directly controlling rpfF. We propose that CRP may serve as a checkpoint for iron uptake, protease activity, and hemolysis in response to environmental changes such as changes in concentrations of glucose, cAMP, iron, or DSF. PMID:17574998

Huang, Tzu-Pi; Wong, Amy C. Lee

2007-01-01

64

Structure of Stenotrophomonas maltophilia FeoA complexed with zinc: a unique prokaryotic SH3--domain protein that possibly acts as a bacterial ferrous iron-transport activating factor  

PubMed Central

Iron is vital to the majority of prokaryotes, with ferrous iron believed to be the preferred form for iron uptake owing to its much better solubility. The major route for bacterial ferrous iron uptake is found to be via an Feo (ferrous iron-transport) system comprising the three proteins FeoA, FeoB and FeoC. Although the structure and function of FeoB have received much attention recently, the roles played by FeoA and FeoC have been little investigated to date. Here, the tertiary structure of FeoA from Stenotrophomonas maltophilia (Sm), a vital opportunistic pathogen in immunodepressed hosts, is reported. The crystal structure of SmFeoA has been determined to a resolution of 1.7?Å using an Se single-wavelength anomalous dispersion (Se-SAD) approach. Although SmFeoA bears low sequence identity to eukaryotic proteins, its structure is found to adopt a eukaryotic SH3-domain-like fold. It also bears weak similarity to the C-terminal SH3 domain of bacterial DtxR (diphtheria toxin regulator), with some unique characteristics. Intriguingly, SmFeoA is found to adopt a unique dimer cross-linked by two zinc ions and six anions (chloride ions). Since FeoB has been found to contain a G-protein-like domain with low GTPase activity, FeoA may interact with FeoB through the SH3–G-protein domain interaction to act as a ferrous iron-transport activating factor. PMID:20516589

Su, Yi-Che; Chin, Ko-Hsin; Hung, Hui-Chih; Shen, Gwan-Han; Wang, Andrew H.-J.; Chou, Shan-Ho

2010-01-01

65

Stenotrophomonas, Mycobacterium, and Streptomyces in home dust and air: associations with moldiness and other home/family characteristics  

EPA Science Inventory

Abstract Aims: (1) To investigate the dustborne and airborne bacterial concentrations of three emerging moisture-related bacteria: Stenotrophomonas maltophilia, Streptomyces, and Mycobacterium. (2) To study the association between these bacteria concentrations and Environmenta...

66

Stenotrophomonas Infection in a Patient with Glucose-6-Phosphate Dehydrogenase Deficiency  

PubMed Central

The drug of choice for treatment of Stenotrophomonas maltophilia is sulfamethoxazole/trimethoprim, and second-line therapy usually consists of a fluoroquinolone. However, in patients with glucose-6-phosphate dehydrogenase deficiency, neither sulfamethoxazole/trimethoprim nor a fluoroquinolone is a preferred option as it may result in hemolysis. Currently, there is a paucity of data regarding treatment of S maltophilia infection in these patients. This case report presents a patient who was successfully treated with doxycycline and inhaled colistimethate. PMID:23798908

Harthan, Aaron A.; Heger, Margaret L

2013-01-01

67

Stenotrophomonas afiicana sp. nov., an Opportunistic Human Pathogen in Africa  

Microsoft Academic Search

A gram-negative bacterium was isolated from a cerebrospinal fluid sample from an HIV-seropositive Rwandan refugee with primary meningoencephalitis. This Marseille-Goma sample B isolate, strain MGBT (T = type strain), was found to exhibit evolutionary homology with Stenotrophomonas maltophilia, as deter- mined by a 16s rRNA gene sequence analysis, and this finding was reflected by similar phenotypic traits. MGBT could, however,

M. DRANCOURT; C. BOLLET; D. RAOULT

68

Phylogenetic Analysis of Stenotrophomonas spp. Isolates Contributes to the Identification of Nosocomial and Community-Acquired Infections  

PubMed Central

Stenotrophomonas ssp. has a wide environmental distribution and is also found as an opportunistic pathogen, causing nosocomial or community-acquired infections. One species, S. maltophilia, presents multidrug resistance and has been associated with serious infections in pediatric and immunocompromised patients. Therefore, it is relevant to conduct resistance profile and phylogenetic studies in clinical isolates for identifying infection origins and isolates with augmented pathogenic potential. Here, multilocus sequence typing was performed for phylogenetic analysis of nosocomial isolates of Stenotrophomonas spp. and, environmental and clinical strains of S. maltophilia. Biochemical and multidrug resistance profiles of nosocomial and clinical strains were determined. The inferred phylogenetic profile showed high clonal variability, what correlates with the adaptability process of Stenotrophomonas to different habitats. Two clinical isolates subgroups of S. maltophilia sharing high phylogenetic homogeneity presented intergroup recombination, thus indicating the high permittivity to horizontal gene transfer, a mechanism involved in the acquisition of antibiotic resistance and expression of virulence factors. For most of the clinical strains, phylogenetic inference was made using only partial ppsA gene sequence. Therefore, the sequencing of just one specific fragment of this gene would allow, in many cases, determining whether the infection with S. maltophilia was nosocomial or community-acquired. PMID:24818127

Cerezer, Vinicius Godoy; Pasternak, Jacyr; Franzolin, Marcia Regina; Moreira-Filho, Carlos Alberto

2014-01-01

69

A novel bacterial isolate Stenotrophomonas maltophilia as living factory for synthesis of gold nanoparticles  

Microsoft Academic Search

BACKGROUND: The synthesis of gold nanoparticles (GNPs) has received considerable attention with their potential applications in various life sciences related applications. Recently, there has been tremendous excitement in the study of nanoparticles synthesis by using some natural biological system, which has led to the development of various biomimetic approaches for the growth of advanced nanomaterials. In the present study, we

Yogesh Nangia; Nishima Wangoo; Nisha Goyal; G Shekhawat; C Raman Suri

2009-01-01

70

Characterization of a novel Stenotrophomonas isolate with high keratinase activity and purification of the enzyme.  

PubMed

A feather-degrading bacterium was isolated from poultry decomposition feathers in China. The strain, named L1, showed significant feather-degrading activity because it grew and reproduced quickly on basal medium containing 10 g/L of native feather as the source of energy, carbon, and nitrogen. According to the phenotypic characteristics and 16S rRNA profile, the isolate belongs to Stenotrophomonas maltophilia. Keratinase activity of the isolate was determined during cultivation on raw feathers at different temperatures and initial pH. Maximum growth and feather-degrading activity of the bacterium were observed at 40 degrees C and initial pH ranging from 7.5 to 8.0. The crude enzyme was purified by ammonium sulphate precipitation, Sephadex G-100 chromatographic and ceramic hydroxyapatite (CHT) chromatographic. Its molecular mass estimated as 35.2 kDa in SDS-PAGE. The enzyme had an optimum activity at the pH was 7.8 and the temperature was 40 degrees C. The keratinase was wholly inhibited by a serine protease inhibitor, PMSF. Its activity was activated or inhibited by different metal ions. The keratinase activity of enzyme from strain L1 functioned on different keratins, such as feather, hair, wool, horn, and so on. PMID:19137342

Cao, Zhang-Jun; Zhang, Qi; Wei, Dong-Kai; Chen, Li; Wang, Jing; Zhang, Xing-Qun; Zhou, Mei-Hua

2009-02-01

71

Genome Sequence of Bacillus licheniformis CGMCC3963, a Stress-Resistant Strain Isolated in a Chinese Traditional Solid-State Liquor-Making Process  

PubMed Central

Bacillus licheniformis CGMCC3963 is an important mao-tai flavor-producing strain. It was isolated from the starter (Daqu) of a Chinese mao-tai-flavor liquor fermentation process with solid-state fermentation. We report its genome of 4,525,096 bp here. Many potential insertion genes that are responsible for the unique properties of B. licheniformis CGMCC3963 in mao-tai-flavor liquor production were identified. PMID:23405325

Wu, Qun; Peng, Suqin; Yu, Yao; Li, Yixue

2013-01-01

72

Co-metabolic transformation of the neonicotinoid insecticide imidacloprid by the new soil isolate Pseudoxanthomonas indica CGMCC 6648.  

PubMed

A new imidacloprid (IMI) degrading bacterium Z-9 (deposited number CGMCC 6648) was isolated and identified as Pseudoxanthomonas indica by 16S rRNA gene analysis. Two metabolites were identified as olefin and 5-hydroxy IMI by liquid chromatography-mass spectrometry and nuclear magnetic resonance analysis. P. indica CGMCC 6648 degraded 70.1% of IMI (1.22 mmol L(-1)) and formed 0.93 mmol L(-1) 5-hydroxy IMI and 0.05 mmol L(-1) olefin IMI in 6 days and in the presence of 100 mmol L(-1) glucose. The half-life of IMI degradation was 3.6 days. P. indica CGMCC 6648 transforms IMI via a co-metabolism mechanism and different carbohydrates have significant effects on 5-hydroxy IMI formation, whereas different organic acids have substantial effects on olefin IMI production. Lactose is the best co-substrate for IMI degradation and 5-hydroxy IMI formation with 0.77 mmol L(-1) degraded and 0.67 mmol L(-1) formed in 48 h, respectively. Pyruvate is the best co-substrate for olefin IMI formation with 0.17 mmol L(-1) produced in 96 h for all carbon sources tested. Pyruvate significantly stimulates the conversion of 5-hydroxy IMI to olefin IMI, whereas glucose slightly inhibits this reaction. P. indica CGMCC 6648 rapidly degrades IMI and forms olefin IMI, which may enhance its potential for biodegradation of IMI and increase its insecticidal activity, which can decrease the IMI dosage required. PMID:25035915

Ma, Yuan; Zhai, Shan; Mao, Shi Yun; Sun, Shi Lei; Wang, Ying; Liu, Zhong Hua; Dai, Yi Jun; Yuan, Sheng

2014-01-01

73

Purification and characterisation of a bifunctional alginate lyase from novel Isoptericola halotolerans CGMCC 5336.  

PubMed

A novel halophilic alginate-degrading microorganism was isolated from rotten seaweed and identified as Isoptericola halotolerans CGMCC5336. The lyase from the strain was purified to homogeneity by combining of ammonium sulfate fractionation and anion-exchange chromatography with a specific activity of 8409.19 U/ml and a recovery of 25.07%. This enzyme was a monomer with a molecular mass of approximately 28 kDa. The optimal temperature and pH were 50 °C and pH 7.0, respectively. The lyase maintained stability at neutral pH (7.0-8.0) and temperatures below 50 °C. Metal ions including Na(+), Mg(2+), Mn(2+), and Ca(2+) notably increased the activity of the enzyme. With sodium alginate as the substrate, the Km and Vmax were 0.26 mg/ml and 1.31 mg/ml min, respectively. The alginate lyase had substrate specificity for polyguluronate and polymannuronate units in alginate molecules, indicating its bifunctionality. These excellent characteristics demonstrated the potential applications in alginate oligosaccharides production with low polymerisation degrees. PMID:24053829

Dou, Wenfang; Wei, Dan; Li, Hui; Li, Heng; Rahman, Muhammad Masfiqur; Shi, Jinsong; Xu, Zhenghong; Ma, Yanhe

2013-11-01

74

Study of the anti-sapstain fungus activity of Bacillus amyloliquefaciens CGMCC 5569 associated with Ginkgo biloba and identification of its active components.  

PubMed

An endophytic bacterium, designated strain Bacillus amyloliquefaciens CGMCC 5569 was isolated from Chinese medicinal Ginkgo biloba collected from Xuzhou, China. Both the filtrate and the ethyl acetate extract of strain CGMCC 5569 showed growth inhibition activity against the sapstain fungi Lasiodiplodia rubropurpurea, L. crassispora, and L. theobromae obviously (>65%) based on the comparison of the length of zones on the petri dish. From the ethyl acetate extract of the filtrate, the antifungal compounds were obtained as a series of lipopeptides, which including series of fengycin, surfactin and bacillomycin. It showed strong growth inhibition activity in vitro against the L. rubropurpurea, L. crassispora and L. theobromae by about 70.22%, 69.53% and 78.76%, respectively. The strong anti-sapstain fungus activity indicated that the endophytic B. amyloliquefaciens CGMCC 5569 and its bioactive components might provide an alternative bio-resource for the bio-control of sapstain. PMID:22520222

Yuan, Bo; Wang, Zhe; Qin, Sheng; Zhao, Gui-Hua; Feng, You-Jian; Wei, Li-Hui; Jiang, Ji-Hong

2012-06-01

75

Degradation Potential of Protocatechuate 3,4-Dioxygenase from Crude Extract of Stenotrophomonas maltophilia Strain KB2 Immobilized in Calcium Alginate Hydrogels and on Glyoxyl Agarose  

PubMed Central

Microbial intradiol dioxygenases have been shown to have a great potential for bioremediation; however, their structure is sensitive to various environmental and chemical agents. Immobilization techniques allow for the improvement of enzyme properties. This is the first report on use of glyoxyl agarose and calcium alginate as matrixes for the immobilization of protocatechuate 3,4-dioxygenase. Multipoint attachment of the enzyme to the carrier caused maintenance of its initial activity during the 21 days. Immobilization of dioxygenase in calcium alginate or on glyoxyl agarose resulted in decrease in the optimum temperature by 5°C and 10°C, respectively. Entrapment of the enzyme in alginate gel shifted its optimum pH towards high-alkaline pH while immobilization of the enzyme on glyoxyl agarose did not influence pH profile of the enzyme. Protocatechuate 3,4-dioygenase immobilized in calcium alginate showed increased activity towards 2,5-dihydroxybenzoate, caffeic acid, 2,3-dihydroxybenzoate, and 3,5-dihydroxybenzoate. Slightly lower activity of the enzyme was observed after its immobilization on glyoxyl agarose. Entrapment of the enzyme in alginate gel protected it against chelators and aliphatic alcohols while its immobilization on glyoxyl agarose enhanced enzyme resistance to inactivation by metal ions. PMID:24693536

Krysiak, Marta

2014-01-01

76

Immunoelectron microscopic demonstration of an esterase on the outer membrane of Xanthomonas maltophilia.  

PubMed Central

Xanthomonas maltophilia (later synonym of Pseudomonas maltophilia), an ubiquitous species, is known to show proteolytic and lipolytic activities. A cell-bound esterase which hydrolyzes beta-naphthyl acetate during growth has been extracted from a strain isolated from soil. Because of its strongly hydrophobic character, the enzyme could be efficiently solubilized only by Triton X-100. This nonionic detergent must be added in polyacrylamide gels to permit migration. Polyclonal rabbit antibodies raised against the Triton-soluble esterase complex were used to localize the enzyme at the ultrastructural level. Electron microscopy of cell sections of this organism and immunogold labeling demonstrated that the enzyme was located on the outer membrane. Such an envelope-bound esterase may produce assimilable substrates for X. maltophilia which can grow in various environments. Images PMID:2495761

Debette, J; Prensier, G

1989-01-01

77

Production of bacterial cellulose by Gluconacetobacter hansenii CGMCC 3917 using only waste beer yeast as nutrient source.  

PubMed

In order to improve the use of waste beer yeast (WBY) for bacterial cellulose production by Gluconacetobacter hansenii CGMCC 3917, a two-step pre-treatment was designed. First WBY was treated by 4 methods: 0.1M NaOH treatment, high speed homogenizer, ultrasonication and microwave treatment followed by hydrolysis (121°C, 20 min) under mild acid condition (pH 2). The optimal pre-treatment conditions were evaluated by the reducing sugar yield after hydrolysis. 15% WBY treated by ultrasonication for 40 min had the highest reducing sugar yield (29.19%), followed by NaOH treatment (28.98%), high speed homogenizer (13.33%) and microwaves (13.01%). Treated WBY hydrolysates were directly supplied as only nutrient source for BC production. A sugar concentration of 3% WBY hydrolysates treated by ultrasonication gave the highest BC yield (7.02 g/L), almost 6 times as that from untreated WBY (1.21 g/L). Furthermore, the properties of the BC were as good as those obtained from the conventional chemical media. PMID:24212131

Lin, Dehui; Lopez-Sanchez, Patricia; Li, Rui; Li, Zhixi

2014-01-01

78

Enhancement of sophorolipid production of Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 by low-energy ion beam implantation.  

PubMed

To meet the increasing demands of sophorolipids as biosurfactants and bioactive compounds, it is necessary to obtain higher and more specific sophorolipid-producing strains. One sophorolipid-producing strain, Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 (Y(2A)), was mutated by low-energy nitrogen ion beam implantation. Eighteen mutants produced 20 % more sophorolipids than the wild strain, and one mutant, N3-18, produced the highest yield of sophorolipids, 104 g/l, in a shaking flask, which increased by 84.71 % than the wild strain, and further elevated to 135 g/l in a 5-l bioreactor. High performance liquid chromatography analysis showed that the composition of every sophorolipid mixture from different strains was similar, while the contents of most components from mutants were higher than that from the wild strain. Two mutants, N1-32 and N3-18, produced more acidic sophorolipid components; three lactonic sophorolipid molecules with good anticancer activities were greatly enhanced in several mutants, especially monoacetylated lactonic sophorolipid with a C18 monounsaturated fatty acid, which were enhanced by 153 and 211 % in strains N1-32 and N3-18. Low-energy nitrogen ion beam implantation was efficient for obtaining a variety of high and specific sophorolipid-producing mutants to be applied in food, cosmetic, environmental, and pharmaceutical sectors. PMID:22562550

Li, Hui; Ma, Xiaojing; Shao, Lingjian; Shen, Jing; Song, Xin

2012-06-01

79

Revealing differences in metabolic flux distributions between a mutant strain and its parent strain Gluconacetobacter xylinus CGMCC 2955.  

PubMed

A better understanding of metabolic fluxes is important for manipulating microbial metabolism toward desired end products, or away from undesirable by-products. A mutant strain, Gluconacetobacter xylinus AX2-16, was obtained by combined chemical mutation of the parent strain (G. xylinus CGMCC 2955) using DEC (diethyl sulfate) and LiCl. The highest bacterial cellulose production for this mutant was obtained at about 11.75 g/L, which was an increase of 62% compared with that by the parent strain. In contrast, gluconic acid (the main byproduct) concentration was only 5.71 g/L for mutant strain, which was 55.7% lower than that of parent strain. Metabolic flux analysis indicated that 40.1% of the carbon source was transformed to bacterial cellulose in mutant strain, compared with 24.2% for parent strain. Only 32.7% and 4.0% of the carbon source were converted into gluconic acid and acetic acid in mutant strain, compared with 58.5% and 9.5% of that in parent strain. In addition, a higher flux of tricarboxylic acid (TCA) cycle was obtained in mutant strain (57.0%) compared with parent strain (17.0%). It was also indicated from the flux analysis that more ATP was produced in mutant strain from pentose phosphate pathway (PPP) and TCA cycle. The enzymatic activity of succinate dehydrogenase (SDH), which is one of the key enzymes in TCA cycle, was 1.65-fold higher in mutant strain than that in parent strain at the end of culture. It was further validated by the measurement of ATPase that 3.53-6.41 fold higher enzymatic activity was obtained from mutant strain compared with parent strain. PMID:24901455

Zhong, Cheng; Li, Fei; Liu, Miao; Yang, Xiao-Ning; Zhu, Hui-Xia; Jia, Yuan-Yuan; Jia, Shi-Ru; Piergiovanni, Luciano

2014-01-01

80

Identification of a cocaine esterase in a strain of Pseudomonas maltophilia.  

PubMed Central

A strain of Pseudomonas maltophilia (termed MB11L) which was capable of using cocaine as its sole carbon and energy source was isolated by selective enrichment. An inducible esterase catalyzing the hydrolysis of cocaine to ecgonine methyl ester and benzoic acid was identified and purified 22-fold. In the presence of the solubilizing agent cholate, cocaine esterase had a native Mr of 110,000 and was shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be a monomer. In the absence of cholate, cocaine esterase had a native Mr of 410,000 and probably existed as a tetramer. The pH optimum of the enzyme was 8.0, and the Km values for cocaine, ethyl benzoate, and ethyl 2-hydroxybenzoate were 0.36, 1.89, and 1.75 mM, respectively. Inhibition studies indicated that the enzyme was a serine esterase, possibly possessing a cation-binding site similar to those of mammalian acetylcholinesterase and the atropine esterase of Pseudomonas putida PMBL-1. The cocaine esterase of P. maltophilia MB11L showed no activity with atropine, despite the structural similarity of cocaine and atropine. PMID:1551831

Britt, A J; Bruce, N C; Lowe, C R

1992-01-01

81

Biodegradation of toluene and xylenes under microaerophilic and denitrifying conditions by Pseudomonas maltophilia  

SciTech Connect

Aerobic biodegradation of aromatic hydrocarbons has been well studied. Under aerobic conditions, aerobes or facultative anaerobes can utilize aromatic hydrocarbons as sole carbon and energy sources by using oxygen as the cosubstrate of oxygenase enzymes for the initial attack of the aromatic ring and as the terminal electron acceptor for aerobic respiration. However, some facultative or obligate anaerobes can degrade these hydrocarbons by using alternate electron acceptors, such as nitrate, sulfate, carbon dioxide, or iron for anaerobic respiration. Among the potential alternate electron acceptors available, nitrate is the most common one used by microorganisms under oxygen-limited conditions. The first objective of this project was to explore hydrocarbon utilization under anoxic or low oxygen conditions. A microorganism that can utilize the petroleum hydrocarbons, toluene and xylene, as sole carbon and energy sources under microaerophilic (2% oxygen) and denitrifying conditions was isolated and characterized. Since oxygen may repress microbial denitrification, it was of interest to monitor the effects of low oxygen levels on aromatic hydrocarbon biodegradation coupled to denitrification. We isolated a Gram-negative rod, Pseudomonas maltophilia from anaerobic sewage digester sludge. The patterns of biodegradations of toluene and two isomers of xylenes, m- and p-xylene, were very similar under either microaerophilic or anaerobic conditions. Nitrate reduction was also observed during time course experiments under aerobic conditions. The final objective was to test the feasibility of an immobilized cell reactor to treat waste streams. Therefore, a bench-scale bioreactor was built to treat a waste stream contaminated with both toluene and nitrate without aeration. The utilization of toluene and nitrate was monitored periodically in a continuous system under anaerobic conditions.

Su, J.J.

1994-01-01

82

Biosynthesis of gold and silver nanoparticles using a novel marine strain of Stenotrophomonas.  

PubMed

The present study aims at exploiting marine microbial diversity for biosynthesis of metal nanoparticles and also investigates role of microbial proteins in the process of bio-mineralization of gold and silver. This is the first report for concurrent production of gold and silver nanoparticles (AuNPs and AgNPs) by extracellular secretion of a novel strain of Stenotrophomonas, isolated from Indian marine origin. This novel strain has faster rate kinetics for AgNPs synthesis than any other organism reported earlier. The nanoparticles were further characterized using UV-vis spectrophotometer, TEM, DLS and EDAX confirming their size ranging from 10-50 nm and 40-60 nm in dimensions for AuNPs and AgNPs, respectively. TEM analysis indicated formation of multi-shaped nanoparticles with heterogeneous size distribution in both the cases. Finally, the SDS-PAGE analysis of extracellular media supernatant suggested a potential involvement of certain low molecular weight secretory proteins in AuNPs and AgNPs biosynthesis. PMID:23791020

Malhotra, Ankit; Dolma, Kunzes; Kaur, Navjot; Rathore, Y S; Ashish; Mayilraj, S; Choudhury, Anirban Roy

2013-08-01

83

Root-microbe systems: the effect and mode of interaction of Stress Protecting Agent (SPA) Stenotrophomonas rhizophila DSM14405T  

PubMed Central

Stenotrophomonas rhizophila has great potential for applications in biotechnology and biological control due to its ability to both promote plant growth and protect roots against biotic and a-biotic stresses, yet little is known about the mode of interactions in the root-environment system. We studied mechanisms associated with osmotic stress using transcriptomic and microscopic approaches. In response to salt or root extracts, the transcriptome of S. rhizophila DSM14405T changed drastically. We found a notably similar response for several functional gene groups responsible for general stress protection, energy production, and cell motility. However, unique changes in the transcriptome were also observed: the negative regulation of flagella-coding genes together with the up-regulation of the genes responsible for biofilm formation and alginate biosynthesis were identified as a single mechanism of S. rhizophila DSM14405T against salt shock. However, production and excretion of glucosylglycerol (GG) were found as a remarkable mechanism for the stress protection of this Stenotrophomonas strain. For S. rhizophila treated with root exudates, the shift from the planktonic lifestyle to a sessile one was measured as expressed in the down-regulation of flagellar-driven motility. These findings fit well with the observed positive regulation of host colonization genes and microscopic images that show different colonization patterns of oilseed rape roots. Spermidine, described as a plant growth regulator, was also newly identified as a protector against stress. Overall, we identified mechanisms of Stenotrophomonas to protect roots against osmotic stress in the environment. In addition to both the changes in life style and energy metabolism, phytohormons, and osmoprotectants were also found to play a key role in stress protection. PMID:23717321

Alavi, Peyman; Starcher, Margaret R.; Zachow, Christin; Muller, Henry; Berg, Gabriele

2013-01-01

84

Simultaneous Cr(VI) reduction and phenol degradation using Stenotrophomonas sp. isolated from tannery effluent contaminated soil.  

PubMed

This study presents simultaneous hexavalent chromium (Cr(VI)) reduction and phenol degradation using Stenotrophomonas sp., isolated from tannery effluent contaminated soil. Phenol was used as the sole carbon and energy source for Cr(VI) reduction. The optimization of different operating parameters was done using Placket-Burman design (PBD) and Box-Behnken design (BBD). The significant operating variables identified by PBD were initial Cr(VI) and phenol concentration, pH, temperature, and reaction time. These variables were optimized by a three-level BBD and the optimum initial Cr(VI) concentration, initial phenol concentration, pH, temperature, and reaction time obtained were 16.59 mg/l, 200.05 mg/l, 7.38, 31.96 °C and 4.07 days, respectively. Under the optimum conditions, 81.27 % Cr(VI) reduction and 100 % phenol degradation were observed experimentally. The results concluded that the Stenotrophomonas sp. could be used to decontaminate the effluents containing Cr(VI) and phenol effectively. PMID:23608988

Gunasundari, Dharmaraj; Muthukumar, Karuppan

2013-09-01

85

Arsenic bioremediation potential of a new arsenite-oxidizing bacterium Stenotrophomonas sp. MM-7 isolated from soil.  

PubMed

A new arsenite-oxidizing bacterium was isolated from a low arsenic-containing (8.8 mg kg(-1)) soil. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the strain was closely related to Stenotrophomonas panacihumi. Batch experiment results showed that the strain completely oxidized 500 ?M of arsenite to arsenate within 12 h of incubation in a minimal salts medium. The optimum initial pH range for arsenite oxidation was 5-7. The strain was found to tolerate as high as 60 mM arsenite in culture media. The arsenite oxidase gene was amplified by PCR with degenerate primers. The deduced amino acid sequence showed the highest identity (69.1 %) with the molybdenum containing large subunit of arsenite oxidase derived from Bosea sp. Furthermore the amino acids involved in binding the substrate arsenite, were conserved with the arsenite oxidases of other arsenite oxidizing bacteria such as Alcaligenes feacalis and Herminnimonas arsenicoxydans. To our knowledge, this study constitutes the first report on arsenite oxidation using Stenotrophomonas sp. and the strain has great potential for application in arsenic remediation of contaminated water. PMID:22760225

Bahar, Md Mezbaul; Megharaj, Mallavarapu; Naidu, Ravi

2012-11-01

86

Degradation of Microcystin-LR and RR by a Stenotrophomonas sp. Strain EMS Isolated from Lake Taihu, China  

PubMed Central

A bacterial strain EMS with the capability of degrading microcystins (MCs) was isolated from Lake Taihu, China. The bacterium was tentatively identified as a Stenotrophomonas sp. The bacterium could completely consume MC-LR and MC-RR within 24 hours at a concentration of 0.7 ?g/mL and 1.7 ?g/mL, respectively. The degradation of MC-LR and MC-RR by EMS occurred preferentially in an alkaline environment. In addition, mlrA gene involved in the degradation of MC-LR and MC-RR was detected in EMS. Due to the limited literature this gene has rare homologues. Sequencing analysis of the translated protein from mlrA suggested that MlrA might be a transmembrane protein, which suggests a possible new protease family having unique function. PMID:20479990

Chen, Jian; Hu, Liang Bin; Zhou, Wei; Yan, Shao Hua; Yang, Jing Dong; Xue, Yan Feng; Shi, Zhi Qi

2010-01-01

87

Feeding strategies for the enhanced production of ?-arbutin in the fed-batch fermentation of Xanthomonas maltophilia BT-112.  

PubMed

To develop a cost-effective method for the enhanced production of ?-arbutin using Xanthomonas maltophilia BT-112 as a biocatalyst, different fed-batch strategies such as constant feed rate fed-batch, constant hydroquinone (HQ) concentration fed-batch, exponential fed-batch and DO-control pulse fed-batch (DPFB) on ?-arbutin production were investigated. The research results indicated that DPFB was an effective method for ?-arbutin production. When fermentation with DO-control pulse feeding strategy to feed HQ and yeast extract was applied, the maximum concentrations of ?-arbutin and cell dry weight were 61.7 and 4.21 g/L, respectively. The ?-arbutin production was 394% higher than that of the control (batch culture) and the molar conversion yield of ?-arbutin reached 94.5% based on the amount of HQ supplied (240 mM). Therefore, the results in this work provide an efficient and easily controlled method for industrial-scale production of ?-arbutin. PMID:23722821

Liu, Chunqiao; Zhang, Peng; Zhang, Shurong; Xu, Tao; Wang, Fang; Deng, Li

2014-02-01

88

Whole-genome sequence assembly of Pediococcus pentosaceus LI05 (CGMCC 7049) from the human gastrointestinal tract and comparative analysis with representative sequences from three food-borne strains  

PubMed Central

Background Strains of Pediococcus pentosaceus from food and the human gastrointestinal tract have been widely identified, and some have been reported to reduce inflammation, encephalopathy, obesity and fatty liver in animals. In this study, we sequenced the whole genome of P. pentosaceus LI05 (CGMCC 7049), which was isolated from the fecal samples of healthy volunteers, and determined its ability to reduce acute liver injury. No other genomic information for gut-borne P. pentosaceus is currently available in the public domain. Results We obtained the draft genome of P. pentosaceus LI05, which was 1,751,578 bp in size and possessed a mean G?+?C content of 37.3%. This genome encoded an abundance of proteins that were protective against acids, bile salts, heat, oxidative stresses, enterocin A, arsenate and universal stresses. Important adhesion proteins were also encoded by the genome. Additionally, P. pentosaceus LI05 genes encoded proteins associated with the biosynthesis of not only three antimicrobials, including prebacteriocin, lysin and colicin V, but also vitamins and functional amino acids, such as riboflavin, folate, biotin, thiamine and gamma-aminobutyrate. A comparison of P. pentosaceus LI05 with all known genomes of food-borne P. pentosaceus strains (ATCC 25745, SL4 and IE-3) revealed that it possessed four novel exopolysaccharide biosynthesis proteins, additional putative environmental stress tolerance proteins and phage-related proteins. Conclusions This work demonstrated the probiotic properties of P. pentosaceus LI05 from the gut and the three other food-borne P. pentosaceus strains through genomic analyses. We have revealed the major genomic differences between these strains, providing a framework for understanding the probiotic effects of strain LI05, which exhibits unique physiological and metabolic properties. PMID:25349631

2014-01-01

89

The plant-associated bacterium Stenotrophomonas rhizophila expresses a new enzyme for the synthesis of the compatible solute glucosylglycerol.  

PubMed

The rhizobacterium Stenotrophomonas rhizophila accumulates the compatible solutes glucosylglycerol (GG) and trehalose under salt stress conditions. The complete gene for the GG synthesis enzyme was cloned and sequenced. This enzyme from S. rhizophila represented a novel fusion protein composed of a putative C-terminal GG-phosphate synthase domain and an N-terminal putative GG-phosphate phosphatase domain, which was named GgpPS. A similar gene was cloned from Pseudomonas sp. strain OA146. The ggpPS gene was induced after a salt shock in S. rhizophila cells. After the salt-loaded cells reached stationary phase, the ggpPS mRNA content returned to the low level characteristic of the control cells, and GG was released into the medium. The complete ggpPS gene and a truncated version devoid of the phosphatase part were obtained as recombinant proteins. Enzyme activity tests revealed the expected abilities of the full-length protein to synthesize GG and the truncated GgpPS to synthesize GG-phosphate. However, dephosphorylation of GG-phosphate was detected only with the complete GgpPS protein. These enzyme activities were confirmed by complementation experiments using defined GG-defective mutants of the cyanobacterium Synechocystis sp. strain PCC 6803. Genes coding for proteins very similar to the newly identified fusion protein GgpPS for GG synthesis in S. rhizophila were found in genome sequences of related bacteria, where these genes are often linked to a gene coding for a transporter of the Mfs superfamily. PMID:18586931

Hagemann, Martin; Ribbeck-Busch, Kathrin; Klähn, Stephan; Hasse, Dirk; Steinbruch, Robert; Berg, Gabriele

2008-09-01

90

The Plant-Associated Bacterium Stenotrophomonas rhizophila Expresses a New Enzyme for the Synthesis of the Compatible Solute Glucosylglycerol?  

PubMed Central

The rhizobacterium Stenotrophomonas rhizophila accumulates the compatible solutes glucosylglycerol (GG) and trehalose under salt stress conditions. The complete gene for the GG synthesis enzyme was cloned and sequenced. This enzyme from S. rhizophila represented a novel fusion protein composed of a putative C-terminal GG-phosphate synthase domain and an N-terminal putative GG-phosphate phosphatase domain, which was named GgpPS. A similar gene was cloned from Pseudomonas sp. strain OA146. The ggpPS gene was induced after a salt shock in S. rhizophila cells. After the salt-loaded cells reached stationary phase, the ggpPS mRNA content returned to the low level characteristic of the control cells, and GG was released into the medium. The complete ggpPS gene and a truncated version devoid of the phosphatase part were obtained as recombinant proteins. Enzyme activity tests revealed the expected abilities of the full-length protein to synthesize GG and the truncated GgpPS to synthesize GG-phosphate. However, dephosphorylation of GG-phosphate was detected only with the complete GgpPS protein. These enzyme activities were confirmed by complementation experiments using defined GG-defective mutants of the cyanobacterium Synechocystis sp. strain PCC 6803. Genes coding for proteins very similar to the newly identified fusion protein GgpPS for GG synthesis in S. rhizophila were found in genome sequences of related bacteria, where these genes are often linked to a gene coding for a transporter of the Mfs superfamily. PMID:18586931

Hagemann, Martin; Ribbeck-Busch, Kathrin; Klahn, Stephan; Hasse, Dirk; Steinbruch, Robert; Berg, Gabriele

2008-01-01

91

Characterization of N2O-producing Xanthomonas-like isolates from biofilters as Stenotrophomonas nitritireducens sp. nov., Luteimonas mephitis gen. nov., sp. nov. and Pseudoxanthomonas broegbernensis gen. nov., sp. nov.  

PubMed

A group of yellow-pigmented isolates from ammonia-supplied biofilters showed an unusual denitrification reaction. All strains reduced nitrite but not nitrate without production of nitrogen (N2). The only product found was nitrous oxide (N2O). The strains were divided into two clusters and one separate strain by their fatty acid profiles, which were similar to the fatty acid profiles of the genera Xanthomonas and Stenotrophomonas. Analyses of the 165 rDNA sequences showed that these clusters and the separate strain form three independent lines within the Xanthomonas branch of the Proteobacteria. The evolutionary distances of the isolates to members of the related genera Xanthomonas, Stenotrophomonas and Xylella calculated by the 16S rDNA sequences led to the proposal of two new genera and three new species, Stenotrophomonas nitritireducens sp. nov., Luteimonas mephitis gen. nov., sp. nov. and Pseudoxanthomonas broegbernensis gen. nov., sp. nov. The type strains are Stenotrophomonas nitritireducens L2T (= DSM 12575T), Luteimonas mephitis B1953/27.1T (= DSM 12574T) and Pseudoxanthomonas broegbernensis B1616/1T (= DSM 12573T). PMID:10826814

Finkmann, W; Altendorf, K; Stackebrandt, E; Lipski, A

2000-01-01

92

Prevenzione della infezione incrociata nella Fibrosi Cistica: come delle iniziative relativamente semplici hanno migliorato la prognosi in soggetti affetti da fibrosi cistica in Danimarca  

Microsoft Academic Search

La maggioranza dei pazienti adulti con fibrosi cistica (FC) contraggono infezione batterica polmonare cronica. I più comuni agenti patogeni nella FC nel mondo sono i seguenti: • Pseudomonas aeruginosa (P. aeruginosa), seguito da • Staffilococco aureo (S. aureus), • Complesso Burkholderia cepacia (B. cepacia), • Achromobacter xylosoxidans (A. xylosoxidans), • Stenotrophomonas maltophilia (S. maltophilia) • Micobatteri non tubercolosi (MNT). La

Claus Moser; Niels Høiby

93

Pseudoxanthomonas sacheonensis sp. nov., isolated from BTEX-contaminated soil in Korea, transfer of Stenotrophomonas dokdonensis Yoon et al. 2006 to the genus Pseudoxanthomonas as Pseudoxanthomonas dokdonensis comb. nov. and emended description of the genus Pseudoxanthomonas.  

PubMed

A Gram-negative, strictly aerobic, rod-shaped bacterium, designated strain BD-c54(T), was isolated from BTEX (benzene, toluene, ethylbenzene and xylenes)-contaminated soil in Sacheon, Korea. Growth of strain BD-c54(T) was observed at 15-35 degrees C (optimum 25-30 degrees C) and pH 6.0-9.5 (optimum pH 7.0-8.0). The predominant fatty acids were iso-C(15:0), iso-C(17:1)omega9c, iso-C(11:0) 3-OH, iso-C(16:0), iso-C(11:0) and iso-C(17:0). The strain contained large amounts of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol and a small amount of an unknown amino-group-containing polar lipid as polar lipids. The major quinone was ubiquinone-8 (Q-8) and the G+C content of the genomic DNA was 67.5 mol%. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain BD-c54(T) formed a tight phylogenetic lineage with Pseudoxanthomonas yeongjuensis GR12-1(T) within the genus Pseudoxanthomonas and was most closely related to P. yeongjuensis GR12-1(T) and [Stenotrophomonas] dokdonensis DS-16(T), with 98.3 and 96.6% 16S rRNA gene sequence similarity, respectively. The DNA-DNA relatedness between strain BD-c54(T) and P. yeongjuensis GR12-1(T) was 24.5%. On the basis of chemotaxonomic data and molecular properties, strain BD-c54(T) represents a novel species within the genus Pseudoxanthomonas, for which the name Pseudoxanthomonas sacheonensis sp. nov. is proposed. The type strain is BD-c54(T) (=KCTC 22080(T) =DSM 19373(T)). In addition, the transfer of Stenotrophomonas dokdonensis to Pseudoxanthomonas as Pseudoxanthomonas dokdonensis comb. nov. and an emended description of the genus Pseudoxanthomonas are proposed. PMID:18768635

Lee, Dae Sung; Ryu, Seung Hyun; Hwang, Hyun Wook; Kim, Young-Ju; Park, Minjeong; Lee, Jung Ro; Lee, Sang-Suk; Jeon, Che Ok

2008-09-01

94

Effect of Eucalyptus Essential Oil on Respiratory Bacteria and Viruses  

Microsoft Academic Search

The activity of Eucalyptus globulus essential oil was determined for 120 isolates of Streptococcus\\u000a pyogenes, 20 isolates of S. pneumoniae, 40 isolates of S. agalactiae, 20 isolates of Staphylococcus aureus, 40 isolates of Haemophilus influenzae, 30 isolates of H. parainfluenzae, 10 isolates of Klebsiella pneumoniae, 10 isolates of Stenotrophomonas maltophilia and two viruses, a strain of adenovirus and a strain

Claudio Cermelli; Anna Fabio; Giuliana Fabio; Paola Quaglio

2008-01-01

95

First reported infections caused by three newly described genera in the family Xanthomonadaceae.  

PubMed

Members of the family of Xanthomonadaceae are typically characterized as environmental organisms. With the exception of Stenotrophomonas maltophilia, these organisms are infrequently implicated as human pathogens. We describe three cases of central venous catheter-associated bloodstream infections caused by Dokdonella koreensis, Aquimonas voraii, and a Luteibacter sp., all newly named genera within the family Xanthomonadaceae. The three patients all had histories of underlying hematological disorders, presented with fever, and recovered fully following treatment. These isolates required 16S rRNA gene sequencing for identification and, unlike S. maltophilia, demonstrated susceptibility to most antibiotics tested. This report represents the first description of human infections caused by these organisms. PMID:17122001

LaSala, P Rocco; Segal, Jonathan; Han, Faye S; Tarrand, Jeffrey J; Han, Xiang Y

2007-02-01

96

First Reported Infections Caused by Three Newly Described Genera in the Family Xanthomonadaceae?  

PubMed Central

Members of the family of Xanthomonadaceae are typically characterized as environmental organisms. With the exception of Stenotrophomonas maltophilia, these organisms are infrequently implicated as human pathogens. We describe three cases of central venous catheter-associated bloodstream infections caused by Dokdonella koreensis, Aquimonas voraii, and a Luteibacter sp., all newly named genera within the family Xanthomonadaceae. The three patients all had histories of underlying hematological disorders, presented with fever, and recovered fully following treatment. These isolates required 16S rRNA gene sequencing for identification and, unlike S. maltophilia, demonstrated susceptibility to most antibiotics tested. This report represents the first description of human infections caused by these organisms. PMID:17122001

LaSala, P. Rocco; Segal, Jonathan; Han, Faye S.; Tarrand, Jeffrey J.; Han, Xiang Y.

2007-01-01

97

Relationships between antimicrobial use and antimicrobial resistance in Gram-negative bacteria causing nosocomial infections from 1991–2003 at a university hospital in Taiwan  

Microsoft Academic Search

This study was conducted to evaluate the relationship between antimicrobial resistance and antimicrobial use in a university hospital in Taiwan. Disk susceptibility data of Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Serratia marcescens, Proteus spp., Pseudomonas aeruginosa, Acinetobacter spp., Stenotrophomonas maltophilia and other non-fermentative Gram-negative bacilli causing nosocomial infections were evaluated. Data on annual patient-days and annual consumption (defined daily dose

Po-Ren Hsueh; Wen-Hwei Chen; Kwen-Tay Luh

2005-01-01

98

Identification of a Novel ?-Lactamase Produced by Xanthomonas campestris, a Phytopathogenic Bacterium  

PubMed Central

The Xanthomonas campestris pv. campestris 11 chromosome encodes a periplasmic ?-lactamase of 30 kDa. Gene replacement and complementation confirmed the presence of this enzyme. Its deduced amino acid sequence shows identity and conserved domains between it and Stenotrophomonas maltophilia L2 and other Ambler class A/Bush group 2 ?-lactamases. Southern hybridization detected a single homologous fragment in each of 12 other Xanthomonas strains, indicating that the presence of a ?-lactamase gene is common among xanthomonads. PMID:10390247

Weng, Shu-Fen; Chen, Chun-Yi; Lee, Yeong-Sheng; Lin, Juey-Wen; Tseng, Yi-Hsiung

1999-01-01

99

Isolation of bacteria able to grow on both polyethylene glycol (PEG) and polypropylene glycol (PPG) and their PEG\\/PPG dehydrogenases  

Microsoft Academic Search

Two bacterial consortia growing on a random copolymer of ethylene glycol and propylene glycol units were obtained by enrichment\\u000a cultures from various microbial samples. Six major strains included in both consortia were purified and identified as Sphingomonads,\\u000a Pseudomonas sp. and Stenotrophomonas maltophilia. Three of them (Sphingobium sp. strain EK-1, Sphingopyxis macrogoltabida strain EY-1, and Pseudomonas sp. strain PE-2) utilized both

Xiaoping Hu; Akira Fukutani; Xin Liu; Kazuhide Kimbara; Fusako Kawai

2007-01-01

100

Effect of uracil on pullulan production by Aureobasidium pullulans CGMCC1234.  

PubMed

Effect of uracil on the pullulan production, biomass and uridine phosphorylase (UPase) activity was studied in this research. Uracil was found to enhance pullulan accumulation and the addition time of uracil was crucial to pullulan production. Pullulan yield of 49.07 g/L was achieved by adding 5mM uracil at 48 h, by comparison to 37.72 g/L obtained with the control. UPase activity could not be detected at early growth stage of Aureobasidium pullulans, but stimulated by added uracil at logarithmic phase and stationary phase. The time course study on the fermentation of pullulan demonstrates that pullulan production was not closely associated with biomass accumulation. Results indicate that the increased pullulan yield brought by uracil was correlated with UPase activity. PMID:24299794

Sheng, Long; Zhu, Guilan; Tong, Qunyi

2014-01-30

101

Gut-associated bacteria throughout the life cycle of the bark beetle Dendroctonus rhizophagus Thomas and Bright (Curculionidae: Scolytinae) and their cellulolytic activities.  

PubMed

Dendroctonus rhizophagus Thomas and Bright (Curculionidae: Scolytinae) is an endemic economically important insect of the Sierra Madre Occidental in Mexico. This bark beetle has an atypical behavior within the genus because just one beetle couple colonizes and kills seedlings and young trees of 11 pine species. In this work, the bacteria associated with the Dendroctonus rhizophagus gut were analyzed by culture-dependent and culture-independent methods. Analysis of 16S rRNA sequences amplified directly from isolates of gut bacteria suggests that the bacterial community associated with Dendroctonus rhizophagus, like that of other Dendroctonus spp. and Ips pini, is limited in number. Nine bacterial genera of ?-Proteobacteria and Actinobacteria classes were detected in the gut of Dendroctonus rhizophagus. Stenotrophomonas and Rahnella genera were the most frequently found bacteria from Dendroctonus rhizophagus gut throughout their life cycle. Stenotrophomonas maltophilia, Ponticoccus gilvus, and Kocuria marina showed cellulolytic activity in vitro. Stenotrophomonas maltophilia, Rahnella aquatilis, Raoultella terrigena, Ponticoccus gilvus, and Kocuria marina associated with larvae or adults of Dendroctonus rhizophagus could be implicated in nitrogen fixation and cellulose breakdown, important roles associated to insect development and fitness, especially under the particularly difficult life conditions of this beetle. PMID:22234511

Morales-Jiménez, Jesús; Zúñiga, Gerardo; Ramírez-Saad, Hugo C; Hernández-Rodríguez, César

2012-07-01

102

Identification and discrimination of bacteria using Fourier transform infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Bacterial spectra were obtained in the wavenumber range of 4000-600 cm-1 using FTIR spectroscopy. FTIR spectral patterns were analyzed and matched with 16S-rRNA signatures of bacterial strains OS1 and OS2, isolated from oil sludge. Specific spectral bands obtained from OS1 (FJ226761), reference strain Bacillus flexus (ATCC 49095), OS2 (FJ215874) and reference strain Stenotrophomonas maltophilia (ATCC 19861) respectively, suggested that OS1 and ATCC 49095 were closely related whereas OS2 was different. The bands probably represent groups of proteins and lipids of specific bacteria. Separate peaks found in B. flexus were similar to those of OS1. The S. maltophilia (ATCC 19861) and OS2 exhibited a similar peak at 3272 cm-1. Amide bands (I, II and III) exhibited that OS1 and B. flexus were closely related, but were different from OS2. In the fingerprint region, peak at 1096 cm-1 and 1360 cm-1 exhibited the specific fingerprints of OS2 and reference strain S. maltophilia (ATCC 19861), respectively. The specific fingerprint signature was found at 1339 cm-1 for OS1 and at 1382 cm-1 for B. flexus ATCC 49095, allowing these two strains of B. flexus to be differentiated. This spectral signature originated from phospholipid and RNA components of the cell. Principle components analysis (PCA) of spectral regions exhibited with distinct sample clusters between Bacillus flexus (ATCC 49095), S. maltophilia (ATCC 19861), OS1 and OS2 in amide and fingerprint region.

Maity, Jyoti Prakash; Kar, Sandeep; Lin, Chao-Ming; Chen, Chen-Yen; Chang, Young-Fo; Jean, Jiin-Shuh; Kulp, Thomas R.

2013-12-01

103

Prevention of biofilm colonization by Gram-negative bacteria on minocycline-rifampin-impregnated catheters sequentially coated with chlorhexidine.  

PubMed

Resistant Gram-negative bacteria are increasing central-line-associated bloodstream infection threats. To better combat this, chlorhexidine (CHX) was added to minocycline-rifampin (M/R) catheters. The in vitro antimicrobial activity of CHX-M/R catheters against multidrug resistant, Gram-negative Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia was tested. M/R and CHX-silver sulfadiazine (CHX/SS) catheters were used as comparators. The novel CHX-M/R catheters were significantly more effective (P < 0.0001) than CHX/SS or M/R catheters in preventing biofilm colonization and showed better antimicrobial durability. PMID:24165191

Jamal, Mohamed A; Rosenblatt, Joel S; Hachem, Ray Y; Ying, Jiang; Pravinkumar, Egbert; Nates, Joseph L; Chaftari, Anne-Marie P; Raad, Issam I

2014-01-01

104

Synthesis, in vitro antimicrobial and cytotoxic activities of novel pyrimidine-benzimidazol combinations.  

PubMed

A series of novel 4-substituted-2-{[(1H-benzo[d]imidazol-2-yl)methyl] thio}-6-methylpyrimidine derivatives were designed, synthesized and evaluated for their cytotoxic activities against four human cancer cell lines and inhibitory activities against five type culture strains in vitro. Some of synthetic pyrimidine-benzimidazol combinations showed good inhibitory activities against Stenotrophomonas maltophilia, especially compounds 7b and 7c. Compounds 7a and 7d exhibited enhanced activities against MGC-803 in vitro, when compared to 5-Fu. PMID:24798098

Chen, Peng-Ju; Yang, Ang; Gu, Yi-Fei; Zhang, Xiao-Song; Shao, Kun-Peng; Xue, Deng-Qi; He, Peng; Jiang, Teng-Fei; Zhang, Qiu-Rong; Liu, Hong-Min

2014-06-15

105

Dictyostelium transcriptional responses to Pseudomonas aeruginosa: common and specific effects from PAO1 and PA14 strains  

E-print Network

shown the utility of this model system of infection to analyze the virulence of other opportunistic pathogens like Stenotrophomonas maltophilia [7]. It has been also demonstrated the validity of D. discoi- deum as a model of infection by intracellular... 0190752 diaminopimelate epimerase 1,08 0,02 -1,06 DDB0204319 Hydroxymethyltransferase 0,63 0,43 -0,20 DDB0168738 putative arginine deiminase -0,62 -0,78 -0,16 DDB0205389 acly, ATP citrate lyase 0,89 0,75 -0,15 DDB0169357 methylenetetrahydrofolate...

Carilla-Latorre, Sergio; Calvo-Garrido, Javier; Bloomfield, Gareth; Skelton, Jason; Kay, Robert R; Ivens, Alasdair; Martinez, Jose L; Escalante, Ricardo

2008-06-30

106

Degradation of multiwall carbon nanotubes by bacteria.  

PubMed

Understanding the environmental transformation of multiwall carbon nanotubes (MWCNTs) is important to their life cycle assessment and potential environmental impacts. We report that a bacterial community is capable of degrading (14)C-labeled MWCNTs into (14)CO2 in the presence of an external carbon source via co-metabolism. Multiple intermediate products were detected, and genotypic characterization revealed three possible microbial degraders: Burkholderia kururiensis, Delftia acidovorans, and Stenotrophomonas maltophilia. This result suggests that microbe/MWCNTs interaction may impact the long-term fate of MWCNTs. PMID:23859846

Zhang, Liwen; Petersen, Elijah J; Habteselassie, Mussie Y; Mao, Liang; Huang, Qingguo

2013-10-01

107

Gram-negative bacteria from the camel tick Hyalomma dromedarii (Ixodidae) and the chicken tick Argas persicus (Argasidae) and their antibiotic sensitivities.  

PubMed

A total of nine species of gram-negative bacteria were isolated from organs and haemolymph of the hard tick Hyalomma (Hyalomma) dromedarii and the soft tick Argas (Persicargas) persicus. Four species namely Serratia liquefaciens, Stenotrophomonas maltophilia, Klebsiella ornithinolytica and Aeromonas hydrophila were isolated from H. dromedarii and five species namely Rahnella aquatilis, Pseudomonas fluorescens, Enterobacter cloacae, Chryseomonas luteola and Chryseobacterium meningosepticum were isolated from A. persicus. Isolated bacteria were identified using the analytical profile index 20E. Disk diffusion test was carried out on all isolated bacteria to determine antibiotic sensitivity of chloramphenicol, amoxillin/clavulanic acid, neomycin, streptomycin, triplesulphur tetracycline and nitrofurantion. The results were discussed. PMID:15880998

Montasser, Ashraf A

2005-04-01

108

Antibiotic-resistant gram-negative bacterial infections in patients with cancer.  

PubMed

Patients with cancer are at high risk for infections caused by antibiotic resistant gram-negative bacteria. In this review, we summarize trends among the major pathogens and clinical syndromes associated with antibiotic resistant gram-negative bacterial infection in patients with malignancy, with special attention to carbapenem and expanded-spectrum ?-lactam resistance in Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia-all major threats to our cancer patients. Optimal therapy for these antibiotic-resistant pathogens still remains to be determined. PMID:25352627

Perez, Federico; Adachi, Javier; Bonomo, Robert A

2014-11-15

109

Isolation and characterization of alkane degrading bacteria from petroleum reservoir waste water in Iran (Kerman and Tehran provenances).  

PubMed

Petroleum products spill and leakage have become two major environmental challenges in Iran. Sampling was performed in the petroleum reservoir waste water of Tehran and Kerman Provinces of Iran. Alkane degrading bacteria were isolated by enrichment in a Bushnel-Hass medium, with hexadecane as sole source of carbon and energy. The isolated strains were identified by amplification of 16S rDNA gene and sequencing. Specific primers were used for identification of alkane hydroxylase gene. Fifteen alkane degrading bacteria were isolated and 8 strains were selected as powerful degradative bacteria. These 8 strains relate to Rhodococcus jostii, Stenotrophomonas maltophilia, Achromobacter piechaudii, Tsukamurella tyrosinosolvens, Pseudomonas fluorescens, Rhodococcus erythropolis, Stenotrophomonas maltophilia, Pseudomonas aeruginosa genera. The optimum concentration of hexadecane that allowed high growth was 2.5%. Gas chromatography results show that all strains can degrade approximately half of hexadecane in one week of incubation. All of the strains have alkane hydroxylase gene which are important for biodegradation. As a result, this study indicates that there is a high diversity of degradative bacteria in petroleum reservoir waste water in Iran. PMID:23790464

Hassanshahian, Mehdi; Ahmadinejad, Mohammad; Tebyanian, Hamid; Kariminik, Ashraf

2013-08-15

110

Non-fermentative gram-negative bacteria in hospital tap water and water used for haemodialysis and bronchoscope flushing: prevalence and distribution of antibiotic resistant strains.  

PubMed

This study provides a detailed description of the distribution of non-fermentative gram-negative bacteria (NFGNB) collected in water sources (tap water and water used for haemodialysis and bronchoscope flushing) from different wards of a tertiary care hospital. The aim is to identify risk practices for patients or to alert clinicians to the possible contamination of environment and medical devices. The resistance profile of NFGNB environmental isolates has shown that more than half (55.56%) of the strains isolated were resistant to one or more antibiotics tested in different antimicrobial categories. In particular, 38.89% of these strains were multidrug resistant (MDR) and 16.67% were extensively drug resistant (XDR). The most prevalent bacterial species recovered in water samples were Pseudomonas aeruginosa, Pseudomonas fluorescens, Ralstonia pickettii and Stenotrophomonas maltophilia. Analysis of antibiotic resistance rates has shown remarkable differences between Pseudomonadaceae (P. aeruginosa and P. fluorescens) and emerging pathogens, such as S. maltophilia and R. pickettii. Multidrug resistance can be relatively common among nosocomial isolates of P. aeruginosa, which represent the large majority of clinical isolates; moreover, our findings highlight that the emergent antibiotic resistant opportunistic pathogens, such as R. pickettii and S. maltophilia, isolated from hospital environments could be potentially more dangerous than other more known waterborne pathogens, if not subjected to surveillance to direct the decontamination procedures. PMID:25173861

Vincenti, Sara; Quaranta, Gianluigi; De Meo, Concetta; Bruno, Stefania; Ficarra, Maria Giovanna; Carovillano, Serena; Ricciardi, Walter; Laurenti, Patrizia

2014-11-15

111

An evaluation of microbial and chemical contamination sources related to the deterioration of tap water quality in the household water supply system.  

PubMed

The predominant microorganisms in samples taken from shower heads in residences in the Korean city "N" were Stenotrophomonas maltophilia, Sphingomonas paucimobilis, Acidovorax temperans, and Microbacterium lacticum. Legionella was not detected in this case. The volatile organic compounds (VOCs) vinylacetate, NN-DMA, cis-1,2-dichloroethylene, epichlorohydrin, and styrene were measured in five types of plastic pipes: PVC, PB, PP, PE, and cPVC. The rate of multiplication of the heterotrophic plate count (HPC) attached on the copper pipe in contact with hot tap water was higher than the rate for the copper pipe in contact with cold tap water. Biofilm accumulation on stainless steel pipes with added acetate (3 mg/L) was 2.56 times higher than the non-supplemented condition. Therefore, the growth of HPC in the pipe system was affected by the type and availability of nutrients and depended on variables such as heating during the hot water supply. PMID:24018837

Lee, Yoonjin

2013-09-01

112

Evaluation of the Colorimetric VITEK 2 Card for Identification of Gram-Negative Nonfermentative Rods: Comparison to 16S rRNA Gene Sequencing?  

PubMed Central

Ninety strains of a collection of well-identified clinical isolates of gram-negative nonfermentative rods collected over a period of 5 years were evaluated using the new colorimetric VITEK 2 card. The VITEK 2 colorimetric system identified 53 (59%) of the isolates to the species level and 9 (10%) to the genus level; 28 (31%) isolates were misidentified. An algorithm combining the colorimetric VITEK 2 card and 16S rRNA gene sequencing for adequate identification of gram-negative nonfermentative rods was developed. According to this algorithm, any identification by the colorimetric VITEK 2 card other than Achromobacter xylosoxidans, Acinetobacter sp., Burkholderia cepacia complex, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia should be subjected to 16S rRNA gene sequencing when accurate identification of nonfermentative rods is of concern. PMID:17507509

Zbinden, A.; Bottger, E. C.; Bosshard, P. P.; Zbinden, R.

2007-01-01

113

Antimicrobial activity and clinical effectiveness of sisomicin: an evaluation of the literature (1995-2011).  

PubMed

The authors sought to evaluate whether sisomicin has a place in the current therapeutic armamentarium. PubMed and Scopus databases were systematically searched. Ten cohort studies and 11 case reports and case series were included evaluating, in total, 383 Gram-positive and 83 Gram-negative isolates. Sisomicin was active in vitro against 41% of Enterococcus spp., 97% of Staphylococcus spp. and was the most active in vitro (74%) aminoglycoside against Stenotrophomonas maltophilia isolates in one study. Regarding clinical effectiveness, sisomicin topical cream was effective in all 290 patients with pyoderma in one study, while the intravenous formulation of sisomicin was effective as prophylaxis for the development of postoperative pneumonia in 91% of lung surgery patients in another. In conclusion, sisomicin may be useful against certain pathogens; however, clinical data are scarce. Further studies are needed and may shed additional light in this area. PMID:23566151

Tansarli, Giannoula S; Rafailidis, Petros I; Papazoglou, Anthia A; Falagas, Matthew E

2013-04-01

114

Diversity of auxin-producing bacteria associated to Pseudomonas savastanoi -induced olive knots.  

PubMed

Forty three strains were isolated from knots induced by Pseudomonas savastanoi in different olive cultivars. All the selected bacteria were shown to produce variable amounts of the plant growth hormone indole-3-acetic acid (IAA). Amplification of the intergenic transcribed spacers (ITS) between 16S and 23S rDNA genes, allowed the clustering of the isolates into seven distinct groups. All isolates from ITS group 1 were positive to the Pseudomonas savastanoi pv. savastanoi specific iaa L gene as shown by PCR. Partial sequencing of 16S rDNA gene confirmed the identity of these isolates to Pseudomonas savastanoi strains and allowed to tentatively assign the other isolates from the remaining ITS groups to Pantoea oleae/agglomerans, Burkholderia cepacia, Pseudomonas putida, Stenotrophomonas maltophilia and Hafnia alvei. Identification of endophytic knot-derived isolates revealed association of various saprophytic and putative human pathogenic bacteria with P. savastanoi pv. savastanoi in knot environment of olive infected trees. PMID:18759227

Ouzari, Hadda; Khsairi, Amel; Raddadi, Noura; Jaoua, Leila; Hassen, Abdennaceur; Zarrouk, Mokhtar; Daffonchio, Daniele; Boudabous, Abdellatif

2008-10-01

115

Capillary isoelectric focusing and fluorometric detection of proteins and microorganisms dynamically modified by poly(ethylene glycol) pyrenebutanoate.  

PubMed

The nonionogenic pyrene-based tenside, poly(ethylene glycol) pyrenebutanoate, was prepared and applied in capillary isoelectric focusing with fluorometric detection. This dye was used here as a buffer additive in capillary isoelectric focusing for a dynamic modification of the sample of proteins and microorganisms. The values of the isoelectric points of the labeled bioanalytes were calculated with use of the fluorescent pI markers and were found comparable with pI of the native compounds. The mixed cultures of proteins and microorganisms, Escherichia coli CCM 3954, Staphylococcus epidermidis CCM 4418, Proteus vulgaris, Enterococcus faecalis CCM 4224, and Stenotrophomonas maltophilia, the strains of the yeast cells, Candida albicans CCM 8180, Candida krusei, Candida parapsilosis, Candida glabrata, Candida tropicalis, and Saccharomyces cerevisiae were reproducibly focused and separated by the suggested technique. Using UV excitation for the on-column fluorometric detection, the minimum detectable amount was down to 10 cells injected on the separation capillary. PMID:17165837

Horka, Marie; Ruzicka, Filip; Horký, Jaroslav; Holá, Veronika; Slais, Karel

2006-12-15

116

Dynamics of Seed-Borne Rice Endophytes on Early Plant Growth Stages  

PubMed Central

Bacterial endophytes are ubiquitous to virtually all terrestrial plants. With the increasing appreciation of studies that unravel the mutualistic interactions between plant and microbes, we increasingly value the beneficial functions of endophytes that improve plant growth and development. However, still little is known on the source of established endophytes as well as on how plants select specific microbial communities to establish associations. Here, we used cultivation-dependent and -independent approaches to assess the endophytic bacterrial community of surface-sterilized rice seeds, encompassing two consecutive rice generations. We isolated members of nine bacterial genera. In particular, organisms affiliated with Stenotrophomonas maltophilia and Ochrobactrum spp. were isolated from both seed generations. PCR-based denaturing gradient gel electrophoresis (PCR-DGGE) of seed-extracted DNA revealed that approximately 45% of the bacterial community from the first seed generation was found in the second generation as well. In addition, we set up a greenhouse experiment to investigate abiotic and biotic factors influencing the endophytic bacterial community structure. PCR-DGGE profiles performed with DNA extracted from different plant parts showed that soil type is a major effector of the bacterial endophytes. Rice plants cultivated in neutral-pH soil favoured the growth of seed-borne Pseudomonas oryzihabitans and Rhizobium radiobacter, whereas Enterobacter-like and Dyella ginsengisoli were dominant in plants cultivated in low-pH soil. The seed-borne Stenotrophomonas maltophilia was the only conspicuous bacterial endophyte found in plants cultivated in both soils. Several members of the endophytic community originating from seeds were observed in the rhizosphere and surrounding soils. Their impact on the soil community is further discussed. PMID:22363438

Hardoim, Pablo R.; Hardoim, Cristiane C. P.; van Overbeek, Leonard S.; van Elsas, Jan Dirk

2012-01-01

117

Microbial contamination of suction tubes attached to suction instruments and preventive methods.  

PubMed

We investigated the microbial contamination of suction tubes attached to wall-type suction instruments. Microbial contamination of suction tubes used for endoscopy or sputum suction in hospital wards was examined before and after their disinfection. In addition, disinfection and washing methods for suction tubes were evaluated. Suction tubes (n=33) before disinfection were contaminated with 10(2)-10(8) colony-forming units (cfu)/tube. The main contaminants were Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia. The suction tubes were disinfected with sodium hypochlorite (n=11) or hot water (n=11), or by an automatic tube cleaner (n=11). After 2-h immersion in 0.1% (1,000 ppm) sodium hypochlorite, 10(3)-10(7) cfu/tube of bacteria were detected in all 11 tubes examined. After washing in hot running water (65 degrees C), 10(3)-10(7) cfu/tube were detected in 3 of the 11 examined tubes. The bacteria detected in the suction tubes after disinfection with sodium hypochlorite or hot water were P. aeruginosa, A. baumannii, and S. maltophilia. On the other hand, after washing with warm water (40 degrees C) using the automatic tube cleaner, contamination was found to be <20 cfu/tube (lower detection limit, 20 cfu/tube) in all 11 tubes examined. These results suggest the usefulness of washing with automatic tube cleaners. PMID:20332576

Yorioka, Katsuhiro; Oie, Shigeharu; Kamiya, Akira

2010-03-01

118

Degradation and mineralization of high-molecular-weight polycyclic aromatic hydrocarbons by defined fungal-bacterial cocultures  

SciTech Connect

This study investigated the biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) in liquid media and soil by bacteria (Stenotrophomonas maltophilia VUN 10,010 and bacterial consortium VUN 10,009) and a fungus (Penicillium janthinellum VUO 10,201) that were isolated from separate creosote- and manufactured-gas plant-contaminated soils. The bacteria could use pyrene as their sole carbon and energy source in a basal salts medium (BSM) and mineralized significant amounts of benzo[a]pyrene cometabolically when pyrene was also present in BSM. P. janthinellum VUO 10,201 could not utilize any high-molecular-weight PAH as sole carbon and energy source but could partially degrade these if cultured in a nutrient broth. Although small amounts of chrysene, benz[a]pyrene, and dibenz[a,h]anthracene were degraded by axenic cultures of these isolates in BSM containing a single PAH, such conditions did not support significant microbial growth or PAH mineralization. However, significant degradation of, and microbial growth on, pyrene, chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene, each as a single PAH in BSM, occurred when P. janthinellum VUO 10,201 and either bacterial consortium VUN 10,009 or S. maltophilia VUN 10,010 were combined in the one culture, i.e., fungal-bacterial cocultures: 25% of the benzo[a]pyrene was mineralized to CO{sub 2} by these cocultures over 49 days, accompanied by transient accumulation and disappearance of intermediates detected by high-pressure liquid chromatography. Inoculation of fungal-bacterial cocultures into PAH-contaminated soil resulted in significantly improved degradation of high-molecular-weight PAHs, benzo[a]pyrene mineralization, and reduction in the mutagenicity of organic soil extracts, compared with the indigenous microbes and soil amended with only axenic inocula.

Boonchan, S.; Britz, M.L.; Stanley, G.A.

2000-03-01

119

Oral colonisation by aerobic and facultatively anaerobic Gram-negative rods and yeast in Tibetans living in Lhasa.  

PubMed

Sample groups of children (n=50) and adults (n=38) were selected from pools of 207 children, (11-13-year olds from two primary schools) and 94 adults (25-44-year olds from four governmental agencies) who were the subjects of an oral health survey among Tibetans living in Lhasa, Tibet Autonomous Region. Mean ages of the study groups of children (38% females) and adults (61% females) were 11.6+/-0.9 and 37.1+/-6.1 years, respectively. All had lived in Tibet since birth. Oral rinse samples were selective cultured to isolate, quantify and speciate aerobic and facultatively anaerobic Gram-negative rods (using the API 20E kit) and yeasts (using API 20C AUX and API ZYM kits). For children, the isolation rates for oral coliform bacteria and yeasts were 84 and 14%, respectively, for adults, the respective rates were 26 and 40%. The corresponding quantities of coliforms/yeasts for children and adults were 0.4+/-1.6 x 10(3)c.f.u./15.8+/-72.3 and 0.2+/-0.6 x 10(3)c.f.u./57.2+/-137.5c.f.u. per millilitre oral rinse, respectively. Aerobic and facultatively anaerobic Gram-negative rods and Stenotrophomonas maltophilia, a free-living saprophytic and ubiquitous bacterial species of wide geographic distribution, were significantly more frequently recovered from the children's oral rinses. The isolation rates of facultatively anaerobic Gram-negative rods in adults and yeasts in both groups were similar to those found in similar cohorts from southern China in earlier studies. Randomly amplified polymeric DNA analysis showed that the S. maltophilia spp. isolated from children were of several different clonal types and were school specific. This study shows that the colonisation rate of facultatively anaerobic Gram-negative rods in adults and yeasts in both groups are similar to those in populations living at lower altitudes, the native young, urban Tibetans appear to exhibit a high oral carriage rate of S. maltophilia spp. PMID:12642230

Leung, W K; Yau, J Y Y; Cheung, B P K; Jin, L J; Zee, K-Y; Lo, E C M; Samaranayake, L P; Corbet, E F

2003-02-01

120

DGGE with genomic DNA: suitable for detection of numerically important organisms but not for identification of the most abundant organisms.  

PubMed

Identification of all important community members as well as of the numerically dominant members of a community are key aspects of microbial community analysis of bioreactor samples. A systematic study was conducted with artificial consortia to test whether denaturing gradient gel electrophoresis (DGGE) is a reliable technique to obtain such community data under conditions where results would not be affected by differences in DNA extraction efficiency from cells. A total of 27 consortia were established by mixing DNA extracted from Escherichia coli K12, Burkholderia cepacia and Stenotrophomonas maltophilia in different proportions. Concentrations of DNA of single organisms in the consortia were either 0.04, 0.4 or 4ng/microl. DGGE-PCR of genomic DNA with primer sets targeted at the V3 and V6-V8 regions of the 16S rDNA failed to detect the three community members in only 7% of consortia, but provided incorrect information about dominance or co-dominance for 85% and 89% of consortia with the primer sets for the V6-V8 and V3 regions, respectively. The high failure rate in detection of dominant B. cepacia with the primers for the V6-V8 region was attributable to a single nucleotide primer mismatch in the target sequences of both, the forward and reverse primer. Amplification bias in PCR of E. coli and S. maltophilia for the V6-V8 region and for all three organisms for the V3 region occurred due to interference of genomic DNA in PCR-DGGE, since a nested PCR approach, where PCR-DGGE was started from mixtures of 16S rRNA genes of the organisms, provided correct information about the relative abundance of original DNA in the sample. Multiple bands were not observed in pure culture amplicons produced with the V6-V8 primer pair, but pure culture V3 DGGE profiles of E. coli, S. maltophilia and B. cepacia contained 5, 3 and 3 bands, respectively. These results demonstrate DGGE was suitable for identification of all important community members in the three-membered artificial consortium, but not for identification of the dominant organisms in this small community. Multiple DGGE bands obtained for single organisms with the V3 primer pair could greatly confound interpretation of DGGE profiles. PMID:18929384

de Araújo, Juliana Calábria; Schneider, René Peter

2008-12-01

121

Characterization of Contaminants from a Sanitized Milk Processing Plant  

PubMed Central

Milk processing lines offer a wide variety of microenvironments where a diversity of microorganisms can proliferate. We sampled crevices and junctions where, due to deficient reach by typical sanitizing procedures, bacteria can survive and establish biofilms. The sampling sites were the holding cell, cold storage tank, pasteurizer and storage tank - transfer pump junction. The culturable bacteria that were isolated after the sanitation procedure were predominantly Pseudomonas spp., Serratia spp, Staphylococcus sciuri and Stenotrophomonas maltophilia. We assayed several phenotypic characteristics such as the ability to secrete enzymes and siderophores, as well as the capacity of the strains to form biofilms that might contribute to their survival in a mixed species environment. The Pseudomonas spp. isolates were found to either produce proteases or lecithinases at high levels. Interestingly, protease production showed an inverse correlation with siderophore production. Furthermore, all of the Serratia spp. isolates were strong biofilm formers and spoilage enzymes producers. The organisms identified were not mere contaminants, but also producers of proteins with the potential to lower the quality and shelf-life of milk. In addition, we found that a considerable number of the Serratia and Pseudomonas spp. isolated from the pasteurizer were capable of secreting compounds with antimicrobial properties. PMID:22761957

Cleto, Sara; Matos, Sonia; Kluskens, Leon; Vieira, Maria Joao

2012-01-01

122

Production and characterization of monoclonal antibodies specific for the lipopolysaccharide of Escherichia coli O157.  

PubMed Central

Identification of the O157 antigen is an essential part of the detection of Escherichia coli O157:H7, which is recognized as a major etiologic agent of hemorrhagic colitis. However, polyclonal antibodies produced against E. coli O157:H7 lipopolysaccharide (LPS) may react with several other bacteria including Brucella abortus, Brucella melitensis, Yersinia enterocolitica O9, Escherichia hermannii, and Stenotrophomonas maltophilia. We produced eight monoclonal antibodies (MAbs) specific for the LPS of E. coli O157. Western blots (immunoblots) of both the phenol phase (smooth) and the aqueous phase (rough) of hot phenol-water-purified LPS indicated that three of the MAbs were specific for the O antigen and five were reactive with the LPS core. The eight MAbs could be further differentiated by their reactivities to Salmonella O30 LPS (group N), which is reported to be identical to the E. coli O157 antigen. All eight MAbs reacted strongly to all of the 64 strains of E. coli O157 tested, which included 47 isolates of O157:H7 and 17 other O157 strains. None of the eight MAbs cross-reacted with any of the 38 other E. coli serotypes tested, which consisted of 29 different O-antigen serotypes, or with 38 strains (22 genera) of non-E. coli gram-negative enteric bacteria. PMID:9041412

Westerman, R B; He, Y; Keen, J E; Littledike, E T; Kwang, J

1997-01-01

123

[Bacteremia with granulocytopenia--microbiology and empiric antibiotic treatment].  

PubMed

This article sums up a retrospective analysis of 84 episodes of bacteraemia in acute leukaemia patients with severe neutropenia in a Norwegian teaching hospital during the period 1990-95. Gram negative bacteria represented 54% of the blood culture isolates, all of which were susceptible to aminoglycosides, and nearly all to ceftazidime and imipenem. Penicillin/aminoglycoside was used as initial therapy in 43% of the episodes. Initial empiric therapy was modified in 52% of the events. Only 15% of patients receiving the penicillin/aminoglycoside combination actually had infections with organisms susceptible to penicillin. Only 2% of patients with gram negative infections received initial synergistic treatment with two effective drugs. Mortality from infections was 8% in acute leukaemia patients with documented bacteraemia. Deaths mainly occurred in patients with terminal leukaemia disease. Late breakthrough bacteraemias with Stenotrophomonas maltophilia and Pseudomonas aeruginosa caused 50% of all fatal infections. The analysis suggests that no patients died during initial bacteraemia with penicillin-resistant organisms treated with penicillin/aminoglycoside. The antibiotic susceptibility of the isolated bacteria was favourable compared to what has been found in other countries. For the time being, we believe that the ecological advantages of using penicillin/aminoglycoside as initial empiric treatment of febrile neutropenia are greater than the disadvantages. PMID:9889610

Hammerstrøm, J; Jacobsen, T

1998-11-20

124

Antimicrobial activity of novel nanostructured Cu-SiO2 coatings prepared by chemical vapour deposition against hospital related pathogens  

PubMed Central

There is increasing recognition that the healthcare environment acts as an important reservoir for transmission of healthcare acquired infections (HCAI). One method of reducing environmental contamination would be use of antimicrobial materials. The antimicrobial activity of thin silica-copper films prepared by chemical vapour deposition was evaluated against standard strains of bacteria used for disinfectant testing and bacteria of current interest in HCAI. The structure of the coatings was determined using Scanning Electron Microscopy and their hardness and adhesion to the substrate determined. Antimicrobial activity was tested using a method based on BS ISO 22196:2007. The coatings had a pale green-brown colour and had a similar hardness to steel. SEM showed nano-structured aggregates of Cu within a silica matrix. A log10 reduction in viability of >5 could be obtained within 4 h for the disinfectant test strains and within 6 h for producing Acinetobacter baumannii, Klebsiella pneumoniae and Stenotrophomonas maltophilia. Activity against the other hospital isolates was slower but still gave log10 reduction factors of >5 for extended spectrum ?-lactamase producing Escherichia coli and >3 for vancomycin resistant Enterococcus faecium, methicillin resistant Staphylococcus aureus and Pseudomonas aeruginosa within 24 h. The results demonstrate the importance of testing antimicrobial materials destined for healthcare use against isolates of current interest in hospitals as well as standard test strains. The coatings used here can also be applied to substrates such as metals and ceramics and have potential applications where reduction of microbial environmental contamination is desirable. PMID:24007899

2013-01-01

125

Effects of a sulfonylurea herbicide on the soil bacterial community.  

PubMed

Sulfonylurea herbicides are widely used on a wide range of crops to control weeds. Chevalier® OnePass herbicide is a sulfonylurea herbicide intensively used on cereal crops in Algeria. No information is yet available about the biodegradation of this herbicide or about its effect on the bacterial community of the soil. In this study, we collected an untreated soil sample, and another sample was collected 1 month after treatment with the herbicide. Using a high-resolution melting DNA technique, we have shown that treatment with Chevalier® OnePass herbicide only slightly changed the composition of the whole bacterial community. Two hundred fifty-nine macroscopically different clones were isolated from the untreated and treated soil under both aerobic and microaerobic conditions. The strains were identified by sequencing a conserved fragment of the 16S rRNA gene. The phylogenetic trees constructed using the sequencing results confirmed that the bacterial populations were similar in the two soil samples. Species belonging to the Lysinibacillus, Bacillus, Pseudomonas, and Paenibacillus genera were the most abundant species found. Surprisingly, we found that among ten strains isolated from the treated soil, only six were resistant to the herbicide. Furthermore, bacterial overlay experiments showed that only one resistant strain (related to Stenotrophomonas maltophilia) allowed all the sensitive strains tested to grow in the presence of the herbicide. The other resistant strains allowed only certain sensitive strains to grow. On the basis of these results, we propose that there must be several biodegradation pathways for this sulfonylurea herbicide. PMID:24420563

Arabet, Dallel; Tempel, Sébastien; Fons, Michel; Denis, Yann; Jourlin-Castelli, Cécile; Armitano, Joshua; Redelberger, David; Iobbi-Nivol, Chantal; Boulahrouf, Abderrahmane; Méjean, Vincent

2014-04-01

126

Bacterial contamination of water in dental unit reservoirs.  

PubMed

The aim of this study was bacteriological assessment of water in dental unit reservoirs--concentration and composition of the aerobe and facultative anaerobe bacterial microflora. Reservoir water samples were taken from 25 units. Bacterial flora were determined with the plate culture method. Bacteria were identified with biochemical microtests: API 20E, API 20NE (bioMérieux, France) and GP2 MicroPlateTM (BIOLOG, USA). The concentration of total bacteria isolated from one site was 201,039 cfu/ml, on average; the minimum was 22,300 cfu/ml, and the maximum - 583,000 cfu/ml. The following bacteria were identified: Gram-negative bacteria--Brevundimonas vesicularis, Moraxella lacunata, Moraxella spp., Ralstonia pickettii, Sphingomonas paucimobilis, Stenotrophomonas maltophilia; Gram-positive cocci--Micrococcus luteus, Micrococcus lylae, Staphylococcus cohnii, Staphylococcus hominis ss novobiosepticus, Staphylococcus spp., Streptococcus spp.; actinomycetes--Streptomyces albus. The prevailing bacteria were: Ralstonia pickettii (96.46%), found in all the units. Sphingomonas paucimobilis (1.32%) and Brevundimonas vesicularis (1.07%) were the next most frequently occurring bacteria. Bacteria concentration in dental unit reservoirs reached excessive values, and the bacterial flora were composed of the bacteria characteristic for water supply systems, opportunistic pathogens, and bacteria of the oral cavity flora. Continuous microbiological monitoring of the DUWL water, including application of a disinfecting procedure, is necessary. PMID:17655191

Szyma?ska, Jolanta

2007-01-01

127

Ciprofloxacin-Resistant Gram-Negative Bacilli in the Fecal Microflora of Children  

PubMed Central

The extent to which antibiotic-resistant bacteria are excreted by humans who have not been exposed to antibiotics is not known. Children, who rarely receive fluoroquinolones, provide opportunities to assess the frequency of fecal excretion by fluoroquinolone-naïve hosts of fluoroquinolone-resistant gram-negative bacilli. Fresh nondiarrheal stools from children were processed by screening them on agar containing ciprofloxacin to recover ciprofloxacin-resistant gram-negative bacilli. Resistant isolates were identified, and ciprofloxacin MICs were determined. Resistant Escherichia coli isolates were also analyzed for urovirulence-associated loci. Thirteen (2.9%) of 455 stools yielded ciprofloxacin-resistant E. coli (seven children), Stenotrophomonas maltophilia (four children), and Achromobacter xylosoxidans and Enterobacter aerogenes (one child each). Neither the subjects themselves nor members of their households used fluoroquinolones in the 4 weeks preceding collection. Six of the seven resistant E. coli isolates belonged to phylogenetic groups B2 and D, in which extraintestinal pathogenic E. coli bacteria are frequently found. All resistant E. coli isolates contained at least three putative E. coli virulence loci. Most ciprofloxacin-resistant bacteria were resistant to additional antibiotics. Potentially pathogenic bacteria that are resistant to therapeutically important antimicrobial agents are excreted by some humans, despite these persons' lack of exposure to the particular drugs. The sources of these resistant organisms are unknown. This underrecognized reservoir of drug-resistant potential pathogens poses public health challenges. PMID:17005812

Qin, Xuan; Razia, Yasmin; Johnson, James R.; Stapp, Jennifer R.; Boster, Daniel R.; Tsosie, Treva; Smith, Donna L.; Braden, Christopher R.; Gay, Kathryn; Angulo, Frederick J.; Tarr, Phillip I.

2006-01-01

128

Combination of photoreactor and packed bed bioreactor for the removal of ethyl violet from wastewater.  

PubMed

An efficient treatment system that combines a photoreactor and packed bed bioreactor (PBR) was developed and evaluated for treating ethyl violet (EV)-containing wastewater. Initial experiments demonstrated that the optimal operating parameters for the photoreactor in treating EV-containing wastewater were 2h reaction time, pH of 7, and 2min liquid retention time. Under these conditions, the photocatalytic reaction achieved a 61% EV removal efficiency and resulted in a significant BOD/COD increase in the solution. The results displayed by the coupled photobiological system achieved a removal efficiency of 85% and EC50 of the solution increased by 19 times in a semi-continuous mode when the EV concentration was <150mgL(-)(1). The effect of shock loading on the EV removal was temporary but coexisting substrate (glucose and crystal violet) at specific levels would affect the EV removal efficiency of the PBR. Phylogenetic analysis in the PBR indicated that the major bacteria species were Bdellovibrio bacteriovorus, Ralstonia pickettii, Stenotrophomonas maltophilia, and Comamonas sp. Furthermore, the possible degrading mechanisms of this coupled system were demethylation, deethylation, aromatic ring opening, nitrification, and carbon oxidation. The intermediates were characterized using gas chromatography-mass spectrometry analysis. These results indicated that the coupled photobiological system provides an effective method of EV removal. PMID:25259784

Chen, Chih-Yu; Yen, Shao-Hsiung; Chung, Ying-Chien

2014-12-01

129

Production and characterization of monoclonal antibodies specific for the lipopolysaccharide of Escherichia coli O157.  

PubMed

Identification of the O157 antigen is an essential part of the detection of Escherichia coli O157:H7, which is recognized as a major etiologic agent of hemorrhagic colitis. However, polyclonal antibodies produced against E. coli O157:H7 lipopolysaccharide (LPS) may react with several other bacteria including Brucella abortus, Brucella melitensis, Yersinia enterocolitica O9, Escherichia hermannii, and Stenotrophomonas maltophilia. We produced eight monoclonal antibodies (MAbs) specific for the LPS of E. coli O157. Western blots (immunoblots) of both the phenol phase (smooth) and the aqueous phase (rough) of hot phenol-water-purified LPS indicated that three of the MAbs were specific for the O antigen and five were reactive with the LPS core. The eight MAbs could be further differentiated by their reactivities to Salmonella O30 LPS (group N), which is reported to be identical to the E. coli O157 antigen. All eight MAbs reacted strongly to all of the 64 strains of E. coli O157 tested, which included 47 isolates of O157:H7 and 17 other O157 strains. None of the eight MAbs cross-reacted with any of the 38 other E. coli serotypes tested, which consisted of 29 different O-antigen serotypes, or with 38 strains (22 genera) of non-E. coli gram-negative enteric bacteria. PMID:9041412

Westerman, R B; He, Y; Keen, J E; Littledike, E T; Kwang, J

1997-03-01

130

Blooms of Single Bacterial Species in a Coastal Lagoon of the Southwestern Atlantic Ocean  

PubMed Central

We investigated seasonal differences in community structure and activity (leucine incorporation) of the planktonic bacterial assemblage in the freshwater and brackish-water zones of a shallow coastal lagoon of the southwestern Atlantic Ocean. Alphaproteobacteria formed the dominant microbial group in both zones throughout the sampling period. After an intrusion of marine water, members of the SAR11 lineage became abundant in the brackish-water zone. These bacteria were apparently distributed over the lagoon during the following months until they constituted almost 30% of all prokaryotic cells at both sampling sites. At the first sampling date (March 2003) a single alphaproteobacterial species unrelated to SAR11, Sphingomonas echinoides, dominated the microbial assemblages in both zones of the lagoon concomitantly with a bloom of filamentous cyanobacteria. Pronounced maxima of leucine incorporation were observed once in each zone of the lagoon. In the freshwater zone, this highly active microbial assemblage was a mix of the typical bacteria lineages expected in aquatic systems. By contrast, a single bacterial genotype with >99% similarity to the facultative pathogen gammaproteobacterial species Stenotrophomonas maltophilia formed >90% of the bacterial assemblage (>107 cell ml?1) in the brackish-water zone at the time point of highest bacterial leucine incorporation. Moreover, these bacteria were equally dominant, albeit less active, in the freshwater zone. Thus, the pelagic zone of the studied lagoon harbored repeated short-term blooms of single bacterial species. This finding may have consequences for environmental protection. PMID:17021206

Piccini, Claudia; Conde, Daniel; Alonso, Cecilia; Sommaruga, Ruben; Pernthaler, Jakob

2006-01-01

131

Diaryl-Substituted Azolylthioacetamides: Inhibitor Discovery of New Delhi Metallo-?-Lactamase-1 (NDM-1).  

PubMed

The emergence and spread of antibiotic-resistant pathogens is a global public health problem. Metallo-?-lactamases (M?Ls) such as New Delhi M?L-1 (NDM-1) are principle contributors to the emergence of resistance because of their ability to hydrolyze almost all known ?-lactam antibiotics including penicillins, cephalosporins, and carbapenems. A clinical inhibitor of MBLs has not yet been found. In this study we developed eighteen new diaryl-substituted azolylthioacetamides and found all of them to be inhibitors of the M?L L1 from Stenotrophomonas maltophilia (Ki <2??M), thirteen to be mixed inhibitors of NDM-1 (Ki <7??M), and four to be broad-spectrum inhibitors of all four tested M?Ls CcrA from Bacteroides fragilis, NDM-1 and ImiS from Aeromonas veronii, and L1 (Ki <52??M), which are representative of the B1a, B1b, B2, and B3 subclasses, respectively. Docking studies revealed that the azolylthioacetamides, which have the broadest inhibitory activity, coordinate to the Zn(II) ion(s) preferentially via the triazole moiety, while other moieties interact mostly with the conserved active site residues Lys224 (CcrA, NDM-1, and ImiS) or Ser221 (L1). PMID:25048031

Zhang, Yi-Lin; Yang, Ke-Wu; Zhou, Ya-Jun; LaCuran, Alecander E; Oelschlaeger, Peter; Crowder, Michael W

2014-11-01

132

Isolation and characterization of phenol utilizing bacteria from industrial effluent-contaminated soil and kinetic evaluation of their biodegradation potential.  

PubMed

Microbial degradation of phenol by pure bacterial species is a well-known approach towards alleviation of environmental pollution. In this study, five phenol-degrading bacterial species designated as CUPS-1 to CUPS-5 were isolated from the oil-effluent dumped sites of Haldia Industrial area of West Bengal, India. Detailed morphological, biochemical and molecular characterization identified CUPS-3 as a novel strain- Stenotrophomonas maltophilia (GU358076), while the others could be identified as Pseudomonas (CUPS-2, 5), Delftia (CUPS-1) and Micrococcus (CUPS-4) genera, respectively. Although all of these strains utilized phenol as their sole carbon source supporting growth, three among them, CUPS-2, CUPS-3 and CUPS-5 proved potential phenol degraders and hence used for further biodegradation studies. Degradation experiments were carried out for several initial phenol concentrations of 500 mg/L, 750 mg/L, 1000 mg/L, 1250 mg/L and 1500 mg/L. The novel strain, CUPS-3 could completely degrade 500 mg/L phenol within 48 h, with 0.0937/h substrate degradation rate and 16.34 mg/L/h substrate consumption rate. The strains degraded phenol via meta-cleavage pathway. Prediction of kinetic parameters of the biodegradation was accomplished Haldane model using the experimental data of degradation rate and phenol concentration as function of time. PMID:24117085

Pal Basak, Sreela; Sarkar, Priyabrata; Pal, Priyabrata

2014-01-01

133

Rosmarinic Acid from Eelgrass Shows Nematicidal and Antibacterial Activities against Pine Wood Nematode and Its Carrying Bacteria  

PubMed Central

Pine wilt disease (PWD), a destructive disease for pine trees, is caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus and additional bacteria. In this study, extracts of Zostera marina showed a high nematicidal activity against PWN and some of the bacteria that it carries. Light yellow crystals were obtained from extracts of Z. marina through solvent extraction, followed by chromatography on AB-8 resin and crystallization. The NMR and HPLC analysis showed that the isolated compound was rosmarinic acid (RosA). RosA showed effective nematicidal activity, of which the LC50 (50% lethal concentration) to PWN at 24 h, 48 h and 72 h was 1.18 mg/g, 1.05 mg/g and 0.95 mg/g, respectively. To get a high yield rate of RosA from Z. marina, single factor experiments and an L9 (34) orthogonal experiment were performed. This extraction process involved 70% ethanol for 3 h at 40 °C. The extraction dosage was 1:50 (w/v). The highest yield of RosA from Zostera was 3.13 mg/g DW (dried weight). The crude extracts of Zostera marina (10 mg/mL) and RosA (1 mg/mL) also showed inhibitory effects to some bacterial strains carried by PWN: Klebsiella sp., Stenotrophomonas maltophilia, Streptomyces sp. and Pantoea agglomerans. The results of these studies provide clues for preparing pesticide to control PWD from Z. marina. PMID:23201594

Wang, Jingyu; Pan, Xueru; Han, Yi; Guo, Daosen; Guo, Qunqun; Li, Ronggui

2012-01-01

134

An L-glucitol oxidizing dehydrogenase from Bradyrhizobium japonicum USDA 110 for production of D-sorbose with enzymatic or electrochemical cofactor regeneration.  

PubMed

A gene in Bradyrhizobium japonicum USDA 110, annotated as a ribitol dehydrogenase (RDH), had 87 % sequence identity (97 % positives) to the N-terminal 31 amino acids of an L-glucitol dehydrogenase from Stenotrophomonas maltophilia DSMZ 14322. The 729-bp long RDH gene coded for a protein consisting of 242 amino acids with a molecular mass of 26.1 kDa. The heterologously expressed protein not only exhibited the main enantio selective activity with D-glucitol oxidation to D-fructose but also converted L-glucitol to D-sorbose with enzymatic cofactor regeneration and a yield of 90 %. The temperature stability and the apparent K m value for L-glucitol oxidation let the enzyme appear as a promising subject for further improvement by enzyme evolution. We propose to rename the enzyme from the annotated RDH gene (locus tag bll6662) from B. japonicum USDA as a D-sorbitol dehydrogenase (EC 1.1.1.14). PMID:24061413

Gauer, Sabrina; Wang, Zhijie; Otten, Harm; Etienne, Mathieu; Bjerrum, Morten Jannik; Lo Leggio, Leila; Walcarius, Alain; Giffhorn, Friedrich; Kohring, Gert-Wieland

2014-04-01

135

Anti-infective properties of epigallocatechin-3-gallate (EGCG), a component of green tea  

PubMed Central

The consumption of green tea (Camellia sinensis) has been shown to have many physiological and pharmacological health benefits. In the past two decades several studies have reported that epigallocatechin-3-gallate (EGCG), the main constituent of green tea, has anti-infective properties. Antiviral activities of EGCG with different modes of action have been demonstrated on diverse families of viruses, such as Retroviridae, Orthomyxoviridae and Flaviviridae and include important human pathogens like human immunodeficiency virus, influenza A virus and the hepatitis C virus. Furthermore, the molecule interferes with the replication cycle of DNA viruses like hepatitis B virus, herpes simplex virus and adenovirus. Most of these studies demonstrated antiviral properties within physiological concentrations of EGCG in vitro. In contrast, the minimum inhibitory concentrations against bacteria were 10–100-fold higher. Nevertheless, the antibacterial effects of EGCG alone and in combination with different antibiotics have been intensively analysed against a number of bacteria including multidrug-resistant strains such as methicillin-resistant Staphylococcus aureus or Stenotrophomonas maltophilia. Furthermore, the catechin EGCG has antifungal activity against human-pathogenic yeasts like Candida albicans. Although the mechanistic effects of EGCG are not fully understood, there are results indicating that EGCG binds to lipid membranes and affects the folic acid metabolism of bacteria and fungi by inhibiting the cytoplasmic enzyme dihydrofolate reductase. This review summarizes the current knowledge and future perspectives on the antibacterial, antifungal and antiviral effects of the green tea constituent EGCG. PMID:23072320

Steinmann, J; Buer, J; Pietschmann, T; Steinmann, E

2013-01-01

136

Anti-infective properties of epigallocatechin-3-gallate (EGCG), a component of green tea.  

PubMed

The consumption of green tea (Camellia sinensis) has been shown to have many physiological and pharmacological health benefits. In the past two decades several studies have reported that epigallocatechin-3-gallate (EGCG), the main constituent of green tea, has anti-infective properties. Antiviral activities of EGCG with different modes of action have been demonstrated on diverse families of viruses, such as Retroviridae, Orthomyxoviridae and Flaviviridae and include important human pathogens like human immunodeficiency virus, influenza A virus and the hepatitis C virus. Furthermore, the molecule interferes with the replication cycle of DNA viruses like hepatitis B virus, herpes simplex virus and adenovirus. Most of these studies demonstrated antiviral properties within physiological concentrations of EGCG in vitro. In contrast, the minimum inhibitory concentrations against bacteria were 10-100-fold higher. Nevertheless, the antibacterial effects of EGCG alone and in combination with different antibiotics have been intensively analysed against a number of bacteria including multidrug-resistant strains such as methicillin-resistant Staphylococcus aureus or Stenotrophomonas maltophilia. Furthermore, the catechin EGCG has antifungal activity against human-pathogenic yeasts like Candida albicans. Although the mechanistic effects of EGCG are not fully understood, there are results indicating that EGCG binds to lipid membranes and affects the folic acid metabolism of bacteria and fungi by inhibiting the cytoplasmic enzyme dihydrofolate reductase. This review summarizes the current knowledge and future perspectives on the antibacterial, antifungal and antiviral effects of the green tea constituent EGCG. PMID:23072320

Steinmann, J; Buer, J; Pietschmann, T; Steinmann, E

2013-03-01

137

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae)  

PubMed Central

Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. ( B. cereus, B. megaterium, B. pumilus and B. subtilis ) , Paenibacillus sp. , Amphibacillus sp. , Gracilibacillus sp. , Micrococcus sp. and Stenotrophomonas spp. ( S. maltophilia and S. nitroreducens ). B. pumilus was the most frequently isolated bacterial species . Amphibacillus and Gracilibacillus were reported as endophytes for the first time. Other commonly found bacterial genera were not observed in D. sellowiana , which may reflect preferences of specific bacterial communities inside this fern or detection limitations due to the isolation procedures. Plants that were grown in greenhouses and plants that were reintroduced into the forest displayed more bacterial genera and species diversity than native field plants, suggesting that reintroduction shifts the bacterial diversity. Endophytic bacteria that displayed antagonistic properties against different microorganisms were detected, but no obvious correlation was found between their frequencies with plant tissues or with plants from different growth regimes. This paper reports the first isolation of endophytic bacteria from a fern. PMID:24031575

de Araújo Barros, Irene; Luiz Araújo, Welington; Lúcio Azevedo, João

2010-01-01

138

Low Rates of Pseudomonas aeruginosa Misidentification in Isolates from Cystic Fibrosis Patients?  

PubMed Central

Pseudomonas aeruginosa is an important cause of pulmonary infection in cystic fibrosis (CF). Its correct identification ensures effective patient management and infection control strategies. However, little is known about how often CF sputum isolates are falsely identified as P. aeruginosa. We used P. aeruginosa-specific duplex real-time PCR assays to determine if 2,267 P. aeruginosa sputum isolates from 561 CF patients were correctly identified by 17 Australian clinical microbiology laboratories. Misidentified isolates underwent further phenotypic tests, amplified rRNA gene restriction analysis, and partial 16S rRNA gene sequence analysis. Participating laboratories were surveyed on how they identified P. aeruginosa from CF sputum. Overall, 2,214 (97.7%) isolates from 531 (94.7%) CF patients were correctly identified as P. aeruginosa. Further testing with the API 20NE kit correctly identified only 34 (59%) of the misidentified isolates. Twelve (40%) patients had previously grown the misidentified species in their sputum. Achromobacter xylosoxidans (n = 21), Stenotrophomonas maltophilia (n = 15), and Inquilinus limosus (n = 4) were the species most commonly misidentified as P. aeruginosa. Overall, there were very low rates of P. aeruginosa misidentification among isolates from a broad cross section of Australian CF patients. Additional improvements are possible by undertaking a culture history review, noting colonial morphology, and performing stringent oxidase, DNase, and colistin susceptibility testing for all presumptive P. aeruginosa isolates. Isolates exhibiting atypical phenotypic features should be evaluated further by additional phenotypic or genotypic identification techniques. PMID:19261796

Kidd, Timothy J.; Ramsay, Kay A.; Hu, Honghua; Bye, Peter T. P.; Elkins, Mark R.; Grimwood, Keith; Harbour, Colin; Marks, Guy B.; Nissen, Michael D.; Robinson, Philip J.; Rose, Barbara R.; Sloots, Theo P.; Wainwright, Claire E.; Bell, Scott C.

2009-01-01

139

Risk factors for hospital-acquired pneumonia caused by carbapenem-resistant Gram-negative bacteria in critically ill patients: a multicenter study in Korea.  

PubMed

We performed a case-control study to identify risk factors of carbapenem-resistant Gram-negative bacteria (CRGNB) as an increasing cause of hospital-acquired pneumonia (HAP). The study included critically ill adult patients with HAP whose microbial etiology was identified at eight tertiary centers in Korea between June 2008 and December 2009. Eighty two patients with 86 isolates of CRGNB (62 Acinetobacter baumannii, 14 Pseudomonas aeruginosa, and 10 Stenotrophomonas maltophilia) were included in the case group, and 122 patients with carbapenem-susceptible Gram-negative bacteria were included in the control group. Diabetes mellitus (adjusted odds ratio [aOR] 2.82, 95% confidence interval [95% CI] 1.25-6.38), radiologic score ?5 (aOR 4.56, 95% CI 2.36-8.81), prior fluoroquinolone (aOR 2.39. 95% CI = 1.07-5.35), or carbapenem usage (aOR 2.82, 95% CI 1.75-17.83) were found to be independent risk factors. Fluoroquinolone and carbapenem should be cautiously used to avoid HAP caused by CRGNB. PMID:24462178

Kim, Tark; Chong, Yong Pil; Park, Seong Yeon; Jeon, Min-Hyok; Choo, Eun Joo; Chung, Jin-Won; Lee, Hyun Kyung; Moon, Chisook; Kim, Dong-Min; Peck, Kyong Ran; Kim, Yang Soo

2014-04-01

140

Adaptive Plasmid Evolution Results in Host-Range Expansion of a Broad-Host-Range Plasmid  

PubMed Central

Little is known about the range of hosts in which broad-host-range (BHR) plasmids can persist in the absence of selection for plasmid-encoded traits, and whether this “long-term host range” can evolve over time. Previously, the BHR multidrug resistance plasmid pB10 was shown to be highly unstable in Stenotrophomonas maltophilia P21 and Pseudomonas putida H2. To investigate whether this plasmid can adapt to such unfavorable hosts, we performed evolution experiments wherein pB10 was maintained in strain P21, strain H2, and alternatingly in P21 and H2. Plasmids that evolved in P21 and in both hosts showed increased stability and decreased cost in ancestral host P21. However, the latter group showed higher variability in stability patterns, suggesting that regular switching between distinct hosts hampered adaptive plasmid evolution. The plasmids evolved in P21 were also equally or more stable in other hosts compared to pB10, which suggested true host-range expansion. The complete genome sequences of four evolved plasmids with improved stability showed only one or two genetic changes. The stability of plasmids evolved in H2 improved only in their coevolved hosts, not in the ancestral host. Thus a BHR plasmid can adapt to an unfavorable host and thereby expand its long-term host range. PMID:18430943

De Gelder, Leen; Williams, Julia J.; Ponciano, Jose M.; Sota, Masahiro; Top, Eva M.

2008-01-01

141

Adaptive plasmid evolution results in host-range expansion of a broad-host-range plasmid.  

PubMed

Little is known about the range of hosts in which broad-host-range (BHR) plasmids can persist in the absence of selection for plasmid-encoded traits, and whether this "long-term host range" can evolve over time. Previously, the BHR multidrug resistance plasmid pB10 was shown to be highly unstable in Stenotrophomonas maltophilia P21 and Pseudomonas putida H2. To investigate whether this plasmid can adapt to such unfavorable hosts, we performed evolution experiments wherein pB10 was maintained in strain P21, strain H2, and alternatingly in P21 and H2. Plasmids that evolved in P21 and in both hosts showed increased stability and decreased cost in ancestral host P21. However, the latter group showed higher variability in stability patterns, suggesting that regular switching between distinct hosts hampered adaptive plasmid evolution. The plasmids evolved in P21 were also equally or more stable in other hosts compared to pB10, which suggested true host-range expansion. The complete genome sequences of four evolved plasmids with improved stability showed only one or two genetic changes. The stability of plasmids evolved in H2 improved only in their coevolved hosts, not in the ancestral host. Thus a BHR plasmid can adapt to an unfavorable host and thereby expand its long-term host range. PMID:18430943

De Gelder, Leen; Williams, Julia J; Ponciano, José M; Sota, Masahiro; Top, Eva M

2008-04-01

142

Assessing the xylanolytic bacterial diversity during the malting process.  

PubMed

The presence of microorganisms producing cell wall hydrolyzing enzymes such as xylanases during malting can improve mash filtration behavior and consequently have potential for more efficient wort production. In this study, the xylanolytic bacterial community during malting was assessed by isolation and cultivation on growth media containing arabinoxylan, and identification by 16S rRNA gene sequencing. A total of 33 species-level operational taxonomic units (OTUs) were found, taking into account a 3% sequence dissimilarity cut-off, belonging to four phyla (Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria) and 25 genera. Predominant OTUs represented xylanolytic bacteria identified as Sphingobacterium multivorum, Stenotrophomonas maltophilia, Aeromonas hydrophila and Pseudomonas fulva. DNA fingerprinting of all xylanolytic isolates belonging to S. multivorum obtained in this study revealed shifts in S. multivorum populations during the process. Xylanase activity was determined for a selection of isolates, with Cellulomonas flavigena showing the highest activity. The xylanase of this species was isolated and purified 23.2-fold by ultrafiltration, 40% ammonium sulfate precipitation and DEAE-FF ion-exchange chromatography and appeared relatively thermostable. This study will enhance our understanding of the role of microorganisms in the barley germination process. In addition, this study may provide a basis for microflora management during malting. PMID:24010623

Malfliet, Sofie; Justé, Annelies; Crauwels, Sam; Willems, Kris; De Cooman, Luc; Lievens, Bart; Aerts, Guido

2013-12-01

143

Capillary isoelectric focusing of proteins and microorganisms in dynamically modified fused silica with UV detection.  

PubMed

We suggest a method for the reproducible and efficient capillary isoelectric focusing of proteins and microorganisms in the pH gradient 3-10. The method involves the segmental injection of the simple ampholytes, the solution of the selected electrolytes, and the sample mixture of bioanalytes and carrier ampholytes to the fused silica capillaries dynamically modified by poly(ethylene glycol), PEG 4000, which is added to the catholyte, the anolyte and injected solutions. In order to receive the reproducible results, the capillaries were rinsed by the mixture of acetone/ethanol between analyses. For the tracing of the pH gradients the low-molecular-mass pI markers were used. The simple proteins and the mixed cultures of microorganisms, Saccharomyces cerevisiae CCM 8191, Escherichia coli CCM 3954, Candida albicans CCM 8180, Candida parapsilosis, Candida krusei, Staphylococcus aureus, Streptococcus agalactiae CCM 6187, Enterococcus faecalis CCM 4224, Staphylococcus epidermidis CCM 4418 and Stenotrophomonas maltophilia, were focused and separated by the method suggested. The minimum detectable number of microbial cells was 5x10(2) to 1x10(3) with on-column UV detection at 280 nm. PMID:16765111

Horká, Marie; R?zicka, Filip; Horký, Jaroslav; Holá, Veronika; Slais, Karel

2006-09-01

144

Carbazole angular dioxygenation and mineralization by bacteria isolated from hydrocarbon-contaminated tropical African soil.  

PubMed

Four bacterial strains isolated from hydrocarbon-contaminated soils in Lagos, Nigeria, displayed extensive degradation abilities on carbazole, an N-heterocyclic aromatic hydrocarbon. Physicochemical analyses of the sampling sites (ACPP, MWO, NESU) indicate gross pollution of the soils with a high hydrocarbon content (157,067.9 mg/kg) and presence of heavy metals. Phylogenetic analysis of the four strains indicated that they were identified as Achromobacter sp. strain SL1, Pseudomonas sp. strain SL4, Microbacterium esteraromaticum strain SL6, and Stenotrophomonas maltophilia strain BA. The rates of degradation of carbazole by the four isolates during 30 days of incubation were 0.057, 0.062, 0.036, and 0.050 mg L(-1) h(-1) for strains SL1, SL4, SL6, and BA. Gas chromatographic (GC) analyses of residual carbazole after 30 days of incubation revealed that 81.3, 85, 64.4, and 76 % of 50 mg l(-1) carbazole were degraded by strains SL1, SL4, SL6, and BA, respectively. GC-mass spectrometry and high-performance liquid chromatographic analyses of the extracts from the growing and resting cells of strains SL1, SL4, and SL6 cultured on carbazole showed detection of anthranilic acid and catechol while these metabolites were not detected in strain BA under the same conditions. This study has established for the first time carbazole angular dioxygenation and mineralization by isolates from African environment. PMID:24728574

Salam, L B; Ilori, M O; Amund, O O; Numata, M; Horisaki, T; Nojiri, H

2014-08-01

145

In vitro and in vivo antibacterial activities of CS-834, a new oral carbapenem.  

PubMed

CS-834 is a prodrug of the carbapenem R-95867, developed by Sankyo Co., Ltd., Tokyo, Japan. To investigate the possibility that CS-834 may be the first carbapenem usable in an oral dosage form, its in vitro antibacterial activity (as R-95867) and in vivo antibacterial activity were compared with those of cefpodoxime proxetil, cefditoren pivoxil, cefdinir, ofloxacin, imipenem, and amoxicillin. R-95867 had high levels of activity against methicillin-susceptible staphylococci and streptococci, including penicillin-resistant Streptococcus pneumoniae, as well as Neisseria gonorrhoeae, Moraxella catarrhalis, the members of the family Enterobacteriaceae (with the exception of Serratia marcescens), Haemophilus influenzae, and Bordetella pertussis; for all these strains, the MICs at which 90% of tested strains are inhibited (MIC90s) were 1.0 microg/ml or less. Against methicillin-resistant staphylococci, enterococci, Serratia marcescens, Burkholderia cepacia, Stenotrophomonas maltophilia, and Acinetobacter calcoaceticus, R-95867 showed activity comparable to or slightly less than that of imipenem, with MIC90s ranging from 2 to >128 microg/ml. The in vivo efficacy of oral CS-834 against experimental mouse septicemia caused by gram-positive and gram-negative bacteria was better than that of comparative drugs. In murine respiratory infection models, the efficacy of CS-834 reflected not only its potent in vitro activity but also the high levels present in the lungs. PMID:9517932

Yamaguchi, K; Domon, H; Miyazaki, S; Tateda, K; Ohno, A; Ishii, K; Matsumoto, T; Furuya, N

1998-03-01

146

In Vitro and In Vivo Antibacterial Activities of CS-834, a New Oral Carbapenem  

PubMed Central

CS-834 is a prodrug of the carbapenem R-95867, developed by Sankyo Co., Ltd., Tokyo, Japan. To investigate the possibility that CS-834 may be the first carbapenem usable in an oral dosage form, its in vitro antibacterial activity (as R-95867) and in vivo antibacterial activity were compared with those of cefpodoxime proxetil, cefditoren pivoxil, cefdinir, ofloxacin, imipenem, and amoxicillin. R-95867 had high levels of activity against methicillin-susceptible staphylococci and streptococci, including penicillin-resistant Streptococcus pneumoniae, as well as Neisseria gonorrhoeae, Moraxella catarrhalis, the members of the family Enterobacteriaceae (with the exception of Serratia marcescens), Haemophilus influenzae, and Bordetella pertussis; for all these strains, the MICs at which 90% of tested strains are inhibited (MIC90s) were 1.0 ?g/ml or less. Against methicillin-resistant staphylococci, enterococci, Serratia marcescens, Brukholderia cepacia, Stenotrophomonas maltophilia, and Acinetobacter calcoaceticus, R-95867 showed activity comparable to or slightly less than that of imipenem, with MIC90s ranging from 2 to >128 ?g/ml. The in vivo efficacy of oral CS-834 against experimental mouse septicemia caused by gram-positive and gram-negative bacteria was better than that of comparative drugs. In murine respiratory infection models, the efficacy of CS-834 reflected not only its potent in vitro activity but also the high levels present in the lungs. PMID:9517932

Yamaguchi, Keizo; Domon, Haruki; Miyazaki, Shuichi; Tateda, Kazuhiro; Ohno, Akira; Ishii, Kazuhiro; Matsumoto, Tetsuya; Furuya, Nobuhiko

1998-01-01

147

Investigation of bacterial pathogens on 70 frequently used environmental surfaces in a large urban U.S. university.  

PubMed

After reports of increased severity of bacterial infections from community institutions, a broad spectrum of 70 surfaces was sampled for potential bacterial pathogens in the morning and afternoon of one day per week over three consecutive weeks in a large U.S. university. Surfaces included public telephone mouthpieces, water fountain drains, student computer keyboards and desks, and buttons on elevators, vending machines, and photocopiers. A total of 420 samples was obtained. Bacterial counts were high on telephone mouthpieces, up to 168.8 colony-forming units (CFUs).cm(-2) of surface area. Stenotrophomonas maltophilia was isolated from 60% of fountain drains. Ninety percent of the keyboards showed positive bacterial cultures in the afternoon sampling. Staphylococcus aureus was identified on keyboards, telephone mouthpieces, and an elevator button. No S. aureus were methicillin-resistant. The swab sampling method reduced bacterial counts to less than or equal to 2.0 CFU.cm(-2) on keyboards and telephone mouthpieces. Disinfectants for possible use in cleaning of telephones, water fountain drains, and keyboards are discussed. PMID:19192740

Brooke, Joanna S; Annand, John W; Hammer, Angela; Dembkowski, Karen; Shulman, Stanford T

2009-01-01

148

Microbial Surveillance of Potable Water Sources of the International Space Station  

NASA Technical Reports Server (NTRS)

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.

Bruce, Rebekah J.; Ott, C. Mark; Skuratov, Vladimir M.; Pierson, Duane L.

2005-01-01

149

The antibacterial properties of Malaysian tualang honey against wound and enteric microorganisms in comparison to manuka honey  

PubMed Central

Background Antibiotic resistance of bacteria is on the rise, thus the discovery of alternative therapeutic agents is urgently needed. Honey possesses therapeutic potential, including wound healing properties and antimicrobial activity. Although the antimicrobial activity of honey has been effectively established against an extensive spectrum of microorganisms, it differs depending on the type of honey. To date, no extensive studies of the antibacterial properties of tualang (Koompassia excelsa) honey on wound and enteric microorganisms have been conducted. The objectives of this study were to conduct such studies and to compare the antibacterial activity of tualang honey with that of manuka honey. Methods Using a broth dilution method, the antibacterial activity of tualang honey against 13 wound and enteric microorganisms was determined; manuka honey was used as the control. Different concentrations of honey [6.25-25% (w/v)] were tested against each type of microorganism. Briefly, two-fold dilutions of honey solutions were tested to determine the minimum inhibitory concentration (MIC) against each type of microorganism, followed by more assays within a narrower dilution range to obtain more precise MIC values. MICs were determined by both visual inspection and spectrophotometric assay at 620 nm. Minimum bactericidal concentration (MBC) also was determined by culturing on blood agar plates. Results By visual inspection, the MICs of tualang honey ranged from 8.75% to 25% compared to manuka honey (8.75-20%). Spectrophotometric readings of at least 95% inhibition yielded MIC values ranging between 10% and 25% for both types of honey. The lowest MBC for tualang honey was 20%, whereas that for manuka honey was 11.25% for the microorganisms tested. The lowest MIC value (8.75%) for both types of honey was against Stenotrophomonas maltophilia. Tualang honey had a lower MIC (11.25%) against Acinetobacter baumannii compared to manuka honey (12.5%). Conclusion Tualang honey exhibited variable activities against different microorganisms, but they were within the same range as those for manuka honey. This result suggests that tualang honey could potentially be used as an alternative therapeutic agent against certain microorganisms, particularly A. baumannii and S. maltophilia. PMID:19754926

Tan, Hern Tze; Rahman, Rosliza Abdul; Gan, Siew Hua; Halim, Ahmad Sukari; Hassan, Siti Asma'; Sulaiman, Siti Amrah; BS, Kirnpal-Kaur

2009-01-01

150

Specific and Functional Diversity of Endophytic Bacteria from Pine Wood Nematode Bursaphelenchus Xylophilus with Different Virulence  

PubMed Central

Pine wilt disease (PWD) caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus, is one of the most devastating diseases of Pinus spp. The PWN was therefore listed as one of the most dangerous forest pests in China meriting quarantine. Virulence of the PWN is closely linked with the spread of PWD. However, main factors responsible for the virulence of PWNs are still unclear. Recently epiphytic bacteria carried by PWNs have drawn much attention. But little is known about the relationship between endophytic bacteria and virulence of B. xylophilus. In this research, virulence of ten strains of B. xylophilus from different geographical areas in six provinces of China and four pine species were tested with 2-year-old seedlings of Pinus thunbergii. Endophytic bacteria were isolated from PWNs with different virulence to investigate the relationship between the bacteria and PWN virulence. Meanwhile, the carbon metabolism of endophytic bacteria from highly and low virulent B. xylophilus was analyzed using Biolog plates (ECO). The results indicated that ten strains of PWNs showed a wide range of virulence. Simultaneously, endophytic bacteria were isolated from 90% of the B. xylophilus strains. The dominant endophytic bacteria in the nematodes were identified as species of Stenotrophomonas, Achromobacter, Ewingella, Leifsonia, Rhizobium, and Pseudomonas using molecular and biochemical methods. Moreover, S. maltophilia, and A. xylosoxidans subsp. xylosoxidans were the predominant strains. Most of the strains (80%) from P. massoniana contained either S. maltophilia, A. xylosoxidans, or both species. There was a difference between the abilities of the endophytic bacteria to utilize carbon sources. Endophytic bacteria from highly virulent B. xylophilus had a relatively high utilization rate of carbohydrate and carboxylic acids, while bacteria from low virulent B. xylophilus made better use of amino acids. In conclusion, endophytic bacteria widely exist in B. xylophilus from different pines and areas; and B. xylophilus strains with different virulence possessed various endophytic bacteria and diverse carbon metabolism which suggested that the endophytic bacteria species and carbon metabolism might be related with the B. xylophilus virulence. PMID:23289015

Wu, Xiao-Qin; Yuan, Wei-Min; Tian, Xiao-Jing; Fan, Ben; Fang, Xin; Ye, Jian-Ren; Ding, Xiao-Lei

2013-01-01

151

Rapid screening and cultivation of oleaginous microorganisms.  

PubMed

Oleaginous microbial strains were cultivated to identify the best oil-producing strain amongst Yarrowia lipolytica (CGMCC 2.1398), Lipomyces starkeyi (CGMCC 2.1608), Rhodosporidium toruloides (CGMCC 2.1389), Mortierella isabellina (CGMCC 3.3410), Cunninghamella blakeleana (CGMCC 3.970), and Mycobacterium QJ311. A method for rapid determination of oil content and fatty acid composition was established to identify the optimum oil-producing strains. This method had a relative standard deviation of 4.09%, an average recovery ratio of 97.09% and a detection limit of 0.1-1.0 g. Mortierella isabellina CGMCC 3.3410 was identified as the best oil-producing strain amongst the six strains tested, with a total biomass of 75 g/10 L and a lipid content of 35%. A rapid screening method of oleaginous microorganisms is discussed for the first time. PMID:22611917

Gao, Xinlei; Liu, Ye; Che, Zhongju; Wu, Li

2012-04-01

152

Prevalence and Features of Pathogenic Bacteria in the Department of Hematology without Bone Marrow Transplantation in Peking Union Medical College Hospital from 2010 to 2012.  

PubMed

Objective To investigate the incidence,pathogens,and clinical features of infection in consecutive cases from 2010 to 2012 in Peking Union Medical College Hospital. Method The incidence,pathogen,treatment,and outcomes of patients with hematological diseases who had positive findings of bacterium in their samples from 2010 to 2012 were retrospectively analyzed. Results There were 449 positive samples (5.8%) from 4 890 patients during this period,among which 388 were proved to be with pathogenic bacteria. Samples separated from patients with community-aquired infections accounted for 8.4% of all positive samples. Most community-aquired infections were caused by Gram-negative bacteria (75%),although no multidrug-resistant bacteria was observed. Samples separated from patients with nosocomial infections accounted for 91.6% of all positive samples. Respiratory tract (49.4%) and peripheral blood (32.6%) were the most common samples with positive results. Skin soft tissues (10.4%),and urine (3.7%) were less common samples. Most of the pathogenic bacteria of the nosocomial infections were Gram-negative (66.9%). The most common Gram-negative bacteria included Escherichia coli (13.8%),Pseudomonas aeruginosa (12.1%),and Klebsiella pneumonia (12.1%),while Staphylococcus aureus (10.4%),Enterococcus faecium (7.0%),and Staphylococcus epidermidis (5.1%) were the most common Gram-positive bacteria. Gram-negative bacteria consisted of most of sputum samples and peripheral blood samples. Samples from the surface of skin wound and anal swab were composed largely by Gram-positive bacteria (63.8%). The detection rates of extended-spectrum beta-lactamase-producing Klebsiella pneumonia/Klebsiella oxytoca,Escherichia coli,and Proteus mirabilis were 24.0%,87.9% and 38.4%,respectively. The resistance to Acinetobacter baumannii was serious. Multidrug-resistant,extensive drug resistant and pan drug resistant A. baumannii acountted for 74% of all A. Baumannii infections. Stenotrophomonas maltophilia showed low resistance to sulfamethoxazole/trimethoprim,levofloxacin and minocycline. Also,22 methicillin-resistant Staphylococcus aureus and 9 methicillin-resistant Staphylococcus Epidermidis were detected,which were only sensitive to vancomycin,teicoplanin,and linezolid. All patients were treated in the haematology wards and most of them were under agranulocytosis or immunosuppression. Finally,22 patients reached clinical recovery through anti-infective therapy,whereas 49 patients died. Among those deaths,42 patients attributed to severe infections and infection-associated complications. Fourteen of all the deaths might be infected with drug-resistance bacteria. There were 61 samples proved to be bacteria colonization. Nonfermenters such as Acinetobacter baumannii and Stenotrophomonas maltophilia made up for a large amount of bacteria colonization. Conclusions The pathogens of nosocomial infections in the hematology ward are mainly Gram-negative bacteria. The incidences and pathogens vary from different infection sites. Nosocomial infection still has a higher mortality rate. Once nonfermenters are detected positive,the pathogenic or colonial bacteria should be distinguished. PMID:25176215

Lu, Wang; Chen, Yang; Qian, Zhang; Bing, Han; Jun-Ling, Zhuang; Miao, Chen; Nong, Zou; Jian, Li; Ming-Hui, Duan; Wei, Zhang; Tie-Nan, Zhu; Ying, Xu; Shu-Jie, Wang; Dao-Bin, Zhou; Yong-Qiang, Zhao; Hui, Zhang; Peng, Wang; Ying-Chun, Xu

2014-08-31

153

Molecular investigation of bacterial communities on the inner and outer surfaces of peripheral venous catheters.  

PubMed

Peripheral venous catheters (PVCs) are some of the most widely used medical devices in hospitals worldwide. PVC-related infections increase morbidity and treatment costs. The inner surfaces of PVCs are rarely examined for the population structure of bacteria, as it is generally believed that bacteria at this niche are similar to those on the external surface of PVCs. We primarily test this hypothesis and also study the effect of antibiotic treatment on bacterial communities from PVC surfaces. The inner and outer surfaces of PVCs from 15 patients were examined by 454 GS FLX Titanium 16S rRNA sequencing and the culture method. None of the PVCs were colonised according to the culture method and none of the patients had a bacteraemia. From a total of 127,536 high-quality sequence reads, 14 bacterial phyla and 268 diverse bacterial genera were detected. The number of operational taxonomic units for each sample was in the range of 86-157, even though 60 % of patients had received antibiotic treatment. Stenotrophomonas maltophilia was the predominant bacterial species in all the examined PVC samples. There were noticeable but not statistically significant differences between the inner and outer surfaces of PVCs in terms of the distribution of the taxonomic groups. In addition, the bacterial communities on PVCs from antibiotic-treated patients were significantly different from untreated patients. In conclusion, the surfaces of PVCs display complex bacterial communities. Although their significance has yet to be determined, these findings alter our perception of PVC-related infections. PMID:23529345

Zhang, L; Morrison, M; Nimmo, G R; Sriprakash, K S; Mondot, S; Gowardman, J R; George, N; Marsh, N; Rickard, C M

2013-08-01

154

Microbiological investigation of Raphanus sativus L. grown hydroponically in nutrient solutions contaminated with spoilage and pathogenic bacteria.  

PubMed

The survival of eight undesired (spoilage/pathogenic) food related bacteria (Citrobacter freundii PSS60, Enterobacter spp. PSS11, Escherichia coli PSS2, Klebsiella oxytoca PSS82, Serratia grimesii PSS72, Pseudomonas putida PSS21, Stenotrophomonas maltophilia PSS52 and Listeria monocytogenes ATCC 19114(T)) was investigated in mineral nutrient solution (MNS) during the crop cycle of radishes (Raphanus sativus L.) cultivated in hydroponics in a greenhouse. MNSs were microbiologically analyzed weekly by plate count. The evolution of the pure cultures was also evaluated in sterile MNS in test tubes. The inoculated trials contained an initial total mesophilic count (TMC) ranging between 6.69 and 7.78Log CFU/mL, while non-sterile and sterile control trials showed levels of 4.39 and 0.97Log CFU/mL, respectively. In general, all inoculated trials showed similar levels of TMC in MNS during the experimentation, even though the levels of the inoculated bacteria decreased. The presence of the inoculums was ascertained by randomly amplified polymorphic DNA (RAPD) analysis applied on the isolates collected at 7-day intervals. At harvest, MNSs were also analyzed by denaturing gradient gel electrophoresis (DGGE). The last analysis, except P. putida PSS21 in the corresponding trial, did not detect the other bacteria, but confirmed that pseudomonads were present in un-inoculated MNSs. Despite the high counts detected (6.44 and 7.24CFU/g), only C. freundii PSS60, Enterobacter spp. PSS11 and K. oxytoca PSS82 were detected in radishes in a living form, suggesting their internalization. PMID:23290244

Settanni, Luca; Miceli, Alessandro; Francesca, Nicola; Cruciata, Margherita; Moschetti, Giancarlo

2013-01-01

155

Microbe associated molecular patterns from rhizosphere bacteria trigger germination and Papaver somniferum metabolism under greenhouse conditions.  

PubMed

Ten PGPR from different backgrounds were assayed on Papaver somniferum var. Madrigal to evaluate their potential as biotic elicitors to increase alkaloid content under the rationale that some microbe associated molecular patterns (MAMPs) are able to trigger plant metabolism. First, the 10 strains and their culture media at two different concentrations were tested for their ability to trigger seed germination. Then, the best three strains were tested for their ability to increase seedling growth and alkaloid levels under greenhouse conditions. Only three strains and their culture media enhanced germination. Then, germination enhancing capacity of these best three strains, N5.18 Stenotrophomonas maltophilia, Aur9 Chryseobacterium balustinum and N21.4 Pseudomonas fluorescens was evaluated in soil. Finally, the three strains were applied on seedlings at two time points, by soil drench or by foliar spray. Photosynthesis was measured, plant height was recorded, capsules were weighted and alkaloids analyzed by HPLC. Only N5.18 delivered by foliar spray significantly increased plant height coupled to an increase in total alkaloids and a significant increase in opium poppy straw dry weight; these increases were supported by a better photosynthetic efficiency. The relative contents of morphine, thebaine, codeine and oripavine were affected by this treatment causing a significant increase in morphine coupled to a decrease in thebaine, demonstrating the effectivity of MAMPs from N5.18 in this plant species. Considering the increase in capsule biomass and alkaloids together with the acceleration of germination, strain N5.18 appears as a good candidate to elicit plant metabolism and consequently, to increase productivity of Papaver somniferum. PMID:24296249

Bonilla, A; Sarria, A L F; Algar, E; Muñoz Ledesma, F J; Ramos Solano, B; Fernandes, J B; Gutierrez Mañero, F J

2014-01-01

156

Biosynthesis and structural characterization of silver nanoparticles from bacterial isolates  

SciTech Connect

Graphical abstract: In this study five bacterial isolates belong to different genera were found to be able to biosynthesize silver nanoparticles. Biosynthesis and spectral characterization are reported here. Highlights: {yields} About 300 bacterial isolates were screened for their ability to produce nanosilvers {yields} Five of them were potential candidates for synthesis of silver nanoparticles {yields} Production of silver nanoparticles was examined using UV-Vis, XRD, SEM and EDS. {yields} The presence of nanoparticles with all five bacterial isolates was confirmed. -- Abstract: This study aimed to develop a green process for biosynthesis of silver nanomaterials by some Egyptian bacterial isolates. This target was achieved by screening an in-house culture collection consists of 300 bacterial isolates for silver nanoparticle formation. Through screening process, it was observed that strains belonging to Escherichia coli (S30, S78), Bacillus megaterium (S52), Acinetobacter sp. (S7) and Stenotrophomonas maltophilia (S54) were potential candidates for synthesis of silver nanoparticles. The extracellular production of silver nanoparticles by positive isolates was investigated by UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results demonstrated that UV-visible spectrum of the aqueous medium containing silver ion showed a peak at 420 nm corresponding to the plasmon absorbance of silver nanoparticles. Scanning electron microscopy micrograph showed formation of silver nanoparticles in the range of 15-50 nm. XRD-spectrum of the silver nanoparticles exhibited 2{theta} values corresponding to the silver nanocrystal that produce in hexagonal and cubic crystal configurations with different plane of orientation. In addition, the signals of the silver atoms were observed by EDS-spectrum analysis that confirms the presence of silver nanoparticles (AgNPs) in all positive bacterial isolates.

Zaki, Sahar, E-mail: saharzaki@yahoo.com [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt)] [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt); El Kady, M.F. [Fabrication Technology Department, Advanced Technology and New Materials Research Institute (ATNMRI), Mubarak City for Scientific Research and Technology Applications, Alexandria (Egypt)] [Fabrication Technology Department, Advanced Technology and New Materials Research Institute (ATNMRI), Mubarak City for Scientific Research and Technology Applications, Alexandria (Egypt); Abd-El-Haleem, Desouky [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt)] [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt)

2011-10-15

157

Influence of Referral Bias on the Clinical Characteristics of Patients with Gram-Negative Bloodstream Infection  

PubMed Central

Summary Referral bias can influence the results of studies performed at tertiary-care centers. In this study, we evaluated demographic and microbiologic factors that influenced referral of patients with gram-negative bloodstream infection (BSI). We identified 2919 and 846 unique patients with gram-negative BSI in a referral cohort of patients treated at Mayo Clinic Hospitals and a population-based cohort of Olmsted County, Minnesota, residents between 1/1/1998 and 12/31/2007, respectively. Multivariable logistic regression analysis was used to determine factors associated with referral. Elderly patients aged ? 80 years with gram-negative BSI were less likely to be referred than younger patients (odds ratio [OR]=0.43, 95% confidence intervals [CI]: 0.30-0.62) as were females (OR=0.63, 95% CI: 0.53-0.74). After adjusting for age and gender, bloodstream isolates of Escherichia coli (OR=0.50, 95% CI: 0.43-0.58) and Proteus mirabilis (OR=0.49, 95% CI: 0.30-0.82) were underrepresented in the referral cohort; and Pseudomonas aeruginosa (OR=2.26, 95% CI: 1.70-3.06), Enterobacter cloacae (OR=2.31, 95% CI: 1.53-3.66), Serratia marcescens (OR=2.34, 95% CI: 1.33-4.52) and Stenotrophomonas maltophilia (OR=17.94, 95% CI: 3.98-314.43) were overrepresented in the referral cohort. We demonstrated that demographic and microbiologic characteristics of patients with gram-negative BSI had an influence on referral patterns. These factors should be considered when interpreting results of investigations performed at tertiary-care centers. PMID:21281552

Al-Hasan, M. N.; Eckel-Passow, J. E.; Baddour, L. M.

2011-01-01

158

Identification of a Series of Tricyclic Natural Products as Potent Broad-Spectrum Inhibitors of Metallo-?-Lactamases  

PubMed Central

This work describes the discovery and characterization of a novel series of tricyclic natural product-derived metallo-?-lactamase inhibitors. Natural product screening of the Bacillus cereus II enzyme identified an extract from a strain of Chaetomium funicola with inhibitory activity against metallo-?-lactamases. SB236050, SB238569, and SB236049 were successfully extracted and purified from this extract. The most active of these compounds was SB238569, which possessed Ki values of 79, 17, and 3.4 ?M for the Bacillus cereus II, Pseudomonas aeruginosa IMP-1, and Bacteroides fragilis CfiA metallo-?-lactamases, respectively, yet none of the compounds exhibited any inhibitory activity against the Stenotrophomonas maltophilia L-1 metallo-?-lactamase (50% inhibitory concentration > 1,000 ?M). The lack of activity against angiotensin-converting enzyme and serine ?-lactamases demonstrated the selective nature of these compounds. The crystal structure of SB236050 complexed in the active site of CfiA has been obtained to a resolution of 2.5 Å. SB236050 exhibits key polar interactions with Lys184, Asn193, and His162 and a stacking interaction with the indole ring of Trp49 in the flap, which is in the closed conformation over the active site groove. SB236050 and SB238569 also demonstrate good antibacterial synergy with meropenem. Eight micrograms of SB236050 per ml gave rise to an eightfold drop in the MIC of meropenem for two clinical isolates of B. fragilis producing CfiA, making these strains sensitive to meropenem (MIC ? 4 ?g/ml). Consequently, this series of metallo-?-lactamase inhibitors exhibit the most promising antibacterial synergy activity so far observed against organisms producing metallo-?-lactamases. PMID:12019104

Payne, David J.; Hueso-Rodriguez, Juan Antonio; Boyd, Helen; Concha, Nestor O.; Janson, Cheryl A.; Gilpin, Martin; Bateson, John H.; Cheever, Christy; Niconovich, Nancy L.; Pearson, Stewart; Rittenhouse, Stephen; Tew, David; Diez, Emilio; Perez, Paloma; de la Fuente, Jesus; Rees, Michael; Rivera-Sagredo, Alfonso

2002-01-01

159

Evaluation of a new monochloramine generation system for controlling legionella in building hot water systems.  

PubMed

Objective.?To evaluate the efficacy of a new monochloramine generation system for control of Legionella in a hospital hot water distribution system. Setting.?A 495-bed tertiary care hospital in Pittsburgh, Pennsylvania. The hospital has 12 floors covering approximately 78,000 m(2). Methods.?The hospital hot water system was monitored for a total of 29 months, including a 5-month baseline sampling period prior to installation of the monochloramine system and 24 months of surveillance after system installation (postdisinfection period). Water samples were collected for microbiological analysis (Legionella species, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Acinetobacter species, nitrifying bacteria, heterotrophic plate count [HPC] bacteria, and nontuberculous mycobacteria). Chemical parameters monitored during the investigation included monochloramine, chlorine (free and total), nitrate, nitrite, total ammonia, copper, silver, lead, and pH. Results.?A significant reduction in Legionella distal site positivity was observed between the pre- and postdisinfection periods, with positivity decreasing from an average of 53% (baseline) to an average of 9% after monochloramine application ([Formula: see text]). Although geometric mean HPC concentrations decreased by approximately 2 log colony-forming units per milliliter during monochloramine treatment, we did not observe significant changes in other microbial populations. Conclusions.?This is the first evaluation in the United States of a commercially available monochloramine system installed on a hospital hot water system for Legionella disinfection, and it demonstrated a significant reduction in Legionella colonization. Significant increases in microbial populations or other negative effects previously associated with monochloramine use in large municipal cold water systems were not observed. PMID:25333430

Duda, Scott; Kandiah, Sheena; Stout, Janet E; Baron, Julianne L; Yassin, Mohamed; Fabrizio, Marie; Ferrelli, Juliet; Hariri, Rahman; Wagener, Marilyn M; Goepfert, John; Bond, James; Hannigan, Joseph; Rogers, Denzil

2014-11-01

160

Convenient test using a combination of chelating agents for detection of metallo-beta-lactamases in the clinical laboratory.  

PubMed

Although transmissible metallo-beta-lactamases (MBLs) are a serious threat to beta-lactam antibiotic therapy, the CLSI currently does not recommend testing methods for the detection of MBLs. The aim of this study was to evaluate the capability of double-disk tests (DDTs) by using disks containing a combination of the chelators 2-mercaptopropionic acid (MPA) and Tris-EDTA (TE) to detect MBLs. Sixteen isolates (4 Acinetobacter baumannii isolates, 6 Pseudomonas aeruginosa isolates, 1 Serratia marcescens isolate, 1 Aeromonas hydrophila isolate, 1 Aeromonas veronii isolate, 2 Chryseobacterium meningosepticum isolates, and 1 Stenotrophomonas maltophilia isolate) producing IMP-1, IMP-1-like, IMP-18, GIM-1, SPM-1, VIM-2, VIM-2-like, and chromosomal MBLs and 20 isolates (7 Klebsiella pneumoniae isolates, 3 Escherichia coli isolates, 5 Enterobacter cloacae isolates, 2 S. marcescens isolates, 1 Proteus mirabilis isolate, and 2 A. baumannii isolates) producing non-MBL carbapenemases, AmpC beta-lactamases, and extended-spectrum beta-lactamases were tested. The DDT method was evaluated by using four types of chelator disks (TE, high-strength TE, MPA, and TE plus 20 microl of MPA [at various concentrations]) and the beta-lactams imipenem (IPM), meropenem (MEM), ertapenem (ERT), and ceftazidime (CAZ). DDTs with IPM and a TE disk supplemented with 1:320 MPA detected all MBLs and yielded no false-positive results. Some, but not all, MBL producers were detected in IPM-based tests involving the single chelator TE or MPA alone or by ERT- or CAZ-based tests. IPM-based tests with MPA concentrations other than 1:320 and all MEM-based tests had suboptimal sensitivities or specificities. DDT with IPM and a TE disk supplemented with 20 microl of 1:320 MPA appears to be convenient for the detection of MBLs in the clinical laboratory. PMID:17596358

Kim, Soo-Young; Hong, Seong Geun; Moland, Ellen S; Thomson, Kenneth S

2007-09-01

161

Novel Cyclic di-GMP Effectors of the YajQ Protein Family Control Bacterial Virulence  

PubMed Central

Bis-(3?,5?) cyclic di-guanylate (cyclic di-GMP) is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc). This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (Kd?2 µM). Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence. PMID:25329577

An, Shi-qi; Caly, Delphine L.; McCarthy, Yvonne; Murdoch, Sarah L.; Ward, Joseph; Febrer, Melanie; Dow, J. Maxwell; Ryan, Robert P.

2014-01-01

162

Evaluation of Microorganisms Cultured from Injured and Repressed Tissue Regeneration Sites in Endangered Giant Aquatic Ozark Hellbender Salamanders  

PubMed Central

Investigation into the causes underlying the rapid, global amphibian decline provides critical insight into the effects of changing ecosystems. Hypothesized and confirmed links between amphibian declines, disease, and environmental changes are increasingly represented in published literature. However, there are few long-term amphibian studies that include data on population size, abnormality/injury rates, disease, and habitat variables to adequately assess changes through time. We cultured and identified microorganisms isolated from abnormal/injured and repressed tissue regeneration sites of the endangered Ozark Hellbender, Cryptobranchus alleganiensis bishopi, to discover potential causative agents responsible for their significant decline in health and population. This organism and our study site were chosen because the population and habitat of C. a. bishopi have been intensively studied from 1969–2009, and the abnormality/injury rate and apparent lack of regeneration were established. Although many bacterial and fungal isolates recovered were common environmental organisms, several opportunistic pathogens were identified in association with only the injured tissues of C.a. bishopi. Bacterial isolates included Aeromonas hydrophila, a known amphibian pathogen, Granulicetella adiacens, Gordonai terrae, Stenotrophomonas maltophilia, Aerococcus viridans, Streptococcus pneumoniae and a variety of Pseudomonads, including Pseudomonas aeruginosa, P. stutzeri, and P. alcaligenes. Fungal isolates included species in the genera Penicillium, Acremonium, Cladosporium, Curvularia, Fusarium, Streptomycetes, and the Class Hyphomycetes. Many of the opportunistic pathogens identified are known to form biofilms. Lack of isolation of the same organism from all wounds suggests that the etiological agent responsible for the damage to C. a. bishopi may not be a single organism. To our knowledge, this is the first study to profile the external microbial consortia cultured from a Cryptobranchid salamander. The incidence of abnormalities/injury and retarded regeneration in C. a. bishopi may have many contributing factors including disease and habitat degradation. Results from this study may provide insight into other amphibian population declines. PMID:22205979

Nickerson, Cheryl A.; Ott, C. Mark; Castro, Sarah L.; Garcia, Veronica M.; Molina, Thomas C.; Briggler, Jeffrey T.; Pitt, Amber L.; Tavano, Joseph J.; Byram, J. Kelly; Barrila, Jennifer; Nickerson, Max A.

2011-01-01

163

In vitro activity of the tricyclic beta-lactam GV104326.  

PubMed Central

GV104326 is a novel tricyclic beta-lactam (a trinem or, formerly, tribactam). The in vitro activity of GV104326 was compared with those of cefuroxime, cefixime, amoxicillin, amoxicillin-clavulanic acid, cefpirome, and ciprofloxacin. GV104326 had in vitro activity generally similar to that of cefixime against members of the family Enterobacteriaceae (MIC at which 90% of the isolates are inhibited [MIC90], < or = 2 micrograms/ml), with cefuroxime and amoxicillin-clavulanic acid being 8- to 32-fold less active and with cefpirome being 4- to 8-fold more active against members of this family. The trinem had no activity against Pseudomonas aeruginosa or Stenotrophomonas maltophilia (MIC90, > 128 micrograms/ml) but was the most active agent against Acinetobacter calcoaceticus. GV104326 was particularly active against gram-positive cocci. Ninety percent of methicillin-susceptible Staphylococcus aureus strains were susceptible to 0.03 microgram of GV104326 per ml, making it the most active agent studied. Enterococci and Lancefield group A and B streptococci were generally equally or somewhat more susceptible to GV104326 than they were to amoxicillin. Streptococcus pneumoniae strains were highly susceptible to GV104326, and those strains which showed decreased susceptibility to penicillin were generally twofold more susceptible to the trinem than to amoxicillin. Haemophilus influenzae and Moraxella catarrhalis were highly susceptible to GV104326 (MIC90s, 0.12 and 0.03 microgram/ml, respectively). The anaerobes Clostridium perfringens, Bacteroides fragilis, and Peptostreptococcus spp. were more susceptible to the trinems (formerly tribactams) than to the other agents studied. PMID:8723475

Wise, R; Andrews, J M; Brenwald, N

1996-01-01

164

Exploring nicotinamide cofactor promiscuity in NAD(P)H-dependent flavin containing monooxygenases (FMOs) using natural variation within the phosphate binding loop. Structure and activity of FMOs from Cellvibrio sp. BR and Pseudomonas stutzeri NF13  

PubMed Central

Flavin-containing monooxygenases (FMOs) catalyse asymmetric oxidation reactions that have potential for preparative organic synthesis, but most use the more expensive, phosphorylated nicotinamide cofactor NADPH to reduce FAD to FADH2 prior to formation of the (hydro)peroxy intermediate required for substrate oxygenation. A comparison of the structures of NADPH-dependent FMO from Methylophaga aminisulfidivorans (mFMO) and SMFMO from Stenotrophomonas maltophilia, which is able to use both NADPH and NADH, suggested that the promiscuity of the latter enzyme may be due in part to the substitution of an Arg–Thr couple in the NADPH phosphate recognition site in mFMO, for a Gln–His couple in SMFMO (Jensen et al., 2012, Chembiochem, 13, 872–878). Natural variation within the phosphate binding region, and its influence on nicotinamide cofactor promiscuity, was explored through the cloning, expression, characterisation and structural studies of FMOs from Cellvibrio sp. BR (CFMO) and Pseudomonas stutzeri NF13 (PSFMO), which possess Thr–Ser and Gln–Glu in the putative phosphate recognition positions, respectively. CFMO and PSFMO displayed 5- and 1.5-fold greater activity, respectively, than SMFMO for the reduction of FAD with NADH, and were also cofactor promiscuous, displaying a ratio of activity with NADH:NADPH of 1.7:1 and 1:1.3, respectively. The structures of CFMO and PSFMO revealed the context of the phosphate binding loop in each case, and also clarified the structure of the mobile helix–loop–helix motif that appears to shield the FAD-binding pocket from bulk solvent in this class of FMOs, a feature that was absent from the structure of SMFMO. PMID:25383040

Jensen, Chantel N.; Ali, Sohail T.; Allen, Michael J.; Grogan, Gideon

2014-01-01

165

Microbial biofilms on the sandstone monuments of the Angkor Wat Complex, Cambodia.  

PubMed

Discoloring biofilms from Cambodian temples Angkor Wat, Preah Khan, and the Bayon and West Prasat in Angkor Thom contained a microbial community dominated by coccoid cyanobacteria. Molecular analysis identified Chroococcidiopsis as major colonizer, but low similarity values (<95%) suggested a similar genus or species not present in the databases. In only two of the six sites sampled were filamentous cyanobacteria, Microcoleus, Leptolyngbya, and Scytonema, found; the first two detected by sequencing of 16S rRNA gene library clones from samples of a moist green biofilm on internal walls in Preah Khan, where Lyngbya (possibly synonymous with Microcoleus) was seen by direct microscopy as major colonizer. Scytonema was detected also by microscopy on an internal wall in the Bayon. This suggests that filamentous cyanobacteria are more prevalent in internal (high moisture) areas. Heterotrophic bacteria were found in all samples. DNA sequencing of bands from DGGE gels identified Proteobacteria (Stenotrophomonas maltophilia and Methylobacterium radiotolerans) and Firmicutes (Bacillus sp., Bacillus niacini, Bacillus sporothermodurans, Lysinibacillus fusiformis, Paenibacillus sp., Paenibacillus panacisoli, and Paenibacillus zanthoxyli). Some of these bacteria produce organic acids, potentially degrading stone. Actinobacteria, mainly streptomycetes, were present in most samples; algae and fungi were rare. A dark-pigmented filamentous fungus was detected in internal and external Preah Khan samples, while the alga Trentepohlia was found only in samples taken from external, pink-stained stone at Preah Khan. Results show that these microbial biofilms are mature communities whose major constituents are resistant to dehydration and high levels of irradiation and can be involved in deterioration of sandstone. Such analyses are important prerequisites to the application of control strategies. PMID:22006074

Gaylarde, Christine C; Rodríguez, César Hernández; Navarro-Noya, Yendi E; Ortega-Morales, B Otto

2012-02-01

166

Evaluation of microorganisms cultured from injured and repressed tissue regeneration sites in endangered giant aquatic Ozark Hellbender salamanders.  

PubMed

Investigation into the causes underlying the rapid, global amphibian decline provides critical insight into the effects of changing ecosystems. Hypothesized and confirmed links between amphibian declines, disease, and environmental changes are increasingly represented in published literature. However, there are few long-term amphibian studies that include data on population size, abnormality/injury rates, disease, and habitat variables to adequately assess changes through time. We cultured and identified microorganisms isolated from abnormal/injured and repressed tissue regeneration sites of the endangered Ozark Hellbender, Cryptobranchus alleganiensis bishopi, to discover potential causative agents responsible for their significant decline in health and population. This organism and our study site were chosen because the population and habitat of C. a. bishopi have been intensively studied from 1969-2009, and the abnormality/injury rate and apparent lack of regeneration were established. Although many bacterial and fungal isolates recovered were common environmental organisms, several opportunistic pathogens were identified in association with only the injured tissues of C.a. bishopi. Bacterial isolates included Aeromonas hydrophila, a known amphibian pathogen, Granulicetella adiacens, Gordonai terrae, Stenotrophomonas maltophilia, Aerococcus viridans, Streptococcus pneumoniae and a variety of Pseudomonads, including Pseudomonas aeruginosa, P. stutzeri, and P. alcaligenes. Fungal isolates included species in the genera Penicillium, Acremonium, Cladosporium, Curvularia, Fusarium, Streptomycetes, and the Class Hyphomycetes. Many of the opportunistic pathogens identified are known to form biofilms. Lack of isolation of the same organism from all wounds suggests that the etiological agent responsible for the damage to C. a. bishopi may not be a single organism. To our knowledge, this is the first study to profile the external microbial consortia cultured from a Cryptobranchid salamander. The incidence of abnormalities/injury and retarded regeneration in C. a. bishopi may have many contributing factors including disease and habitat degradation. Results from this study may provide insight into other amphibian population declines. PMID:22205979

Nickerson, Cheryl A; Ott, C Mark; Castro, Sarah L; Garcia, Veronica M; Molina, Thomas C; Briggler, Jeffrey T; Pitt, Amber L; Tavano, Joseph J; Byram, J Kelly; Barrila, Jennifer; Nickerson, Max A

2011-01-01

167

Air-dust-borne associations of phototrophic and hydrocarbon-utilizing microorganisms: promising consortia in volatile hydrocarbon bioremediation.  

PubMed

Aquatic and terrestrial associations of phototrophic and heterotrophic microorganisms active in hydrocarbon bioremediation have been described earlier. The question arises: do similar consortia also occur in the atmosphere? Dust samples at the height of 15 m were collected from Kuwait City air, and analyzed microbiologically for phototrophic and heterotrophic hydrocarbon-utilizing microorganisms, which were subsequently characterized according to their 16S rRNA gene sequences. The hydrocarbon utilization potential of the heterotrophs alone, and in association with the phototrophic partners, was measured quantitatively. The chlorophyte Gloeotila sp. and the two cyanobacteria Nostoc commune and Leptolyngbya thermalis were found associated with dust, and (for comparison) the cynobacteria Leptolyngbya sp. and Acaryochloris sp. were isolated from coastal water. All phototrophic cultures harbored oil vapor-utilizing bacteria in the magnitude of 10(5) g(-1). Each phototrophic culture had its unique oil-utilizing bacteria; however, the bacterial composition in Leptolyngbya cultures from air and water was similar. The hydrocarbon-utilizing bacteria were affiliated with Acinetobacter sp., Aeromonas caviae, Alcanivorax jadensis, Bacillus asahii, Bacillus pumilus, Marinobacter aquaeolei, Paenibacillus sp., and Stenotrophomonas maltophilia. The nonaxenic cultures, when used as inocula in batch cultures, attenuated crude oil in light and dark, and in the presence of antibiotics and absence of nitrogenous compounds. Aqueous and diethyl ether extracts from the phototrophic cultures enhanced the growth of the pertinent oil-utilizing bacteria in batch cultures, with oil vapor as a sole carbon source. It was concluded that the airborne microbial associations may be effective in bioremediating atmospheric hydrocarbon pollutants in situ. Like the aquatic and terrestrial habitats, the atmosphere contains dust-borne associations of phototrophic and heterotrophic hydrocarbon-utilizing bacteria that are active in hydrocarbon attenuation. PMID:22529000

Al-Bader, Dhia; Eliyas, Mohamed; Rayan, Rihab; Radwan, Samir

2012-11-01

168

MALDI-TOF: a useful tool for laboratory identification of uncommon glucose non-fermenting Gram-negative bacteria associated with cystic fibrosis.  

PubMed

The predisposition of patients with cystic fibrosis (CF) for recurrent pulmonary infections can result in poor prognosis of the disease. Although the clinical significance in CF of micro-organisms, such as Staphylococcus aureus, Haemophilus influenzae and Pseudomonas aeruginosa, is well established, the implication of uncommon glucose non-fermenting Gram-negative bacilli (UGNF-GNB) in respiratory samples from CF patients is still unclear. Because of limitations of traditional methods used in most clinical laboratories, the accurate identification of these microbes is a challenge. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) is an alternative tool for efficient identification of bacteria. This was a retrospective study to evaluate different identification methods in a collection of UGNF-GNB isolated from children with CF during a period of three years. The performance of MALDI-TOF was compared to that of 16S rDNA gene sequencing and to a conventional and automated phenotypic identification. The discriminatory power of MALDI-TOF (75.0?% agreement) was superior to automated techniques (67.1?% agreement) and to conventional phenotypical identification (50.0?% agreement). MALDI-TOF also demonstrated high accuracy in identifying Stenotrophomonas maltophilia, Achromobacter xylosoxidans and Chryseobacterium indologenes, but had limited utility in identifying Pandoraea spp. and some species of Acinetobacter and Chryseobacterium (other than C. indologenes). Although MALDI-TOF identified only 75?% of the isolates in comparison with 16S rDNA gene sequencing, the prompt identification and high discriminatory power exhibited by MALDI-TOF make it a useful tool for the characterization of micro-organisms that are difficult to identify using routine methods. PMID:24980571

Homem de Mello de Souza, Helena Aguilar Peres; Dalla-Costa, Libera Maria; Vicenzi, Fernando José; Camargo de Souza, Dilair; Riedi, Carlos Antônio; Filho, Nelson Augusto Rosario; Pilonetto, Marcelo

2014-09-01

169

[Yearly changes in antibacterial activities of cefozopran against various clinical isolates between 1996 and 2000--II. Gram-negative bacteria].  

PubMed

The in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates obtained between 1996 and 2000 were yearly evaluated and compared with those of other cephems, oxacephems, and carbapenems. Thirty-two species 2,697 strains of Gram-negative bacteria were isolated from the clinical materials annually collected from January to December, and consisted of Moraxella subgenus Branhamella catarrhalis (n = 125), Escherichia coli (n = 250), Citrobacter freundii (n = 153), Citrobacter koseri (n = 97), Klebsiella pneumoniae (n = 150), Klebsiella oxytoca (n = 100), Enterobacter aerogenes (n = 50), Enterobacter cloacae (n = 125), Serratia marcescens (n = 153), Proteus mirabillis (n = 103), Proteus vulgaris (n = 77), Morganella morganii (n = 141), Providencia spp. (P. alcalifaciens, P. rettgeri, P. stuartii; n = 154), Pseudomonas aeruginosa (n = 211), Pseudomonas putida (n = 49), Burkholderia cepacia (n = 102), Stenotrophomonas maltophilia (n = 101), Haemophilus influenzae (n = 210), Acinetobactor baumannii (n = 63), Acinetobactor Iwoffii (n = 30), Bacteroides fragilis group (B. fragilis, B. vulgatus, B. distasonis, B. ovatus, B. thetaiotaomicron; n = 129), and Prevotella spp. (P. melaninogenica, P. intermedia, P. bivia, P. oralis, P. denticola; n = 124). CZOP possessed stable antibacterial activities against M. (B.) catarrhalis, E. coli, C. freundii, C. koseri, K. pneumoniae, K. oxytoca, E. aerogenes, E. cloacae, S. marcescens, P. mirabilis, P. vulgaris, M. morganii, Providencia spp., P. aeruginosa, and A. lowffii throughout 5 years. The MIC90 of CZOP against those strains were consistent with those obtained from the studies performed until the new drug application approval. On the other hand, the MIC90 of CZOP against H. influenzae yearly obviously increased with approximately 65-time difference during study period. The MIC90 of cefpirome, cefepime, and flomoxef against H. influenzae also yearly tended to rise. The present results demonstrated that CZOP had maintained the antibacterial activity against almost Gram-negative strains tested. However, the decrease in the antibacterial activity of CZOP against H. influenzae was suggested. PMID:12071094

Suzuki, Yumiko; Nishinari, Chisato; Endo, Harumi; Tamura, Chieko; Jinbo, Keiko; Hiramatsu, Nobuyoshi; Akiyama, Kazumitsu; Koyama, Tsuneo

2002-04-01

170

[Yearly changes in antibacterial activities of cefozopran against various clinical isolates between 1996 and 2001--II. Gram-negative bacteria].  

PubMed

The in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates obtained between 1996 and 2001 were yearly evaluated and compared with those of other cephems, oxacephems and carbapenems. A total of 3,245 strains in 32 species of Gram-negative bacteria were isolated from the clinical materials annually collected from January to December, and consisted of Moraxella subgenus Branhamella catarrhalis, Escherichia coli, Citrobacter freundii, Citrobacter koseri, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae, Serratia marcescens, Proteus mirabillis, Proteus vulgaris, Morganella morganii, Providencia spp. (P. alcalifaciens, P. rettgeri, P. stuartii), Pseudomonas aeruginosa, Pseudomonas putida, Burkholderia cepacia, Stenotrophomonas maltophilia, Haemophilus influenzae, Acinetobactor baumannii, Acinetobactor lwoffii, Bacteroides fragilis group (B. fragilis, B. vulgatus, B. distasonis, B. ovatus, B. thetaiotaomicron), and Prevotella spp. (P. melaninogenica, P. intermedia, P. bivia, P. oralis, P. denticola). CZOP possessed stable antibacterial activities against M. (B.) catarrhalis, E. coli, C. freundii, C. koseri, K. pneumoniae, K. oxytoca, E. aerogenes, E. cloacae, S. marcescens, P. mirabilis, P. vulgaris, M. morganii, Providencia spp., P. aeruginosa, and A. lwoffii throughout 6 years. The MIC90 of CZOP against those strains were consistent with those obtained from the studies performed until the new drug application approval. On the other hand, the MIC90 of CZOP against H. influenzae yearly obviously increased with approximately 64-time difference during the study period. The MIC90 of cefpirome, cefepime, and flomoxef against H. influenzae also yearly tended to rise. The present results demonstrated that CZOP had maintained the antibacterial activity against almost Gram-negative strains tested. However, the decrease in antibacterial activities of CZOP against B. cepacia, and H. influenzae was suggested. PMID:14567255

Suzuki, Yumiko; Nishinari, Chisato; Endo, Harumi; Hiramatsu, Nobuyoshi; Akiyama, Kazumitsu; Koyama, Tsuneo

2003-08-01

171

In vitro and in vivo antibacterial activities of CS-834, a novel oral carbapenem.  

PubMed Central

CS-834 is a novel oral carbapenem antibiotic. This compound is an ester-type prodrug of the active metabolite R-95867. The antibacterial activity of R-95867 was tested against 1,323 clinical isolates of 35 species and was compared with those of oral cephems, i.e., cefteram, cefpodoxime, cefdinir, and cefditoren, and that of a parenteral carbapenem, imipenem. R-95867 exhibited a broad spectrum of activity covering both gram-positive and -negative aerobes and anaerobes. Its activity was superior to those of the other compounds tested against most of the bacterial species tested. R-95867 showed potent antibacterial activity against clinically significant pathogens: methicillin-susceptible Staphylococcus aureus including ofloxacin-resistant strains, Streptococcus pneumoniae including penicillin-resistant strains, Clostridium perfringens, Neisseria spp., Moraxella catarrhalis, most members of the family Enterobacteriaceae, and Haemophilus influenzae (MIC at which 90% of strains are inhibited, < or =0.006 to 0.78 microg/ml). R-95867 was quite stable to hydrolysis by most of the beta-lactamases tested except the metallo-beta-lactamases from Stenotrophomonas maltophilia and Bacteroides fragilis. R-95867 showed potent bactericidal activity against S. aureus and Escherichia coli. Penicillin-binding proteins 1 and 4 of S. aureus and 1Bs, 2, 3, and 4 of E. coli had high affinities for R-95867. The in vivo efficacy of CS-834 was evaluated in murine systemic infections caused by 16 strains of gram-positive and -negative pathogens. The efficacy of CS-834 was in many cases superior to those of cefteram pivoxil, cefpodoxime proxetil, cefdinir, and cefditoren pivoxil, especially against infections caused by S. aureus, penicillin-resistant S. pneumoniae, E. coli, Citrobacter freundii, and Proteus vulgaris. Among the drugs tested, CS-834 showed the highest efficacy against experimental pneumonia in mice caused by penicillin-resistant S. pneumoniae. PMID:9420035

Fukuoka, T; Ohya, S; Utsui, Y; Domon, H; Takenouchi, T; Koga, T; Masuda, N; Kawada, H; Kakuta, M; Kubota, M; Ishii, C; Ishii, C; Sakagawa, E; Harasaki, T; Hirasawa, A; Abe, T; Yasuda, H; Iwata, M; Kuwahara, S

1997-01-01

172

Recent developments in carbapenems.  

PubMed

Carbapenems are beta-lactam antibiotics characterised by the presence of a beta-lactam ring with a carbon instead of sulfone in the 4-position of the thyazolidinic moiety. The first carbapenem to be utilised in therapy was imipenem, the N-formimidoyl derivative of thienamycin. Imipenem is coadministered with cilastatin, an inhibitor of human renal dehydropeptidase I, as imipenem is hydrolysed by this enzyme. Meropenem was the first carbapenem with a 1-beta-methyl group and 2-thio pyrrolidinyl moiety, which renders this antibiotic stable to renal dehydropeptidase I. Other carbapenems for parenteral administration later discovered include biapenem, panipenem, ertapenem, lenapenem, E-1010, S-4661 and BMS-181139. Carbapenems which are orally administered include sanfetrinem, DZ-2640, CS-834 and GV-129606. Carbapenems have an ultra-broad spectrum of antibacterial activity and stability to almost all clinically relevant beta-lactamases. This differentiates them from all other currently available classes of beta-lactam antibiotics. However, Class B beta-lactamases, along with some rare Class A and D enzymes, are able to hydrolyse these antibiotics. Although Class B enzymes are generally chromosomally-encoded (isolated from Stenotrophomonas maltophilia, Aeromonas spp., Bacillus cereus, Bacteroides fragilis, Flavobacterium spp. and Legionella gormanii), plasmid-metallo-beta-lactamases now are appearing in B. fragilis, Pseudomonas aeruginosa, Acinetobacter baumannii and members of Enterobacteriaceae such as Serratia marcescens and Klebsiella pneumoniae. The number of these enzymes compared to the number of other beta-lactamase types is still low, however, it is likely that they will spread due to the increased selective pressure of carbapenem use. The very broad spectrum of antimicrobial activity associated with a good clinical efficacy and a favourable safety profile makes the carbapenems valuable as 'first-line' antibiotics in initial empirical therapy for the treatment of severe infections. PMID:11922861

Bonfiglio, Giovanni; Russo, Giovanni; Nicoletti, Giuseppe

2002-04-01

173

In vitro and in vivo antibacterial activities of CS-834, a novel oral carbapenem.  

PubMed

CS-834 is a novel oral carbapenem antibiotic. This compound is an ester-type prodrug of the active metabolite R-95867. The antibacterial activity of R-95867 was tested against 1,323 clinical isolates of 35 species and was compared with those of oral cephems, i.e., cefteram, cefpodoxime, cefdinir, and cefditoren, and that of a parenteral carbapenem, imipenem. R-95867 exhibited a broad spectrum of activity covering both gram-positive and -negative aerobes and anaerobes. Its activity was superior to those of the other compounds tested against most of the bacterial species tested. R-95867 showed potent antibacterial activity against clinically significant pathogens: methicillin-susceptible Staphylococcus aureus including ofloxacin-resistant strains, Streptococcus pneumoniae including penicillin-resistant strains, Clostridium perfringens, Neisseria spp., Moraxella catarrhalis, most members of the family Enterobacteriaceae, and Haemophilus influenzae (MIC at which 90% of strains are inhibited, < or =0.006 to 0.78 microg/ml). R-95867 was quite stable to hydrolysis by most of the beta-lactamases tested except the metallo-beta-lactamases from Stenotrophomonas maltophilia and Bacteroides fragilis. R-95867 showed potent bactericidal activity against S. aureus and Escherichia coli. Penicillin-binding proteins 1 and 4 of S. aureus and 1Bs, 2, 3, and 4 of E. coli had high affinities for R-95867. The in vivo efficacy of CS-834 was evaluated in murine systemic infections caused by 16 strains of gram-positive and -negative pathogens. The efficacy of CS-834 was in many cases superior to those of cefteram pivoxil, cefpodoxime proxetil, cefdinir, and cefditoren pivoxil, especially against infections caused by S. aureus, penicillin-resistant S. pneumoniae, E. coli, Citrobacter freundii, and Proteus vulgaris. Among the drugs tested, CS-834 showed the highest efficacy against experimental pneumonia in mice caused by penicillin-resistant S. pneumoniae. PMID:9420035

Fukuoka, T; Ohya, S; Utsui, Y; Domon, H; Takenouchi, T; Koga, T; Masuda, N; Kawada, H; Kakuta, M; Kubota, M; Ishii, C; Ishii, C; Sakagawa, E; Harasaki, T; Hirasawa, A; Abe, T; Yasuda, H; Iwata, M; Kuwahara, S

1997-12-01

174

Additional observations and notes on the natural history of the prairie rattlesnake (Crotalus viridis) in Colorado.  

PubMed

On account of their unique anatomy, physiology, natural history, ecology, and behavior, rattlesnakes make ideal subjects for a variety of different scientific disciplines. The prairie rattlesnake (Crotalus viridis) in Colorado was selected for investigation of its relationship to colonies of black-tailed prairie dogs (Cynomys ludovicianus) with regard to spatial ecology. A total of 31 snakes were anesthetized and had radiotransmitters surgically implanted. In addition, at the time of their capture, all snakes underwent the following: (1) they had bacterial culture taken from their mouths for potential isolation of pathogenic bacteria; (2) similarly, they had cloacal bacterial cultures taken to assess potentially harmful bacteria passed in the feces; and (3) they had blood samples drawn to investigate the presence of any zoonotic agents in the serum of the snakes. The results of the study and their implications are discussed here. Traditionally, a low incidence of bacterial wound infection has been reported following snakebite. Nevertheless, the oral cavity of snakes has long been known to house a wide variety of bacterial flora. In our study, 10 different bacterial species were isolated from the mouths of the rattlesnakes, 6 of which are capable of being zoonotic pathogens and inducing human disease. More studies are necessary to see why more rattlesnake bites do not become infected despite the presence of such pathogenic bacteria. The results of fecal bacteria isolated revealed 13 bacterial species, 12 of which can cause disease in humans. Of the snakes whose samples were cultured, 26% were positive for the presence of the pathogen Salmonella arizonae, one of the causative agents of reptile-related salmonellosis in humans. It has long been reported that captive reptiles have a much higher incidence than wild, free-ranging species. This study shows the incidence of Salmonella in a wild, free-ranging population of rattlesnakes. In addition, Stenotrophomonas maltophilia was isolated. This bacterium is associated with wound and soft tissue infections that can lead to sepsis, endocarditis, meningitis, and peritonitis. In addition, this bacterium has been increasingly implicated as an opportunistic pathogen to humans during pregnancies, hospitalizations, malignancies and chemotherapy, chronic respiratory diseases, and presurgical endotracheal intubation. Furthermore, S. maltophilia has an intense resistance to broad-spectrum antibiotics, the results of our study showed the bacterium was resistant to multiple antibiotics. Our results indicate that anyone working with snake feces, dead skin, or their carcasses must follow reasonable hygiene protocols. Rattlesnakes tested for West Nile antibodies had positive results but these were invalidated owing to possible cross-reactivity with other unknown viruses, interference with snake serum proteins, and the fact that the test was not calibrated for rattlesnake serum. Still, the interesting implication remains, should we be regularly testing these animals as sentinels against potentially zoonotic diseases. The results of this study clearly show the value of veterinarians in a multidisciplinary study of this sort and the particular skill set they can offer. Veterinarians must get involved in conservation studies if the biodiversity of the planet is to be preserved. PMID:24331557

Fitzgerald, Kevin T; Shipley, Bryon K; Newquist, Kristin L; Vera, Rebecca; Flood, Aryn A

2013-11-01

175

Characterization of N2O-producing Xanthomonas-like isolates from biofilters as Stenotrophomonas nitritireducens sp. nov., Luteimonas mephitis gen. nov., sp. nov. and Pseudoxanthomonas broegbernensis gen. nov., sp. nov  

Microsoft Academic Search

A group of yellow-pigmented isolates from ammonia-supplied biofilters showed an unusual denitrification reaction. All strains reduced nitrite but not nitrate without production of nitrogen (N2). The only product found was nitrous oxide (N2O). The strains were divided into two clusters and one separate strain by their fatty acid profiles, which were similar to the fatty acid profiles of the genera

Wolfgang Finkmann; Karlheinz Altendorf; Erko Stackebrandt

176

Microbial profile and antibiotic sensitivity pattern in bile cultures from endoscopic retrograde cholangiography patients  

PubMed Central

AIM: To identify the frequency of bacterial growth, the most commonly grown bacteria and their antibiotic susceptibility, and risk factors for bacterial colonization in bile collected from patients with different biliary diseases. METHODS: This prospective study was conducted between April 2010 and August 2011. Patients with various biliary disorders were included. Bile was aspirated by placing a single-use, 5F, standard sphincterotome catheter into the bile duct before the injection of contrast agent during endoscopic retrograde cholangiopancreaticography (ERCP). Bile specimens were transported to the microbiology laboratory in blood culture bottles within an anaerobic transport system. Bacteria were cultured and identified according to the standard protocol used in our clinical microbiology laboratory. The susceptibilities of the organisms recovered were identified using antimicrobial disks, chosen according to the initial gram stain of the positive cultures. RESULTS: Ninety-one patients (27% male, mean age 53.7 ± 17.5 years, range: 17-86 years) were included in the study. The main indication for ERCP was benign biliary disease in 79 patients and malignant disease in 12 patients. The bile culture was positive for bacterial growth in 46 out of 91 (50.5%) patients. The most frequently encountered organisms were Gram-negative bacteria including Escherichia coli (28.2%), Pseudomonas (17.3%) and Stenotrophomonas maltophilia (15.2%). There were no significant differences between patients with malignant and benign disease (58% vs 49%, P = 0.474), patients with acute cholangitis and without acute cholangitis (52.9% vs 50%, P = 0.827), patients who were empirically administered antibiotics before intervention and not administered (51.4% vs 60.7%, P = 0.384), with regard to the bacteriobilia. We observed a large covering spectrum or low resistance to meropenem, amikacin and imipenem. CONCLUSION: We did not find a significant risk factor for bacteriobilia in patients with biliary obstruction. A bile sample for microbiological analysis may become a valuable diagnostic tool as it leads to more accurate selection of antibiotics for the treatment of cholangitis. PMID:22826624

Kaya, Muhsin; Bestas, Remzi; Bacalan, Fatma; Bacaks?z, Ferhat; Arslan, Esma Gulsun; Kaplan, Mehmet Ali

2012-01-01

177

In vitro activity of BAY 12-8039, a new fluoroquinolone.  

PubMed Central

The in vitro activity of BAY 12-8039, a new fluoroquinolone, was studied in comparison with those of ciprofloxacin, trovafloxacin (CP 99,219), cefpodoxime, and amoxicillin-clavulanate against gram-negative, gram-positive, and anaerobic bacteria. Its activity against mycobacteria and chlamydia was also investigated. BAY 12-8039 was active against members of the family Enterobacteriaceae (MIC at which 90% of strains tested were inhibited [MIC90S] < or = 1 microgram/ml, except for Serratia spp. MIC90 2 microgram/ml), Neisseria spp. (MIC90S, 0.015 microgram/ml), Haemophilus influenzae (MIC90, 0.03 microgram/ml), and Moraxella catarrhalis (MIC90, 0.12 micrgram/ml), and these results were comparable to those obtained for ciprofloxacin and trovafloxacin. Against Pseudomonas aeruginosa, the quinolones were more active than the beta-lactam agents but BAY 12-8039 was less active than ciprofloxacin. Strains of Stenotrophomonas maltophilia were fourfold more susceptible to BAY 12-8039 and trovafloxacin (MIC90S, 2 micrograms/ml) than to ciprofloxacin. BAY 12-8039 was as active as trovafloxacin but more active than ciprofloxacin against Streptococcus pneumoniae (MIC90, 0.25 microgram/ml) and methicillin-susceptible Staphylococcus auerus (MIC90S, 0.12 micrograms/ml). The activity of BAY 12-8039 against methicillin-resistant S. aureus (MIC90, 2 micrograms/ml) was lower than that against methicillin-susceptible strains. BAY 12-8039 was active against anaerobes (MIC90S < or = 2 micrograms/ml), being three- to fourfold more active against Bacteroides fragilis, Prevotella spp., and Clostridium difficile than was ciprofloxacin. Against Mycobacterium tuberculosis, BAY 12-8039 exhibited activity comparable to that of rifampin (MICs < or = 0.5 micrograms/ml). Against Chlamydia trachomatis and Chlamydia pneumoniae BAY 12-8039 was more active (MICs < or = 0.12 microgram/ml) than either ciprofloxacin or erythromycin and exhibited a greater lethal effect than either to these two agents. The protein binding of BAY 12-8039 was determined at 1 and 5 micrograms/ml as 30 and 26.4%, respectively. The presence of human serum (at 20 or 70%) had no marked effect on the in vitro activity of BAY 12-8039. PMID:8980763

Woodcock, J M; Andrews, J M; Boswell, F J; Brenwald, N P; Wise, R

1997-01-01

178

Application of a constructed wetland system for polluted stream remediation  

NASA Astrophysics Data System (ADS)

In 2010, the multi-function Kaoping River Rail Bridge Constructed Wetland (KRRBW) was constructed to improve the stream water quality and rehabilitate the ecosystem of the surrounding environment of Dashu Region, Kaohsiung, Taiwan. The KRRBW consists of five wetland basins with a total water surface area of 15 ha, a total hydraulic retention time (HRT) of 10.1 days at a averaged flow rate of 14 740 m3/day, and an averaged water depth of 1.1 m. The influent of KRRBW coming from the local drainage systems containing untreated domestic, agricultural, and industrial wastewaters. Based on the quarterly investigation results of water samples taken in 2011-2012, the overall removal efficiencies were 91% for biochemical oxygen demand (BOD), 75% for total nitrogen (TN), 96% for total phosphorus (TP), and 99% for total coliforms (TC). The calculated first-order decay rates for BOD, TN, TP, NH3-N, and TC ranged from 0.14 (TN) to 0.42 (TC) 1/day. This indicates that the KRRBW was able to remove organics, TC, and nutrients effectively. The high ammonia/nitrate removal efficiency indicates that nitrification and denitrification processes occurred simultaneously in the wetland system, and the detected nitrite concentration confirmed the occurrence of denitrification/nitrification. Results from sediment analyses reveal that the sediment contained high concentrations of organics (sediment oxygen demand = 1.9-5.2 g O2/m2 day), nutrients (up to 15.8 g total nitrogen/kg of sediment and 1.48 g total phosphorus/kg of sediment), and metals (up to 547 mg/kg of Zn and 97 mg/kg of Cu). Appropriate wetland management strategies need to be developed to prevent the release of contaminants into the wetland system. The wetland system caused the variations in the microbial diversities and dominant microbial bacteria. Results show the dominant nitrogen utilization bacteria including Denitratisoma oestradiolicum, Nitrosospira sp., Nitrosovibrio sp., D. oestradiolicum, Alcaligenes sp., Steroidobacter denitrificans, Hydrocarboniphaga effuse were responsible for nitrogen removal, and the dominant carbon degrading bacteria (Stenotrophomonas maltophilia, H. effuse, Alcaligenes sp., Pseudomonas sp., Fusibacter sp., Chlofoflexi, Guggenheimella bovis, Bacillus pumilus) were responsible for carbon reduction. The denaturing gradient gel electrophoresis (DGGE) and nucleotide sequence techniques provide a guide for microbial ecology evaluation, which can be used as an indication of contaminants removal. Results from this study show that constructed wetlands have the potential to be developed into an environmentally acceptable river water quality improvement and wastewater polishment alternative for practical application.

Tu, Y. T.; Chiang, P. C.; Yang, J.; Chen, S. H.; Kao, C. M.

2014-03-01

179

Multidrug-resistant Gram-negative infections: what are the treatment options?  

PubMed

The emergence of multidrug-resistant (MDR) Gram-negative bacilli creates a challenge in the treatment of nosocomial infections. While the pharmaceutical pipeline is waning, two revived old antibacterials (colistin and fosfomycin), a newer one (tigecycline) and an 'improved' member of an existing class (doripenem) are the only therapeutic options left. The class of polymyxins, known since 1947 and represented mostly by polymyxin B and polymyxin E (colistin), has recently gained a principal role in the treatment of the most problematic MDR Gram-negative pathogens (such as Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae and Stenotrophomonas maltophilia). Future prospective studies are needed to answer important clinical questions, such as the possible benefit of combination with other antimicrobials versus monotherapy, the efficacy of colistin in neutropenic hosts and the role of inhaled colistin. As new pharmacokinetic data emerge, clarification of the pharmacokinetic/pharmacodynamic (PK/PD) profile of colistin as well as appropriate dosing seems urgent, while development of resistance must be carefully monitored. Fosfomycin tromethamine, a synthetic salt of fosfomycin discovered in 1969, has regained attention because of its in vitro activity against extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae and MDR P. aeruginosa. Although in use for decades in oral and parenteral formulations for a variety of infections without significant toxicity, its clinical utility in MDR infections remains to be explored in future studies. Tigecycline, the first representative of the new class of glycylcyclines, holds promise in infections from MDR K. pneumoniae (K. pneumoniae carbapenemase [KPC]- and ESBL-producing strains) and Enterobacteriaceae with various mechanisms of resistance. The in vitro activity of tigecycline against A. baumannii makes it a tempting option, as it is currently the most active compound against MDR strains along with colistin. However, the usual minimum inhibitory concentration values of this pathogen are approximately 2 mg/L and compromise clinical outcomes based on PK/PD issues. Its advantageous penetration into various tissues is useful in infections of the skin and soft tissues as well as intra-abdominal infections (official indications), whereas low serum concentrations compromise its use in bloodstream infections. Therefore, prospective studies with dose escalation are urgently needed, as well as clarification of its role in nosocomial pneumonia, after poor results in the study of ventilator-associated pneumonia. Finally, doripenem, the recently licensed member of the carbapenems (without significant spectrum alterations from the ascendant members) seems to possess a lower potential for resistance selection and a more favourable pharmacokinetic profile when given as an extended infusion. The latter strategy could prove helpful in overcoming low level resistance of A. baumannii and P. aeruginosa strains. PMID:19747006

Giamarellou, Helen; Poulakou, Garyphallia

2009-10-01

180

Stability of a promiscuous plasmid in different hosts: no guarantee for a long-term relationship.  

PubMed

Broad-host-range (BHR) IncP-1 plasmids have the ability to transfer between and replicate in nearly all species of the Alpha-, Beta- and Gammaproteobacteria, but surprisingly few data are available on the stability of these plasmids in strains within their host range. Moreover, even though molecular interactions between the bacterial host and its plasmid(s) exist, no systematic study to date has compared the stability of the same plasmid among different hosts. The goal of this study was to examine whether the stability characteristics of an IncP-1 plasmid can be variable between strains within the host range of the plasmid. Therefore, 19 strains within the Alpha-, Beta- or Gammaproteobacteria carrying the IncP-1beta plasmid pB10 were serially propagated in non-selective medium and the fraction of segregants was monitored through replica-picking. Remarkably, a large variation in the stability of pB10 in different strains was found, even between strains within the same genus or species. Ten strains showed no detectable plasmid loss over about 200 generations, and in two strains plasmid-free clones were only sporadically observed. In contrast, three strains, Pseudomonas koreensis R28, Pseudomonas putida H2 and Stenotrophomonas maltophilia P21, exhibited rapid plasmid loss within 80 generations. Parameter estimation after mathematical modelling of these stability data suggested high frequencies of segregation (about 0.04 per generation) or high plasmid cost (i.e. a relative fitness decrease in plasmid-bearing cells of about 15 and 40 %), which was confirmed experimentally. The models also suggested that plasmid reuptake by conjugation only played a significant role in plasmid stability in one of the three strains. Four of the 19 strains lost the plasmid very slowly over about 600 generations. The erratic decrease of the plasmid-containing fraction and simulation of the data with a new mathematical model suggested that plasmid cost was variable over time due to compensatory mutations. The findings of this study demonstrate that the ability of a so-called 'BHR' plasmid to persist in a bacterial population is influenced by strain-specific traits, and therefore observations made for one strain should not be generalized for the entire species or genus. PMID:17259616

De Gelder, Leen; Ponciano, José M; Joyce, Paul; Top, Eva M

2007-02-01

181

Broad-range PCR, cloning and sequencing of the full 16S rRNA gene for detection of bacterial DNA in synovial fluid samples of Tunisian patients with reactive and undifferentiated arthritis  

PubMed Central

Introduction Broad-range rDNA PCR provides an alternative, cultivation-independent approach for identifying bacterial DNA in reactive and other form of arthritis. The aim of this study was to use broad-range rDNA PCR targeting the 16S rRNA gene in patients with reactive and other forms of arthritis and to screen for the presence of DNA from any given bacterial species in synovial fluid (SF) samples. Methods We examined the SF samples from a total of 27 patients consisting of patients with reactive arthritis (ReA) (n = 5), undifferentiated arthritis (UA) (n = 9), rheumatoid arthritis (n = 7), and osteoarthritis (n = 6) of which the latter two were used as controls. Using broad-range bacterial PCR amplifying a 1400 bp fragment from the 16S rRNA gene, we identified and sequenced at least 24 clones from each SF sample. To identify the corresponding bacteria, DNA sequences were compared to the EMBL (European Molecular Biology Laboratory) database. Results Bacterial DNA was identified in 20 of the 27 SF samples (74, 10%). Analysis of a large number of sequences revealed the presence of DNA from more than one single bacterial species in the SF of all patients studied. The nearly complete sequences of the 1400 bp were obtained for most of the detected species. DNA of bacterial species including Shigella species, Escherichia species, and other coli-form bacteria as well as opportunistic pathogens such as Stenotrophomonas maltophilia and Achromobacter xylosoxidans were shared in all arthritis patients. Among pathogens described to trigger ReA, DNA from Shigella sonnei was found in ReA and UA patients. We also detected DNA from rarely occurring human pathogens such as Aranicola species and Pantoea ananatis. We also found DNA from bacteria so far not described in human infections such as Bacillus niacini, Paenibacillus humicus, Diaphorobacter species and uncultured bacterium genera incertae sedis OP10. Conclusions Broad-range PCR followed by cloning and sequencing the entire 16S rDNA, allowed the identification of the bacterial DNA environment in the SF samples of arthritic patients. We found a wide spectrum of bacteria including those known to be involved in ReA and others not previously associated with arthritis. PMID:19570210

Siala, Mariam; Gdoura, Radhouane; Fourati, Hela; Rihl, Markus; Jaulhac, Benoit; Younes, Mohamed; Sibilia, Jean; Baklouti, Sofien; Bargaoui, Naceur; Sellami, Slaheddine; Sghir, Abdelghani; Hammami, Adnane

2009-01-01

182

Studies on the occurrence of Gram-negative bacteria in ticks: Ixodes ricinus as a potential vector of Pasteurella.  

PubMed

A total of 372 Ixodes ricinus ticks (101 females, 122 males, and 149 nymphs) collected by flagging in 6 mixed woodlands of eastern Poland were examined by culture for the presence of internal Gram-negative bacteria other than Borrelia burgdorferi. Adult ticks were examined in pools of 2 specimens each and nymphs were examined in pools of 3-5 specimens each. Ticks were disinfected in 70 % ethanol and homogenized in 0.85% NaCl. The diluted homogenate was inoculated onto 3 kinds of agar media: buffered charcoal yeast extract (BCYE-alpha) for isolation of fastidious Gram-negative bacteria, eosin methylene blue agar (EMB) for isolation of enterobacteria, and tryptic soya agar for isolation of all other non-fastidious Gram-negative bacteria. The Gram-negative isolates were identified with the API Systems 20E and NE microtests. A total of 9 species of Gram-negative bacteria were identified, of which the commonest were strains determined as Pasteurella pneumotropica/haemolytica, which were isolated on BCYE-alpha agar from ticks collected in all 6 examined woodlands. The total number of these strains (49) exceeded the total number of all other strains of Gram-negative bacteria recovered from ticks (30). Of the total number of examined ticks, the minimum infection rate with Pasteurella pneumotropica/haemolytica was highest in females (18.8%), and slightly lower in males (12.3%) and nymphs (10%). Besides Pasteurella pneumotropica/haemolytica, the following species of Gram-negative bacteria were isolated from examined ticks: Pantoea agglomerans, Serratia marcescens, Serratia plymuthica on EMB agar and Aeromonas hydrophila, Burkholderia cepacia, Chromobacterium violaceum, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia on tryptic soya agar. Minimal infection rates with these bacteria were low, ranging from 0.7-5.9%. Of the isolated bacteria, Chromobacterium violaceum, Pasteurella pneumotropica/haemolytica, Pseudomonas aeruginosa, and Serratia marcescens are potentially pathogenic for man and/or animals. In particular, the common occurrence of Pasteurella pneumotropica/haemolytica in Ixodes ricinus ticks poses a potential risk of pasteurellosis for humans and animals exposed to tick bites. PMID:15627343

Stojek, Nimfa Maria; Dutkiewicz, Jacek

2004-01-01

183

Antibiotic resistance from wastewater oxidation ponds.  

PubMed

In an extensive, multiyear study of antibiotic resistance from wastewater oxidation ponds, five mobile home park wastewater oxidation ponds in Clarke and Oconee counties were shown to be discharging high numbers of antibiotic-resistant bacteria into the waterways of North Georgia. This effluent contributed to higher nitrogen, phosphorus, and fecal coliform levels in creeks downstream from the ponds. A survey of residents revealed that many people did not complete their antibiotic prescriptions, and the majority flushed leftover antibiotic medications down the toilet. In the pond discharges, resistance was found to eighteen antibiotics: amikacin, amoxicillin/clavulanic acid, ampicillin, apramycin, cefoxitin, ceftiofur, ceftriaxone, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, imipenem, kanamycin, naladixic acid, streptomycin, sulphamethoxazole, trimethoprim/sulphamethoxazole, and tetracycline. The discharged bacteria contained both integrons and plasmids, the latter being transferable to a laboratory strain of Escherichia coil (E. coli). A turtle was found living at a pond discharge site with multiply-antibiotic-resistant bacteria in its feces. Last year, RNA fingerprinting conclusively documented the survival of three multiply-resistant important pathogenic bacteria. Ceftriaxone-resistant Stenotrophomonas maltophilia and Pseudomonas aerogenosa and a ciprofloxacin-resistant E. coli were traced through oxidation pond stages and into the discharge, thus documenting that the pathogens survived the treatment process. In addition, a potential pathogen, a serotype group D Salmonella spp., was found in the discharge. In this study, tetracycline-resistance genes C and G were detected in the first and second stages of the oxidation pond and the discharge went directly into the environment. These genes are generally found in intestinal bacteria, so it can be inferred that they are from a human source. Antimicrobial residue from the beta-lactam family of antibiotics was found in all oxidation pond stages and in the creek above the pond. Tetracycline residue was found in the first and second stages of the pond. In addition to the antibiotics, genes coding for antibiotic resistance and the antibiotics themselves were documented to survive oxidation pond treatment. Tetracycline-resistant genes were identified in the oxidation pond stages and in the discharge going into the environment. A model was also developed to study oxidation pond function in the laboratory. A biofilm was created using a highly antibiotic-resistant Salmonella typhimurium 3/97, and pond water was added. The biofilm was processed via a rotating disk bioreactor specifically designed to study biofilms in nature, but with conditions that were more favorable to bacterial inhibition than those in nature. Cultures revealed that, under these optimal conditions, S. typhimurium 3/97 was still present in this in vitro system. Thus, the competitive inhibition process that helps to remove bacteria in oxidation ponds did not effectively remove an important bacterium, S. typhimurium 3/97, in this mock oxidation pond. The bioreactor model developed in this study can be used to further investigate discharges from oxidation ponds. From this data, it is apparent that the problem is two-fold. A cost-effective technique must be developed that inactivates antibiotic-resistant bacteria in oxidation pond discharges and also removes the antibiotics. A public awareness campaign was initiated by the author to encourage proper use and disposal of antibiotics, as flushing them is a common practice in the United States. PMID:16381146

Mispagel, Heather; Gray, Jeffrey T

2005-01-01

184

An overview of the kinetic parameters of class B beta-lactamases.  

PubMed Central

The catalytic properties of three class B beta-lactamases (from Pseudomonas maltophilia, Aeromonas hydrophila and Bacillus cereus) were studied and compared with those of the Bacteroides fragilis enzyme. The A. hydrophila beta-lactamase exhibited a unique specificity profile and could be considered as a rather specific 'carbapenemase'. No relationships were found between sequence similarities and catalytic properties. The problem of the repartition of class B beta-lactamases into sub-classes is discussed. Improved purification methods were devised for the P. maltophilia and A. hydrophila beta-lactamases including, for the latter enzyme, a very efficient affinity chromatography step on a Zn(2+)-chelate column. Images Figure 1 PMID:8471035

Felici, A; Amicosante, G; Oratore, A; Strom, R; Ledent, P; Joris, B; Fanuel, L; Frere, J M

1993-01-01

185

INFLUENCE OF SOLID SURFACE, ADHESIVE ABILITY, AND INOCULUM SIZE ON BACTERIAL COLONIZATION IN MICROCOSM STUDIES  

EPA Science Inventory

Microcosm studies were performed to evaluate the effect of solid surfaces, bacterial adhesive ability, and inoculum size on colonization success and persistence of P. fluorescens or X maltophilia, each with a Tn5 insertion that conferred resistance to kanamycin and streptomycin. ...

186

In vitro Activity of Cefdinir (FK 482, PD 134393, CI983): A New Orally Active Cephalosporin  

Microsoft Academic Search

Cefdinir is a new orally active cephalosporin which is undergoing in vitro and in vivo evaluations. Using the standard agar dilution method we compared the in vitro activity of this drug with other (3-lactam antibiotics against clinical isolates or Ente-robacteriaceae (625 strains), Pseudomonas aeruginosa (68 strains), Xanthomonas maltophilia (36 strains), Acinetobacter (52 strains), Aeromonas hydrophilia (47 strains), staphylococci (364 strains)

Hussain Qadri; Yoshio Ueno; Hishama Saldin; Burke A. Cunha

1993-01-01

187

Microbial transformation of the anti-diabetic agent corosolic acid.  

PubMed

Biotransformation of corosolic acid (1) by Cochliobolus lunatus and Streptomyces asparaginoviolaceus afforded four metabolites, which were identified by using (1)H NMR, (13)C NMR, DEPT, HSQC, HMBC and NOESY spectral data. Biotransformation of corosolic acid by C. lunatus R.R. Nelson & Haasis CGMCC 3.4381 produced three metabolites: 2?,3?,21?-trihydroxyurs-12-en-28-oic acid (2), 2?,3?,7?,21?-tetrahydroxy-urs-12-en-28-oic acid (3) and 2?,3?-dihydroxy-21-oxours-12-en-28-oic acid (4). Incubation of corosolic acid with growing cultures of S. asparaginoviolaceus CGMCC 4.0175 afforded metabolite 2?,3?,30-trihydroxyurs-12-en-28-oic acid (5). All the metabolites were reported for the first time. The substrate and four metabolites, along with four products obtained previously, were evaluated for their inhibitory effects on ?-glucosidase; all the triterpenes tested showed potent inhibitory effects. PMID:25190540

Feng, Xu; Li, Dai-Ping; Zhang, Ze-Sheng; Chu, Zhi-Yong; Luan, Jie

2014-11-01

188

Draft Genome Sequence of the Bioelectricity-Generating and Dye-Decolorizing Bacterium Proteus hauseri Strain ZMd44.  

PubMed

Proteus hauseri ZMd44 (CGMCC 6746), as a crucial biodecolorizing, bioelectricity-generating, and copper-resistant bacterium, is distinguished from the urinary pathogens Proteus penneri and Proteus mirabilis. To further investigate the genetic functions of this strain, the genome sequence and annotation of its open reading frames, which consist of 3,875,927 bp (G+C content, 38.12%), are presented here. PMID:24435854

Wang, Nan; Ng, I-Son; Chen, Po Ting; Li, Yuzhe; Chen, Yi-Chung; Chen, Bor-Yann; Lu, Yinghua

2014-01-01

189

Draft Genome Sequence of the Bioelectricity-Generating and Dye-Decolorizing Bacterium Proteus hauseri Strain ZMd44  

PubMed Central

Proteus hauseri ZMd44 (CGMCC 6746), as a crucial biodecolorizing, bioelectricity-generating, and copper-resistant bacterium, is distinguished from the urinary pathogens Proteus penneri and Proteus mirabilis. To further investigate the genetic functions of this strain, the genome sequence and annotation of its open reading frames, which consist of 3,875,927 bp (G+C content, 38.12%), are presented here. PMID:24435854

Wang, Nan; Li, Yuzhe; Chen, Yi-Chung; Chen, Bor-Yann; Lu, Yinghua

2014-01-01

190

Metabolic flux analysis of Gluconacetobacter xylinus for bacterial cellulose production.  

PubMed

Metabolic flux analysis was used to reveal the metabolic distributions in Gluconacetobacter xylinus (CGMCC no. 2955) cultured on different carbon sources. Compared with other sources, glucose, fructose, and glycerol could achieve much higher bacterial cellulose (BC) yields from G. xylinus (CGMCC no. 2955). The glycerol led to the highest BC production with a metabolic yield of 14.7 g/mol C, which was approximately 1.69-fold and 2.38-fold greater than that produced using fructose and glucose medium, respectively. The highest BC productivity from G. xylinus CGMCC 2955 was 5.97 g BC/L (dry weight) when using glycerol as the sole carbon source. Metabolic flux analysis for the central carbon metabolism revealed that about 47.96 % of glycerol was transformed into BC, while only 19.05 % of glucose and 24.78 % of fructose were transformed into BC. Instead, when glucose was used as the sole carbon source, 40.03 % of glucose was turned into the by-product gluconic acid. Compared with BC from glucose and fructose, BC from the glycerol medium showed the highest tensile strength at 83.5 MPa, with thinner fibers and lower porosity. As a main byproduct of biodiesel production, glycerol holds great potential to produce BC with superior mechanical and microstructural characteristics. PMID:23640364

Zhong, Cheng; Zhang, Gui-Cai; Liu, Miao; Zheng, Xin-Tong; Han, Pei-Pei; Jia, Shi-Ru

2013-07-01

191

Halobacterium rubrum sp. nov., isolated from a marine solar saltern.  

PubMed

Halophilic archaeal strain TGN-42-S1(T) was isolated from the Tanggu marine solar saltern, China. Cells from strain TGN-42-S1(T) were observed to be pleomorphic rods, stained Gram-negative, and formed red-pigmented colonies on solid media. Strain TGN-42-S1(T) was found to be able to grow at 20-50 °C (optimum 35-37 °C), at 1.7-4.8 M NaCl (optimum 3.1 M), at 0-1.0 M MgCl2 (optimum 0.1 M), and at pH 5.0-9.0 (optimum pH 7.0-7.5). The cells lysed in distilled water, and the minimal NaCl concentration to prevent cell-lysis was found to be 10 % (w/v). The major polar lipids of the strain were phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, galactosyl mannosyl glucosyl diether (TGD-1), sulfated galactosyl mannosyl glucosyl diether (S-TGD-1), sulfated galactosyl mannosyl galactofuranosyl glucosyl diether (S-TeGD), and three unidentified glycolipids which were chromatographically identical to those of the Halobacterium species. The 16S rRNA gene and rpoB' gene of strain TGN-42-S1(T) were phylogenetically related to the corresponding genes of Halobacterium jilantaiense CGMCC 1.5337(T) (98.8 and 93.5 % nucleotide identity, respectively), Halobacterium salinarum CGMCC 1.1958(T) (98.4 and 91.9 %), and Halobacterium noricense JCM 15102(T) (96.9 and 91.1 %). The DNA G + C content of strain TGN-42-S1(T) was determined to be 69.2 mol %. Strain TGN-42-S1(T) showed low DNA-DNA relatedness with Hbt. jilantaiense CGMCC 1.5337(T) and Hbt. salinarum CGMCC 1.1958(T), the most closely related members of the genus Halobacterium. The phenotypic, chemotaxonomic, and phylogenetic properties suggested that strain TGN-42-S1(T) (=CGMCC 1.12575(T) =JCM 19908(T)) represents a new species of Halobacterium, for which the name Halobacterium rubrum sp. nov. is proposed. PMID:25112838

Han, Dong; Cui, Heng-Lin

2014-12-01

192

Effects of different osmolarities on bacterial biofilm formation  

PubMed Central

Biofilm formation depends on several factors. The influence of different osmolarities on bacterial biofilm formation was studied. Two strains (Enterobacter sp. and Stenotrophomonas sp.) exhibited the most remarkable alterations. Biofilm formation is an important trait and its use has been associated to the protection of organisms against environmental stresses. PMID:25242950

Kavamura, Vanessa Nessner; de Melo, Itamar Soares

2014-01-01

193

Production of biosurfactant “Biosur-Pm” by Pseudomonas maltophila CSV89: characterization and role in hydrocarbon uptake  

Microsoft Academic Search

Pseudomonas maltophilia CSV89, a soil bacterium, produces an extracellular biosurfactant, “Biosur-Pm”. The partially purified product is nondialyzable and chemically composed of 50% protein and 12–15% sugar, which indicates the complex nature of Biosur-Pm. It reduces the surface tension of water from 73 to 53×10-3 N m-1 and has a critical micellar concentration of 80 mg\\/l. Compared to aliphatic hydrocarbons, Biosur-Pm

Prashant S. Phale; Handanahal S. Savithri; N. Appaji Rao; Chelakara S. Vaidyanathan

1995-01-01

194

60Co-irradiation as an alternate method for sterilization of penicillin G, neomycin, novobiocin, and dihydrostreptomycin  

Microsoft Academic Search

The effects of the use of 60Co-irradiation to sterilize antibiotics were evaluated. The antibiotic powders were only occasionally contaminated with microorganisms. The D-values of the products and environmental isolates were 0.028, 0.027, 0.015, 0.046, 0.15, 0.018, and 0.19 Mrads for Aspergillus species (UC 7297, 7298), A. fumigatus (UC 7299), Rhodotorula species (UC 7300), Penicillium oxalicum (UC 7269), Pseudomonas maltophilia (UC

Kiyoshi Tsuji; Paul D. Rahn; Kathy A. Steindler

1983-01-01

195

In vitro activity of A-86719.1, a novel 2-pyridone antimicrobial agent.  

PubMed Central

This study evaluated the in vitro activity of A-86719.1, a novel 2-pyridone antimicrobial agent. The drug inhibited all tested members of the family Enterobacteriaceae at < or = 0.5 microgram/ml and all tested Pseudomonas aeruginosa, Burkholderia (Pseudomonas) cepacia, and Xanthomonas maltophilia strains at < or = 2 micrograms/ml. All but two strains of gram-positive bacteria were inhibited by < or = 1 microgram of the new drug per ml, including isolates highly resistant to ciprofloxacin. PMID:7785983

Eliopoulos, G M; Wennersten, C B; Cole, G; Chu, D; Pizzuti, D; Moellering, R C

1995-01-01

196

Permeabilization of Microbacterium oxylans shifts the conversion of puerarin from puerarin-7-O-glucoside to puerarin-7-O-fructoside.  

PubMed

The main product of the conversion of puerarin by unpermeabilized cells of bacterium Microbacterium oxydans CGMCC 1788 was puerarin-7-O-glucoside (241 +/- 31.9 microM). Permeabilization with 40% ethanol could not increase conversion yield, whereas it resulted in change of main product; a previous trace product became a main product (213 +/- 48.0 microM) which was identified as a novel puerarin-7-O-fructoside by electrospray ionization time-of-flight MS, (13)C NMR, (1)H NMR, and GC-MS analysis of sugar composition, and puerarin-7-O-glucoside became a trace product (14.8 +/- 5.4 microM). However, the extract from cells of M. oxydans CGMCC 1788 permeabilized with ethanol converted puerarin to form 113.9 +/- 27.7 microM puerarin-7-O-glucoside and 187.8 +/- 29.5 microM puerarin-7-O-fructoside under the same conditions. When unpermeabilized intact cells were recovered and used repeatedly for the conversion of puerarin, with increase of reuse times, the yield of puerarin-7-O-glucoside gradually decreased, whereas the yield of puerarin-7-O-fructoside increased gradually in the conversion mixture. The main product of the conversion of puerarin by the tenth recycled unpremerbilized cells was puerarin-7-O-fructoside (288.4 +/- 24.0 microM). Therefore, the change of permeability of cell membrane of bacterium M. oxydans CGMCC 1788 contributed to the change of conversion of the product's composition. PMID:19943046

Yu, Cigang; Xu, Haidong; Huang, Guodong; Chen, Ting; Liu, Guiyou; Chai, Nan; Ji, Yin; Wang, Siyuan; Dai, Yijun; Yuan, Sheng

2010-04-01

197

Candida mengyuniae sp. nov., a metsulfuron-methyl-resistant yeast.  

PubMed

A metsulfuron-methyl-resistant yeast strain, JHL(T), was isolated from metsulfuron-methyl-contaminated soil collected in Jiangsu Province, China. Through morphological and physiological analysis as well as a molecular phylogenetic analysis based on the 26S rRNA gene D1/D2 region and internal transcribed spacer (ITS), this strain, which forms a clade with Candida vartiovaarae and a teleomorphic species, Williopsis saturnus, was revealed to represent a novel species in the genus Candida. The name Candida mengyuniae sp. nov. (type strain JHL(T)=CGMCC 2.3681(T)=CBS 10845(T)) is proposed for this novel species. PMID:19406825

Chen, Bo; Huang, Xing; Zheng, Jin-Wei; Li, Shun-Peng; He, Jian

2009-05-01

198

Study on the bacterial midgut microbiota associated to different Brazilian populations of Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae).  

PubMed

The bacterial community associated with the midgut of three Brazilian Lutzomyia longipalpis (Lutz & Neiva) populations, two from endemic areas for visceral leishmaniasis (Jacobina, Bahia State and São Luís, Maranhão State) and one from a non-endemic area (Lapinha Cave, Minas Gerais State), was identified. Five groups, 35 females each, from each population were separated; a total of 175 females per collecting area were analyzed. The species identification was based on molecular and traditional bacteriological methods. All bacteria were either affiliated to non-Enterobacteriaceae, such as Acinetobacter, Burkholderia, Flavimonas, Pseudomonas and Stenotrophomonas, or and to Enterobacteriaceae, such as Citrobacter, Enterobacter, Escherichia, Klebsiella, Serratia, Pantoea, Morganella and Weeksella. Stenotrophomonas was found to be associated with all three populations studied. In addition, Serratia spp., which are well documented as laboratory contaminant of insects, were detected only in the Jacobina population. We also discuss the impact of the colonization of insect gut by bacteria on the development and transmission of pathogens. PMID:19061048

Gouveia, Cheryl; Asensi, Marise D; Zahner, Viviane; Rangel, Elizabeth F; Oliveira, Sandra M P de

2008-01-01

199

Home-Use Nebulizers: a Potential Primary Source ofBurkholderia cepaciaand Other Colistin-Resistant, Gram-Negative Bacteria in Patients with Cystic Fibrosis  

Microsoft Academic Search

Inhalation of aerosols contaminated with gram-negative bacteria generated from home-use nebulizers used by cystic fibrosis (CF) patients may be a primary route for bacterial colonization of the lung. Burkholderia cepaciawas isolated from 3 to 35 home-use nebulizers, andStenotrophomonas maltophiliawas isolated from 4 of 35 home-use nebulizers. Sputum cultures for two patients whose nebulizers were contaminated with B. cepaciadid not yield

GRAHAM R. HUTCHINSON; SALLY PARKER; JENNIFER A. PRYOR; FRAN DUNCAN-SKINGLE; PETER N. HOFFMAN; MARGARET E. HODSON; MARY E. KAUFMANN; ANDTYRONE L. PITT

200

Cloning of mpd gene from a chlorpyrifos-degrading bacterium and use of this strain in bioremediation of contaminated soil  

Microsoft Academic Search

An effective chlorpyrifos-degrading bacterium (named strain YC-1) was isolated from the sludge of the wastewater treating system of an organophosphorus pesticides manufacturer. Based on the results of phenotypic features, phylogenetic similarity of 16S rRNA gene sequences and BIOLOG test, strain YC-1 was identified as the genus Stenotrophomonas. The isolate utilized chlorpyrifos as the sole source of carbon and phosphorus for

Chao Yang; Na Liu; Xinmin Guo; Chuanling Qiao

201

Atrazine biodegradation by a bacterial community immobilized in two types of packed-bed biofilm reactors  

Microsoft Academic Search

Through selective enrichment of atrazine-metabolizing microorganisms, a microbial community was selected from agricultural\\u000a soil. Bacterial isolates, identified by their closest similarity with 16S rDNA sequences stored in NCBI GeneBank, belonged\\u000a to the genera: Massilia, Stenotrophomonas, Klebsiella, Sphingomonas, Ochrobactrum, Arthrobacter, Microbacterium, Xanthomonas and Ornithinimicrobium. From these strains, only the first six used atrazine as nitrogen and carbon source. The microbial community

Alberto Macías-Flores; Angélica Tafoya-Garnica; Nora Ruiz-Ordaz; Angélica Salmerón-Alcocer; Cleotilde Juárez-Ramírez; Deifilia Ahuatzi-Chacón; María Elena Mondragón-Parada; Juvencio Galíndez-Mayer

2009-01-01

202

Mutation-Screening of Pleurotus Ferulae with High Temperature Tolerance by Nitrogen Ion Implantation  

NASA Astrophysics Data System (ADS)

In order to obtain Pleurotus ferulae with high temperature tolerance, conidiophores of wild type strain ACK were implanted with nitrogen ions in energy of 5 ~15 keV and dose of 1.5 × 1015 ~ 1.5 × 1016 cm-2, and a mutant CGMCC1763 was isolated subsequently through thermotolerant screening method. It was found that during riper period the surface layer mycelium of the mutant in mushroom bag wasn't aging neither grew tegument even above 30° C. The mycelium endurable temperature of the mutant was increased by 5°C compared to that of the wild type strain. The fruiting bodies growth temperature of the mutant was 18 ~22°C in daytime and 8~14°C at night. The highest growth temperature of fruiting bodies of the mutant was increased about 7°C w.r.t. that of original strain. Through three generations investigations, it was found that the mutant CGMCC1763 was stable with high temperature tolerance.

Chen, Henglei; Wan, Honggui; Zhang, Jun; Zeng, Xianxian

2008-08-01

203

Ethanol Production from Nondetoxified Dilute-Acid Lignocellulosic Hydrolysate by Cocultures of Saccharomyces cerevisiae Y5 and Pichia stipitis CBS6054.  

PubMed

Saccharomyces cerevisiae Y5 (CGMCC no. 2660) and Issatchenkia orientalis Y4 (CGMCC no. 2159) were combined individually with Pichia stipitis CBS6054 to establish the cocultures of Y5 + CBS6054 and Y4 + CBS6054. The coculture Y5 + CBS6054 effectively metabolized furfural and HMF and converted xylose and glucose mixture to ethanol with ethanol concentration of 16.6?g/L and ethanol yield of 0.46?g ethanol/g sugar, corresponding to 91.2% of the maximal theoretical value in synthetic medium. Accordingly, the nondetoxified dilute-acid hydrolysate was used to produce ethanol by co-culture Y5 + CBS6054. The co-culture consumed glucose along with furfural and HMF completely in 12?h, and all xylose within 96?h, resulting in a final ethanol concentration of 27.4?g/L and ethanol yield of 0.43?g ethanol/g sugar, corresponding to 85.1% of the maximal theoretical value. The results indicated that the co-culture of Y5 + CBS6054 was a satisfying combination for ethanol production from non-detoxified dilute-acid lignocellulosic hydrolysates. This co-culture showed a promising prospect for industrial application. PMID:22792472

Wan, Ping; Zhai, Dongmei; Wang, Zhen; Yang, Xiushan; Tian, Shen

2012-01-01

204

Ethanol Production from Nondetoxified Dilute-Acid Lignocellulosic Hydrolysate by Cocultures of Saccharomyces cerevisiae Y5 and Pichia stipitis CBS6054  

PubMed Central

Saccharomyces cerevisiae Y5 (CGMCC no. 2660) and Issatchenkia orientalis Y4 (CGMCC no. 2159) were combined individually with Pichia stipitis CBS6054 to establish the cocultures of Y5 + CBS6054 and Y4 + CBS6054. The coculture Y5 + CBS6054 effectively metabolized furfural and HMF and converted xylose and glucose mixture to ethanol with ethanol concentration of 16.6?g/L and ethanol yield of 0.46?g ethanol/g sugar, corresponding to 91.2% of the maximal theoretical value in synthetic medium. Accordingly, the nondetoxified dilute-acid hydrolysate was used to produce ethanol by co-culture Y5 + CBS6054. The co-culture consumed glucose along with furfural and HMF completely in 12?h, and all xylose within 96?h, resulting in a final ethanol concentration of 27.4?g/L and ethanol yield of 0.43?g ethanol/g sugar, corresponding to 85.1% of the maximal theoretical value. The results indicated that the co-culture of Y5 + CBS6054 was a satisfying combination for ethanol production from non-detoxified dilute-acid lignocellulosic hydrolysates. This co-culture showed a promising prospect for industrial application. PMID:22792472

Wan, Ping; Zhai, Dongmei; Wang, Zhen; Yang, Xiushan; Tian, Shen

2012-01-01

205

Headspace analysis of volatile metabolites of Pseudomonas aeruginosa and related species by gas chromatography-mass spectrometry.  

PubMed Central

Gas chromatographic-mass spectrometric analysis of headspace volatiles was performed on cultures of 11 strains of Pseudomonas aeruginosa and 1 strain each of Pseudomonas cepacia, Pseudomonas putida, Pseudomonas putrefaciens, Pseudomonas fluorescens, and Pseudomonas maltophilia. All strains of Pseudomonas aeruginosa produced a distinctive series of odd-carbon methyl ketones, particularly 2-nonanone and 2-undecanone, and 2-aminoacetophenone. The other strains failed to produce 2-aminoacetophenone. Two sulfur compounds, dimethyldisulfide and dimethyltrisulfide, were present in strains of P. aeruginosa and in variable amounts in other species. Butanol, 2-butanone, 1-undecene, and isopentanol were also detected in P. aeruginosa cultures. PMID:6775012

Labows, J N; McGinley, K J; Webster, G F; Leyden, J J

1980-01-01

206

The effects of washing upon the bacterial flora of the stallion prepuce  

E-print Network

. ~tr act* ggl Enterobacter spp. 1 a c*l 'PPFa o t ri pp. Klebsiella spp. pe o 1 M)crococcus spp. Proteus inconstans ~s gn Proteus spp. Proteus vulgaris pseupSomonas aeruginosa Psa a r q a s ( plq t d) Pseudomonas maltophilia PsNS* op p... pneumoniae d ?o?s spp. Proteus inconstans Proteus mirabilis ~ro eus spp. Proteus vulgaris P *d* es ~Po ganesa (no ptgm* t d) 'p er)o s ~p Pseudomonas spp. gttp ? s sPP. ( g 1 p ttt ) tap y ococcus spp. (coagulase negative) Streptococcus e uisimilis...

Tobin, Nancy Batterton

2012-06-07

207

Exploring characteristics of bioelectricity generation and dye decolorization of mixed and pure bacterial cultures from wine-bearing wastewater treatment  

Microsoft Academic Search

This study uncovered microbial characteristics of bioelectricity generation and dye decolorization in single-chamber microbial\\u000a fuel cells (MFCs) using activated sludge for wine-containing wastewater treatment. Phylogenetic tree analysis on 16S rRNA\\u000a gene fragments indicated that the predominant strains on anodic biofilm in acclimatized MFCs were Gamma-Proteobacteria Aeromonas punctata NIU-P9, Pseudomonas plecoglossicida NIU-Y3, Pseudomonas koreensis NIU-X8, Acinetobacter junii NIU-Y8, Stenotrophomonas maltophila NIU-X2.

Jing-Long Han; Ying Liu; Chang-Tang Chang; Bor-Yann Chen; Wen-Ming Chen; Hui-Zhong Xu

2011-01-01

208

Complete genome sequence of Kosakonia sacchari type strain SP1(T.).  

PubMed

Kosakonia sacchari sp. nov. is a new species within the new genus Kosakonia, which was included in the genus Enterobacter. K sacchari is a nitrogen-fixing bacterium named for its association with sugarcane (Saccharum officinarum L.). K sacchari bacteria are Gram-negative, aerobic, non-spore-forming, motile rods. Strain SP1(T) (=CGMCC1.12102(T)=LMG 26783(T)) is the type strain of the K sacchari sp. nov and is able to colonize and fix N2 in association with sugarcane plants, thus promoting plant growth. Here we summarize the features of strain SP1(T) and describe its complete genome sequence. The genome contains a single chromosome and no plasmids, 4,902,024 nucleotides with 53.7% GC content, 4,460 protein-coding genes and 105 RNA genes including 22 rRNA genes, 82 tRNA genes, and 1 ncRNA gene. PMID:25197499

Chen, Mingyue; Zhu, Bo; Lin, Li; Yang, Litao; Li, Yangrui; An, Qianli

2014-06-15

209

Phenylobacterium zucineum sp. nov., a facultative intracellular bacterium isolated from a human erythroleukemia cell line K562.  

PubMed

A bacterial strain HLK1(T) was isolated from the human erythroleukemia cell line K562. This bacterium is a Gram-negative rod, motile with a polar flagellum. It is strictly aerobic, nonfermentative, and oxidase and catalase positive. Its optimal growth occurs at 37 degrees C at pH between 6.5 and 7.5. Phylogenetically, although it shares 98% similarity with the 16S rRNA of Phenylobacterium lituiforme, the DNA-DNA hybridization value between the two species is only 43%. HLK1(T) has a DNA G+C content of 71.2+/-0.2 mol%. It is a facultative intracellular organism and may have pathogenic relevance with humans and mammals. On the basis of the phylogenetic and phenotypic characterization, strain HLK1(T) is proposed to be classified in the genus Phenylobacterium, as P. zucineum sp. nov. The type strain is HLK1(T) (=CGMCC 1.3786(T), DSM=18354). PMID:16908113

Zhang, Kun; Han, Weidong; Zhang, Rong; Xu, Xiaoli; Pan, Qiangrong; Hu, Xun

2007-04-01

210

Efficient production of dihydroxyacetone from biodiesel-derived crude glycerol by newly isolated Gluconobacter frateurii.  

PubMed

The efficient production of dihydroxyacetone (DHA) on biodiesel-derived glycerol based media was developed. A newly isolated strain, Gluconobacter frateurii CGMCC 5397, could convert crude glycerol to DHA with high yield and productivity. In shake-flask fermentation, the DHA concentration of 73.1 gl(-1) was attained at 48 h using an optimum medium containing biodiesel-derived crude glycerol. When fed-batch fermentation was carried out in a 7-l stirred bioreactor with crude glycerol, the DHA concentration, productivity, and yield were 125.8 gl(-1), 2.6 gl(-1)h(-1), and 90.5% at 48 h, respectively. This study suggests that the inexpensive biodiesel-derived crude glycerol could be utilized for efficient production of DHA by G. frateurii. PMID:23748086

Liu, Yu-Peng; Sun, Yang; Tan, Cong; Li, Hua; Zheng, Xiao-Juan; Jin, Kui-Qi; Wang, Gang

2013-08-01

211

Evaluation of the formation of volatiles and sensory characteristics of persimmon (Diospyros kaki L.f.) fruit wines using different commercial yeast strains of Saccharomyces cerevisiae.  

PubMed

This study evaluated the effects of five strains (IFFI 1346, IFFI 1363, CICC 31482, D254 and CGMCC2.346) of the yeast Saccharomyces cerevisiae on the aromatic profiles of fermented persimmon (Diospyros kaki L.f.) musts. A total of 50 and 60 compounds were identified in persimmon wine by stir bar sorptive extraction coupled with gas chromatography-mass spectrometry. According to odour activity values (OAVs), 26 detected compounds showed an OAV above 1. Principal component analysis explained the distribution of these persimmon wines on the basis of volatile compounds with OAV>1. The volatile compounds with high OAV included ethyl hexanoate, ethyl octanoate, methyl decanoate, linalool and geraniol. Quantitative descriptive analysis was employed. The result showed that persimmon wines fermented with strains IFFI 1363 and D254 were strongly correlated with persimmon, aroma harmony, fruity, fusel and taste balanced, fullness, hedonic scale. Therefore, the two yeast strains could be used as starter culture for persimmon wine production. PMID:25186058

Zhu, Jian Cai; Niu, Yun Wei; Feng, Tao; Liu, Sheng Jiang; Cheng, He Xing; Xu, Na; Yu, Hai Yan; Xiao, Zuo Bing

2014-11-01

212

Production of sophorolipids with eicosapentaenoic acid and docosahexaenoic acid from Wickerhamiella domercqiae var. sophorolipid using fish oil as a hydrophobic carbon source.  

PubMed

Sophorolipids (SLs) were synthesized by Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 grown on fish oil and glucose. They were purified using preparative HPLC and their structures were identified by MS/MS. The yields of total and lactonic SLs were 47 and 19 g l(-1) in shake-flasks when fish oil 4 % (v/v) was used with glucose in the medium. The composition of SL mixture contained more than 20 SL molecules. Several unconventional SL molecules with eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) including zero-, mono- and di-acetylated acidic SLs with EPA and a di-acetylated acidic SL with DHA were obtained. Two unconventional lactonic SL molecules, non-acetylated lactonic SL with 22:3 and non-acetylated lactonic SL with 20:0, were also obtained. PMID:23386226

Li, Hui; Ma, Xiao-Jing; Wang, Shuang; Song, Xin

2013-06-01

213

Prauserella shujinwangii sp. nov., from a desert environment.  

PubMed

A Gram-positive, spore-forming, rod-shaped actinomycete, designated XJ46(T), was isolated from Xinjiang Uyghur Autonomous Region, China and subjected to a polyphasic taxonomic analysis. Morphological and chemotaxonomic characteristics of XJ46(T) were identified as being similar to those of members of the genus Prauserella. The phylogenetic tree based on 16S rRNA gene sequences showed that XJ46(T) shared the highest similarity (95.9?%) with Prauserella marina MS498(T). Based on its phenotypic characteristics, chemotaxonomic analysis and 16S rRNA gene sequence analysis, strain XJ46(T) is proposed to represent a novel species of the genus Prauserella, named Prauserella shujinwangii sp. nov. The type strain is XJ46(T) (?=?CGMCC 4.7125(T)?=?JCM 19736(T)). PMID:25158847

Liu, Mei; Zhang, Li; Ren, Biao; Yang, Na; Yu, Xiaoyun; Wang, Jian; Ding, Linxian; Liu, Xueting; Liu, Zhiheng; Goodfellow, Michael; Zhang, Lixin

2014-11-01

214

Resistance of Bacillus subtilis spores to 12C ion beams, stimulation of high-energy charged particles in space  

NASA Astrophysics Data System (ADS)

To monitor the response of live microbes in space radiation environment with high-energy charged particles, we carry out ground stimulation radiation experiments. Spores of Bacillus (CGMCC 1.1849) species are one of the model systems used for astro- and radiobiological studies. (12) C ion beams served as stimulated space radiation from 5gry, 10gry, 20gry, 40gry, to 80gry at a rate of 15gry/min Death rates are measured and mutant strains are isolated. Five representative strains are analyzed for their corresponding gene sequences, protein sequences and gene expression index of DNA repair system gene recA and recO. The statistic results showed the strains resistance to (12) C ion beams radiation is partially due to the increase of gene expression index of recA and recO. In conclusion, our research provide a surrogate system to monitor the live microbial response in resistant to space radiation environment.

Zhang, Li; Dang, Bingrong; Li, Junxiong; Chen, Jinsong; Liu, Mei; Liu, Zhiheng; Zhang, Lixin

215

Salinimicrobium sediminis sp. nov., isolated from a deep-sea sediment.  

PubMed

Strain JC207(T) was isolated from a deep (265 m) sea sediment, and appeared as dark yellow colonies on agar plates with cells staining Gram-negative. Catalase, oxidase and caseinase were positive, while chitinase, gelatinase and amylase were negative. Major (>5?%) fatty acids were iso-C15?:?0, anteiso-C15:0, iso-C17?:?1?9c, iso-C16?:?0, iso-C15?:?0 3-OH, iso-C17?:?0 3-OH, iso-C14?:?0 and iso-C15:1G. Strain JC207(T) contained phosphatidylethanolamine as the major polar lipid, with minor amounts of five unidentified lipids. A bacterial hopane derivative, diplopterol and adenosylhopane were the major hopanoids. Genomic DNA G+C content was 47.5 mol%. 16S rRNA gene sequence comparisons indicated that strain JC207(T) represented a member of the genus Salinimicrobium within the family Flavobacteriaceae of the phylum Bacteroidetes. Strain JC207(T) had sequence similarity with Salinimicrobium terrae YIM-C338(T) (98%), Salinimicrobium xinjiangense BH206(T) (97.6?%) and other members of the genus Salinimicrobium (<96.8?%). However, strain JC207(T) showed an average of 23.6 ± 4 and 37 ± 4 relatedness (based on DNA-DNA hybridization) with Salinimicrobium terrae CGMCC 1.6308(T) (?=?YIM-C338(T)) and Salinimicrobium xinjiangense KCTC 12883(T) (?=?BH206(T)), respectively. Morphological, physiological and genotypic differences from the previously described taxa support the classification of strain JC207(T) as a representative of a novel species in the genus Salinimicrobium, for which the name Salinimicrobium sediminis sp. nov. is proposed. The type strain is JC207(T) (?=?KCTC 32444(T)?=?CGMCC 1.12641(T)). PMID:24425818

Subhash, Y; Sasikala, Ch; Ramana, Ch V

2014-03-01

216

Substrate utilization of stress tolerant methylotrophs isolated from revegetated heavy metal polluted coalmine spoil.  

PubMed

We analyzed methylotrophs in Bina natural vegetation (BNV), and revegetated overburden dump of four (ROBD4) and 12 years (ROBD12), at Bina coal mine in Sonbhadra district. The cultured strains identified as Pseudomonas, Acinetobacter, Stenotrophomonas and Cellvibrio (?-Proteobacteria), Methylophilus, Ralstonia, Burkholderia (?-Proteobacteria) Methylobacterium and Inquilinus (?-Proteobacteria), Bacillus (Firmicutes) and Flexibacter (Sphingobacteria) in their 16s rRNA gene sequence similarity. The strains differed in citrate, lactose, formate, urea and xylose utilization. Methanol utilization by Stenotrophomonas, Inquilinus, Cellvibrio and Flexibacter is for first time. The preferred N- sources were proline, glutamate and nitrate for most of the strains. All strains tolerated (2.5 % NaCl) and SDS (0.2 %); 16 strains survived in crystal violet (0.01 %) and nine strains in sodium azide (0.02 %. Methylotrophic population trend was BNV > ROBD12 > ROBD4. The presence of majority of strain of BNV at ROBD12 and ROBD4 indicated restoration of soil methylotrophic functional diversity in revegetated dumps. PMID:23184579

Giri, D D; Shukla, P N; Ritu, Singh; Kumar, Ajay; Pandey, K D

2013-04-01

217

Restricted streptomycin use in apple orchards did not adversely alter the soil bacteria communities  

PubMed Central

Streptomycin has been authorized for restricted use in the prevention of the fire blight disease of pome fruit orchards in the EU and Switzerland. This study addresses the important topic of the influence of the use of streptomycin in agriculture on the total bacteria community within the soil ecosystem. Soil samples were taken from soils under apple trees, prior to streptomycin application and 2 weeks post streptomycin application or water application (untreated control). High throughput 16S rRNA gene amplicon sequencing was used to generate datasets from the soils under apple trees in apple orchards from three different locations in Switzerland. We hypothesized that the use of streptomycin would reduce the bacterial diversity within the soil samples and enhance a reduction in the variety of taxa present. Bacterial species such as Pseudomonas, Burkholderia, and Stenotrophomonas are intrinsically resistant to many antibiotics and as such it is of interest to investigate if the use of streptomycin provided a selective advantage for these bacteria in the soil ecosystem. The application of streptomycin did not influence the abundance and diversities of major bacteria taxa of the soils or the Pseudomonas, Burkholderia, and Stenotrophomonas species. We also discovered that apple orchards under the same management practices, did not harbor the same bacterial communities. The restricted application of streptomycin in the protection of apple orchards from the fire blight pathogen Erwinia amylovora under the guidelines in Switzerland did not alter either the bacterial diversity or abundance within these soil ecosystems. PMID:24550889

Walsh, Fiona; Smith, Daniel P.; Owens, Sarah M.; Duffy, Brion; Frey, Jürg E.

2014-01-01

218

Restricted streptomycin use in apple orchards did not adversely alter the soil bacteria communities.  

PubMed

Streptomycin has been authorized for restricted use in the prevention of the fire blight disease of pome fruit orchards in the EU and Switzerland. This study addresses the important topic of the influence of the use of streptomycin in agriculture on the total bacteria community within the soil ecosystem. Soil samples were taken from soils under apple trees, prior to streptomycin application and 2 weeks post streptomycin application or water application (untreated control). High throughput 16S rRNA gene amplicon sequencing was used to generate datasets from the soils under apple trees in apple orchards from three different locations in Switzerland. We hypothesized that the use of streptomycin would reduce the bacterial diversity within the soil samples and enhance a reduction in the variety of taxa present. Bacterial species such as Pseudomonas, Burkholderia, and Stenotrophomonas are intrinsically resistant to many antibiotics and as such it is of interest to investigate if the use of streptomycin provided a selective advantage for these bacteria in the soil ecosystem. The application of streptomycin did not influence the abundance and diversities of major bacteria taxa of the soils or the Pseudomonas, Burkholderia, and Stenotrophomonas species. We also discovered that apple orchards under the same management practices, did not harbor the same bacterial communities. The restricted application of streptomycin in the protection of apple orchards from the fire blight pathogen Erwinia amylovora under the guidelines in Switzerland did not alter either the bacterial diversity or abundance within these soil ecosystems. PMID:24550889

Walsh, Fiona; Smith, Daniel P; Owens, Sarah M; Duffy, Brion; Frey, Jürg E

2013-01-01

219

Numerical analysis of 295 phenotypic features of 266 Xanthomonas strains and related strains and an improved taxonomy of the genus.  

PubMed

An extensive phenotypic description and an improved classification and nomenclature of the genus Xanthomonas are presented. A total of 266 strains obtained from different geographical areas, including representative strains of all species of the genus Xanthomonas and most pathovars of Xanthomonas campestris, as well as strains which might be genetically related to the genus Xanthomonas, were examined for 295 morphological, biochemical, and physiological features. Similarities among the strains were expressed numerically by using the coefficient of Sokal and Michener. Clustering was performed by using the unweighted average pair group method. The conclusions described below were reached. (i) The genus Xanthomonas comprises at least the following eight phena: X. campestris, Xanthomonas albilineans, Xanthomonas axonopodis, Xanthomonas fragariae, Xanthomonas populi, Xanthomonas maltophilia, Xanthomonas oryzae Swings et al. 1990, and X. campestris pv. graminis Egli and Schmidt 1982 [not X. campestris pv. graminis (Egli et al. 1975) ISPP List 1980]. (ii) X. populi (Ridé 1958) Ridé and Ridé 1978 is a separate species. (iii) X. maltophilia Swings et al. 1983 forms a separate species. (iv) X. campestris pv. oryzae ISPP List 1980 can no longer be regarded as pathovar of X. campestris, and its recent reclassification as a new species, X. oryzae (Swings et al., Int. J. Syst. Bacteriol. 40:309-311, 1990), is supported. (v) X. campestris pv. graminis Egli and Schmidt 1982 [not X. campestris pv. graminis (Egli et al. 1975) ISPP List 1980] seems to form a separate complex of highly related pathovars obtained from members of the Poaceae; the taxonomic implications of this are discussed. (vi) Strains of nearly all X. campestris pathovars cluster together in the X. campestris phenon. Within this species we were able to differentiate some entities on phenotypic grounds; these groups sometimes corresponded to named pathovars (e.g., X. campestris pv. manihotis, X. campestris pv. cassavae, X. campestris pv. phlei). In several other cases, pathovars were found to be heterogeneous. (vii) A number of dubious Pseudomonas species were identified as members of or as being close to Xanthomonas species. Both Pseudomonas betle and Pseudomonas hibiscicola are synonyms of X. maltophilia. We also confirmed that Pseudomonas mangiferaeindicae, Pseudomonas vitiswoodrowii, and Pseudomonas gardneri belong to X. campestris. (viii) Forty phenotypic features allow the differentiation of the eight Xanthomonas phena. (ix) A number of additional features of the genera Xanthomonas and Xylophilus are described. PMID:2275852

Van den Mooter, M; Swings, J

1990-10-01

220

Bacteriocuprein superoxide dismutases in pseudomonads  

SciTech Connect

Two new instances of the rare bacteriocuprein form of superoxide dismutase have been discovered in Pseudomonas diminuta and P. maltophilia. Each species contains a manganese superoxide dismutase as well. Eight other strains of Pseudomonas and Xanthomonas spp. lacked bacteriocupreins and contained either a manganese or an iron superoxide dismutase. Native molecular weights and isoelectric points were determined for all these bacterial dismutases. A monospecific polyclonal antibody was prepared against the bacteriocuprein from Photobacterium leiognathi; it was not cross-reactive with the bacteriocuprein from either Pseudomonas strain. Bacteriocupreins have previously been identified in only two procaryotes, P. leiognathi and Caulobacter crescentus. The discovery of the Pseudomonas bacteriocupreins reveals a broader distribution, raising the possibility that bacteriocupreins are a continuous line of descent among procryotes and not isolated evolutionary occurrences, as previous data suggested.

Steinman, H.M.

1985-06-01

221

Flavobacterium aquaticum sp. nov., isolated from a water sample of a rice field.  

PubMed

Strain JC164(T) was isolated from a water sample from a rice field at Jamdih, Mau, Uttar Pradesh, India. Colonies of strain JC164(T) were brown-yellow and cells were Gram-stain-negative. Catalase, oxidase and amylase were present. iso-C(15:0), iso-C(16:0), iso-C15?1 G, iso-C(15:0) 3-OH and iso-C(14:0) were the predominant fatty acids with minor amounts of iso-C(16:0) 3-OH, anteiso-C(15:0), C(16:0), iso-C(16:1) H, iso-C(14:0) 3-OH and iso-C(13:0). Strain JC164(T) contained phosphatidylethanolamine and a few unidentified lipids (L1, L3 and L6) as major polar lipids. Bacteriohopane derivative 1 (BHD1) and diplopterol (DPL) were the major hopanoids. ?-Carotene was one among the several spirilloxanthin series carotenoids present in strain JC164(T). Genomic DNA G+C content was 39.6 mol%. 16S rRNA gene sequence comparisons indicated that strain JC164(T) represents a member of the genus Flavobacterium (family Flavobacteriaceae, class Flavobacteriia). The most closely related taxa to strain JC164(T) were Flavobacterium sasangense YC6274(T) (98.5%), Flavobacterium cucumis R2A45-3(T) (98.1%), Flavobacterium cheniae NJ-26(T) (97.2%) and the novel strain possessed <95.1% sequence similarity with other members of the genus Flavobacterium. However, strain JC164(T) showed 12.5 ± 2, 13.6 ± 1 and 17.4 ± 2% genomic DNA association (based on DNA-DNA hybridization) with Flavobacterium sasangense KCTC 22246(T), Flavobacterium cucumis DSM 18830(T) and Flavobacterium cheniae CGMCC 1.6844(T), respectively. The distinct genomic difference and morphological, physiological and chemotaxonomic differences from the previously described taxa support the classification of strain JC164(T) as a representative of a novel species of the genus Flavobacterium, for which the name Flavobacterium aquaticum sp. nov. is proposed. The type strain is JC164(T) (?=?KCTC 32196(T)?=?CGMCC 1.12398=LMG 27251(T)). PMID:23543500

Subhash, Y; Sasikala, Ch; Ramana, Ch V

2013-09-01

222

Bacillus beijingensis sp. nov. and Bacillus ginsengi sp. nov., isolated from ginseng root.  

PubMed

Four alkaligenous, moderately halotolerant strains, designated ge09, ge10(T), ge14(T) and ge15, were isolated from the internal tissue of ginseng root and their taxonomic positions were investigated by using a polyphasic approach. Cells of the four strains were Gram-positive-staining, non-motile, short rods. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains ge09 and ge10(T) formed one cluster and strains ge14(T) and ge15 formed another separate cluster within the genus Bacillus. 16S rRNA gene sequence similarities with type strains of other Bacillus species were less than 97 %. Levels of DNA-DNA relatedness among the four strains showed that strains ge09 and ge10(T) and strains ge14(T) and ge15 belonged to two separate species; the mean level of DNA-DNA relatedness between ge10(T) and ge14(T) was only 28.7 %. Their phenotypic and physiological properties supported the view that the two strains represent two different novel species of the genus Bacillus. The DNA G+C contents of strains ge10(T) and ge14(T) were 49.9 and 49.6 mol%, respectively. Strains ge10(T) and ge14(T) showed the peptidoglycan type A4alpha l-Lys-d-Glu. The lipids present in strains ge10(T) and ge14(T) were diphosphatidylglycerol, phosphatidylglycerol, a minor amount of phosphatidylcholine and two unknown phospholipids. Their predominant respiratory quinone was MK-7. The fatty acid profiles of the four novel strains contained large quantities of branched and saturated fatty acids. The predominant cellular fatty acids were iso-C(15 : 0) (42.5 %), anteiso-C(15 : 0) (22.2 %), anteiso-C(17 : 0) (7.3 %) and C(16 : 1)omega7c alcohol (5.7 %) in ge10(T) and iso-C(15 : 0) (50.7 %) and anteiso-C(15 : 0) (20.1 %) in ge14(T). On the basis of their phenotypic properties and phylogenetic distinctiveness, two novel species of the genus Bacillus are proposed, Bacillus beijingensis sp. nov. (type strain ge10(T) =DSM 19037(T) =CGMCC 1.6762(T)) and Bacillus ginsengi sp. nov. (type strain ge14(T) =DSM 19038(T) =CGMCC 1.6763(T)). PMID:19329597

Qiu, Fubin; Zhang, Xiaoxia; Liu, Lin; Sun, Lei; Schumann, Peter; Song, Wei

2009-04-01

223

Reclassification of Bacillus beijingensis Qiu et al. 2009 and Bacillus ginsengi Qiu et al. 2009 as Bhargavaea beijingensis comb. nov. and Bhargavaea ginsengi comb. nov. and emended description of the genus Bhargavaea.  

PubMed

We have carried out a polyphasic taxonomic characterization of Bacillus beijingensis DSM 19037(T) and Bacillus ginsengi DSM 19038(T), which are closely related phylogenetically to Bhargavaea cecembensis LMG 24411(T). All three strains are Gram-stain-positive, non-motile, moderately halotolerant and non-spore-forming. 16S rRNA gene sequence analyses showed that the strains constituted a coherent cluster, with sequence similarities between 99.7 and 98.7?%. The percentage similarity on the basis of amino acid sequences deduced from partial gyrB gene nucleotide sequences of these three type strains was 96.1-92.7?%. Phylogenetic trees based on the 16S rRNA gene and GyrB amino acid sequences, obtained by using three different algorithms, were consistent and showed that these three species constituted a deeply rooted cluster separated from the clades represented by the genera Bacillus, Planococcus, Planomicrobium, Sporosarcina, Lysinibacillus, Viridibacillus, Kurthia and Geobacillus, supporting their placement in the genus Bhargavaea. All three type strains have menaquinone MK-8 as the major respiratory quinone and showed similar fatty acid profiles. The main polar lipids present in the three type strains were diphosphatidylglycerol and phosphatidylglycerol, and the three strains showed peptidoglycan type A4? with L-lysine as the diagnostic diamino acid. The DNA G+C contents of Bacillus beijingensis DSM 19037(T), Bacillus ginsengi DSM 19038(T) and Bhargavaea cecembensis LMG 24411(T) were 53.1, 50.2 and 53.7 mol%, respectively. The level of DNA-DNA hybridization among the three strains was 57-39?%, indicating that they are members of different species of the genus Bhargavaea. The phenotypic data are consistent with the placement of these three species in a single genus and support their differentiation at the species level. On the basis of these data, we have emended the description of the genus Bhargavaea and propose the reclassification of Bacillus beijingensis and Bacillus ginsengi to the genus Bhargavaea, as Bhargavaea beijingensis comb. nov. (type strain ge10(T) ?=?DSM 19037(T) ?=?CGMCC 1.6762(T)) and Bhargavaea ginsengi comb. nov. (type strain ge14(T) ?=?DSM 19038(T) ?=?CGMCC 1.6763(T)). PMID:22155760

Verma, Pankaj; Pandey, Prashant Kumar; Gupta, Arvind Kumar; Seong, Chi Nam; Park, Seong Chan; Choe, Han Na; Baik, Keun Sik; Patole, Milind Shivaji; Shouche, Yogesh Shreepad

2012-10-01

224

Isolation and genetic identification of PAH degrading bacteria from a microbial consortium.  

PubMed

Polycyclic aromatic hydrocarbons (PAH; naphthalene, anthracene and phenanthrene) degrading microbial consortium C2PL05 was obtained from a sandy soil chronically exposed to petroleum products, collected from a petrochemical complex in Puertollano (Ciudad Real, Spain). The consortium C2PL05 was highly efficient degrading completely naphthalene, phenanthrene and anthracene in around 18 days of cultivation. The toxicity (Microtox method) generated by the PAH and by the intermediate metabolites was reduced to levels close to non-toxic in almost 40 days of cultivation. The identified bacteria from the contaminated soil belonged to gamma-proteobacteria and could be include in Enterobacter and Pseudomonas genus. DGGE analysis revealed uncultured Stenotrophomonas ribotypes as a possible PAH degrader in the microbial consortium. The present work shows the potential use of these microorganisms and the total consortium for the bioremediation of PAH polluted areas since the biodegradation of these chemicals takes place along with a significant decrease in toxicity. PMID:19468841

Molina, M Carmen; González, Natalia; Bautista, L Fernando; Sanz, Raquel; Simarro, Raquel; Sánchez, Irene; Sanz, José L

2009-11-01

225

Molecular characterization of nitrogen-fixing bacteria isolated from brazilian agricultural plants at S?o Paulo state  

PubMed Central

Fourteen strains of nitrogen-fixing bacteria were isolated from different agricultural plant species, including cassava, maize and sugarcane, using nitrogen-deprived selective isolation conditions. Ability to fix nitrogen was verified by the acetylene reduction assay. All potentially nitrogen-fixing strains tested showed positive hybridization signals with a nifH probe derived from Azospirillum brasilense. The strains were characterized by RAPD, ARDRA and 16S rDNA sequence analysis. RAPD analyses revealed 8 unique genotypes, the remaining 6 strains clustered into 3 RAPD groups, suggesting a clonal origin. ARDRA and 16S rDNA sequence analyses allowed the assignment of 13 strains to known groups of nitrogen-fixing bacteria, including organisms from the genera Azospirillum, Herbaspirillum, Pseudomonas and Enterobacteriaceae. Two strains were classified as Stenotrophomonas ssp. Molecular identification results from 16S rDNA analyses were also corroborated by morphological and biochemical data. PMID:24031239

Reinhardt, Erica. L.; Ramos, Patricia L.; Manfio, Gilson P.; Barbosa, Heloiza R.; Pavan, Crodowaldo; Moreira-Filho, Carlos A.

2008-01-01

226

Carbon utilization profiles of bacteria colonizing the headbox water of two paper machines in a Canadian mill.  

PubMed

Forty-one bacterial strains isolated from the headbox water of two machines in a Canadian paper mill were associated with the genera Asticcacaulis, Acidovorax, Bacillus, Exiguobacterium, Hydrogenophaga, Pseudomonas, Pseudoxanthomonas, Staphylococcus, Stenotrophomonas based on the sequence of their 16S rRNA genes. The metabolic profile of these strains were determined using Biolog EcoPlate, and the bacteria were divided into four metabolic groups. Metabolic profiles of the bacterial communities colonizing the headbox water of two paper machines was also determined weekly over a 1 year period. The only compound that was not reduced by the bacterial community was 2-hydroxybenzoic acid. Utilization frequency of the other carbon sources in the Biolog EcoPlate ranged from 3 to 100%. The metabolic profiles of the bacterial community did not vary considerably between the two paper machines. However, the metabolic profile varied among the sampling dates. PMID:19137341

Kashama, Johnny; Prince, Véronique; Simao-Beaunoir, Anne-Marie; Beaulieu, Carole

2009-03-01

227

Synthesis and structural characterization of Pd(II) complexes derived from perimidine ligand and their in vitro antimicrobial studies  

NASA Astrophysics Data System (ADS)

A novel series of Pd(II) complexes derived from 2-thiophenecarboxaldehyde and 1,8-diaminonaphthalene has been synthesized and characterized by various physico-chemical and spectroscopic techniques viz., elemental analyses, IR, UV-vis, 1H and 13C NMR spectroscopy, and ESI-mass spectrometry. The structure of ligand, 2-(2-thienyl)-2,3-dihydro-1H-perimidine has been ascertained on the basis of single crystal X-ray diffraction. All Pd(II) complexes together with the corresponding ligand have been evaluated for their ability to suppress the in vitro growth of microbes, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Citrobacter sp., Bacillus subtilis and Stenotrophomonas acidaminiphila and results show that Pd(II) complexes have more significant antimicrobial activity than their corresponding ligand. Fluorescence spectroscopic measurements clearly support that both of the Pd(II) complexes show significant DNA binding with calf thymus DNA.

Azam, Mohammad; Warad, Ismail; Al-Resayes, Saud I.; Alzaqri, Nabil; Khan, Mohammad Rizwan; Pallepogu, Raghavaiah; Dwivedi, Sourabh; Musarrat, Javed; Shakir, Mohammad

2013-09-01

228

ESTIMATING BACTERIAL DIVERSITY IN SCIRTOTHRIPS DORSALIS (THYSANOPTERA: THRIPIDAE) VIA NEXT GENERATION SEQUENCING  

PubMed Central

The last 2 decades have produced a better understanding of insect-microbial associations and yielded some important opportunities for insect control. However, most of our knowledge comes from model systems. Thrips (Thysanoptera: Thripidae) have been understudied despite their global importance as invasive species, plant pests and disease vectors. Using a culture and primer independent next-generation sequencing and metagenomics pipeline, we surveyed the bacteria of the globally important pest, Scirtothrips dorsalis Hood. The most abundant bacterial phyla identified were Actinobacteria and Proteobacteria and the most abundant genera were Propionibacterium, Stenotrophomonas, and Pseudomonas. A total of 189 genera of bacteria were identified. The absence of any vertically transferred symbiont taxa commonly found in insects is consistent with other studies suggesting that thrips primarilly acquire resident microbes from their environment. This does not preclude a possible beneficial/intimate association between S. dorsalis and the dominant taxa identified and future work should determine the nature of these associations. PMID:25382863

Dickey, Aaron M.; Trease, Andrew J.; Jara-Cavieres, Antonella; Kumar, Vivek; Christenson, Matthew K.; Potluri, Lakshmi-Prasad; Morgan, J. Kent; Shatters, Robert G.; Mckenzie, Cindy L.; Davis, Paul H.; Osborne, Lance S.

2014-01-01

229

The effects of Mary Rose conservation treatment on iron oxidation processes and microbial communities contributing to acid production in marine archaeological timbers.  

PubMed

The Tudor warship the Mary Rose has reached an important transition point in her conservation. The 19 year long process of spraying with polyethylene glycol (PEG) has been completed (April 29(th) 2013) and the hull is air drying under tightly controlled conditions. Acidophilic bacteria capable of oxidising iron and sulfur have been previously identified and enriched from unpreserved timbers of the Mary Rose, demonstrating that biological pathways of iron and sulfur oxidization existed potentially in this wood, before preservation with PEG. This study was designed to establish if the recycled PEG spray system was a reservoir of microorganisms capable of iron and sulfur oxidization during preservation of the Mary Rose. Microbial enrichments derived from PEG impregnated biofilm collected from underneath the Mary Rose hull, were examined to better understand the processes of cycling of iron. X-ray absorption spectroscopy was utilised to demonstrate the biological contribution to production of sulfuric acid in the wood. Using molecular microbiological techniques to examine these enrichment cultures, PEG was found to mediate a shift in the microbial community from a co-culture of Stenotrophomonas and Brevunidimonas sp, to a co-culture of Stenotrophomonas and the iron oxidising Alicyclobacillus sp. Evidence is presented that PEG is not an inert substance in relation to the redox cycling of iron. This is the first demonstration that solutions of PEG used in the conservation of the Mary Rose are promoting the oxidation of ferrous iron in acidic solutions, in which spontaneous abiotic oxidation does not occur in water. Critically, these results suggest PEG mediated redox cycling of iron between valence states in solutions of 75% PEG 200 and 50% PEG 2000 (v/v) at pH 3.0, with serious implications for the future use of PEG as a conservation material of iron rich wooden archaeological artefacts. PMID:24586230

Preston, Joanne; Smith, Andrew D; Schofield, Eleanor J; Chadwick, Alan V; Jones, Mark A; Watts, Joy E M

2014-01-01

230

Characterization of Co(III) EDTA-Reducing Bacteria in Metal- and Radionuclide-Contaminated Groundwater  

SciTech Connect

The Waste Area Grouping 5 (WAG5) site at Oak Ridge National Laboratory has a potential to be a field site for evaluating the effectiveness of various bioremediation approaches and strategies. The site has been well studied in terms of its geological and geochemical properties over the past decade. However, despite the importance of microorganisms in bioremediation processes, the microbiological populations at the WAG5 site and their potential in bioremediation have not been similarly evaluated. In this study, we initiated research to characterize the microbial populations in WAG5 groundwater. Approximately 100 isolates from WAG5 groundwater were isolated and selected based on colony morphology. Fifty-five unique isolates were identified by BOX-PCR and subjected to further characterization. 16S rRNA sequences indicated that these isolates belong to seventeen bacterial genera including Alcaligenes (1 isolate), Aquamonas (1), Aquaspirillum (1), Bacillus (10), Brevundimonas (5), Caulobacter (7), Dechloromonas (2), Janibacter (1), Janthinobacterium (2), Lactobacillus (1), Paenibacillus (4), Pseudomonas (9), Rhodoferax (1), Sphingomonas (1), Stenotrophomonas (6), Variovorax (2), and Zoogloea (1). Metal respiration assays identified several isolates, which phylogenically belong or are close to Caulobacter, Stenotrophomonas, Bacillus, Paenibacillus and Pseudomonas, capable of reducing Co(III)EDTA- to Co(II)EDTA{sup 2-} using the defined M1 medium under anaerobic conditions. In addition, using WAG5 groundwater directly as the inoculants, we found that organisms associated with WAG5 groundwater can reduce both Fe(III) and Co(III) under anaerobic conditions. Further assays were then performed to determine the optimal conditions for Co(III) reduction. These assays indicated that addition of various electron donors including ethanol, lactate, methanol, pyruvate, and acetate resulted in metal reduction. These experiments will provide useful background information for future bioremediation field experiments at the WAG5 site.

Gao, Weimin [Arizona State University; Gentry, Terry J [ORNL; Mehlhorn, Tonia L [ORNL; Carroll, Sue L [ORNL; Jardine, Philip M [ORNL; Zhou, Jizhong [University of Oklahoma, Norman

2010-01-01

231

Wastewater irrigation increases the abundance of potentially harmful gammaproteobacteria in soils in Mezquital Valley, Mexico.  

PubMed

Wastewater contains large amounts of pharmaceuticals, pathogens, and antimicrobial resistance determinants. Only a little is known about the dissemination of resistance determinants and changes in soil microbial communities affected by wastewater irrigation. Community DNAs from Mezquital Valley soils under irrigation with untreated wastewater for 0 to 100 years were analyzed by quantitative real-time PCR for the presence of sul genes, encoding resistance to sulfonamides. Amplicon sequencing of bacterial 16S rRNA genes from community DNAs from soils irrigated for 0, 8, 10, 85, and 100 years was performed and revealed a 14% increase of the relative abundance of Proteobacteria in rainy season soils and a 26.7% increase in dry season soils for soils irrigated for 100 years with wastewater. In particular, Gammaproteobacteria, including potential pathogens, such as Pseudomonas, Stenotrophomonas, and Acinetobacter spp., were found in wastewater-irrigated fields. 16S rRNA gene sequencing of 96 isolates from soils irrigated with wastewater for 100 years (48 from dry and 48 from rainy season soils) revealed that 46% were affiliated with the Gammaproteobacteria (mainly potentially pathogenic Stenotrophomonas strains) and 50% with the Bacilli, whereas all 96 isolates from rain-fed soils (48 from dry and 48 from rainy season soils) were affiliated with the Bacilli. Up to six types of antibiotic resistance were found in isolates from wastewater-irrigated soils; sulfamethoxazole resistance was the most abundant (33.3% of the isolates), followed by oxacillin resistance (21.9% of the isolates). In summary, we detected an increase of potentially harmful bacteria and a larger incidence of resistance determinants in wastewater-irrigated soils, which might result in health risks for farm workers and consumers of wastewater-irrigated crops. PMID:24951788

Broszat, Melanie; Nacke, Heiko; Blasi, Ronja; Siebe, Christina; Huebner, Johannes; Daniel, Rolf; Grohmann, Elisabeth

2014-09-01

232

Kroppenstedtia guangzhouensis sp. nov., a thermoactinomycete isolated from soil.  

PubMed

A Gram-stain-positive, spore-forming, aerobic and filamentous thermoactinomycete, designated GD02(T), was isolated from soil in south China. The isolate could grow in the presence of 0-3.0?% NaCl (w/v), at temperatures of 30-60 °C and at pH 5.5-9.5, forming ivory-coloured colonies. When the 16S rRNA gene sequence of the isolate was compared with those of other bacteria, the highest similarity was observed with Kroppenstedtia eburnea DSM 45196(T) (96.1?% 16S rRNA gene sequence similarity). The G+C content of the genomic DNA was 56.3 mol%, the cell-wall peptidoglycan contained ll-diaminopimelic acid, the main polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine and phosphatidylglycerol, and the major menaquinone was MK-7. The major cellular fatty acids (>5?%) were iso-C15?:?0, iso-C16?:?0, iso-C17?:?0 and anteiso-C15?:?0. On the basis of its phenotypic and phylogenetic properties, chemotaxonomic analysis and the results of physiological and biochemical tests, strain GD02(T) (?=?CGMCC 1.12404(T)?=?KCTC 29149(T)) was designated the type strain of a novel species of the genus Kroppenstedtia, for which the name Kroppenstedtia guangzhouensis sp. nov. is proposed. PMID:23728375

Yang, Guiqin; Qin, Dongxing; Wu, Chu; Yuan, Yong; Zhou, Shungui; Cai, Yanfei

2013-11-01

233

Performance of a new thermostable mannanase in breaking guar-based fracturing fluids at high temperatures with little premature degradation.  

PubMed

A new thermostable ?-1,4-mannanase (DtManB) cloned from Dictyoglomus thermophilum CGMCC 7283 showed the maximum activity towards hydroxypropyl guar gum at 80 °C, with a half-life of 46 h. DtManB exhibited good compatibility with various additives of fracturing fluid, retaining more than 50 % activity in all the cases tested. More importantly, premature degradation could be alleviated significantly when using DtManB as breaker, because at 27 and 50 °C it displayed merely 3.7 and 18.5 % activities compared to those at 80 °C. In a static test, 0.48 mg DtManB could break 200 mL borax cross-linked fracturing fluid dramatically at 80 °C, and merely 18 mPa s of the viscosity was detected even after the broken fluid was cooled down and only 161.4 mg L(-1) of the residue was left after the enzymatic reaction. All these positive features demonstrate the great potential of this mannanase as a new enzyme breaker for application in enhanced recovery of petroleum oil. PMID:24150905

Hu, Ke; Li, Chun-Xiu; Pan, Jiang; Ni, Yan; Zhang, Xiao-Yan; Xu, Jian-He

2014-02-01

234

Streptomyces heilongjiangensis sp. nov., a novel actinomycete that produces borrelidin isolated from the root surface of soybean [Glycine max (L.) Merr  

PubMed Central

A borrelidin-producing actinomycete, designated strain NEAU-W2T, was isolated from the root surface of soybean [Glycine max (L.) Merr] and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of streptomycetes. The G+C content of the DNA was 66.12 mol%. Analysis of the 16S rRNA gene sequence of strain NEAU-W2T revealed that the strain formed a distinct clade within the 16S rRNA gene sequence phylogenetic tree and showed highest similarity (99.61?%) to Streptomyces neyagawaensis ATCC 27449T. However, the DNA–DNA relatedness between strain NEAU-W2T and S. neyagawaensis ATCC 27449T was 58.51?%. Strain NEAU-W2T could also be differentiated from S. neyagawaensis ATCC 27449T and other Streptomyces species showing high 16S rRNA gene sequence similarity (98–99?%), as well as other borrelidin-producing strains, based on morphological and physiological characteristics. On the basis of its physiological and molecular properties, it is proposed that strain NEAU-W2T represents a novel Streptomyces species, Streptomyces heilongjiangensis sp. nov. The type strain is NEAU-W2T (?=?CGMCC 4.7004T ?=?ATCC BAA-2424T ?=?DSM 42073T). PMID:22707527

Liu, Chongxi; Wang, Xiangjing; Yan, Yijun; Wang, Jidong; Zhang, Bo; Zhang, Ji

2013-01-01

235

Actinoalloteichus nanshanensis sp. nov., isolated from the rhizosphere of a fig tree (Ficus religiosa).  

PubMed

A Gram-positive, aerobic actinomycete, designated strain NEAU 119(T), was isolated from the rhizosphere of a fig tree and was characterized using a polyphasic approach. The isolate formed branching, non-fragmenting vegetative hyphae and produced black pigment on yeast extract/malt extract (ISP medium 2). The G+C content of the DNA was 76.6 mol%. The organism had chemotaxonomic characteristics typical of the genus Actinoalloteichus and was closely related to the type strains of Actinoalloteichus cyanogriseus, Actinoalloteichus spitiensis and Actinoalloteichus hymeniacidonis, currently the only three recognized species of the genus Actinoalloteichus, sharing 16S rRNA gene similarities of 96.4, 96.6 and 98.1 %, respectively. However, the results of DNA-DNA hybridization studies demonstrated that the novel strain showed only 46.8 % relatedness with the type strain of A. hymeniacidonis. In addition, a set of phenotypic characteristics also readily distinguished strain NEAU 119(T) from the type strains of recognized species of the genus Actinoalloteichus. According to the above data, it is proposed that strain NEAU 119(T) represents a novel species, Actinoalloteichus nanshanensis sp. nov. The type strain of Actinoalloteichus nanshanensis is NEAU 119(T) (?=?CGMCC 4.5714(T)?=?NBRC 106685(T)). PMID:20562245

Xiang, Wensheng; Liu, Chongxi; Wang, Xiangjing; Du, Jing; Xi, Lijun; Huang, Ying

2011-05-01

236

Nonomuraea solani sp. nov., an actinomycete isolated from eggplant root (Solanum melongena L.)  

PubMed Central

A novel actinomycete, designated strain NEAU-Z6T, was isolated from eggplant (Solanum melongena L.) root. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain NEAU-Z6T belonged to the genus Nonomuraea, with highest sequence similarity to Nonomuraea monospora PT 708T (98.83?%), Nonomuraea rosea GW 12687T (98.55?%) and Nonomuraea rhizophila YIM 67092T (98.02?%). Sequence similarities between strain NEAU-Z6T and other species of the genus Nonomuraea ranged from 97.94?% (Nonomuraea candida HMC10T) to 96.30?% (Nonomuraea wenchangensis 210417T). Key morphological, physiological and chemotaxonomic characteristics of strain NEAU-Z6T were congruent with the description of the genus Nonomuraea. The G+C content of the genomic DNA was 64.51 mol%. DNA–DNA relatedness and comparative analysis of physiological, biochemical and chemotaxonomic data allowed genotypic and phenotypic differentiation of strain NEAU-Z6T from closely related species. Thus, strain NEAU-Z6T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea solani sp. nov. is proposed. The type strain is NEAU-Z6T (?=?CGMCC 4.7037T?=?DSM 45729T). PMID:23203622

Wang, Xiangjing; Zhao, Junwei; Liu, Chongxi; Wang, Jidong; Shen, Yue; Jia, Feiyu; Wang, Liang; Zhang, Ji; Yu, Chao

2013-01-01

237

Understanding of how Propionibacterium acidipropionici respond to propionic acid stress at the level of proteomics  

PubMed Central

Propionic acid (PA) is an important platform chemical in the food, agriculture, and pharmaceutical industries and is mainly biosynthesized by propionibacteria. Acid tolerance in PA-producing strains is crucial. In previous work, we investigated the acid tolerance mechanism of Propionibacterium acidipropionici at microenvironmental levels by analyzing physiological changes in the parental strain and three PA-tolerant mutants obtained by genome shuffling. However, the molecular mechanism of PA tolerance in P. acidipropionici remained unclear. Here, we performed a comparative proteomics study of P. acidipropionici CGMCC 1.2230 and the acid-tolerant mutant P. acidipropionici WSH1105; MALDI-TOF/MS identified 24 proteins that significantly differed between the parental and shuffled strains. The differentially expressed proteins were mainly categorized as key components of crucial biological processes and the acid stress response. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used to confirm differential expression of nine key proteins. Overexpression of the secretory protein glyceraldehyde-3-phosphate dehydrogenase and ATP synthase subunit ? in Escherichia coli BL21 improved PA and acetic acid tolerance; overexpression of NADH dehydrogenase and methylmalonyl-CoA epimerase improved PA tolerance. These results provide new insights into the acid tolerance of P. acidipropionici and will facilitate the development of PA production through fermentation by propionibacteria. PMID:25377721

Guan, Ningzi; Shin, Hyun-dong; Chen, Rachel R.; Li, Jianghua; Liu, Long; Du, Guocheng; Chen, Jian

2014-01-01

238

Microbispora hainanensis sp. nov., isolated from rhizosphere soil of Excoecaria agallocha in a mangrove.  

PubMed

Strain 211020(T) was isolated from rhizosphere soil of Excoecaria agallocha in a mangrove in Hainan, China. The strain produced longitudinal pair spores branching from aerial hyphae. 16S rRNA gene sequence analysis showed that the isolate belonged to the genus Microbispora, exhibiting the highest 16S rRNA gene sequence similarity (98.75?%) to Microbispora corallina JCM 10267(T) with a low DNA-DNA relatedness value (13 ± 0.6?%). The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid but madurose was not detected. The predominant menaquinones were MK-9(H(4)), MK-9(H(2)) and MK-9(H(0)), and the major fatty acids were iso-C(16?:?0), iso-C(15?:?0) and C(17?:?0). The phospholipid profile of strain 211020(T) comprised phosphatidylinositol mannoside, phosphatidylethanolamine, diphosphatidylglycerol and phospholipids of unknown structure containing glucosamine. The DNA G+C content was 70.8 mol%. On the basis of phenotypic and genotypic data, strain 211020(T) can be distinguished as a novel species of the genus Microbispora, for which the name Microbispora hainanensis sp. nov., is proposed. The type strain is 211020(T) (?=?CGMCC 4.5595(T)?=?DSM 45428(T)). PMID:22140174

Xu, Xiao-Xiong; Wang, Hai-Long; Lin, Hai-Peng; Wang, Cheng; Qu, Zhi; Xie, Qing-Yi; Ruan, Ji-Sheng; Hong, Kui

2012-10-01

239

Asymmetric synthesis of duloxetine intermediate (S)-(-)-3-N-methylamino-1-(2-thienyl)-1-propanol using immobilized Saccharomyces cerevisiae in liquid-core sodium alginate/chitosan/sodium alginate microcapsules.  

PubMed

Duloxetine intermediate (S)-(-)-3-N-methylamino-1-(2-thienyl)-1-propanol was synthesized using ACA liquid-core immobilized Saccharomyces cerevisiae CGMCC No. 2230. The optimum culture time for ACA liquid-core immobilized cells was found to be 28 h. The optimum ACA liquid-core capsule formation conditions were found to be 90 % chitosan deacetylation, 30,000-50,000 chitosan molecular weight, 5.0 g/L chitosan, and pH 6.0 citrate buffer solution. The highest activity was found when reduction conditions were pH 6.0, 30 °C and 180 rpm. The ACA-immobilized cells can be reused nine times and only 40 % of the activity is retained after nine cycles. Product inhibition of reduction was observed in batch reduction. Continuous reduction in the membrane reactor was found to remove the product inhibition on reduction and improve production capacity. Conversion reached 100 % and enantiometric excess of (S)-(-)-3-N-methylamino-1-(2-thienyl)-1-propanol exceeded 99.0 % in continuous reduction of 5 g/L 3-N-methylamino-1-(2-thienyl)-1-propanone in the membrane reactor. PMID:24798376

Zhimin, Ou; Haibing, Zhao; Lan, Tang; Wei, Zhang; Gensheng, Yang

2014-11-01

240

Description of Chishuiella changwenlii gen. nov., sp. nov., isolated from freshwater, and transfer of Wautersiella falsenii to the genus Empedobacter as Empedobacter falsenii comb. nov.  

PubMed

A Gram-reaction-negative, strictly aerobic, non-pigmented, non-gliding, rod-shaped bacterium, designated strain BY4(T), was isolated from freshwater. Cells were catalase- and oxidase-positive and indole was produced. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain BY4(T) belonged to the family Flavobacteriaceae and showed 91.6-95.9% sequence similarities to the most closely related strains. The major respiratory quinone was MK-6 and the major polar lipid was phosphatidylethanolamine. The major polyamine was homospermidine and the major fatty acids were iso-C(15?:?0), iso-C(17?:?0) 3-OH and summed feature 3 (C(16?:?1)?7c and/or C(16?:?1)?6c). The DNA G+C content was 30.0 mol%. On the basis of phenotypic, phylogenetic and genotypic features, strain BY4(T) is suggested to represent a novel species in a new genus within the family Flavobacteriaceae, for which the name Chishuiella changwenlii gen. nov., sp. nov. is proposed. The type strain of this type species is BY4(T) (?=?CGMCC 1.12707(T)?=?JCM 19633(T)). On the basis of data collected from previous and present studies, it is proposed to reclassify Wautersiella falsenii to the genus Empedobacter as the new combination Empedobacter falsenii comb. nov. (type strain NF 993(T)?=?CCUG 51536(T)?=?CIP 108861(T)). PMID:24844262

Zhang, Ren-Gang; Tan, Xu; Liang, Ye; Meng, Tian-Yi; Liang, Hui-Zhen; Lv, Jie

2014-08-01

241

Altuibacter lentus gen. nov., sp. nov., a novel member of family Flavobacteriaceae isolated from deep seawater of the South China Sea.  

PubMed

A novel chemoheterotrophic, aerobic, Gram-negative, rod-shaped, yellow-pigmented, bacterial strain JLT2010(T) was isolated from deep seawater of the South China Sea. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain JLT2010(T) belongs to the family Flavobacteriaceae and is most closely related to Ulvibacter antarcticus IMCC3101(T) with 95.7 % similarity. Some phenotypic characteristics such as the absence of flexirubin-type pigments, growth at 37 °C, hydrolysis of casein differentiated strain JLT2010(T) from the genus Ulvibacter as well as other genera in the family Flavobacteriaceae. The DNA G+C content of the strain JLT2010(T) was found to be 35.7 mol% and the major respiratory quinone was found to be MK-6. On the basis of phenotypic and phylogenetic features, JLT2010(T) is classified as a novel genus and species within the family Flavobacteriaceae, for which the name Altuibacter lentus gen. nov., sp. nov. is proposed. The type strain is JLT2010(T) (=JCM 18884(T) = CGMCC 1.12167(T)). PMID:24046207

Chen, Yi; Zhang, Zilian; Fu, Yingnan; Wang, Yanan; Wang, Yu; Jiao, Nianzhi

2013-12-01

242

Luteimonas cucumeris sp. nov., isolated a from cucumber leaf.  

PubMed

A Gram-negative, aerobic and non-motile rod, designated Y4(T), was isolated from a cucumber leaf from Pinggu District, east Beijing, PR China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain Y4(T) was most closely related to Luteimonas aquatica RIB1-20(T) (96.7% 16S rRNA gene sequence similarity). DNA-DNA relatedness between strain Y4(T) and L. aquatica RIB1-20(T) was 42.5 ± 3.9%. The predominant fatty acids were iso-C(15:0), iso-C(17:1)?9c, iso-C(16:0) and iso-C(17:0). The major ubiquinone was Q-8. The DNA G+C content of the type strain was 69.9 mol%. Based on the evidence above, strain Y4(T) represents a novel species of the genus Luteimonas, for which the name Luteimonas cucumeris sp. nov. is proposed. The type strain is Y4(T) (?= CGMCC 1.10821(T) = KCTC 23627(T)). PMID:22268071

Sun, Zhan-Bin; Zhang, Hui; Yuan, Xing-Fang; Wang, Yin-Xian; Feng, Dong-Mei; Wang, Yi-Hua; Feng, Yong-Jun

2012-12-01

243

Thermus arciformis sp. nov., a thermophilic species from a geothermal area.  

PubMed

Two aerobic, Gram-negative, non-motile, non-sporulating, yellow-pigmented bacteria, strains TH92(T) and TH91, were isolated from a hot spring located in Laibin, Guangxi, in the south-eastern geothermal area of China. The isolates grew at 40-77 degrees C (optimally at 70 degrees C) and at pH 6.0-9.5 (optimally at pH 7.5-8.0). Phylogenetic analysis of 16S rRNA gene sequences and levels of DNA-DNA relatedness together indicated that the new isolates represented a novel species of the genus Thermus with closest affinity to Thermus aquaticus, Thermus igniterrae and Thermus thermophilus. Compared with their closest relatives, strains TH92( T) and TH91 were able to assimilate a wider range of carbohydrates, amino acids and organic acids as sole carbon sources for growth, such as lactose and melibiose. The new isolates had lower combined levels of C(16 : 0 ) and iso-C(16 : 0) compared with their closest relatives. On the basis of polyphasic taxonomic characterization, strains TH92(T) and TH91 are considered to represent a single novel species of the genus Thermus, for which the name Thermus arciformis sp. nov. is proposed. The type strain is TH92(T) (=CGMCC 1.6992(T) =JCM 15153(T)). PMID:19661520

Zhang, Xin-Qi; Ying, Yi; Ye, Ying; Xu, Xue-Wei; Zhu, Xu-Fen; Wu, Min

2010-04-01

244

Diverse endophytic nitrogen-fixing bacteria isolated from wild rice Oryza rufipogon and description of Phytobacter diazotrophicus gen. nov. sp. nov.  

PubMed

Twenty-three nitrogen-fixing bacteria were isolated from surface-sterilized stems and roots of wild rice Oryza rufipogon. Four clusters were defined among these bacteria by SDS-PAGE protein patterns and further confirmed by IS-PCR finger-printing analysis. Phylogenetic analysis of 16S rRNA gene sequences showed that the representative strains LS 8 and LS 18 of cluster II formed a monophyletic group sharing 94.0-97.3% similarities with defined enterobacterial species within the genera Salmonella, Citrobacter, Pantoea, Klebsiella, and Enterobacter. DNA-DNA hybridization, physiological, biochemical tests, and cell morphology also revealed that these strains could be differentiated from the related enterobacterial species. Based upon these results, we propose Phytobacter diazotrophicus gen. nov., sp. nov. to the bacterial group represented by strains LS 8 and LS 18. The type strain is LS 8(T) (=DSM 17806(T) = LMG 23328(T) = CGMCC 1.5339(T)). The DNA G+C content of strain LS 8(T) is 58.6 +/- 0.5 mol%. PMID:18060384

Zhang, Guo Xia; Peng, Gui Xiang; Wang, En Tao; Yan, Hui; Yuan, Qing Hua; Zhang, Wu; Lou, Xu; Wu, Hui; Tan, Zhi Yuan

2008-05-01

245

Hymenobacter qilianensis sp. nov., isolated from a subsurface sandstone sediment in the permafrost region of Qilian Mountains, China and emended description of the genus Hymenobacter.  

PubMed

A red-pink, Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, designated strain DK6-37 was isolated from the permafrost region of Qilian Mountains in northwest of China. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that this isolate represents a novel member of the genus Hymenobacter, with low sequence similarities (<97 %) to recognized Hymenobacter species. Optimum growth was observed at 28 °C, pH 7.0 and 0 % NaCl. The strain was found to contain MK-7 as the predominant menaquinone. The polar lipids were identified as phosphatidylethanolanmine, two unknown aminophospholipids, one unknown aminolipid and three unknown polar lipids. The major fatty acids were identified as summed feature 3 (C16:1 ?7c/C16:1 ?6c as defined by MIDI), summed feature 4 (anteiso-C17:1 B/iso-C17:1 I), C16:1 ?5c, iso-C17:0 3-OH, iso-C15:0 and C18:0. The DNA G + C content was determined to be 67.4 mol %. On the basis of the polyphasic evidence presented, it is proposed that strain DK6-37 represents a novel species of the genus Hymenobacter, for which the name Hymenobacter qilianensis sp. nov. is proposed. The type strain is DK6-37(T) (= CGMCC 1.12720(T) = JCM 19763(T)). PMID:24677143

Han, Lu; Wu, Shu-Jiao; Qin, Chun-Yan; Zhu, You-Hai; Lu, Zhen-Quan; Xie, Bing; Lv, Jie

2014-05-01

246

Paenibacillus abyssi sp. nov., isolated from an abyssal sediment sample from the Indian Ocean.  

PubMed

A Gram-positive, rod-shaped bacterium, designated strain SCSIO N0306(T), was isolated from an abyssal sediment sample collected from the Indian Ocean. The isolate was found to grow optimally at 0-2 % (w/v) NaCl, pH 7.0 and 30 °C. Comparative analysis of the 16S rRNA gene sequence showed that the isolate SCSIO N0306(T) belongs phylogenetically to the genus Paenibacillus, and to be most closely related to P. algorifonticola XJ259(T) (with 95.47 % sequence similarity), sharing less than 95.0 % sequence similarity with all other taxa of this genus. Chemotaxonomic analysis revealed MK-7 as the major isoprenoid quinone, the DNA G+C content was determined to be 45.5 mol%, and anteiso-C15:0, C16:0, and iso-C15:0 were identified as the major fatty acids. On the basis of this polyphasic taxonomic data, isolate SCSIO N0306(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus abyssi sp. nov. is proposed. The type strain is SCSIO N0306(T) (= DSM 26238(T) = CGMCC 1.12987(T)). PMID:25249446

Huang, Xiao-Fang; Wang, Fa-Zuo; Zhang, Wei; Li, Jie; Ling, Juan; Yang, Jian; Dong, Jun-De; Tian, Xin-Peng

2014-12-01

247

Expression and characterization of dextransucrase gene dsrX from Leuconostoc mesenteroides in Escherichia coli.  

PubMed

The dextransucrase gene dsrX from Leuconostoc mesenteroides CGMCC 1.544 was cloned into the vector pET-28a(+) and expressed as a N-terminal His(6)-tag fusion protein of 167.57 kDa in Escherichia coli BL21(DE3). DsrX with the high volumetric activity of 8.8 U ml(-1) culture and the specific activity of 97.37 U mg(-1) crude enzyme extracts was measured in the optimized recombinant expression system. The resultant expression level of the fusion protein amounted to 24.5% of the total cell proteins. The results of affinity chromatography and western blotting indicated that the three sensitive sites of proteolysis existed in the N-terminal catalytic domain of DsrX. Both the recombinant and native enzyme activity were slightly activated by 1 mmol l(-1) Mn(2+) and strongly inhibited by 1 mmol l(-1) Cu(2+) or Al(3+), and their optimum pH values were 5.4. The optimum temperature of the recombinant enzyme for dextran synthesis was 30 degrees C, which was 10 degrees C less than that of the native one. The transglucosylation products of two enzymes were studied by using thin layer chromatography and high-performance anion exchange chromatography. It could be concluded that the better sample-pretreatment temperature in SDS-PAGE was 37 degrees C, which significantly improved the detection of thermal instable enzyme than that of 100 degrees C. PMID:18207273

Yalin, Yang; Jin, Luo; Jianhua, Wang; Da, Teng; Zigang, Tian

2008-02-29

248

Arcticibacter pallidicorallinus sp. nov. isolated from glacier ice.  

PubMed

A Gram-stain-negative, rod-shaped bacterium (strain Hh36(T)) was isolated from the No. 1 glacier in Xinjiang, north-west China. Colonies of strain Hh36(T) were pink, convex and round on PYG medium plates. Strain Hh36(T) was able to grow at 4-30 °C and pH 6.0-8.0. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Hh36(T) was related to members of the genus Arcticibacter. The major cellular fatty acids of the novel strain were iso-C15 : 0, summed feature 3 (C16 : 1?6c and/or C16 : 1?7c) and iso-C17 : 0 3-OH. The G+C content of the genomic DNA was 44.0 mol%. On the basis of phenotypic characteristics and phylogenetic analysis, strain Hh36(T) is considered to represent a novel species of the genus Arcticibacter, for which the name Arcticibacter pallidicorallinus sp. nov. is proposed. The type strain is Hh36(T) (?= CGMCC 1.9313(T) ?= KCTC 32542(T)). PMID:24711590

Liu, Qing; Kim, Song-gun; Liu, Hong-can; Xin, Yu-hua; Zhou, Yu-guang

2014-07-01

249

Streptohalobacillus salinus gen. nov., sp. nov., a moderately halophilic, Gram-positive, facultative anaerobe isolated from subsurface saline soil.  

PubMed

A Gram-stain-positive, rod-shaped, non-sporulating, motile and moderately halophilic bacterium, designated strain H96B60(T), was isolated from a saline soil sample of the Qaidam basin, China. The strain was facultatively anaerobic. Major end products formed from glucose fermentation were acetate, ethanol and lactic acid. The cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The isoprenoid quinone component was menaquinone-6 (MK-6). The predominant cellular fatty acids were C(16: 0), anteiso-C(13 : 0) and anteiso-C(15 : 0). The genomic DNA G+C content of strain H96B60(T) was 36.2 mol%. Phylogenetic analysis based on comparative 16S rRNA gene sequences indicated that strain H96B60(T) represented a novel phyletic lineage within the family Bacillaceae and was related most closely to Halolactibacillus species (96.1-96.4 % similarity). Based on the phenotypic, chemotaxonomic and phylogenetic data presented, strain H96B60(T) is considered to represent a novel species of a new genus, for which the name Streptohalobacillus salinus gen. nov., sp. nov. is proposed. The type strain of Streptohalobacillus salinus is H96B60(T) (?=?DSM 22440(T) ?=?CGMCC 1.7733(T)). PMID:20543154

Wang, Xiaowei; Xue, Yanfen; Ma, Yanhe

2011-05-01

250

Understanding of how Propionibacterium acidipropionici respond to propionic acid stress at the level of proteomics.  

PubMed

Propionic acid (PA) is an important platform chemical in the food, agriculture, and pharmaceutical industries and is mainly biosynthesized by propionibacteria. Acid tolerance in PA-producing strains is crucial. In previous work, we investigated the acid tolerance mechanism of Propionibacterium acidipropionici at microenvironmental levels by analyzing physiological changes in the parental strain and three PA-tolerant mutants obtained by genome shuffling. However, the molecular mechanism of PA tolerance in P. acidipropionici remained unclear. Here, we performed a comparative proteomics study of P. acidipropionici CGMCC 1.2230 and the acid-tolerant mutant P. acidipropionici WSH1105; MALDI-TOF/MS identified 24 proteins that significantly differed between the parental and shuffled strains. The differentially expressed proteins were mainly categorized as key components of crucial biological processes and the acid stress response. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used to confirm differential expression of nine key proteins. Overexpression of the secretory protein glyceraldehyde-3-phosphate dehydrogenase and ATP synthase subunit ? in Escherichia coli BL21 improved PA and acetic acid tolerance; overexpression of NADH dehydrogenase and methylmalonyl-CoA epimerase improved PA tolerance. These results provide new insights into the acid tolerance of P. acidipropionici and will facilitate the development of PA production through fermentation by propionibacteria. PMID:25377721

Guan, Ningzi; Shin, Hyun-Dong; Chen, Rachel R; Li, Jianghua; Liu, Long; Du, Guocheng; Chen, Jian

2014-01-01

251

Nonomuraea solani sp. nov., an actinomycete isolated from eggplant root (Solanum melongena L.).  

PubMed

A novel actinomycete, designated strain NEAU-Z6(T), was isolated from eggplant (Solanum melongena L.) root. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain NEAU-Z6(T) belonged to the genus Nonomuraea, with highest sequence similarity to Nonomuraea monospora PT 708(T) (98.83 %), Nonomuraea rosea GW 12687(T) (98.55 %) and Nonomuraea rhizophila YIM 67092(T) (98.02 %). Sequence similarities between strain NEAU-Z6(T) and other species of the genus Nonomuraea ranged from 97.94 % (Nonomuraea candida HMC10(T)) to 96.30 % (Nonomuraea wenchangensis 210417(T)). Key morphological, physiological and chemotaxonomic characteristics of strain NEAU-Z6(T) were congruent with the description of the genus Nonomuraea. The G+C content of the genomic DNA was 64.51 mol%. DNA-DNA relatedness and comparative analysis of physiological, biochemical and chemotaxonomic data allowed genotypic and phenotypic differentiation of strain NEAU-Z6(T) from closely related species. Thus, strain NEAU-Z6(T) represents a novel species of the genus Nonomuraea, for which the name Nonomuraea solani sp. nov. is proposed. The type strain is NEAU-Z6(T) ( = CGMCC 4.7037(T) = DSM 45729(T)). PMID:23203622

Wang, Xiangjing; Zhao, Junwei; Liu, Chongxi; Wang, Jidong; Shen, Yue; Jia, Feiyu; Wang, Liang; Zhang, Ji; Yu, Chao; Xiang, Wensheng

2013-07-01

252

Expression of POX2 gene and disruption of POX3 genes in the industrial Yarrowia lipolytica on the ?-decalactone production.  

PubMed

The yeast Yarrowia lipolytica growing on methyl ricinoleate can produce ?-decalactone, the worthy aroma compound, which can exhibit fruity and creamy sensorial notes, and recognized internationally as a safe food additive. Unfortunately, the yield is poor because of lactone degradation by enzyme Aox3 (POX3 gene encoded), which was responsible for continuation of oxidation after C(10) level and lactone reconsumption. In this paper, we chose the industrial Y. lipolytica (CGMCC accession number 2.1405), which is the diploid strain as the starting strain and constructed the recombinant strain Tp-12 by targeting the POX3 locus of the wild type, one copy of POX3 was deleted by CRF1+POX2 insertion. The other recombinant strain Tpp-11, which was a null mutant possessing multiple copies of POX2 and disrupted POX3 genes on two chromosomes, was constructed by inserting XPR2+hpt into the other copy of POX3 of Tp-12. The growth ability of the recombinants was changed after genetic modification in the fermentation medium. The production of ?-decalactone was increased, resulting from blocking ?-oxidation at the C(10) Aox level and POX2 overexpression. The recombinant strain Tpp-11 was stable. Because there was no reconsumption of ?-decalactone, the mutant strain could be grown in continuous fermentation of methyl ricinoleate to produce ?-decalactone. PMID:22115771

Guo, Yanqiong; Song, Huanlu; Wang, Zhaoyue; Ding, Yongzhi

2012-04-20

253

Bacterioplanes sanyensis gen. nov., sp. nov., a PHB-accumulating bacterium isolated from a pool of Spirulina platensis cultivation.  

PubMed

A Gram-negative, poly-3-hydroxybutyrate-accumulating rod bacterium, strain GYP-2(T), was isolated from a pool of marine Spirulina platensis cultivation, Sanya, China. Growth was observed at 10-45 °C and pH 6-10 in the presence of 1-10 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate belonged to Gammaproteobacteria and displayed 93.8-95.3 % 16S rRNA gene sequences similarities to members of the genera Thalassolituus, Oleibacter, and Oceanobacter, but house-keeping gene gyrB (encode DNA gyrase beta subunit) demonstrated that the new isolate was distantly related to Thalassolituus, Oleibacter, and Oceanobacter species (only 77-83 % gene gyrB sequences similarities).The G+C content of genomic DNA was 55 mol%. The major respiratory quinone was Q-9, while that for Oceanobacter kriegii LMG 6238(T) was Q-8. Major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. On the basis of its physiological, chemotaxonomic, and molecular properties, strain GYP-2(T) is suggested to represent a novel species of a new genus in Gammaproteobacteria, for which the name Bacterioplanes sanyensis gen. nov., sp. nov. is proposed. The type strain is GYP-2(T) (=CGMCC 1.12392(T)=KCTC 32220(T)). PMID:25038945

Wang, Guanghua; Jia, Qikun; Li, Tao; Dai, Shikun; Wu, Huanlian; He, Hui; Fan, Jiewei; Xiang, Wenzhou; Li, Xiang

2014-10-01

254

Paludibacter jiangxiensis sp. nov., a strictly anaerobic, propionate-producing bacterium isolated from rice paddy field.  

PubMed

A mesophilic, obligately anaerobic, propionate-producing fermentative bacterium, designated strain NM7(T), was isolated from rural rice paddy field. Cells of strain NM7(T) are Gram-negative, non-motile, non-spore-forming, short rods, and negative for catalase. The strain grew optimally at 37 °C (the range for growth 15-40 °C) and pH 7.0 (pH 5.0-7.5). The strain could grow fermentatively on various sugars, including arabinose, xylose, fructose, galactose, glucose, mannose, cellobiose, lactose, maltose, sucrose, pectin and starch. The main end products of glucose fermentation were acetate and propionate. Yeast extract was not required but stimulated the growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite, and Fe(III) nitrilotriacetate were not used as terminal electron acceptors. The G+C content of genomic DNA was 42.8 mol%. The major cellular fatty acids were C15:0, anteiso-C15:0, C16:0, and C17:0. The most abundant polar lipid of strain NM7(T) was phosphatidylethanolamine. 16S rRNA gene sequence analysis revealed that it belongs to the family Porphyromonadaceae of the phylum Bacteroidetes. The closest recognized species was Paludibacter propionicigenes (91.4 % similarity in 16S rRNA gene sequence). A novel species, Paludibacter jiangxiensis sp. nov., is proposed to accommodate strain NM7(T) (=JCM 17480(T) = CGMCC 1.5150(T) = KCTC 5844(T)). PMID:24419224

Qiu, Yan-Ling; Kuang, Xiao-Zhu; Shi, Xiao-Shuang; Yuan, Xian-Zheng; Guo, Rong-Bo

2014-03-01

255

Halococcus qingdaonensis sp. nov., a halophilic archaeon isolated from a crude sea-salt sample  

PubMed Central

A Gram-negative, extremely halophilic, coccoid archaeal strain, CM5T, was isolated from a crude sea-salt sample collected near Qingdao, China. The organism grew optimally at 35–40 °C and pH 6.0 in the presence of 20 % (w/v) NaCl. Its colonies were red in colour and it could use glucose as a sole carbon source for growth. The 16S rRNA gene sequence of CM5T was most closely related to those of Halococcus species. Its pattern of antibiotic susceptibility was similar to those of other described Halococcus species. Biochemical tests revealed no sign of H2S production or gelatin liquefaction. The main polar lipids of strain CM5T were phosphatidylglycerol, phosphatidylglycerol methylphosphate and sulfated diglycosyl diether. No phosphatidylglycerol sulfate was present. The DNA G+C content of strain CM5T was 61.2 mol% and it gave DNA–DNA reassociation values of 33.7, 57.1 and 29.6 %, respectively, with Halococcus salifodinae DSM 8989T, Halococcus dombrowskii DSM 14522T and Halococcus morrhuae ATCC 17082T. Based on its morphological and chemotaxonomic properties and phylogenetic analysis of 16S rRNA gene sequence data, we propose that CM5T should be classified within a novel species, Halococcus qingdaonensis sp. nov., with strain CM5T (=CGMCC 1.4243T=JCM 13587T) as the type strain. PMID:17329792

Wang, Qian-fu; Li, Wei; Yang, Hai; Liu, Yan-li; Cao, Hai-hua; Dornmayr-Pfaffenhuemer, Marion; Stan-Lotter, Helga; Guo, Guang-qin

2011-01-01

256

Catellatospora aurea sp. nov., a novel actinomycete isolated from soil.  

PubMed

A novel actinomycete, designated strain NEAU-SH16(T) was isolated from a soil sample collected from the riverbank of Wusong river in Shanghai and characterized using a polyphasic approach. Morphological and chemotaxonomic properties of strain NEAU-SH16(T) were consistent with the description of the genus Catellatospora. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that strain NEAU-SH16(T) formed a distinct branch with the closest relatives Catellatospora coxensis DSM 44901(T) (99.2 %) and Catellatospora citrea DSM 44097(T) (99.0 %), an association that was supported by a bootstrap value of 78 % in the neighbour-joining tree and also recovered with the maximum-likelihood algorithm. However, the low level of DNA-DNA relatedness and some different physiological characteristics allowed the strain to be distinguished from its closest relatives. Thus, it is proposed that strain NEAU-SH16(T) represents a novel Catellatospora species. Catellatospora aurea sp. nov. The type strain of Catellatospora aurea is NEAU-SH16(T) (=CGMCC 4.7147(T) = DSM 46719(T)). PMID:25261080

Liu, Chongxi; Zhao, Junwei; Guan, Xuejiao; Li, Lianjie; Li, Wenbin; Wang, Xiangjing; Xiang, Wensheng

2014-12-01

257

"Chemical nose" for the visual identification of emerging ocular pathogens using gold nanostars.  

PubMed

Ocular pathogens can cause serious damages in the eye leading to severe vision loss and even blindness if left untreated. Identification of pathogens is crucial for administering the appropriate antibiotics in order to gain effective control over ocular infection. Herein, we report a gold nanostar based "chemical nose" for visually identifying ocular pathogens. Using a spectrophotometer and nanostars of different sizes and degrees of branching, we show that the "chemical nose" is capable of identifying the following clinically relevant ocular pathogens with an accuracy of 99%: S. aureus, A. xylosoxidans, D. acidovorans and S. maltophilia. The differential colorimetric response is due to electrostatic aggregation of cationic gold nanostars around bacteria without the use of biomolecule ligands such as aptamers or antibodies. Transmission electron microscopy confirms that the number of gold nanostars aggregated around each bacterium correlates closely with the colorimetric response. Thus, gold nanostars serve as a promising platform for rapid visual identification of ocular pathogens with application in point-of-care diagnostics. PMID:24912040

Verma, Mohit S; Chen, Paul Z; Jones, Lyndon; Gu, Frank X

2014-11-15

258

Complex conductivity response to microbial growth and biofilm formation on phenanthrene spiked medium  

NASA Astrophysics Data System (ADS)

Several laboratory studies have recently demonstrated the utility of geophysical methods for the investigation of microbial-induced changes over contaminated sites. However, it remains difficult to distinguish the effects due to the new physical properties imparted by microbial processes, to bacterial growth, or to the development of bacterial biofilm. We chose to study the influence of biofilm formation on geophysical response using complex conductivity measurements (0.1-1000 Hz) in phenanthrene-contaminated media. Biotic assays were conducted with two phenanthrene (PHE) degrading bacterial strains: Burkholderia sp (NAH1), which produced biofilm and Stenophomonas maltophilia (MATE10), which did not, and an abiotic control. Results showed that bacterial densities for NAH1 and MATE10 strains continuously increased at the same rate during the experiment. However, the complex conductivity signature showed noticeable differences between the two bacteria, with a phase shift of 50 mrad at 4 Hz for NAH1, which produced biofilm. Biofilm volume was quantified by Scanning Confocal Laser Microscopy (SCLM). Significant correlations were established between phase shift decrease and biofilm volume for NAH1 assays. Results suggest that complex conductivity measurements, specifically phase shift, can be a useful indicator of biofilm formation inside the overall signal of microbial activity on contaminated sites.

Albrecht, Remy; Gourry, Jean Christophe; Simonnot, Marie-Odile; Leyval, Corinne

2011-11-01

259

60Co-irradiation as an alternate method for sterilization of penicillin G, neomycin, novobiocin, and dihydrostreptomycin  

SciTech Connect

The effects of the use of 60Co-irradiation to sterilize antibiotics were evaluated. The antibiotic powders were only occasionally contaminated with microorganisms. The D-values of the products and environmental isolates were 0.028, 0.027, 0.015, 0.046, 0.15, 0.018, and 0.19 Mrads for Aspergillus species (UC 7297, 7298), A. fumigatus (UC 7299), Rhodotorula species (UC 7300), Penicillium oxalicum (UC 7269), Pseudomonas maltophilia (UC 6855), and a biological indicator microorganism, Bacillus pumilus spores (ATCC 27142). An irradiation dose of 1.14 Mrads, therefore, was sufficient to achieve a six-log cycle destruction of B. pumilus spores. Based on the bioburden data, a minimum irradiation dose of 1.05 Mrads was calculated to be sufficient to obtain a 10(-6) probability of sterilizing the most radioresistant isolate, Pen. oxalicum. To determine the radiolytic degradation scheme and the stability of the antibiotics following irradiation, high-performance liquid chromatographic (HPLC) methods were developed. The resulting rates of degradation for the antibiotics were 0.6, 1.2, 2.3, and 0.95%/Mrad for penicillin G, neomycin, novobiocin, and dihydrostreptomycin, respectively. Furthermore, radiolytic degradation pathways for the antibiotics were identified and found to be similar to those commonly encountered when antibiotics are subjected to acidic, basic, hydrolytic, or oxidative treatments. No radiolytic compounds unique to 60Co-irradiation were found.

Tsuji, K.; Rahn, P.D.; Steindler, K.A.

1983-01-01

260

Seohaeicola nanhaiensis sp. nov., A Moderately Halophilic Bacterium Isolated from the Benthic Sediment of South China Sea.  

PubMed

An aerobic, Gram-staining negative, non-motile, and rod-shaped bacterial strain, SS011A0-7#2-2(T), was isolated from the sediment of South China Sea with the depth of 1,500 m. Optimum growth occurred at pH 8.0, 30 °C, and 6 % (w/v) NaCl. Strain SS011A0-7#2-2(T) did not synthesize bacteriochlorophyll a or carotenoid, neither possess photosynthesis genes. Its genome DNA G+C content was 67.9 mol%. It contained Q-10 as the predominant ubiquinone and C18:1 ?7c (52.3 %) as the major fatty acid. The major polar lipids were phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, unidentified phospholipid, and unidentified aminolipid. The 16S rRNA gene sequence analysis revealed that it was closely related to Seohaeicola saemankumensis SD-15(T), Phaeobacter gallaeciensis BS 107(T) and Roseovarius pacificus 81-2(T) in Rhodobacteraceae, with the 16S rRNA gene sequence similarities being 96.5, 95.7, and 95.6 %, respectively. However, the phylogeny of the 16S rRNA gene sequences revealed that strain SS011A0-7#2-2(T) was a member of the genus Seohaeicola. Strain SS011A0-7#2-2(T) was moderately halophilic which was different from Seohaeicola saemankumensis SD-15(T), and it showed the enzyme activities and carbon source spectrum significantly different from Seohaeicola saemankumensis SD-15(T). As its physiological and chemotaxinomic properties were different from those of Seohaeicola saemankumensis SD-15(T), strain SS011A0-7#2-2(T) represents a novel species of the genus Seohaecola. The name Seohaeicola nanhaiensis sp. nov. is proposed, with strain SS011A0-7#2-2(T) (=LMG 27733(T) = CGMCC 1.12759(T)) as the type strain. PMID:25027448

Xie, Bai-Sheng; Lv, Xiang-Lin; Cai, Man; Tang, Yue-Qin; Wang, Yan-Nan; Cui, Heng-Lin; Liu, Xue-Ying; Tan, Yan; Wu, Xiao-Lei

2014-12-01

261

Altererythrobacter oceanensis sp. nov., isolated from the Western Pacific.  

PubMed

A Gram-stain negative, ovoid-rod shaped, strictly aerobic bacterium, strain Y2(T), was isolated from a deep-sea sediment of the Western Pacific. Phylogenetic and phenotypic properties of the organism indicated that it belongs to the genus Altererythrobacter. Strain Y2(T) shares highest 16S rRNA gene sequence similarity of 96.6 % with Erythrobacter jejuensis CNU001(T), followed by the type strains of recognized members of the genus Altererythrobacter (94.8-96.5 %). Strain Y2(T) forms a clade with E. jejuensis CNU001(T) in the cluster of species of the genus Altererythrobacter. Growth of strain Y2(T) was observed at 4-40 °C (optimum, 35-37 °C), at pH 6.0-10.0 (optimum, pH 7.0-8.0) and in the presence of 0-5 % (w/v) NaCl (optimum, 2-3 %). The major cellular fatty acids were found to be C17:1 ?6c (41.5 %), summed feature 8 (C18:1 ?7c and/or C18:1 ?6c; 17.2 %), C17:1 ?8c (11.0 %) and C15:0 2OH (8.1 %). The major respiratory quinone was determine to be ubiquinone 10 (Q-10). The polar lipid analysis indicated the presence of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, one sphingoglycolipid, three unidentified phospholipids, two unidentified glycolipids, two unidentified aminolipids and three unknown lipids. The DNA G + C content of the type strain is 60.0 mol %. On the basis of the data from the polyphasic characterization, strain Y2(T) represents a novel species, for which the name Altererythrobacter oceanensis sp. nov. is proposed. The type strain is Y2(T) (=CGMCC 1.12752(T) =LMG 28109(T)). PMID:25245787

Yang, Yanliu; Zhang, Gaiyun; Sun, Zhilei; Cheung, Man Kit; Huang, Cheney

2014-12-01

262

Gene cloning, sequence analysis, and expression profiles of a novel ?-ring carotenoid hydroxylase gene from the photoheterotrophic green alga Chlorella kessleri.  

PubMed

In this study, a full-length complementary DNA (cDNA) sequence of ?-ring carotenoid hydroxylase (CHY), designated Ckecyp97a1, was isolated via reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends (RACE) methods. The cloned Ckecyp97a1 cDNA was 2,264-bp in length, and contained an open reading frame (ORF) of 1,944-bp with 5'-terminal untranslated region (UTR) of 66-bp and 3'-terminal UTR of 254-bp and encoded a ?-ring CHY protein of 647 amino acids. The deduced protein had a calculated molecular mass of 71.43 kDa with an estimated isoelectric point (pI) of 6.72. Multiple sequence alignment and phylogenetic analysis revealed that Ckecyp97a1 was homologs to known chloroplastic cytochrome P450 (P450) CHY. The typical catalytic motifs of the P450 were highly conserved in the protein sequences of CkeCYP97A1. The Ckecyp97a1 transcriptional expression and carotenoids accumulation were observed under high light (HL) of different wavelengths (white: 390-770 nm and blue: 420-500 nm). The results revealed that Ckecyp97a1 transcript increased strongly throughout the course of the HL illumination treatment (22-70 h) under white HL treatment, while decreased during 10-58 h under blue HL treatment. The concentrations of lutein, ?-carotene, and ?-carotene were relatively steady and below the control level under both treatments. The zeaxanthin concentration was higher under white HL treatment than those under control and blue HL treatments. Ckecyp97a1 gene showed different expression patterns under different light wavelengths treatments. The data obtained in this study demonstrates that CkeCYP97A1 is the enzyme responsible for carotenoid hydroxylation involved in HL acclimation for photoheterotrophic green alga Chlorella kessleri CGMCC 4917. PMID:25260905

Yu, Xiaona; Cui, Hongli; Cui, Yulin; Wang, Yan; Li, Xueqin; Liu, Zhaopu; Qin, Song

2014-11-01

263

Enterobacter xiangfangensis sp. nov., isolated from Chinese traditional sourdough, and reclassification of Enterobacter sacchari Zhu et al. 2013 as Kosakonia sacchari comb. nov.  

PubMed

A Gram-stain-negative bacterial strain, 10-17(T), was isolated from traditional sourdough in Heilongjiang Province, China. The bacterium was characterized by a polyphasic approach, including 16S rRNA gene sequence analysis, RNA polymerase ? subunit (rpoB) gene sequence analysis, DNA gyrase (gyrB) gene sequence analysis, initiation translation factor 2 (infB) gene sequence analysis, ATP synthase ? subunit (atpD) gene sequence analysis, fatty acid methyl ester analysis, determination of DNA G+C content, DNA-DNA hybridization and an analysis of phenotypic features. Strain 10-17(T) was phylogenetically related to Enterobacter hormaechei CIP 103441(T), Enterobacter cancerogenus LMG 2693(T), Enterobacter asburiae JCM 6051(T), Enterobacter mori LMG 25706(T), Enterobacter ludwigii EN-119(T) and Leclercia adecarboxylata LMG 2803(T), having 99.5%, 99.3%, 98.7%, 98.5%, 98.4% and 98.4% 16S rRNA gene sequence similarity, respectively. On the basis of polyphasic characterization data obtained in the present study, a novel species, Enterobacter xiangfangensis sp. nov., is proposed and the type strain is 10-17(T) (?=?LMG 27195(T)?=?NCIMB 14836(T)?=?CCUG 62994(T)). Enterobacter sacchari Zhu et al. 2013 was reclassified as Kosakonia sacchari comb. nov. on the basis of 16S rRNA, rpoB, gyrB, infB and atpD gene sequence analysis and the type strain is strain SP1(T)(?=?CGMCC 1.12102(T)?=?LMG 26783(T)). PMID:24824638

Gu, Chun Tao; Li, Chun Yan; Yang, Li Jie; Huo, Gui Cheng

2014-08-01

264

Comparison of four phaC genes from Haloferax mediterranei and their function in different PHBV copolymer biosyntheses in Haloarcula hispanica  

PubMed Central

Background The halophilic archaeon Haloferax mediterranei is able to accumulate large amounts of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with high molar fraction of 3-hydroxyvalerate (3HV) from unrelated carbon sources. A Polyhydroxyalkanoate (PHA) synthase composed of two subunits, PhaCHme and PhaEHme, has been identified in this strain, and shown to account for the PHBV biosynthesis. Results With the aid of the genome sequence of Hfx. mediterranei CGMCC 1.2087, three additional phaC genes (designated phaC1, phaC2, and phaC3) were identified, which encoded putative PhaCs. Like PhaCHme (54.8 kDa), PhaC1 (49.7 kDa) and PhaC3 (62.5 kDa) possessed the conserved motifs of type III PHA synthase, which was not observed in PhaC2 (40.4 kDa). Furthermore, the longer C terminus found in the other three PhaCs was also absent in PhaC2. Reverse transcription PCR (RT-PCR) revealed that, among the four genes, only phaCHme was transcribed under PHA-accumulating conditions in the wild-type strain. However, heterologous coexpression of phaEHme with each phaC gene in Haloarcula hispanica PHB-1 showed that all PhaCs, except PhaC2, could lead to PHBV accumulation with various 3HV fractions. The three kinds of copolymers were characterized using gel-permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Their thermal properties changed with the variations in monomer composition as well as the different molecular weights (Mw), thus might meet various application requirements. Conclusion We discover three cryptic phaC genes in Hfx. mediterranei, and demonstrate that genetic engineering of these newly identified phaC genes has biotechnological potential for PHBV production with tailor-made material properties. PMID:20727166

2010-01-01

265

Paenibacillus nicotianae sp. nov., isolated from a tobacco sample.  

PubMed

A Gram-stain positive, facultative anaerobic endospore-forming bacterium, designated strain YIM h-19(T), was isolated from a tobacco sample. Cells were observed to be motile rods by means of peritrichous flagella and colonies were observed to be convex, yellow, circular and showed catalase-positive and oxidase-negative reactions. Strain YIM h-19(T) was able to grow at 4-45 °C, pH 6.0-8.0 and 0-3 % NaCl (w/v). The predominant respiratory quinone was identified as MK-7. Major fatty acids were identified as anteiso-C15:0, anteiso-C17:0 and C16:0. The polar lipids were found to be phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and two unidentified polar lipids. The genomic DNA G+C content was determined to be 54 mol%. 16S rRNA gene sequence analysis showed the strain YIM h-19(T) was most closely related to Paenibacillus hordei RH-N24(T) and Paenibacillus hunanensis FeL05(T) with similarities of 98.30 and 94.64 % respectively. However, DNA-DNA hybridization data indicated that the isolate represented a novel genomic species with the genus Paenibacillus. All data from genotypic and phenotypic analyses support the conclusion that strain YIM h-19(T) represents a novel species of the genus Paenibacillus, for which the name Paenibacillus nicotianae sp. nov. is proposed. The type strain is YIM h-19(T) (=CGMCC1.12819(T) = NRRL B-59112(T)). PMID:25239270

Li, Qing-Qing; Zhou, Xing-Kui; Dang, Li-Zhi; Cheng, Juan; Hozzein, Wael N; Liu, Min-Jiao; Hu, Qun; Li, Wen-Jun; Duan, Yan-Qing

2014-12-01

266

Paenibacillus typhae sp. nov., isolated from roots of Typha angustifolia L.  

PubMed

A Gram-stain-positive, facultatively anaerobic and rod-shaped bacterium, designated strain xj7(T), was isolated from roots of Typha angustifolia L. growing in Beijing Cuihu Wetland, China. The isolate was identified as a member of the genus Paenibacillus based on phenotypic characteristics and phylogenetic inference. The novel strain was spore-forming, motile, catalase-positive and oxidase-negative. Optimal growth of strain xj7(T) occurred at 28-30 °C and pH 7.0-7.5. Diphosphatidylglycerol was the most abundant polar lipid and occurred along with phosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid and three unknown aminophospholipids. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The predominant isoprenoid quinone was MK-7. The major fatty acid components were anteiso-C15?:?0 (56.1?%), iso-C16?:?0 (9.1?%), C16?:?0 (8.0?%), iso-C14?:?0 (6.3?%) and iso-C15?:?0 (5.1?%). The G+C content of genomic DNA was 47.9 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain xj7(T) fell within the evolutionary radiation encompassed by the genus Paenibacillus, its closest neighbours were Paenibacillus borealis KK19(T) (97.5?%) and Paenibacillus durus DSM 1735(T) (97.1?%). However, the DNA-DNA relatedness values between strain xj7(T) and P. borealis KK19(T) and between strain xj7(T) and P. durus DSM 1735(T), were both 35?%. Based on phenotypic, chemotaxonomic and phylogenetic properties, strain xj7(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus typhae sp. nov. is proposed. The type strain is xj7(T) (?=?CGMCC 1.11012(T)?=?DSM 25190(T)). PMID:22707528

Kong, Bi He; Liu, Qun Fang; Liu, Min; Liu, Yang; Liu, Lei; Li, Chun Li; Yu, Rong; Li, Yan Hong

2013-03-01

267

Salinibacillus xinjiangensis sp. nov., a halophilic bacterium from a hypersaline lake.  

PubMed

A Gram-positive, endospore-forming, rod-shaped bacterium, designated isolate J4(T), was isolated from a neutral saline lake sample from Xinjiang Uyghur Autonomous Region, China, and subjected to a polyphasic taxonomic investigation. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain J4(T) is most closely related to Salinibacillus aidingensis 25-7(T) (with 96.7?% similarity), Salinibacillus kushneri 8-2(T) (96.5?%), Ornithinibacillus scapharcae TW25(T) (96.4?%), Salirhabdus euzebyi CVS-14(T) (96.4?%) and Ornithinibacillus californiensis MB-9(T) (96.2?%). Chemotaxonomic analysis showed menaquinone-7 (MK-7) to be the major isoprenoid quinone of strain J4(T); diphosphatidylglycerol and phosphatidylglycerol were the major cellular polar lipids and the cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid. The major cellular fatty acids were iso-C15?:?0 and anteiso-C15?:?0. The genomic DNA G+C content of strain J4(T) was determined to be 36.2 mol%. Strain J4(T) was positive for catalase activity and negative for oxidase activity. Strain J4(T) was observed to grow at 25-50 °C (optimal 35-42 °C), pH 6.5-8.0 (optimal 7.0-7.5) and in media containing 1-21?% (w/v) NaCl (optimal 9-12?%). Based on these data, strain J4(T) represents a novel species of the genus Salinibacillus and the name Salinibacillus xinjiangensis sp. nov. is proposed. The type strain is J4(T) (?=?CGMCC 1.12331(T)?=?JCM 18732(T)). PMID:24002474

Yang, Na; Ren, Biao; Liu, Zhi-Heng; Dai, Huan-Qin; Wang, Jian; Zhou, Yu-Guang; Song, Fu-Hang; Zhang, Li-Xin

2014-01-01

268

Syntrophomonas cellicola sp. nov., a spore-forming syntrophic bacterium isolated from a distilled-spirit-fermenting cellar, and assignment of Syntrophospora bryantii to Syntrophomonas bryantii comb. nov.  

PubMed

A spore-forming, anaerobic, syntrophic fatty-acid-oxidizing bacterium, strain 19J-3(T), was isolated from a distilled-spirit-fermenting cellar in Hebei Province, China. The cells were slightly curved rods with a spore at the end of the cell. The optimal temperature for growth was around 37 degrees C and growth occurred in the range 25-45 degrees C. The pH range for growth was 6.5-8.5 and the optimum pH was 7.0-7.5. Crotonate was the only substrate that allowed the strain to grow in pure culture. However, the strain could oxidize saturated fatty acids with four to nine carbon atoms syntrophically in co-culture with Methanobacterium formicicum DSM 1535(T). The strain was not able to utilize sulfate, sulfite, thiosulfate, DMSO, nitrate, fumarate or Fe(III) as electron acceptor. The DNA base composition was 48.8 mol% G+C. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain 19J-3(T) was related to members of the family Syntrophomonadaceae and most closely to Syntrophospora bryantii DSM 3014(T) (94.3 % similarity) and Syntrophomonas wolfei subsp. wolfei DSM 2245(T) (93.6 % similarity). Considering the phylogenetic relationship and phenotypic features, strain 19J-3(T) (=CGMCC 1.5041(T)=JCM 13582(T)) is designated as the type strain of a novel species of the genus Syntrophomonas, Syntrophomonas cellicola sp. nov. Based on the close phylogenetic relationship between the genera Syntrophospora and Syntrophomonas, the presence of sporulation-specific genes in the genome of Syntrophomonas wolfei subsp. wolfei DSM 2245(T) and the description of a spore-forming member of Syntrophomonas, 'Syntrophomonas erecta subsp. sporosyntropha', we propose the assignment of Syntrophospora bryantii to the genus Syntrophomonas as Syntrophomonas bryantii comb. nov. PMID:17012556

Wu, Chenggang; Liu, Xiaoli; Dong, Xiuzhu

2006-10-01

269

Gordonia jinhuaensis sp. nov., a novel actinobacterium, isolated from a VBNC (viable but non-culturable) state in pharmaceutical wastewater.  

PubMed

A Gram-stain positive, aerobic, non-motile and rod-shaped actinobacterial strain, designated as ZYR 51(T), was isolated from pharmaceutical wastewater in Jinhua city, Zhejiang province, Eastern China. Isolation was aided by using a resuscitation-promoting factor, suggesting the strain was recovered from a viable but non-culturable state. Strain ZYR 51(T) was characterized by a polyphasic taxonomic approach. Growth was found to occur at 10-45 °C, pH 6.0-10.0 and 0-9 % NaCl (w/v). Based on the 16S rRNA gene sequence, phylogenetic analysis clearly demonstrated that strain ZYR 51(T) belongs to the genus Gordonia and showed low level similarities (below 97 %) with all other members of this genus. The strain was found to possess meso-diaminopimelic acid (meso-DAP), along with MK-9(H2) as the predominant menaquonine. Mycolic acids were found to be present. C16:0 (34.9 %), 10-methyl C18:0 (30.3 %), iso-C18:0(8.2 %), and summed feature 3 (C16:1 ?6c and/or C16:1?7c as define by MIDI; 18.8 %) were identified as the major cellular fatty acids. The polar lipid profile of strain ZYR 51(T) was found to consist of diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides and some unknown lipids. The genomic DNA G+C content of strain ZYR 51(T) was determined to be 67.7 mol%. The combined genotypic and phenotypic data showed that the strain represents a novel species of the genus Gordonia, for which the name Gordonia jinhuaensis sp. nov. is proposed, with the type strain is ZYR 51(T) (=CGMCC 1.12827(T) = NBRL B-59111(T) = NBRC 110001(T)). PMID:24912980

Li, Shan-Hui; Jin, Yi; Cheng, Juan; Park, Dong-Jin; Kim, Chang-Jin; Hozzein, Wael N; Wadaan, Mohammed A M; Shu, Wen-Sheng; Ding, Lin-Xian; Li, Wen-Jun

2014-08-01

270

Pseudoxanthomonas wuyuanensis sp. nov., isolated from saline-alkali soil.  

PubMed

A bacterium, designated XC21-2(T), was isolated from a saline-alkaline soil sample from China. Cells were Gram-stain-negative, rod-shaped and motile and grew optimally at 35-37 °C, pH 6.0-7.0 and in the presence of 0.5% (w/v) NaCl. Growth occurred in the range pH 5.5-9.0 and in the presence of up to 4?% (w/v) NaCl. The major cellular fatty acids were iso-C15?:?0, iso-C16?:?0 and iso-C17?:?1?9c. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an uncharacterized amino-group-containing polar lipid. The major quinone was ubiquinone 8 (Q-8) and the G+C content of the genomic DNA was 66.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain XC21-2(T) formed a tight phylogenetic lineage with Pseudoxanthomonas dokdonensis KCTC 12543(T) within the genus Pseudoxanthomonas and was most closely related to P. dokdonensis KCTC 12543(T) and P. mexicana ATCC 700993(T), with 97.9 and 97.5?% 16S rRNA gene sequence similarity, respectively. On the basis of the unique physiological profile of the isolate and its phylogenetic divergence from known species, strain XC21-2(T) represents a novel species within the genus Pseudoxanthomonas, for which the name Pseudoxanthomonas wuyuanensis sp. nov. is proposed. The type strain is XC21-2(T) (?=?CGMCC 1.10978(T)?=?KCTC 23877(T)). PMID:24215823

Li, Dai; Pang, Huancheng; Sun, Licui; Fan, Jinping; Li, Yuyi; Zhang, Jianli

2014-03-01

271

Altererythrobacter atlanticus sp. nov., isolated from deep-sea sediment.  

PubMed

A Gram-stain-negative, short rod-shaped bacterium, designated 26DY36(T), was isolated from a deep-sea sediment sample collected from the North Atlantic Rise. The isolate required NaCl and grew best with 2?% (w/v) sea salts at a temperature of 30-35 °C and at pH 7.0. It formed yellow colonies, produced carotenoid-like pigments and did not produce bacteriochlorophyll a. Strain 26DY36(T) was positive for hydrolysis of aesculin, gelatin, tyrosine and Tweens 20, 40, 60 and 80, but negative for hydrolysis of casein, DNA and starch. The major respiratory quinone was ubiquinone-10. The major polar lipid profile consisted of sphingoglycolipid, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and two unidentified glycolipids. The principal fatty acids (>5?%) were C18?:?1?7c, C17?:?1?6c, C15?:?0 2-OH and C16?:?0. The genomic DNA G+C content was 59.4 mol%. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain 26DY36(T) should be assigned to the genus Altererythrobacter. 16S rRNA gene sequence similarities between the isolate and the type strains of species of the genus Altererythrobacter were in the range 92.7-96.5?%. On the basis of phenotypic and genotypic data, strain 26DY36(T) represents a novel species of the genus Altererythrobacter, for which the name Altererythrobacter atlanticus sp. nov. (type strain, 26DY36(T)?=?CGMCC 1.12411(T)?=?JCM 18865(T)) is proposed. PMID:24030689

Wu, Yue-Hong; Xu, Lin; Meng, Fan-Xu; Zhang, Dong-Sheng; Wang, Chun-Sheng; Oren, Aharon; Xu, Xue-Wei

2014-01-01

272

Roseivivax pacificus sp. nov., isolated from deep-sea sediment.  

PubMed

A Gram-stain-negative, short-rod-shaped bacterium, designated 22DY03(T), was isolated from a sediment sample collected from the East Pacific Rise. The isolate required NaCl and grew best with 3-7?% (w/v) sea salts at temperature of between 30 and 35 °C at pH 7.0. It formed non-pigmented colonies and produced exopolysaccharide, but did not produce bacteriochlorophyll a. Strain 22DY03(T) was positive for hydrolysis of aesculin and Tween 20 and negative for hydrolysis of casein, DNA, gelatin, starch and Tween 40, 60 and 80. The major respiratory quinone was ubiquinone-10. The polar lipid profile consisted of a mixture of phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, diphosphatidylglycerol, two unidentified phospholipids and four unidentified polar lipids. The major fatty acids were C19?:?0 cyclo ?8c, C18?:?1?7c and 11-methyl C18?:?1?7c. The genomic DNA G+C content was 64.6 mol%. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain 22DY03(T) should be assigned to the genus Roseivivax. The 16S rRNA gene sequence similarities between the isolate and the type strains of species of the genus Roseivivax were in the range of 94.1-95.8?%. On the basis of phenotypic and genotypic data, it is concluded that strain 22DY03(T) represents a novel species of the genus Roseivivax, for which the name Roseivivax pacificus sp. nov. (type strain 22DY03(T)?=?CGMCC 1.12410(T)?=?JCM 18866(T)) is proposed. PMID:23907228

Wu, Yue-Hong; Meng, Fan-Xu; Xu, Lin; Zhang, Xin-Qi; Wang, Chun-Sheng; Oren, Aharon; Wu, Min; Xu, Xue-Wei

2013-12-01

273

[Polyphasic evidence for the transfer of Promicromonospora yunnanensis to Cellulosimicrobium cellulans].  

PubMed

Polyphasic taxonomic investigations of Promicromonospora yunnanensis AS4.1333 deposited in the China General Microbiological Culture Collection Center (CGMCC) indicated that strain AS4.1333 was closely related to Cellulosimicrobium cellulans DSM43879(T), the two organisms shared a 16S rRNA gene similarity of 99.6% which correspond to 5 nt differences at 1423 positions. Corresponding DNA-DNA reassociation value was 89.3%, significantly higher than 70% cut-off point recommended for the delineation of genomic species by Wayne et al. (1987). Results of chemotaxonomic analyses of cell wall (Whole-organism hydrolysates were rich in rhamnose, fucose and galactose; peptidoglycan type A4a), mycolic acids (One dimensional TLC of whole-organism acid methanolysates revealed the absence of a lower spot (Rf value around 0.47) that corresponded to mycolic acids), principal menaquinones (MK-9 (H4)), phospholipid type (PV) and the G + C content of the DNA (73.8 mol%) supported the conclusions of the genotypic analyses. The very similar morphological and physiological characteristics agreed with the high degree of relatedness. On the basis of phylogenetic analyses based on the almost complete 16S rRNA gene sequence, DNA-DNA reassociation values, chemotaxonomic properties, morphological and physiological characteristics, it is concluded that strain AS4.1333 should be removed from the genus Promicromonospora, and strain AS4.1333 and Cellulosimicrobium cellulans should be considered to be a single species. Promicromonospora yunnanensis AS4.1333 was proposed to transfer into Cellulosimicrobium cellulans. The type strain remains DSM43879T. PMID:17037045

Zhang, Jian-li; Liu, Zhi-heng

2006-08-01

274

Lysinibacillus varians sp. nov., an endospore-forming bacterium with a filament-to-rod cell cycle.  

PubMed

Six Gram-stain-positive, motile, filamentous and/or rod-shaped, spherical spore-forming bacteria (strains GY32(T), L31, F01, F03, F06 and F07) showing polybrominated diphenyl ether transformation were investigated to determine their taxonomic status. After spore germination, these organisms could grow more than one hundred microns long as intact single cells and then divide into rod cells and form endospores in 33 h. The cell-wall peptidoglycan of these strains was type A4?, the predominant menaquinone was MK-7 and the major fatty acids were iso-C16?:?0, iso-C15?:?0 and C16?:?1?7C. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were detected in the polar lipid profile. Analysis of the 16S rRNA gene sequences indicated that these strains should be placed in the genus Lysinibacillus and they were most closely related to Lysinibacillus sphaericus DSM 28(T) (99?% 16S rRNA gene sequence similarity). The gyrB sequence similarity and DNA-DNA relatedness between strain GY32(T) and L. sphaericus JCM 2502(T) were 81?% and 52?%, respectively. The G+C content of the genomic DNA of strain GY32(T) was 43.2 mol%. In addition, strain GY32(T) showed differences in nitrate reduction, starch and gelatin hydrolysis, carbon resource utilization and cell morphology. The phylogenetic distance from its closest relative measured by DNA-DNA relatedness and DNA G+C content, and its phenotypic properties demonstrated that strain GY32(T) represents a novel species of the genus Lysinibacillus, for which the name Lysinibacillus varians sp. nov. is proposed. The type strain is GY32(T) (?=?NBRC 109424(T)?=?CGMCC 1.12212(T)?=?CCTCC M 2011307(T)). PMID:25070216

Zhu, Chunjie; Sun, Guoping; Chen, Xingjuan; Guo, Jun; Xu, Meiying

2014-11-01

275

Burkholderia grimmiae sp. nov., isolated from a xerophilous moss (Grimmia montana).  

PubMed

A Gram-staining-negative, rod-shaped, non-spore-forming bacterium, designated strain R27(T), was isolated from the moss Grimmia montana, collected from Beijing Songshan National Nature Reserve, China, and characterized by using a polyphasic taxonomic approach. The predominant fatty acids of strain R27(T) were C18:1?7c (33.6%), C16:0 (16.3%), summed feature 3 (C16:1?7c and/or C16:1?6c; 15.8%) and C17:0 cyclo (8.7%) and its major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, three uncharacterized aminolipids and an unknown phospholipid. Strain R27(T) contained Q-8 as the dominant isoprenoid quinone and the G+C content of its genomic DNA was 64.6 mol%. On the basis of 16S rRNA gene sequence comparison, strain R27(T) showed 99.1% similarity to the closest related type strain, Burkholderia zhejiangensis OP-1(T), and 97.6% similarity to Burkholderia glathei ATCC 29195(T). However, the DNA-DNA relatedness between strain R27(T) and B. zhejiangensis CCTCC AB 2010354(T) and B. glathei ATCC 29195(T) was 10.2 and 14.9%, respectively. Based on 16S rRNA and rpoB gene sequence similarities and phenotypic and chemotaxonomic data, strain R27(T) is considered to represent a novel species of the genus Burkholderia, for which the name Burkholderia grimmiae sp. nov. is proposed. The type strain is R27(T) (=CGMCC 1.11013(T) =DSM 25160(T)). PMID:23087167

Tian, Yang; Kong, Bi He; Liu, Su Lin; Li, Chun Li; Yu, Rong; Liu, Lei; Li, Yan Hong

2013-06-01

276

Streptosporangium subfuscum sp. nov., isolated from the rhizosphere of marigold (Tagetes erecta L.).  

PubMed

A Gram-stain positive, filamentous bacterial strain, designated strain NEAU-TWSJ13(T), was isolated from the rhizosphere of a marigold (Tagetes erecta L.) plant collected in Heilongjiang Province, northeast China, and characterized using a polyphasic approach. The strain was observed to form abundant aerial hyphae differentiated into spherical sporangia. 16S rRNA gene sequence similarity studies showed that strain NEAU-TWSJ13(T) belongs to the genus Streptosporangium, being most closely related to Streptosporangium fragile DSM 43847(T) (98.6 %). Phylogenetic analysis of the 16S rRNA gene sequence indicated that it formed a phyletic line with S. fragile DSM 43847(T), Streptosporangium jomthongense NBRC 110047(T) (98.4 % 16S rRNA gene similarity) and Streptosporangium violaceochromogenes DSM 43849(T) (97.6 % 16S rRNA gene similarity). A combination of DNA-DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-TWSJ13(T) can be distinguished from S. fragile DSM 43847(T) and S. jomthongense NBRC 110047(T). Moreover, strain NEAU-TWSJ13(T) can also be differentiated from S. violaceochromogenes DSM 43849(T) and other Streptosporangium species showing high 16S rRNA gene sequence similarity (>98.0 %) by morphological and physiological characteristics. Therefore, it is proposed that strain NEAU-TWSJ13(T) represents a novel species of the genus Streptosporangium, for which the name Streptosporangium subfuscum sp. nov. is proposed. The type strain is NEAU-TWSJ13(T) ( = CGMCC 4.7146(T) = DSM = 46724(T)). PMID:25256952

Zhou, Ying; Liu, Chongxi; Zhang, Yuejing; Li, Chuang; Xing, Jia; Li, Lianjie; Zhou, Shuyu; Wang, Xiangjing; Xiang, Wensheng

2014-12-01

277

Rhodococcus kronopolitis sp. nov., a novel actinobacterium isolated from a millipede (Kronopolites svenhedind Verhoeff).  

PubMed

A novel actinobacterium, designated strain NEAU-ML12(T), was isolated from a millipede (Kronopolites svenhedind Verhoeff), which was collected from Fenghuang Mountain in Wuchang, Heilongjiang Province, north China. The strain was characterized using a polyphasic approach. Strain NEAU-ML12(T) was found to have morphological and chemotaxonomic characteristics typical of the members of the genus Rhodococcus. 16S rRNA gene sequence similarity analysis showed that the strain NEAU-ML12(T) belongs to the genus Rhodococcus, and was most closely related to Rhodococcus tukisamuensis Mb8(T) (98.9 %) and Rhodococcus koreensis DNP505(T) (97.7 %). Phylogenetic analysis based on 16S rRNA gene sequences also demonstrated that strain NEAU-ML12(T) should be classified in the genus Rhodococcus, forming a distinct clade with R. tukisamuensis Mb8(T) supported by a 99 % bootstrap value. However, the DNA-DNA relatedness between strain NEAU-ML12(T) and R. tukisamuensis Mb8(T) was found to be 41.9 ± 0.7 %. Furthermore, strain NEAU-ML12(T) could also be differentiated from R. tukisamuensis Mb8(T) and other closely related strains (R. koreensis DNP505(T) and Rhodococcus maanshanensis M712(T)) by morphological and physiological characteristics. Therefore, it is proposed that strain NEAU-ML12(T) represents a novel species of the genus Rhodococcus, for which the name Rhodococcus kronopolitis sp. nov. is proposed. The type strain is NEAU-ML12(T) (=CGMCC 4.7145(T) = DSM 46702(T)). PMID:25261081

Liu, Hui; Zhang, Yuejing; Liu, Chongxi; Fang, Baozhu; Li, Chuang; Guan, Xuejiao; Li, Lianjie; Wang, Xiangjing; Xiang, Wensheng

2014-12-01

278

Bacillus mesonae sp. nov., isolated from the root of Mesona chinensis.  

PubMed

A Gram-stain-positive, short rod-shaped and motile, mildly halotolerant, endospore-forming bacterium, FJAT-13985(T), was isolated from the internal tissues of Mesona chinensis root. Strain FJAT-13985(T) grew at 20-45 °C (optimum 30 °C) and pH 5.7-9.0 (optimum pH 7.0) and in the presence of 0-2?% (w/v) NaCl [optimum 1?% (w/v)]. The strain was catalase-positive and oxidase-negative. The cell wall of strain FJAT-13985(T) contained meso-diaminopimelic acid and the predominant isoprenoid quinone was MK-7 (97.4?%). The major fatty acids of the strain were anteiso-C15?:?0 (23.3?%) and iso-C15?:?0 (40.8?%). The DNA G+C content was 41.64 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain FJAT-13985(T) is a member of the genus Bacillus and is most closely related to Bacillus drentensis DSM 15600(T) (98.4?%), Bacillus vireti DSM 15602(T) (98.2?%) and Bacillus novalis DSM 15603(T) (98.3?%). DNA-DNA hybridization indicated that relatedness between strain FJAT-13985(T) and its closest relative, B. drentensis DSM 15600(T), was 36.63?%. The phenotypic, chemotaxonomic and genotypic properties clearly indicate that strain FJAT-13985(T) represents a novel species of the genus Bacillus, for which the name Bacillus mesonae sp. nov. is proposed. The type strain is FJAT-13985(T) (?=?DSM 25968(T)?=?CGMCC1.12238(T)). PMID:25013229

Liu, Bo; Liu, Guo-Hong; Hu, Gui-Hing; Chen, Mei-Chun

2014-10-01

279

Ureibacillus defluvii sp. nov., isolated from a thermophilic microbial fuel cell.  

PubMed

A thermophilic bacterium, designated DX-1T, was isolated from the anode biofilm of a microbial fuel cell (MFC). Cells of strain DX-1T were oxidase-positive, catalase-positive and Gram-staining-negative. The strain was found to be rod-shaped and non-motile and to produce subterminal spores. The strain was able to grow with NaCl at concentrations ranging from 0 to 6?%, at temperatures of 25-60 °C (optimum 55 °C) and pH 6.0-8.0 (optimum pH 7.0). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain DX-1T formed a cluster with Ureibacillus thermosphaericus DSM 10633T (96.9% 16S rRNA sequence similarity), Ureibacillus composti DSM 17951T (95.8%), Ureibacillus thermophilus DSM 17952T (95.7%) and Ureibacillus terrenus DSM 12654T (95.3%). The G+C content of the genomic DNA was 40.4 mol%. The major quinone was MK-7, the peptidoglycan type was L-Lys?D-Asp, and the major cellular fatty acids (>5%) were iso-C16:0 and iso-C14:0. The polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol and phospholipids of unknown composition. Based on phenotypic characteristics, chemotaxonomic features and results of phylogenetic analyses, the strain was determined to represent a distinct novel species of the genus Ureibacillus, and the name proposed for the novel species is Ureibacillus defluvii sp. nov., with type strain DX-1T (=CGMCC 1.12358T=KCTC 33127T). PMID:24491829

Zhou, Shungui; Tang, Jia; Qin, Dongxing; Lu, Qin; Yang, Guiqin

2014-05-01

280

Amphiplicatus metriothermophilus gen. nov., sp. nov., a thermotolerant alphaproteobacterium isolated from a hot spring.  

PubMed

A thermotolerant, Gram-strain-negative, non-spore-forming and strictly aerobic bacterium, designated GU51(T), was isolated from Guhai hot spring in Jimsar county, Xinjiang province, north-west China. Each cell of strain GU51(T) consisted of an oval body and two symmetrical long (3-6 µm) prosthecae. The strain moved by polar flagellum. Oxidase and catalase were produced. Strain GU51(T) grew within the ranges of 37-65 °C (optimum 48-50 °C), 0.5-7.5% (w/v) NaCl (optimum 2-3%) and pH 6.0-9.0 (optimum pH 7.5). The major respiratory quinone detected was ubiquinone 10 (U-10) and the genomic DNA G+C content was 66.7±0.4 mol%. Major fatty acids (>5%) were C(16?:?0), C(18?:?1)?7c and 11-methyl C(18?:?1)?7c. The polar lipids consisted of diphosphatidylglycerol, five glycolipids, phosphatidylglycerol and an unknown phospholipid. Phylogenetic analysis showed the closest relatives of strain GU51(T) were members of the genus Parvularcula with 92.3% 16S rRNA gene sequence similarity. On the basis of this polyphasic taxonomic characterization, it is suggested that strain GU51(T) represents a novel species of a new genus in the family 'Parvularculaceae', for which the name Amphiplicatus metriothermophilus gen. nov., sp. nov. is proposed. The type strain of the type species is GU51(T) (?=?CGMCC 1.12710(T)?=?JCM 19779(T)). PMID:24867176

Zhen-Li, Zhang; Xin-Qi, Zhang; Nan, Wu; Wen-Wu, Zhang; Xu-Fen, Zhu; Yi, Cao; Min, Wu

2014-08-01

281

Sphingomonas gimensis sp. nov., a novel Gram-negative bacterium isolated from abandoned lead-zinc ore mine.  

PubMed

A novel bacterial strain designated 9PNM-6(T) was isolated from an abandoned lead-zinc ore mine site in Meizhou, Guangdong Province, China. The isolate was found to be Gram-negative, rod-shaped, orange-pigmented, strictly aerobic, oxidase- and catalase-positive. Growth occurred at 0-4 % NaCl (w/v, optimum, 0 %), at pH 6.0-8.0 (optimum, pH 7.0) and at 15-32 °C (optimum, 28-30 °C). Phylogenetic analysis based on 16S rRNA gene sequence similarities showed that strain 9PNM-6(T) belongs to the genus Sphingomonas, with the highest sequence similarities with Sphingomonas jejuensis NBRC 107775(T) (99.7 %), Sphingomonas koreensis KCTC 2882(T) (95.1 %) and Sphingomonas dokdonesis KCTC 12541(T) (95.1 %). The chemotaxonomic characteristics of strain 9PNM-6(T) were consistent with those of the genus Sphingomonas. The predominant respiratory quinone was identified as ubiquinone Q-10, the major polyamine as sym-homospermidine, and the major cellular fatty acids as C18:1 ?7c, C16:0, C16:1 ?7c and/or C16:1 ?6c and C14:0 2-OH. The major polar lipids are sphingoglycolipid, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatideylcholine, an unidentified phospholipid and four unidentified aminolipids. The genomic DNA G+C content of strain 9PNM-6(T) was determined to be 69.2 ± 0.6 mol%. Based on comparative analyses of morphological, physiological and chemotaxonomic data, and levels of DNA-DNA relatedness values, strain 9PNM-6(T) is considered to represent a novel species of the genus Sphingomonas, for which the name Sphingomonas gimensis sp. nov. (Type strain 9PNM-6(T) = GIMCC 1.655(T) = CGMCC 1.12671(T) = DSM 27569(T)) is proposed. PMID:24718620

Feng, Guang-Da; Yang, Song-Zhen; Wang, Yong-Hong; Zhao, Guo-Zhen; Deng, Ming-Rong; Zhu, Hong-Hui

2014-06-01

282

Description of a Gram-negative bacterium, Sphingomonas guangdongensis sp. nov.  

PubMed

A Gram-stain-negative bacterial strain, designated 9NM-8T, was isolated from an abandoned lead-zinc ore in Mei county, Meizhou, Guangdong province, PR China. The isolate was orange-pigmented, aerobic, oxidase- and catalase-positive, motile with lophotrichous flagella and rod-shaped. Strain 9NM-8T grew optimally at pH 7.0 and 30 °C and in the absence of NaCl on R2A agar. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 9NM-8T belongs to the genus Sphingomonas, with highest sequence similarities to Sphingomonas azotifigens KACC 14484T (96.1%), Sphingomonas trueperi DSM 7225T (96.0%) and Sphingomonas pituitosa DSM 13101T (95.6?%). Strain 9NM-8T contained Q-10 as the predominant ubiquinone. The major fatty acids included C18:1?7c, C16:0, C16:1?7c and/or C16?:?1?6c (summed feature 3) and 11-methyl C18:1?7c. The DNA G+C content was 69.6±1.3 mol%. The major component in the polyamine pattern was sym-homospermidine and the polar lipid profile contained sphingoglycolipid, phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, an unidentified glycolipid and two unidentified phospholipids. Based on comparative analysis of physiological, chemotaxonomic and phylogenetic characteristics, strain 9NM-8T should be considered to represent a novel species of the genus Sphingomonas, for which the name Sphingomonas guangdongensis sp. nov. is proposed. The type strain is 9NM-8T (=GIMCC 1.653T=CGMCC 1.12672T=DSM 27570T). PMID:24523446

Feng, Guang-Da; Yang, Song-Zhen; Wang, Yong-Hong; Zhang, Xiu-Xiu; Zhao, Guo-Zhen; Deng, Ming-Rong; Zhu, Hong-Hui

2014-05-01

283

Flavobacterium lacus sp. nov., isolated from a high-altitude lake, and emended description of Flavobacterium filum.  

PubMed

Two Gram-stain-negative, non-motile, rod-shaped bacterial strains, designated NP180(T) and NR80, were isolated from water of Nam Co Lake, located in Tibet, China. Growth of strains NP180(T) and NR80 occurred at 4-25 °C and at pH 6.5-10.0 (optima, 15-20 °C and pH 7.5-8.5). The 16S rRNA gene sequence similarity to the phylogenetically closest related strains, Flavobacterium filum EMB 34(T), F. ponti GSW-R14(T) and F. gelidilacus LMG 21477(T), was 95.1, 94.8 and 94.6?%, respectively. The predominant fatty acids were iso-C15?:?0, iso-C15?:?1 G, iso-C17?:?0 3-OH and summed feature 9 (comprising iso-C17?:?1?9c and/or 10-methyl C16?:?0). The major menaquinone of the two strains was menaquinone 6 (MK-6). Phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid were the major polar lipids in both strains. The G+C contents of the genomic DNA were 34.9 and 35.1 mol%, respectively, for strains NP180(T) and NR80. DNA-DNA relatedness between strains NP180(T) and NR80 was 99?%, indicating that they belong to the same species. According to phylogenetic inference and phenotypic characteristics, a novel species, Flavobacterium lacus sp. nov., is proposed. The type strain is NP180(T) (?=?CGMCC 1.12504(T)?=?NBRC 109715(T)). An emended description of Flavobacterium filum is also provided. PMID:24425814

Li, Aihua; Liu, Hongcan; Sun, Bingda; Zhou, Yuguang; Xin, Yuhua

2014-03-01

284

Wenyingzhuangia marina gen. nov., sp. nov., a member of the family Flavobacteriaceae isolated from a recirculating mariculture system.  

PubMed

A Gram-stain-negative, strictly aerobic and heterotrophic bacterial strain, designed strain D1(T), was isolated from a recirculating mariculture system in Tianjin, China. Its taxonomic position was determined using a polyphasic approach. Cells of strain D1(T) were non-flagellated short rods, 0.3-0.5 µm wide and 0.5-1.0 µm long. Growth was observed at 15-30 °C (optimum, 25 °C), at pH 5.5-9.0 (optimum, pH 6.5-7.0) and in the presence of 1-8% (w/v) NaCl (optimum, 2-3 %). Cells contained carotenoid pigments but not flexirubin-type pigments. Strain D1(T) contained MK-6 as the sole menaquinone and phosphatidylethanolamine (PE) as the sole phospholipid and four unidentified lipids. The major cellular fatty acids (>10%) were iso-C15 : 0 (23.2 %), iso-C17 : 0 3-OH (15.2%), C(16 : 1)?7c/C(16 : 1)?6c (14.3%), iso-C(15 : 0) 3-OH (13.5%) and iso-C15 : 1 G (10.8%). 16S rRNA gene sequence analyses indicated that strain D1(T) belonged to the family Flavobacteriaceae and showed closest phylogenetic relationship to the genus Lutibacter, with highest sequence similarity to Lutibacter aestuarii MA-My1(T) (92.2%). The DNA G+C content of strain D1(T) was 35.9 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain D1(T) was considered to represent a novel species in a new genus of the family Flavobacteriaceae, for which the name Wenyingzhuangia marina gen. nov., sp. nov. is proposed. The type strain of the type species is D1(T) (?=?CGMCC 1.12162(T)?=?JCM 18494(T)). PMID:24096358

Liu, Ying; Liu, Liang-Zi; Liu, Hong-Can; Zhou, Yu-Guang; Qi, Fang-Jun; Liu, Zhi-Pei

2014-02-01

285

Roseicitreum antarcticum gen. nov., sp. nov., an aerobic bacteriochlorophyll a-containing alphaproteobacterium isolated from Antarctic sandy intertidal sediment.  

PubMed

A novel Gram-negative, non-motile bacterium, designated strain ZS2-28(T), was isolated from sandy intertidal sediment samples collected from the coastal regions of the Chinese Antarctic Zhongshan Station on the Larsemann Hills, Princess Elizabeth Land, East Antarctica. Strain ZS2-28(T) was obligately heterotrophic, strictly aerobic, psychrotolerant (growth occurred at 0-33 °C) and moderately halophilic (optimal growth in 7-8?% NaCl). A single major peak at 872-874 nm in the infrared absorption spectrum indicated the presence of bacteriochlorophyll a. Poly-?-hydroxybutyrate accumulation and slime production were also detected. The predominant cellular fatty acid was C??:??7c, with C??:? 3-OH, C??:?, C??:? cyclo, C??:??8c cyclo and summed feature 3 (C??:??7c and/or iso-C??:? 2-OH) present in smaller amounts. The respiratory quinone was Q-10. The main polar lipids were phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified aminolipid. The G+C content of the genomic DNA was 63.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZS2-28(T) formed a distinct evolutionary lineage within the clade containing members of the genera Roseibaca, Roseinatronobacter and Rhodobaca of the class Alphaproteobacteria. On the basis of its phylogenetic position, as well as its phenotypic and chemotaxonomic characteristics, strain ZS2-28(T) represents a novel species of a novel genus, for which the name Roseicitreum antarcticum gen. nov., sp. nov. is proposed. The type strain is ZS2-28(T) (?=?CGMCC 1.8894(T) ?=?LMG 24863(T)). PMID:20889763

Yu, Yong; Yan, Shu-Lin; Li, Hui-Rong; Zhang, Xiao-Hua

2011-09-01

286

Geobacter anodireducens sp. nov., an exoelectrogenic microbe in bioelectrochemical systems.  

PubMed

A previously isolated exoelectrogenic bacterium, strain SD-1(T), was further characterized and identified as a representative of a novel species of the genus Geobacter. Strain SD-1(T) was Gram-negative, aerotolerant, anaerobic, non-spore-forming, non-fermentative and non-motile. Cells were short, curved rods (0.8-1.3 µm long and 0.3 µm in diameter). Growth of strain SD-1(T) was observed at 15-42 °C and pH 6.0-8.5, with optimal growth at 30-35 °C and pH 7. Analysis of 16S rRNA gene sequences indicated that the isolate was a member of the genus Geobacter, with the closest known relative being Geobacter sulfurreducens PCA(T) (98?% similarity). Similar to other members of the genus Geobacter, strain SD-1(T) used soluble or insoluble Fe(III) as the sole electron acceptor coupled with the oxidation of acetate. However, SD-1(T) could not reduce fumarate as an electron acceptor with acetate oxidization, which is an important physiological trait for G. sulfurreducens. Moreover, SD-1(T) could grow in media containing as much as 3?% NaCl, while G. sulfurreducens PCA(T) can tolerate just half this concentration, and this difference in salt tolerance was even more obvious when cultivated in bioelectrochemical systems. DNA-DNA hybridization analysis of strain SD-1(T) and its closest relative, G. sulfurreducens ATCC 51573(T), showed a relatedness of 61.6?%. The DNA G+C content of strain SD-1(T) was 58.9 mol%. Thus, on the basis of these characteristics, strain SD-1(T) was not assigned to G. sulfurreducens, and was instead classified in the genus Geobacter as a representative of a novel species. The name Geobacter anodireducens sp. nov. is proposed, with the type strain SD-1(T) (?=?CGMCC 1.12536(T)?=?KCTC 4672(T)). PMID:25052395

Sun, Dan; Wang, Aijie; Cheng, Shaoan; Yates, Matthew; Logan, Bruce E

2014-10-01

287

Cellulosilyticum ruminicola gen. nov., sp. nov., isolated from the rumen of yak, and reclassification of Clostridium lentocellum as Cellulosilyticum lentocellum comb. nov.  

PubMed

An obligate anaerobic, Gram-staining-negative, mesophilic, cellulolytic bacterium, strain H1(T), was isolated from the rumen content of yak. Cells were straight to slightly curved rods, 0.8-1.0 x 3.0-4.0 microm in size, non-motile and encapsulated with mucous materials. Elliptical and terminal spores that swelled the cells were produced occasionally. The strain grew at 25-45 degrees C (optimum, 38 degrees C) and pH 6.0-7.8 (optimum, pH 6.7). Cellulose, cellobiose, xylan, xylose and maltose were used as carbon and energy sources, but not glucose. Products from cellulose and cellobiose fermentation were formic acid, acetic acid, carbon dioxide and trace amounts of ethanol, lactic acid and succinic acid. The genomic DNA G+C content was 33.7+/-1.2 mol%. The predominant fatty acids were C(16 : 0) (27.1 %), C(14 : 0) (9.2 %) and iso-C( 16 : 0) (6.4%). Based on the 16S rRNA gene sequence analysis, strain H1(T) was affiliated to the clostridial rRNA cluster XIVb and showed the highest 16S rRNA gene sequence similarity to Clostridium lentocellum DSM 5427(T) (96.0 %). These two strains formed a distinct lineage of the family 'Lachnospiraceae '. Based on data from this polyphasic taxonomic study, a new genus, Cellulosilyticum gen. nov., is proposed. Cellulosilyticum ruminicola sp. nov. is proposed for strain H1(T). The type strain of Cellulosilyticum ruminicola sp. nov. is strain H1(T) (=CGMCC 1.5065(T)=JCM 14822(T)). Clostridium lentocellum was reclassified in the new genus as Cellulosilyticum lentocellum comb. nov. (type strain RHM5(T)=ATCC 49066( T)=DSM 5427(T)=NCIMB 11756(T)). PMID:19661493

Cai, Shichun; Dong, Xiuzhu

2010-04-01

288

Lactococcus fujiensis sp. nov., a lactic acid bacterium isolated from vegetable matter.  

PubMed

Three strains of lactic acid bacteria, designated NJ 317(T), NJ 414 and NJ 415, were isolated from the outer leaves of Chinese cabbages (Brassica rapa L. var. glabra Regel) and characterized taxonomically. The strains were gram-reaction-positive, catalase-negative, facultatively anaerobic cocci that did not produce gas from glucose and formed L-lactic acid. The major fatty acids were C(18?:?1)?9c, C(16?:?0), C(14?:?0) and summed feature 10. Morphological, physiological and phylogenetic data indicated that the strains belonged to the genus Lactococcus. These strains shared similar phenotypic characteristics and exhibited DNA relatedness values >96.6?% to each other, indicating that they represent a single species. The DNA G+C contents of the three strains were 42.1-42.5 mol%. 16S rRNA gene sequences of the novel strains were determined and aligned with those of other species of the genus Lactococcus. On the basis of phylogenetic analysis the three strains grouped with other members of the genus Lactococcus. Lactococcus lactis and Lactococcus garvieae were the most closely related species, sharing a sequence similarity value of 94.4?% with the three strains. Ribotyping patterns, however, revealed that these strains were well-separated from reference strains of species of the genus Lactococcus and DNA-DNA hybridization studies indicated that the novel strains had low levels (<20.2?%) of DNA relatedness with reference strains of L. lactis, L. garvieae and other type strains of previously described species, showing that they represent a different species. Based on this evidence, strains NJ 317(T), NJ 414 and NJ 415 represent a novel species of the genus Lactococcus, for which the name Lactococcus fujiensis sp. nov. is proposed. The type strain is NJ 317(T) (?=?JCM16395(T) ?=?CGMCC 1.10453(T)). PMID:20675438

Cai, Yimin; Yang, Jinsong; Pang, Huili; Kitahara, Maki

2011-07-01

289

Terrimicrobium sacchariphilum gen. nov., sp. nov., an anaerobic bacterium of the class 'Spartobacteria' in the phylum Verrucomicrobia, isolated from a rice paddy field.  

PubMed

A strictly anaerobic, mesophilic, carbohydrate-fermenting bacterium, designated NM-5T, was isolated from a rice paddy field. Cells of strain NM-5(T) were Gram-stain-negative, non-motile, non-spore-forming, short rods (0.5-0.7 µm×0.6-1.2 µm). The strain grew optimally at 37 °C (growth range 20-40 °C) and pH 7.0 (pH 5.5-8.0). The strain could grow fermentatively on arabinose, xylose, fructose, galactose, glucose, ribose, mannose, cellobiose, lactose, maltose and sucrose. The main end-products of glucose fermentation were acetate and propionate. Organic acids, alcohols and amino acids were not utilized for growth. Yeast extract was not required but stimulated the growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite, and Fe (III) nitrilotriacetate were not used as terminal electron acceptors. The DNA G+C content was 46.3 mol%. The major cellular fatty acids were iso-C14:0, C18:0 and C16:0. 16S rRNA gene sequence analysis revealed that strain NM-5T belongs to the class 'Spartobacteria', subdivision 2 of the bacterial phylum Verrucomicrobia. Phylogenetically, the closest species was 'Chthoniobacter flavus' (89.6% similarity in 16S rRNA gene sequence). A novel genus and species, Terrimicrobium sacchariphilum gen. nov., sp. nov., is proposed. The type strain of the type species is NM-5T (=JCM 17479T=CGMCC 1.5168T). PMID:24535138

Qiu, Yan-Ling; Kuang, Xiao-zhu; Shi, Xiao-shuang; Yuan, Xian-zheng; Guo, Rong-bo

2014-05-01

290

Oligosphaera ethanolica gen. nov., sp. nov., an anaerobic, carbohydrate-fermenting bacterium isolated from methanogenic sludge, and description of Oligosphaeria classis nov. in the phylum Lentisphaerae.  

PubMed

A mesophilic, obligately anaerobic, carbohydrate-fermenting bacterium, designated 8KG-4(T), was isolated from an upflow anaerobic sludge blanket reactor treating high-strength organic wastewater from salted vegetable production processes. Cells of strain 8KG-4(T) were non-motile, spherical and 0.7-1.5 µm in diameter (mean, 1.0 µm). Spore formation was not observed under any culture conditions tested. The strain grew optimally at 37 °C (range for growth 25-40 °C) and pH 7.0 (range, pH 6.5-7.5), and could grow fermentatively on glucose, ribose, xylose, galactose and sucrose. The main end products of glucose fermentation were acetate, ethanol and hydrogen. Organic acids, alcohols and amino acids were not utilized for growth. Yeast extract was not required for growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite and Fe(III) nitrilotriacetate were not used as terminal electron acceptors. The G+C content of the genomic DNA was 61.1 mol%. 16S rRNA gene sequence analysis revealed that the isolate represented a previously uncultured lineage at the subphylum level within the phylum Lentisphaerae known as 'WWE2 subgroup I'. The major cellular fatty acids were anteiso-C(15?:?0), iso-C(16?:?0), C(16?:?0) and anteiso-C(17?:?0). Respiratory quinones were not detected. The most abundant polar lipid of strain 8KG-4(T) was phosphatidylethanolamine. A novel genus and species, Oligosphaera ethanolica gen. nov., sp. nov., is proposed to accommodate strain 8KG-4(T) (?=?JCM 17152(T)?=?DSM 24202(T) ?=?CGMCC 1.5160(T)). In addition, we formally propose Oligosphaeria classis nov. and the subordinate taxa Oligosphaerales order nov. and Oligosphaeraceae fam. nov. PMID:22523166

Qiu, Yan-Ling; Muramatsu, Mizuho; Hanada, Satoshi; Kamagata, Yoichi; Guo, Rong-Bo; Sekiguchi, Yuji

2013-02-01

291

Hydrogenispora ethanolica gen. nov., sp. nov., an anaerobic carbohydrate-fermenting bacterium from anaerobic sludge.  

PubMed

An anaerobic, spore-forming, ethanol-hydrogen-coproducing bacterium, designated LX-BT, was isolated from an anaerobic sludge treating herbicide wastewater. Cells of strain LX-BT were non-motile rods (0.3-0.5×3.0-18.0 µm). Spores were terminal with a bulged sporangium. Growth occurred at 20-50 °C (optimum 37-45 °C), pH 5.0-8.0 (optimum pH 6.0-7.7) and 0-2.5% (w/v) NaCl. The strain could grow fermentatively on glucose, maltose, arabinose, fructose, xylose, ribose, galactose, mannose, raffinose, sucrose, pectin, starch, glycerol, fumarate, tryptone and yeast extract. The major end-products of glucose fermentation were acetate, ethanol and hydrogen. Yeast extract was not required but stimulated growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite, anthraquinone-2,6-disulfonate, fumarate and Fe (III) nitrilotriacetate were not used as terminal electron acceptors. The G+C content of the genomic DNA was 56.1 mol%. The major cellular fatty acids were anteiso-C15:0, iso-C14:0 and C16:0. The most abundant polar lipids of strain LX-BT were diphosphatidylglycerol and phosphatidylglycerol. 16S rRNA gene sequence analysis revealed that it belongs to an as-yet-unidentified taxon at the order- or class-level (OPB54) within the phylum Firmicutes, showing 86.5% sequence similarity to previously described species of the Desulfotomaculum cluster. The name Hydrogenispora ethanolica gen. nov., sp. nov. is proposed to accommodate strain LX-BT (=DSM 25471T=JCM 18117T=CGMCC 1.5175T) as the type strain. PMID:24554637

Liu, Yi; Qiao, Jiang-Tao; Yuan, Xian-Zheng; Guo, Rong-Bo; Qiu, Yan-Ling

2014-05-01

292

Pleomorphobacterium xiamenense gen. nov., sp. nov., a moderate thermophile isolated from a terrestrial hot spring.  

PubMed

An aerobic, motile, moderately thermophilic rod, designated strain CLW(T), was isolated from a terrestrial hot spring in an exposition garden in Xiamen City, Fujian Province, the People's Republic of China. Strain CLW(T) formed beige, dry colonies on solid 2216E medium and flocks in liquid medium. Cells were Gram-stain-negative, short rods (1.0-3.0 µm long and 0.4-0.6 µm wide) with six or more polar flagella. The temperature and pH for growth of strain CLW(T) were 28-65 °C (optimum, 50-58 °C) and pH 5.5-9.5 (optimum, pH 6.0-8.0). Growth occurred in the presence of 0.3-6.0?% NaCl (optimum 2.5-4.5?%). Phylogenetic analysis based on 16S rRNA gene sequences showed that the closest relative of the isolate was Amaricoccus kaplicensis Ben 101(T) (94.3?% sequence similarity). The DNA G+C content of strain CLW(T) was 72.2 mol%. The respiratory quinone was ubiquinone 10. The predominant polar lipids consisted of phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids (>10?%) were summed feature 8 (consisting of C18?:?1?7c and/or C18?:?1?6c), C18?:?1?7c 11-methyl and C18?:?0. Based on phylogenetic, physiological and biochemical data and DNA G+C content, strain CLW(T) is considered to represent a novel species of a new genus in the family Rhodobacteraceae, for which the name Pleomorphobacterium xiamenense gen. nov., sp. nov. is proposed. The type strain of the type species is CLW(T) (?=?LMG 26245(T)?=?CGMCC 1.10808(T)?=?MCCC 1A06272(T)). PMID:23041633

Yin, Decui; Chen, Liwei; Ao, Jingqun; Ai, Chunxiang; Chen, Xinhua

2013-05-01

293

Clostridium algifaecis sp. nov., an anaerobic bacterial species from decomposing algal scum.  

PubMed

Two anaerobic bacterial strains, MB9-7(T) and MB9-9, were isolated from decomposing algal scum and were characterized using a polyphasic approach. Phylogenetic analysis of 16S rRNA gene sequences showed that strains MB9-7(T) and MB9-9 are closely related to each other (99.7?% similarity) and they are also closely related to Clostridium tyrobutyricum (96.5?%). The two strains were Gram-stain positive and rod-shaped. Growth occurred at 20-45 °C, at pH 4.0-8.0 and at NaCl concentrations of up to 2?% (w/v). Acid was produced from glucose, xylose and mannose. Products of fermentation in PYG medium were mainly butyrate, acetate, carbon dioxide and hydrogen. The predominant cellular fatty acids were C14?:?0 and C16?:?0. The cellular polar lipids comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, two glycolipids, one phospholipid, one aminophospholipid and two aminolipids. The DNA G+C contents of strain MB9-7(T) and MB9-9 were 27.9 and 28.7 mol%, respectively. These results support the assignment of the new isolates to the genus Clostridium and also distinguish them from other species of the genus Clostridium. Hence, it is proposed that strains MB9-7(T) and MB9-9 represent a novel species of the genus Clostridium, with the suggested name Clostridium algifaecis sp. nov. The type strain is MB9-7(T) (?=?CGMCC 1.5188(T)?=?DSM 28783(T)). PMID:25168611

Wu, Yu-Fan; Zheng, Hui; Wu, Qing-Long; Yang, Hong; Liu, Shuang-Jiang

2014-11-01

294

Altererythrobacter xiamenensis sp. nov., an algicidal bacterium isolated from red tide seawater.  

PubMed

A Gram-stain-negative, yellow-pigmented, aerobic bacterial strain, designated LY02(T), was isolated from red tide seawater in Xiamen, Fujian Province, China. Growth was observed at temperatures from 4 to 44 °C, at salinities from 0 to 9% and at pH from 6 to 10. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that the isolate was a member of the genus Altererythrobacter, which belongs to the family Erythrobacteraceae. Strain LY02(T) was related most closely to Altererythrobacter marensis MSW-14(T) (97.2% 16S rRNA gene sequence similarity), followed by Altererythrobacter ishigakiensis JPCCMB0017(T) (97.1%), Altererythrobacter epoxidivorans JCS350(T) (97.1%) and Altererythrobacter luteolus SW-109(T) (97.0%). The dominant fatty acids were C(18 : 1)?7c, C(17 : 1)?6c and summed feature 3 (comprising C(16 : 1)?7c and/or C(16 : 1)?6c). DNA-DNA hybridization showed that strain LY02(T) possessed low DNA-DNA relatedness to A. marensis MSW-14(T), A. ishigakiensis JPCCMB0017(T), A. epoxidivorans JCS350(T) and A. luteolus SW-109(T) (mean ± SD of 33.2 ± 1.3, 32.1 ± 1.0, 26.7 ± 0.7 and 25.2 ± 1.1?%, respectively). The G+C content of the chromosomal DNA was 61.2 mol%. The predominant respiratory quinone was ubiquinone-10 (Q-10). According to its morphology, physiology, fatty acid composition and 16S rRNA gene sequence data, the novel strain most appropriately belongs to the genus Altererythrobacter, but can readily be distinguished from recognized species. The name Altererythrobacter xiamenensis sp. nov. is proposed (type strain LY02(T)?=?CGMCC 1.12494(T)?=?KCTC 32398(T)?=?NBRC 109638(T)). PMID:24158949

Lei, Xueqian; Li, Yi; Chen, Zhangran; Zheng, Wei; Lai, Qiliang; Zhang, Huajun; Guan, Chengwei; Cai, Guanjing; Yang, Xujun; Tian, Yun; Zheng, Tianling

2014-02-01

295

Undibacterium terreum sp. nov., isolated from permafrost soil.  

PubMed

The bacterial strain C3(T) was isolated from permafrost soil in Beijicun, Mohe County, Heilongjiang province, China. Cells of strain C3(T) were Gram-stain-negative rods, 0.3-0.4 µm in diameter and 1.0-2.6 µm in length. Strain C3(T) was strictly aerobic. Growth occurred at 15-37 °C but not at 4 or 42 °C, at pH 5.0-9.0 (optimum pH 6.0-7.0) and in the presence of 0-8 g NaCl l(-1) (optimum 0-1 g l(-1)). The analysis of 16S rRNA gene sequences indicated that strain C3(T) was phylogenetically related to members of the genus Undibacterium, with similarities ranging from 94.7 to 96.5%. Strain C3(T) contained ubiquinone 8 as the major respiratory quinone. The major cellular fatty acids were summed feature 3 (C16:1?7c/C16:1?6c), C17:0 cyclo, straight-chain C16:0, C12:0 and C10:0, unsaturated C18:1?7c and hydroxylated fatty acids C10:0 3-OH and C12:0 2-OH. The polar lipids were mainly phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The polyamines were putrescine and 2-hydroxyputrescine. The DNA G+C content was 57.4 mol% (determined from Tm). Based on these results, it is concluded that strain C3(T) represents a novel species of the genus Undibacterium, for which the name Undibacterium terreum sp. nov. is proposed, with C3(T) (=CGMCC 1.10998(T)=NBRC 108789(T)) representing the type strain. PMID:23159755

Liu, Yi-Qian; Wang, Bao-Jun; Zhou, Nan; Liu, Shuang-Jiang

2013-06-01

296

Thermotunica guangxiensis gen. nov., sp. nov., isolated from mushroom residue compost.  

PubMed

A novel thermophilic actinomycete, designated AG2-7T, was isolated from mushroom residue compost in Guangxi University, Nanning, China. The strain grew optimally at 45-60 °C, at pH 7.0 and with 0-3.0% (w/v) NaCl. Vegetative mycelia were branched and whitish to pale yellow without fragmentation. Aerial mycelium was abundant, whitish and differentiated into long chains of spores, with a membranous structure or tunica partially covering the surface of aerial hyphae. The non-motile spores were oval in shape with a ridged surface. Strain AG-27T contained meso-diaminopimelic acid as the diagnostic diamino acid, and the whole-cell sugars were galactose and ribose. Major fatty acids were iso-C16:0 (27.51%), iso-C17:0 (10.47%) and anteiso-C17:0 (12.01%). MK-9(H4) was the predominant menaquinone. The polar phospholipids were diphosphatidylglycerol, ninhydrin-positive glycophospholipid, phosphatidylinositol, phosphatidylinositol mannoside, phosphatidylethanolamine, phosphatidylmethylethanolamine, an unknown phospholipid and unknown glucosamine-containing phospholipids. The G+C content of the genomic DNA was 63.6 mol%. 16S rRNA gene sequence analysis showed that the organism belonged to the family Pseudonocardiaceae, suborder Pseudonocardineae and showed more than 5% divergence from other members of the family. Based on the phenotypic and phylogenetic data, strain AG2-7T represents a novel species of a new genus in the family Pseudonocardiaceae, for which the name Thermotunica guangxiensis gen. nov., sp. nov. is proposed. The type strain of the type species is AG2-7T (=ATCC BAA-2499T=CGMCC 4.7099T). PMID:24488931

Wu, Hao; Lian, Yunpeng; Liu, Bin; Ren, Yanling; Qin, Peisheng; Huang, Fuchang

2014-05-01

297

Bacillus cihuensis sp. nov., isolated from rhizosphere soil of a plant in the Cihu area of Taiwan.  

PubMed

A Gram-positive, moderately halotolerant, rod-shaped, spore forming bacterium, designated strain FJAT-14515(T) was isolated from a soil sample in Cihu area, Taoyuan County, Taiwan. The strain grew at 10-35 °C (optimum at 30 °C), pH 5.7-9.0 (optimum at pH 7.0) and at salinities of 0-5 % (w/v) NaCl (optimum at 1 % w/v). The diagnostic diamino acid of the peptidoglycan of the isolated strain was meso-diaminopimelic acid and major respiratory isoprenoid quinone was MK-7. Major cellular fatty acids were anteiso-C15:0 (40.6 %), iso-C15:0 (20.7 %) and the DNA G+C content of strain FJAT-14515(T) was 37.1 mol %. A phylogenetic analysis based on 16S rRNA gene sequences indicated that strain FJAT-14515(T) belongs to the genus Bacillus, and was most closely related to the reference strains of Bacillus muralis DSM 16288(T) (97.6 %) and Bacillus simplex DSM 1321(T) (97.5 %). Levels of DNA-DNA relatedness between strain FJAT-14515(T) and the reference strains of B. muralis DSM 16288(T) and B. simplex DSM 1321(T) were 27.9 % ± 3.32 and 44.1 % ± 0.57, respectively. Therefore, on the basis of phenotypic, chemotaxonomic and genotypic properties, strain FJAT-14515(T) represents a novel species of the genus Bacillus, for which the name Bacillus cihuensis sp. nov. is proposed. The type strain is FJAT-14515(T) (=DSM 25969(T) = CGMCC 1.12697(T)). PMID:25256951

Liu, Bo; Liu, Guo-Hong; Sengonca, Cetin; Schumann, Peter; Wang, Ming-Kuang; Tang, Jian-Yang; Chen, Mei-Chun

2014-12-01

298

Pedobacter xixiisoli sp. nov., isolated from bank soil.  

PubMed

A Gram-stain-negative, rod-shaped, yellow, non-motile, aerobic bacterium (strain S27(T)) was isolated from bank soil of the Xixi wetland in Zhejiang province, PR China. Phylogenetic analysis, based on its 16S rRNA gene sequence, revealed that strain S27(T) could represent a novel species of the genus Pedobacter showing highest similarity to Pedobacter koreensis WPCB189(T) (95.45?%), followed by 'Pedobacter zeaxanthinifaciens' TDMA-5 (95.22?%). The temperature, pH and NaCl concentration ranges for growth were 6-37 °C (optimum 28 °C), pH 5.0-9.0 (optimum pH 7.5) and 0-3?% (w/v) [optimum 0.5?% (w/v)], respectively. The DNA G+C content was 36.1 mol%, MK-7 was the only respiratory quinone, and iso-C15?:?0, iso-C17?:?0 3-OH and summed feature 3 (C16?:?1?7c and/or iso-C15?:?0 2-OH) were the major fatty acids. These data all support the affiliation of strain S27(T) to the genus Pedobacter. The polar lipids of strain S27(T) comprised phosphatidylethanolamine, one unidentified aminophospholipid, four unidentified aminolipids and three unidentified lipids. However, strain S27(T) could be distinguished from other members of the genus Pedobacter due to its physiological and biochemical characteristics. Therefore, strain S27(T) represents a novel species of the genus Pedobacter, for which the name Pedobacter xixiisoli sp. nov. is proposed; the type strain is S27(T) (?=?CGMCC 1.12803(T)?=?NBRC 110388(T)). PMID:25106922

Zeng, Yanhua; Feng, Hao; Huang, Yili

2014-11-01

299

Isolation of oxalotrophic bacteria able to disperse on fungal mycelium.  

PubMed

A technique based on an inverted Petri dish system was developed for the growth and isolation of soil oxalotrophic bacteria able to disperse on fungal mycelia. The method is related to the 'fungal highways' dispersion theory in which mycelial fungal networks allow active movement of bacteria in soil. Quantification of this phenomenon showed that bacterial dispersal occurs preferentially in upper soil horizons. Eight bacteria and one fungal strain were isolated by this method. The oxalotrophic activity of the isolated bacteria was confirmed through calcium oxalate dissolution in solid selective medium. After separation of the bacteria-fungus couple, partial sequencing of the 16S and the ITS1 and ITS2 sequences of the ribosomal RNA genes were used for the identification of bacteria and the associated fungus. The isolated oxalotrophic bacteria included strains related to Stenotrophomonas, Achromobacter, Lysobacter, Pseudomonas, Agrobacterium, Cohnella, and Variovorax. The recovered fungus corresponded to Trichoderma sp. A test carried out to verify bacterial transport in an unsaturated medium showed that all the isolated bacteria were able to migrate on Trichoderma hyphae or glass fibers to re-colonize an oxalate-rich medium. The results highlight the importance of fungus-driven bacterial dispersal to understand the functional role of oxalotrophic bacteria and fungi in soils. PMID:24106816

Bravo, Daniel; Cailleau, Guillaume; Bindschedler, Saskia; Simon, Anaele; Job, Daniel; Verrecchia, Eric; Junier, Pilar

2013-11-01

300

Survey of Plant Drought-Resistance Promoting Bacteria from Populus euphratica Tree Living in Arid Area.  

PubMed

Two hundred and thirty-two bacterial strains were isolated from the rhizospheric soil of Populus euphratica which is the dominant tree living in extreme arid regions in northwest China. Some strains with plant growth-promoting bacteria related metabolic characteristics were able to promote drought resistance in plants after inoculation. Ten strains with the greatest effects increased the dry weight of wheat shoots from 0.5 to 34.4 %, and the surface area of the root systems from 12.56 to 212.17 % compared to the control after drought treatment whereas no obvious promoting effect was observed in normal water conditions. These 10 strains were identified to be of the genera Pseudomonas, Bacillus, Stenotrophomonas and Serratia by 16S rRNA (rrs) gene sequence alignment. Among these strains, Serratia sp. 1-9 and Pseudomonas sp. 5-23 were the two most effective strains. Both of them produced auxin and the production increased significantly when cultured under simulated drought conditions which are inferred to be the most plausible mechanism for their plant growth-promoting effect under drought stress. PMID:25320440

Wang, Shanshan; Ouyang, Liming; Ju, Xiangyang; Zhang, Lili; Zhang, Qin; Li, Yanbin

2014-12-01

301

Biogeochemical characterization of MC252 oil:sand aggregates on a coastal headland beach.  

PubMed

MC252 oil:sand aggregates, termed surface residue balls (SRBs), were sampled for physical, chemical and microbial characteristics from different tidal zones on a coastal headland beach in Louisiana, USA. Supratidal SRBs were smaller, had low moisture content, and salinities that were <2 ppt. Intertidal SRBs were hypersaline and had higher N and sulfate concentrations, consistent with regular tidal inundation. Crude oil components were highest in the intertidal "oil mat" SRBs with C1- and C2-phenanthrenes, C2- and C3-dibenzothiophenes comprising the majority of the PAH concentrations. In the other SRB categories, PAHs and alkanes were depleted and profiles were skewed toward higher molecular weight compounds. Oxygen microelectrode measurements demonstrated that saturated O2 is present immediately after wetting, but O2 consumption in the interior of the aggregate occurs after a few days. Microbial populations varied with position on the beach but sequences similar to known PAH-degrading taxa (Mycobacterium sp. and Stenotrophomonas sp.) were observed. PMID:24210008

Urbano, Marilany; Elango, Vijaikrishnah; Pardue, John H

2013-12-15

302

Intraspecific differences in bacterial responses to modelled reduced gravity  

NASA Technical Reports Server (NTRS)

AIMS: Bacteria are important residents of water systems, including those of space stations which feature specific environmental conditions, such as lowered effects of gravity. The purpose of this study was to compare responses with modelled reduced gravity of space station, water system bacterial isolates with other isolates of the same species. METHODS AND RESULTS: Bacterial isolates, Stenotrophomonas paucimobilis and Acinetobacter radioresistens, originally recovered from the water supply aboard the International Space Station (ISS) were grown in nutrient broth under modelled reduced gravity. Their growth was compared with type strains S. paucimobilis ATCC 10829 and A. radioresistens ATCC 49000. Acinetobacter radioresistens ATCC 49000 and the two ISS isolates showed similar growth profiles under modelled reduced gravity compared with normal gravity, whereas S. paucimobilis ATCC 10829 was negatively affected by modelled reduced gravity. CONCLUSIONS: These results suggest that microgravity might have selected for bacteria that were able to thrive under this unusual condition. These responses, coupled with impacts of other features (such as radiation resistance and ability to persist under very oligotrophic conditions), may contribute to the success of these water system bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: Water quality is a significant factor in many environments including the ISS. Efforts to remove microbial contaminants are likely to be complicated by the features of these bacteria which allow them to persist under the extreme conditions of the systems.

Baker, P. W.; Leff, L. G.

2005-01-01

303

Evidence for specificity of cultivable bacteria associated with arbuscular mycorrhizal fungal spores.  

PubMed

Bacteria associated with arbuscular mycorrhizal (AM) fungal spores may play functional roles in interactions between AM fungi, plant hosts and defence against plant pathogens. To study AM fungal spore-associated bacteria (AMB) with regard to diversity, source effects (AM fungal species, plant host) and antagonistic properties, we isolated AMB from surface-decontaminated spores of Glomus intraradices and Glomus mosseae extracted from field rhizospheres of Festuca ovina and Leucanthemum vulgare. Analysis of 385 AMB was carried out by fatty acid methyl ester (FAME) profile analysis, and some also identified using 16S rRNA gene sequence analysis. The AMB were tested for capacity to inhibit growth in vitro of Rhizoctonia solani and production of fluorescent siderophores. Half of the AMB isolates could be identified to species (similarity index 0.6) within 16 genera and 36 species. AMB were most abundant in the genera Arthrobacter and Pseudomonas and in a cluster of unidentified isolates related to Stenotrophomonas. The AMB composition was affected by AM fungal species and to some extent by plant species. The occurrence of antagonistic isolates depended on AM fungal species, but not plant host, and originated from G. intraradices spores. AM fungal spores appear to host certain sets of AMB, of which some can contribute to resistance by AM fungi against plant pathogens. PMID:18631178

Bharadwaj, Dharam Parkash; Lundquist, Per-Olof; Persson, Paula; Alström, Sadhna

2008-08-01

304

Effects of bacterial inoculants on the indigenous microbiome and secondary metabolites of chamomile plants.  

PubMed

Plant-associated bacteria fulfill important functions for plant growth and health. However, our knowledge about the impact of bacterial treatments on the host's microbiome and physiology is limited. The present study was conducted to assess the impact of bacterial inoculants on the microbiome of chamomile plants Chamomilla recutita (L.) Rauschert grown in a field under organic management in Egypt. Chamomile seedlings were inoculated with three indigenous Gram-positive strains (Streptomyces subrutilus Wbn2-11, Bacillus subtilis Co1-6, Paenibacillus polymyxa Mc5Re-14) from Egypt and three European Gram-negative strains (Pseudomonas fluorescens L13-6-12, Stenotrophomonas rhizophila P69, Serratia plymuthica 3Re4-18) already known for their beneficial plant-microbe interaction. Molecular fingerprints of 16S rRNA gene as well as real-time PCR analyses did not show statistically significant differences for all applied bacterial antagonists compared to the control. In contrast, a pyrosequencing analysis of the 16S rRNA gene libraries revealed significant differences in the community structure of bacteria between the treatments. These differences could be clearly shown by a shift within the community structure and corresponding beta-diversity indices. Moreover, B. subtilis Co1-6 and P. polymyxa Mc5Re-14 showed an enhancement of the bioactive secondary metabolite apigenin-7-O-glucoside. This indicates a possible new function of bacterial inoculants: to interact with the plant microbiome as well as to influence the plant metabolome. PMID:24600444

Schmidt, Ruth; Köberl, Martina; Mostafa, Amr; Ramadan, Elshahat M; Monschein, Marlene; Jensen, Kenneth B; Bauer, Rudolf; Berg, Gabriele

2014-01-01

305

Hessian Fly-Associated Bacteria: Transmission, Essentiality, and Composition  

PubMed Central

Plant-feeding insects have been recently found to use microbes to manipulate host plant physiology and morphology. Gall midges are one of the largest groups of insects that manipulate host plants extensively. Hessian fly (HF, Mayetiola destructor) is an important pest of wheat and a model system for studying gall midges. To examine the role of bacteria in parasitism, a systematic analysis of bacteria associated with HF was performed for the first time. Diverse bacteria were found in different developmental HF stages. Fluorescent in situ hybridization detected a bacteriocyte-like structure in developing eggs. Bacterial DNA was also detected in eggs by PCR using primers targeted to different bacterial groups. These results indicated that HF hosted different types of bacteria that were maternally transmitted to the next generation. Eliminating bacteria from the insect with antibiotics resulted in high mortality of HF larvae, indicating that symbiotic bacteria are essential for the insect to survive on wheat seedlings. A preliminary survey identified various types of bacteria associated with different HF stages, including the genera Enterobacter, Pantoea, Stenotrophomonas, Pseudomonas, Bacillus, Ochrobactrum, Acinetobacter, Alcaligenes, Nitrosomonas, Arcanobacterium, Microbacterium, Paenibacillus, and Klebsiella. Similar bacteria were also found specifically in HF-infested susceptible wheat, suggesting that HF larvae had either transmitted bacteria into plant tissue or brought secondary infection of bacteria to the wheat host. The bacteria associated with wheat seedlings may play an essential role in the wheat-HF interaction. PMID:21858016

Bansal, Raman; Hulbert, Scot; Schemerhorn, Brandi; Reese, John C.; Whitworth, R. Jeff; Stuart, Jeffrey J.; Chen, Ming-Shun

2011-01-01

306

Application of COMPOCHIP microarray to investigate the bacterial communities of different composts.  

PubMed

A microarray spotted with 369 different 16S rRNA gene probes specific to microorganisms involved in the degradation process of organic waste during composting was developed. The microarray was tested with pure cultures, and of the 30,258 individual probe-target hybridization reactions performed, there were only 188 false positive (0.62%) and 22 false negative signals (0.07%). Labeled target DNA was prepared by polymerase chain reaction amplification of 16S rRNA genes using a Cy5-labeled universal bacterial forward primer and a universal reverse primer. The COMPOCHIP microarray was applied to three different compost types (green compost, manure mix compost, and anaerobic digestate compost) of different maturity (2, 8, and 16 weeks), and differences in the microorganisms in the three compost types and maturity stages were observed. Multivariate analysis showed that the bacterial composition of the three composts was different at the beginning of the composting process and became more similar upon maturation. Certain probes (targeting Sphingobacterium, Actinomyces, Xylella/Xanthomonas/Stenotrophomonas, Microbacterium, Verrucomicrobia, Planctomycetes, Low G + C and Alphaproteobacteria) were more influential in discriminating between different composts. Results from denaturing gradient gel electrophoresis supported those of microarray analysis. This study showed that the COMPOCHIP array is a suitable tool to study bacterial communities in composts. PMID:18818861

Franke-Whittle, Ingrid H; Knapp, Brigitte A; Fuchs, Jacques; Kaufmann, Ruediger; Insam, Heribert

2009-04-01

307

Effect of chemotherapy on the microbiota and metabolome of human milk, a case report  

PubMed Central

Background Human milk is an important source of bacteria for the developing infant and has been shown to influence the bacterial composition of the neonatal gut, which in turn can affect disease risk later in life. Human milk is also an important source of nutrients, influencing bacterial composition but also directly affecting the host. While recent studies have emphasized the adverse effects of antibiotic therapy on the infant microbiota, the effects of maternal chemotherapy have not been previously studied. Here we report the effects of drug administration on the microbiota and metabolome of human milk. Methods Mature milk was collected every two weeks over a four month period from a lactating woman undergoing chemotherapy for Hodgkin’s lymphoma. Mature milk was also collected from healthy lactating women for comparison. Microbial profiles were analyzed by 16S sequencing and the metabolome by gas chromatography–mass spectrometry. Findings Chemotherapy caused a significant deviation from a healthy microbial and metabolomic profile, with depletion of genera Bifidobacterium, Eubacterium, Staphylococcus and Cloacibacterium in favor of Acinetobacter, Xanthomonadaceae and Stenotrophomonas. The metabolites docosahexaenoic acid and inositol known for their beneficial effects were also decreased. Conclusion With milk contents being critical for shaping infant immunity and development, consideration needs to be given to the impact of drugs administered to the mother and the long-term potential consequences for the health of the infant. PMID:25061513

2014-01-01

308

Beverages obtained from soda fountain machines in the U.S. contain microorganisms, including coliform bacteria.  

PubMed

Ninety beverages of three types (sugar sodas, diet sodas and water) were obtained from 20 self-service and 10 personnel-dispensed soda fountains, analyzed for microbial contamination, and evaluated with respect to U.S. drinking water regulations. A follow-up study compared the concentration and composition of microbial populations in 27 beverages collected from 9 soda fountain machines in the morning as well as in the afternoon. Ice dispensed from these machines was also examined for microbial contamination. While none of the ice samples exceeded U.S. drinking water standards, coliform bacteria was detected in 48% of the beverages and 20% had a heterotrophic plate count greater than 500cfu/ml. Statistical analyses revealed no difference in levels of microbial contamination between beverage types or between those dispensed from self-service and personnel-dispensed soda fountains. More than 11% of the beverages analyzed contained Escherichia coli and over 17% contained Chryseobacterium meningosepticum. Other opportunistic pathogenic microorganisms isolated from the beverages included species of Klebsiella, Staphylococcus, Stenotrophomonas, Candida, and Serratia. Most of the identified bacteria showed resistance to one or more of the 11 antibiotics tested. These findings suggest that soda fountain machines may harbor persistent communities of potentially pathogenic microorganisms which may contribute to episodic gastric distress in the general population and could pose a more significant health risk to immunocompromised individuals. These findings have important public health implications and signal the need for regulations enforcing hygienic practices associated with these beverage dispensers. PMID:19926155

White, Amy S; Godard, Renee D; Belling, Carolyn; Kasza, Victoria; Beach, Rebecca L

2010-01-31

309

Chronic Mycobacterium abscessus infection and lung function decline in cystic fibrosis  

PubMed Central

Background Although nontuberculous mycobacteria (NTM) are recognized pathogens in cystic fibrosis (CF), associations with clinical outcomes remain unclear. Methods Microbiological data was obtained from 1216 CF patients over 8 years (481±55 patients/year). Relationships to clinical outcomes were examined in the subset (n=271, 203±23 patients/year) with longitudinal data. Results Five hundred thirty-six of 4862 (11%) acid-fast bacilli (AFB) cultures grew NTM, with Mycobacterium abscessus (n=298, 55.6%) and Mycobacterium avium complex (n=190, 35.4%) most common. Associated bacterial cultures grew Stenotrophomonas or Aspergillus species more often when NTM were isolated (18.2% vs. 8.4% and 13.9% vs. 7.2%, respectively, p<0.01). After controlling for confounders, patients with chronic M. abscessus infection had greater rates of lung function decline than those with no NTM infection (?2.52 vs. ?1.64% predicted FEV1/year, p<0.05). Conclusions NTM infection is common in CF and associated with particular pathogens. Chronic M. abscessus infection is associated with increased lung function decline. PMID:20071249

Esther, Charles R.; Esserman, Denise A.; Gilligan, Peter; Kerr, Alan; Noone, Peadar G.

2013-01-01

310

Characterization of Phragmites cummunis rhizosphere bacterial communities and metabolic products during the two stage sequential treatment of post methanated distillery effluent by bacteria and wetland plants.  

PubMed

This study deals with the characterization of rhizosphere bacterial communities and metabolic products produced during the two stage sequential treatment of post methanated distillery effluent by bacteria and constructed wetland plants. Results showed that bacterial treatment followed by wetland plants (Phragmites cummunis) resulted 94.5% and 96.0% reduction in BOD and COD values, respectively. The PCR-RFLP analysis showed the presence of Stenotrophomonas, Enterobacter, Pantoea, Acinetobacter and Klebsiella sp., as dominant rhizosphere bacterial communities which play an important role in degradation and decolorization of PMDE in wetland treatment system. Further, the LC-MS-MS and other spectrophotometric analysis have shown that most of the pollutants detected in untreated PMDE were diminished from bacteria and wetland plant treated PMDE indicating that bacteria and wetland plant rhizosphere microbes utilized them as carbon, nitrogen and energy source. While, methylbenzene, furfuryl alcohol, and 4-vinyl-2-methoxyphenol were detected as metabolites in bacteria and hexadecanol in wetland plant rhizosphere treated PMDE. PMID:22047662

Chandra, Ram; Bharagava, Ram Naresh; Kapley, Atya; Purohit, Hemant J

2012-01-01

311

Silanimonas lenta gen. nov., sp. nov., a slightly thermophilic and alkaliphilic gammaproteobacterium isolated from a hot spring.  

PubMed

A moderately thermophilic aerobic bacterium, strain 25-4T, was isolated from a hot spring at Baekdoo Mountain in Korea. The cells were Gram-negative, motile rods each having a polar flagellum. Analysis of the 16S rRNA gene sequence indicated that the strain represented a new lineage within the family 'Xanthomonadaceae' of the 'Gammaproteobacteria', being most closely related to the genera Thermomonas, Xanthomonas, Luteimonas, Pseudoxanthomonas, Stenotrophomonas and Xylella and having 16S rRNA gene sequence similarities to the most related species of the genera of between 92.9 and 94.4 %. The strain contained Q-8 as the major isoprenoid quinone and had a fatty acid profile with predominant iso-branched fatty acids. Growth occurred at pH 6.0-10, with an optimum at pH 9.0, and at 25-53 degrees C, with an optimum at 47 degrees C. The G+C content of the genomic DNA was 50.7 mol%. On the basis of phylogenetic analyses and its phenotypic characteristics, strain 25-4T belongs to a new genus, Silanimonas gen. nov., within the 'Gammaproteobacteria'. The sole species of this genus is Silanimonas lenta sp. nov. (type strain, 25-4T=DSM 16282T=KCTC 12236T). PMID:15653905

Lee, Eun Mi; Jeon, Che Ok; Choi, Inpyo; Chang, Kyu-Seob; Kim, Chang-Jin

2005-01-01

312

The role of nutrients in the biodegradation of 2,4,6-trinitrotoluene in liquid and soil.  

PubMed

The widely used explosive 2,4,6-trinitrotoluene (TNT) has residues that are potentially explosive, toxic, and mutagenic. TNT and other explosives can be degraded by microorganisms; however, biostimulation is needed for process efficiency. To investigate the effectiveness of using biostimulation to degrade TNT, we added varying concentrations of a nutrient amendment consisting of inorganic salts, plant extracts, and molasses to soil and liquid media. For the inoculum we used a consortium of bacteria AM 06 that had exhibited the ability to degrade TNT and which had been previously isolated from explosives-contaminated soils. Phylogenetically, the clones clustered into seven different genera: Klebsiella, Raoultella, Serratia, Stenotrophomonas, Pseudoxanthomonas, Achromobacter and Pseudomonas. The addition of AM 06 consortium to a liquid environment along with 100% nutrient amendment decreased the amount of TNT (and its degradation products) by up to 90% after 14 days incubation. At the total amount of TNT was less than 100 mg/l, the concentration of TNT did not influence the amount of sugar consumed by the bacteria consortium. In soil media, the TNT degradation process was dependent on the concentration of nutrient amendment added. At higher initial concentrations of TNT (500 mg/kg), bioaugmentation (i.e., addition of bacteria inoculum) had a demonstrated effect, especially when nutrient concentrations of 50% and 100% were added to the soil. Findings of this study could further the understanding of the TNT biodegradation processes in water and soil and provide for optimization of the technological conditions for bioremediation. PMID:22245864

Muter, Olga; Potapova, Katrina; Limane, Baiba; Sproge, Kristine; Jakobsone, Ida; Cepurnieks, Guntis; Bartkevics, Vadims

2012-05-15

313

Community Shifts in the Surface Microbiomes of the Coral Porites astreoides with Unusual Lesions  

PubMed Central

Apical lesions on Porites astreoides were characterized by the appearance of a thin yellow band, which was preceded by bleaching of the coral tissues and followed by a completely denuded coral skeleton, which often harbored secondary macroalgal colonizers. These characteristics have not been previously described in Porites and do not match common Caribbean coral diseases. The lesions were observed only in warmer months and at shallow depths on the fore reef in Belize. Analysis of the microbial community composition based on the V4 hypervariable region of 16S ribosomal RNA genes revealed that the surface microbiomes associated with nonsymptomatic corals were dominated by the members of the genus Endozoicomonas, consistent with other studies. Comparison of the microbiomes of nonsymptomatic and lesioned coral colonies sampled in July and September revealed two distinct groups, inconsistently related to the disease state of the coral, but showing some temporal signal. The loss of Endozoicomonas was characteristic of lesioned corals, which also harbored potential opportunistic pathogens such as Alternaria, Stenotrophomonas, and Achromobacter. The presence of lesions in P. astreoides coincided with a decrease in the relative abundance of Endozoicomonas, rather than the appearance of specific pathogenic taxa. PMID:24937478

Meyer, Julie L.; Paul, Valerie J.; Teplitski, Max

2014-01-01

314

Isolation and Identification of Cellulolytic Bacteria from the Gut of Holotrichia parallela Larvae (Coleoptera: Scarabaeidae).  

PubMed

In this study, 207 strains of aerobic and facultatively anaerobic cellulolytic bacteria were isolated from the gut of Holotrichia parallela larvae. These bacterial isolates were assigned to 21 genotypes by amplified ribosomal DNA restriction analysis (ARDRA). A partial 16S rDNA sequence analysis and standard biochemical and physiological tests were used for the assignment of the 21 representative isolates. Our results show that the cellulolytic bacterial community is dominated by the Proteobacteria (70.05%), followed by the Actinobacteria (24.15%), the Firmicutes (4.35%), and the Bacteroidetes (1.45%). At the genus level, Gram-negative bacteria including Pseudomonas, Ochrobactrum, Rhizobium, Cellulosimicrobium, and Microbacterium were the predominant groups, but members of Bacillus, Dyadobacter, Siphonobacter, Paracoccus, Kaistia, Devosia, Labrys, Ensifer, Variovorax, Shinella, Citrobacter, and Stenotrophomonas were also found. Furthermore, our results suggest that a significant amount of bacterial diversity exists among the cellulolytic bacteria, and that Siphonobacter aquaeclarae, Cellulosimicrobium funkei, Paracoccus sulfuroxidans, Ochrobactrum cytisi, Ochrobactrum haematophilum, Kaistia adipata, Devosia riboflavina, Labrys neptuniae, Ensifer adhaerens, Shinella zoogloeoides, Citrobacter freundii, and Pseudomonas nitroreducens are reported to be cellulolytic for the first time in this study. Our results indicate that the scarab gut is an attractive source for the study of novel cellulolytic microorganisms and enzymes useful for cellulose degradation. PMID:22489111

Huang, Shengwei; Sheng, Ping; Zhang, Hongyu

2012-01-01

315

Herbivore exploits orally secreted bacteria to suppress plant defenses.  

PubMed

Induced plant defenses in response to herbivore attack are modulated by cross-talk between jasmonic acid (JA)- and salicylic acid (SA)-signaling pathways. Oral secretions from some insect herbivores contain effectors that overcome these antiherbivore defenses. Herbivores possess diverse microbes in their digestive systems and these microbial symbionts can modify plant-insect interactions; however, the specific role of herbivore-associated microbes in manipulating plant defenses remains unclear. Here, we demonstrate that Colorado potato beetle (Leptinotarsa decemlineata) larvae exploit bacteria in their oral secretions to suppress antiherbivore defenses in tomato (Solanum lycopersicum). We found that antibiotic-untreated larvae decreased production of JA and JA-responsive antiherbivore defenses, but increased SA accumulation and SA-responsive gene expression. Beetles benefit from down-regulating plant defenses by exhibiting enhanced larval growth. In SA-deficient plants, suppression was not observed, indicating that suppression of JA-regulated defenses depends on the SA-signaling pathway. Applying bacteria isolated from larval oral secretions to wounded plants confirmed that three microbial symbionts belonging to the genera Stenotrophomonas, Pseudomonas, and Enterobacter are responsible for defense suppression. Additionally, reinoculation of these bacteria to antibiotic-treated larvae restored their ability to suppress defenses. Flagellin isolated from Pseudomonas sp. was associated with defense suppression. Our findings show that the herbivore exploits symbiotic bacteria as a decoy to deceive plants into incorrectly perceiving the threat as microbial. By interfering with the normal perception of herbivory, beetles can evade antiherbivore defenses of its host. PMID:24019469

Chung, Seung Ho; Rosa, Cristina; Scully, Erin D; Peiffer, Michelle; Tooker, John F; Hoover, Kelli; Luthe, Dawn S; Felton, Gary W

2013-09-24

316

Influence of Temperature and Inoculum Density of Fusarium oxysporum f. sp. ciceris on Suppression of Fusarium Wilt of Chickpea by Rhizosphere Bacteria.  

PubMed

The effects of temperature and inoculum density of Fusarium oxysporum f. sp. ciceris race 5 on suppression of Fusarium wilt in chickpea (Cicer arietinum) cv. PV 61 by seed and soil treatments with rhizobacteria isolated from the chickpea rhizosphere were studied in a model system. Disease development over a range of temperatures (20, 25, and 30 degrees C) and inoculum densities (25 to 1,000 chlamydospores per gram of soil) was described by the Gompertz model. The Gompertz relative rate of disease progress and final amount of disease increased exponentially and monomolecularly, respectively, with increasing inoculum densities. Disease development was greater at 25 degrees C compared with 20 and 30 degrees C. At 20 and 30 degrees C, disease development was greater at 250 to 1,000 chlamydospores per gram of soil compared with 25 to 100 chlamydospores per gram of soil. At 25 degrees C, increasing inoculum densities of the pathogen did not influence disease. Nineteen Bacillus, Paenibacillus, Pseudomonas, and Stenotrophomonas spp. out of 23 bacterial isolates tested inhibited F. oxysporum f. sp. ciceris in vitro. Pseudomonas fluorescens RGAF 19 and RG 26, which did not inhibit the pathogen, showed the greatest Fusarium wilt suppression. Disease was suppressed only at 20 or 30 degrees C and at inoculum densities below 250 chlamydospores per gram of soil. Bacterial treatments increased the time to initial symptoms, reduced the Gompertz relative rate of disease progress, and reduced the overall amount of disease developed. PMID:18944039

Landa, B B; Navas-Cortés, J A; Hervás, A; Jiménez-Díaz, R M

2001-08-01

317

[Isolation of two endophytic phenanthrene-degrading strains and their degradation capacity].  

PubMed

Two endophytic bacterial strains, which could degrade high concentration (up to 200 mg.L-1) of phenanthrene in liquid, were isolated from plants grown in PAHs-contaminated soils by the selective. enrichment culture. According to the results of morphology, physiology and the phylogenetic analyses of 16S rDNA sequence, stain P1 was identified as Stenotrophomonas sp. , and strain P3 was identified as Pseudomonas sp.. Two strains were aerobic bacteria, the degradation rates of phenanthrene (100 mg.L-1) by strain P1 and strain P3 were all greater than 90% at 28 degrees C on the rotation shaker at 150 r.min-1 for 7 days. The degradation rates of phenanthrene by two strains were greater than 70% when cultivated under the conditions as: 20-30 degrees C , pH 6-8, 0%-4% NaCl, 10-30 mL/100 mL inventory. It suggested that the optimum culture condition was: 30 degrees C, pH 7.0, NaCl< or =4% , inventory < or = 30 mL/100 mL flask. Through comprehensive comparison analyses on the degradation capacity of two strains, it showed that the tolerance of strain P1 to high temperature was higher than that of str ain P3, while the tolerance of strain P3 to pH change and anoxic condition was higher than that of strain P1. PMID:23668150

Ni, Xue; Liu, Juan; Gao, Yan-Zheng; Zhu, Xue-Zhu; Sun, Kai

2013-02-01

318

Plant age and genotype affect the bacterial community composition in the tuber rhizosphere of field-grown sweet potato plants.  

PubMed

The hypothesis that sweet potato genotypes containing different starch yields in their tuberous roots can affect the bacterial communities present in the rhizosphere (soil adhering to tubers) was tested in this study. Tuberous roots of field-grown sweet potato of genotypes IPB-149 (commercial genotype), IPB-052, and IPB-137 were sampled three and six months after planting and analyzed by denaturing gradient gel electrophoresis (DGGE) and pyrosequencing analysis of 16S rRNA genes PCR-amplified from total community DNA. The statistical analysis of the DGGE fingerprints showed that both plant age and genotypes influenced the bacterial community structure in the tuber rhizosphere. Pyrosequencing analysis showed that the IPB-149 and IPB-052 (both with high starch content) displayed similar bacterial composition in the tuber rhizosphere, while IPB-137 with the lowest starch content was distinct. In comparison with bulk soil, higher 16S rRNA gene copy numbers (qPCR) and numerous genera with significantly increased abundance in the tuber rhizosphere of IPB-137 (Sphingobium, Pseudomonas, Acinetobacter, Stenotrophomonas, Chryseobacterium) indicated a stronger rhizosphere effect. The genus Bacillus was strongly enriched in the tuber rhizosphere samples of all sweet potato genotypes studied, while other genera showed a plant genotype-dependent abundance. This is the first report on the molecular identification of bacteria being associated with the tuber rhizosphere of different sweet potato genotypes. PMID:24597529

Marques, Joana M; da Silva, Thais F; Vollu, Renata E; Blank, Arie F; Ding, Guo-Chun; Seldin, Lucy; Smalla, Kornelia

2014-05-01

319

Characterization of the pigment xanthomonadin in the bacterial genus Xanthomonas using micro- and resonance Raman spectroscopy  

NASA Astrophysics Data System (ADS)

We used micro- and resonance Raman spectroscopy with 785 nm and 514.5 nm laser excitation, respectively, to characterize a plant pathogenic bacteria, Xanthomonas axonopodis pv. dieffenbachiae D150. The bacterial genus Xathomonas is closely related to bacterial genus Stenotrophomonas that causes an infection in humans. This study has identified for the first time the unique Raman spectra of the carotenoid-like pigment xanthomonadin of the Xanthomonas strain. Xanthomonadin is a brominated aryl-polyene pigment molecule similar to carotenoids. Further studies were conducted using resonance Raman spectroscopy with 514.5 nm laser excitation on several strains of the bacterial genus Xanthomonas isolated from numerous plants from various geographical locations. The current study revealed that the Raman bands representing the vibrations (v1, v2, v3) of the polyene chain of xanthomonadin are 1003-1005 (v3), 1135-1138 (v2), and 1530 (v1). Overtone bands representing xanthomonadin were identified as 2264-2275 (2v2), and combinational bands at 2653-2662 (v1+ v2). The findings from this study validate our previous finding that the Raman fingerprints of xanthomonadin are unique for the genus Xanthomonas. This facilitates rapid identification (~5 minutes) of Xanthomonas spp. from bacterial culture plates. The xanthomonadin marker is different from Raman markers of many other bacterial genus including Agrobacterium, Bacillus, Clavibacter, Enterobacter, Erwinia, Microbacterium, Paenibacillus, and Ralstonia. This study also identified Xanthomonas spp. from bacterial strains isolated from a diseased wheat sample on a culture plate.

Paret, Mathews L.; Sharma, Shiv K.; Misra, Anupam K.; Acosta, Tayro; deSilva, Asoka S.; Vowell, Tomie; Alvarez, Anne M.

2012-06-01

320

Bioremediation of heavy metal-contaminated effluent using optimized activated sludge bacteria  

NASA Astrophysics Data System (ADS)

Removal of heavy metals from contaminated domestic-industrial effluent using eight resistant indigenous bacteria isolated from acclimatized activated sludge was investigated. Molecular identification using 16S rDNA amplification revealed that all strains were Gram-negative among which two were resistant to each of copper, cadmium and cobalt while one was resistant to each of chromium and the heavy metal mixture. They were identified as Enterobacter sp. (Cu1), Enterobacter sp. (Cu2), Stenotrophomonas sp. (Cd1), Providencia sp. (Cd2), Chryseobacterium sp. (Co1), Comamonas sp. (Co2), Ochrobactrum sp. (Cr) and Delftia sp. (M1) according to their resistance pattern. Strains Cu1, Cd1, Co2 and Cr were able to resist 275 mg Cu/l, 320 mg Cd/l, 140 mg Co/l and 29 mg Cr/l respectively. The four resistant strains were used as a mixture to remove heavy metals (elevated concentrations) and reduce the organic load of wastewater effluent. Results revealed that using the proposed activated sludge with the resistant bacterial mixture was more efficient for heavy metal removal compared to the activated sludge alone. It is therefore recommended that the proposed activated sludge system augmented with the acclimatized strains is the best choice to ensure high treatment efficiency and performance under metal stresses especially when industrial effluents are involved.

Bestawy, Ebtesam El.; Helmy, Shacker; Hussien, Hany; Fahmy, Mohamed; Amer, Ranya

2013-03-01

321

Empirical Treatment of Highly Suspected Nontuberculous Mycobacteria Infections Following Aesthetic Procedures  

PubMed Central

Background Infection caused by nontuberculous mycobacteria (NTM) has been increasing. Awareness of this infection is crucial yet problematic. Delayed management may lead to destructive results. We empirically treated a series of patients with clinical suspicion of NTM infection prior to the identification of the pathogen. Methods A total of 12 patients who developed surgical site infections between January 2011 and February 2014 were reviewed. Patients with a skin and subcutaneous infection resistant to standard management over two weeks, and previous history of aesthetic procedures within three months were regarded as highly suspected of having an NTM infection. A variety of diagnostic modalities were examined simultaneously, along with starting empirical treatment including a combination of clarithromycin and moxifloxacin, and surgical debridement. Results All wounds healed completely within 4 weeks. The mean follow-up duration was 7.2 months, and none of the patients developed relapse. Specific NTM pathogens were identified in six patients. Eight patients showed caseating granuloma implying an NTM infection. One patient showed an uncommon Stenotrophomonas infection, which was successfully treated. Three patients had no evidence of a pathogen despite repeated microbial tests. Complications such as scarring, pigmentation, and disfigurement were common in all the patients. Conclusions NTM should be considered in the differential diagnosis of an unusual skin and soft-tissue infection. We propose an empirical regimen of clarithromycin and moxifloxacin as an efficient treatment option for an NTM infection.

Kim, Hyung Rok; Kim, Deok Woo; Hwang, Na Hyun; Shon, Yoo Seok; Lee, Byung Il; Park, Seung-Ha

2014-01-01

322

Abattoirs as Non-Hospital Source of Extended Spectrum Beta Lactamase Producers: Confirmed by the Double Disc Synergy Test and Characterized by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry  

PubMed Central

In this study, the presence of extended spectrum beta lactamase (ESBL) producing organisms in abattoirs, a non-hospital community was investigated. The presence of ESBL-producing phenotypes was confirmed by the Double Disc Synergy Test (DDST). Out of the 99 isolates screened for ESBL, 28 (28.3%) were confirmed positive. The positive isolates were characterised by using Matrix-Assisted Laser Desorption/Ionization Time of flight Mass Spectrometry. 50% of the isolates were Pseudomonas spp., the rest were different species of Acinetobacter, Stenotrophomonas and Achromobacter. Pseudomonas monteilli and Pseudomonas putida were the most occurring in the intestine. The entire positive ESBL producers were subjected to plasmid curing to ascertain the location of the resistant marker. The result of the plasmid curing indicated that the resistant genes were chromosomally borne. The findings have therefore established the presence of ESBL producing organisms in the gut of animals from abattoirs and the table were the meat are sold, and its rate of occurrence is comparable to hospital ICUs. Abattoir communities could probably be a source of human infection with ESBL expressing pathogens and possible transfer to non-ESBL producers. PMID:24728403

Ikegbunam, Moses Nkechukwu; Anagu, Linda Onyeka; Iroha, Ifeanyi R.; Ejikeugwu, Chika Ebiye; Esimone, Charles Okey

2014-01-01

323

Calcite Biomineralization by Bacterial Isolates from the Recently Discovered Pristine Karstic Herrenberg Cave  

PubMed Central

Karstic caves represent one of the most important subterranean carbon storages on Earth and provide windows into the subsurface. The recent discovery of the Herrenberg Cave, Germany, gave us the opportunity to investigate the diversity and potential role of bacteria in carbonate mineral formation. Calcite was the only mineral observed by Raman spectroscopy to precipitate as stalactites from seepage water. Bacterial cells were found on the surface and interior of stalactites by confocal laser scanning microscopy. Proteobacteria dominated the microbial communities inhabiting stalactites, representing more than 70% of total 16S rRNA gene clones. Proteobacteria formed 22 to 34% of the detected communities in fluvial sediments, and a large fraction of these bacteria were also metabolically active. A total of 9 isolates, belonging to the genera Arthrobacter, Flavobacterium, Pseudomonas, Rhodococcus, Serratia, and Stenotrophomonas, grew on alkaline carbonate-precipitating medium. Two cultures with the most intense precipitate formation, Arthrobacter sulfonivorans and Rhodococcus globerulus, grew as aggregates, produced extracellular polymeric substances (EPS), and formed mixtures of calcite, vaterite, and monohydrocalcite. R. globerulus formed idiomorphous crystals with rhombohedral morphology, whereas A. sulfonivorans formed xenomorphous globular crystals, evidence for taxon-specific crystal morphologies. The results of this study highlighted the importance of combining various techniques in order to understand the geomicrobiology of karstic caves, but further studies are needed to determine whether the mineralogical biosignatures found in nutrient-rich media can also be found in oligotrophic caves. PMID:22179248

Rusznyak, Anna; Akob, Denise M.; Nietzsche, Sandor; Eusterhues, Karin; Totsche, Kai Uwe; Neu, Thomas R.; Frosch, Torsten; Popp, Jurgen; Keiner, Robert; Geletneky, Jorn; Katzschmann, Lutz; Schulze, Ernst-Detlef

2012-01-01

324

Bioremediation of Hydrocarbons Contaminating Sewage Effluent Using Man-made Biofilms: Effects of Some Variables.  

PubMed

Biofilm samples were established on glass slides by submerging them in oil-free and oil-containing sewage effluent for a month. In batch cultures, such biofilms were effective in removing crude oil, pure n-hexadecane, and pure phenanthrene contaminating sewage effluent. The amounts of the removed hydrocarbons increased with increasing biofilm surface area exposed to the effluent. On the other hand, addition of the reducing agent thioglycollate dramatically inhibited the hydrocarbon bioremediation potential of the biofilms. The same biofilm samples removed contaminating hydrocarbons effectively in three successive batch bioremediation cycles but started to become less effective in the cycles thereafter, apparently due to mechanical biofilm loss during successive transfers. As major hydrocarbonoclastic bacteria, the biofilms harbored species belonging to the genera Pseudomonas, Microvirga, Zavarzinia, Mycobacterium, Microbacterium, Stenotrophomonas, Gordonia, Bosea, Sphingobium, Brachybacterium, and others. The nitrogen fixer Azospirillum brasilense and the microalga Ochromonas distigma were also present; they seemed to enrich the biofilms, with nitrogenous compounds and molecular oxygen, respectively, which are known to enhance microbiological hydrocarbon degradation. It was concluded that man-made biofilms based upon sewage microflora are promising tools for bioremediation of hydrocarbons contaminating sewage effluent. PMID:25146193

Al-Mailem, D M; Kansour, M K; Radwan, S S

2014-11-01

325

Pyrosequencing Reveals the Influence of Organic and Conventional Farming Systems on Bacterial Communities  

PubMed Central

It has been debated how different farming systems influence the composition of soil bacterial communities, which are crucial for maintaining soil health. In this research, we applied high-throughput pyrosequencing of V1 to V3 regions of bacterial 16S rRNA genes to gain further insight into how organic and conventional farming systems and crop rotation influence bulk soil bacterial communities. A 2×2 factorial experiment consisted of two agriculture management systems (organic versus conventional) and two crop rotations (flax-oat-fababean-wheat versus flax-alfalfa-alfalfa-wheat) was conducted at the Glenlea Long-Term Crop Rotation and Management Station, which is Canada’s oldest organic-conventional management study field. Results revealed that there is a significant difference in the composition of bacterial genera between organic and conventional management systems but crop rotation was not a discriminator factor. Organic farming was associated with higher relative abundance of Proteobacteria, while Actinobacteria and Chloroflexi were more abundant in conventional farming. The dominant genera including Blastococcus, Microlunatus, Pseudonocardia, Solirubrobacter, Brevundimonas, Pseudomonas, and Stenotrophomonas exhibited significant variation between the organic and conventional farming systems. The relative abundance of bacterial communities at the phylum and class level was correlated to soil pH rather than other edaphic properties. In addition, it was found that Proteobacteria and Actinobacteria were more sensitive to pH variation. PMID:23284808

Li, Ru; Khafipour, Ehsan; Krause, Denis O.; Entz, Martin H.; de Kievit, Teresa R.; Fernando, W. G. Dilantha

2012-01-01

326

NeutroPhase® in chronic non-healing wounds  

PubMed Central

Chronic non-healing wounds, such as venous stasis ulcers, diabetic ulcers, and pressure ulcers are serious unmet medical needs that affect a patient’s morbidity and mortality. Common pathogens observed in chronic non-healing wounds are Staphylococcus including MRSA, Pseudomonas, Enterobacter, Stenotrophomonas, and Serratia spp. Topical and systemically administered antibiotics do not adequately decrease the level of bacteria or the associated biofilm in chronic granulating wounds and the use of sub-lethal concentrations of antibiotics can lead to resistant phenotypes. Furthermore, topical antiseptics may not be fully effective and can actually impede wound healing. We show 5 representative examples from our more than 30 clinical case studies using NeutroPhase® as an irrigation solution with chronic non-healing wounds with and without the technique of negative pressure wound therapy (NPWT). NeutroPhase® is pure 0.01% hypochlorous acid (i.e. >97% relative molar distribution of active chlorine species as HOCl) in a 0.9% saline solution at pH 4-5 and is stored in glass containers. NovaBay has three FDA cleared 510(k)s. Patients showed a profound improvement and marked accelerated rates of wound healing using NeutroPhase® with and without NPWT. NeutroPhase® was non-toxic to living tissues. PMID:23272294

Crew, John; Varilla, Randell; Rocas, Thomas Allandale; Debabov, Dmitri; Wang, Lu; Najafi, Azar; Rani, Suriani Abdul; Najafi, Ramin (Ron); Anderson, Mark

2012-01-01

327

Isolation and Identification of Cellulolytic Bacteria from the Gut of Holotrichia parallela Larvae (Coleoptera: Scarabaeidae)  

PubMed Central

In this study, 207 strains of aerobic and facultatively anaerobic cellulolytic bacteria were isolated from the gut of Holotrichia parallela larvae. These bacterial isolates were assigned to 21 genotypes by amplified ribosomal DNA restriction analysis (ARDRA). A partial 16S rDNA sequence analysis and standard biochemical and physiological tests were used for the assignment of the 21 representative isolates. Our results show that the cellulolytic bacterial community is dominated by the Proteobacteria (70.05%), followed by the Actinobacteria (24.15%), the Firmicutes (4.35%), and the Bacteroidetes (1.45%). At the genus level, Gram-negative bacteria including Pseudomonas, Ochrobactrum, Rhizobium, Cellulosimicrobium, and Microbacterium were the predominant groups, but members of Bacillus, Dyadobacter, Siphonobacter, Paracoccus, Kaistia, Devosia, Labrys, Ensifer, Variovorax, Shinella, Citrobacter, and Stenotrophomonas were also found. Furthermore, our results suggest that a significant amount of bacterial diversity exists among the cellulolytic bacteria, and that Siphonobacter aquaeclarae, Cellulosimicrobium funkei, Paracoccus sulfuroxidans, Ochrobactrum cytisi, Ochrobactrum haematophilum, Kaistia adipata, Devosia riboflavina, Labrys neptuniae, Ensifer adhaerens, Shinella zoogloeoides, Citrobacter freundii, and Pseudomonas nitroreducens are reported to be cellulolytic for the first time in this study. Our results indicate that the scarab gut is an attractive source for the study of novel cellulolytic microorganisms and enzymes useful for cellulose degradation. PMID:22489111

Huang, Shengwei; Sheng, Ping; Zhang, Hongyu

2012-01-01

328

Effects of bacterial inoculants on the indigenous microbiome and secondary metabolites of chamomile plants  

PubMed Central

Plant-associated bacteria fulfill important functions for plant growth and health. However, our knowledge about the impact of bacterial treatments on the host's microbiome and physiology is limited. The present study was conducted to assess the impact of bacterial inoculants on the microbiome of chamomile plants Chamomilla recutita (L.) Rauschert grown in a field under organic management in Egypt. Chamomile seedlings were inoculated with three indigenous Gram-positive strains (Streptomyces subrutilus Wbn2-11, Bacillus subtilis Co1-6, Paenibacillus polymyxa Mc5Re-14) from Egypt and three European Gram-negative strains (Pseudomonas fluorescens L13-6-12, Stenotrophomonas rhizophila P69, Serratia plymuthica 3Re4-18) already known for their beneficial plant-microbe interaction. Molecular fingerprints of 16S rRNA gene as well as real-time PCR analyses did not show statistically significant differences for all applied bacterial antagonists compared to the control. In contrast, a pyrosequencing analysis of the 16S rRNA gene libraries revealed significant differences in the community structure of bacteria between the treatments. These differences could be clearly shown by a shift within the community structure and corresponding beta-diversity indices. Moreover, B. subtilis Co1-6 and P. polymyxa Mc5Re-14 showed an enhancement of the bioactive secondary metabolite apigenin-7-O-glucoside. This indicates a possible new function of bacterial inoculants: to interact with the plant microbiome as well as to influence the plant metabolome. PMID:24600444

Schmidt, Ruth; Koberl, Martina; Mostafa, Amr; Ramadan, Elshahat M.; Monschein, Marlene; Jensen, Kenneth B.; Bauer, Rudolf; Berg, Gabriele

2014-01-01

329

Bacterial Endophytic Communities in the Grapevine Depend on Pest Management  

PubMed Central

Microbial plant endophytes are receiving ever-increasing attention as a result of compelling evidence regarding functional interaction with the host plant. Microbial communities in plants were recently reported to be influenced by numerous environmental and anthropogenic factors, including soil and pest management. In this study we used automated ribosomal intergenic spacer analysis (ARISA) fingerprinting and pyrosequencing of 16S rDNA to assess the effect of organic production and integrated pest management (IPM) on bacterial endophytic communities in two widespread grapevines cultivars (Merlot and Chardonnay). High levels of the dominant Ralstonia, Burkholderia and Pseudomonas genera were detected in all the samples We found differences in the composition of endophytic communities in grapevines cultivated using organic production and IPM. Operational taxonomic units (OTUs) assigned to the Mesorhizobium, Caulobacter and Staphylococcus genera were relatively more abundant in plants from organic vineyards, while Ralstonia, Burkholderia and Stenotrophomonas were more abundant in grapevines from IPM vineyards. Minor differences in bacterial endophytic communities were also found in the grapevines of the two cultivars. PMID:25387008

Campisano, Andrea; Antonielli, Livio; Pancher, Michael; Yousaf, Sohail; Pindo, Massimo; Pertot, Ilaria

2014-01-01

330

Calcite biomineralization by bacterial isolates from the recently discovered pristine karstic herrenberg cave.  

PubMed

Karstic caves represent one of the most important subterranean carbon storages on Earth and provide windows into the subsurface. The recent discovery of the Herrenberg Cave, Germany, gave us the opportunity to investigate the diversity and potential role of bacteria in carbonate mineral formation. Calcite was the only mineral observed by Raman spectroscopy to precipitate as stalactites from seepage water. Bacterial cells were found on the surface and interior of stalactites by confocal laser scanning microscopy. Proteobacteria dominated the microbial communities inhabiting stalactites, representing more than 70% of total 16S rRNA gene clones. Proteobacteria formed 22 to 34% of the detected communities in fluvial sediments, and a large fraction of these bacteria were also metabolically active. A total of 9 isolates, belonging to the genera Arthrobacter, Flavobacterium, Pseudomonas, Rhodococcus, Serratia, and Stenotrophomonas, grew on alkaline carbonate-precipitating medium. Two cultures with the most intense precipitate formation, Arthrobacter sulfonivorans and Rhodococcus globerulus, grew as aggregates, produced extracellular polymeric substances (EPS), and formed mixtures of calcite, vaterite, and monohydrocalcite. R. globerulus formed idiomorphous crystals with rhombohedral morphology, whereas A. sulfonivorans formed xenomorphous globular crystals, evidence for taxon-specific crystal morphologies. The results of this study highlighted the importance of combining various techniques in order to understand the geomicrobiology of karstic caves, but further studies are needed to determine whether the mineralogical biosignatures found in nutrient-rich media can also be found in oligotrophic caves. PMID:22179248

Rusznyák, Anna; Akob, Denise M; Nietzsche, Sándor; Eusterhues, Karin; Totsche, Kai Uwe; Neu, Thomas R; Frosch, Torsten; Popp, Jürgen; Keiner, Robert; Geletneky, Jörn; Katzschmann, Lutz; Schulze, Ernst-Detlef; Küsel, Kirsten

2012-02-01

331

Luteibacter jiangsuensis sp. nov.: a methamidophos-degrading bacterium isolated from a methamidophos-manufacturing factory.  

PubMed

A Gram-stain-negative, non-motile, rod-shaped bacterial strain, JW-64-1(T), capable of degrading methamidophos was isolated from a methamidophos-manufacturing factory in China, and was subjected to a polyphasic taxonomic investigation. Strain JW-64-1(T) produced circular, smooth, transparent, yellow-colored colonies (1.0-2.0 mm) on LB agar after 2 days incubation. It grew optimally at 25-30°C and pH 7.0 without the presence of NaCl. The G+C content of the total DNA was 63.6 mol%. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain JW-64-1(T) fell within the cluster comprising Luteibacter species. The 16S rRNA gene sequence of strain JW-64-1(T) was most closely related to Luteibacter rhizovicinus DSM 16549(T) (98.6%), followed by Luteibacter yeojuensis DSM 17673(T) (98.4%) and L. anthropi CCUG 25036(T) (98.2%). The major cellular fatty acids of strain JW-64-1(T) were iso-C(15:0) (24.1%), iso-C(17:0) (20.2%) and summed feature 9 comprising iso-C(17:1) ?9c and/or C(16:0) 10-methyl (20.3%). The major isoprenoid quinine was Q-8 (98%), and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphoaminolipid, aminolipids-1, aminolipids-2, and phospholipids. The values for DNA-DNA relatedness between strain JW-64-1(T) and the closest phylogenetic relatives of L. rhizovicinus and Luteibacter yeojuensis were 34.8 ± 2.6 and 25.6 ± 3.1%, respectively. On the basis of the phenotypic, chemotaxonomic, DNA-DNA relatedness and phylogenetic analysis based on the 16S rRNA gene sequences, strain JW-64-1(T) represents a novel species of the genus Luteibacter, for which the name Luteibacter jiangsuensis sp. nov. is proposed. The type strain is JW-64-1(T) (=CGMCC 1.10133(T) = DSM 22396(T)). PMID:20628745

Wang, Li; Wang, Guang-li; Li, Shun-peng; Jiang, Jian-dong

2011-01-01

332

Idiomarina planktonica sp. nov., isolated from a saline lake.  

PubMed

A Gram-stain-negative bacterium, strain TS-T11(T), was isolated from Tuosu lake, a saline lake (salinity 5.4?%, w/v) in the Qaidam basin, Qinghai province, China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain TS-T11(T) were non-spore-forming rods, 0.6-0.8 µm wide and 0.8-2.2 µm long, and motile by means of a single polar flagellum. Strain TS-T11(T) was strictly heterotrophic and aerobic. Cells were positive for catalase and oxidase. Growth was observed in the presence of 0.5-11.0?% (w/v) NaCl (optimum 4.0-6.0?%), at 4-40 °C (optimum 30-35 °C) and at pH 6.0-10.5 (optimum pH 7.5-8.5). Strain TS-T11(T) contained iso-C15?:?0, iso-C17?:?0 and iso-C17?:?1?9c as the predominant fatty acids (>10?%). The major respiratory quinone was Q-8. The polar lipids consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and nine uncharacterized phospholipids. The G+C content of genomic DNA was 46.8 mol% (Tm). Phylogenetic trees based on 16S rRNA gene sequences showed that strain TS-T11(T) was associated with the genus Idiomarina, and showed highest 16S rRNA gene sequence similarity to Idiomarina aestuarii KYW314(T) (97.4?%) and Idiomarina salinarum ISL-52(T) (97.4?%). DNA-DNA relatedness of strain TS-T11(T) to I. aestuarii JCM 16344(T) and I. salinarum DSM 21900(T) was 22.2±2.4 and 11.5±1.6?%, respectively. Based on the data presented above, it was concluded that strain TS-T11(T) represents a novel species of the genus Idiomarina, for which the name Idiomarina planktonica sp. nov. is proposed. The type strain is TS-T11(T) (?=?CGMCC 1.12458(T)?=?JCM 19263(T)). PMID:25015677

Zhong, Zhi-Ping; Liu, Ying; Liu, Hong-Can; Wang, Fang; Song, Lei; Liu, Zhi-Pei

2014-10-01

333

Bacillus xiamenensis sp. nov., isolated from intestinal tract contents of a flathead mullet (Mugil cephalus).  

PubMed

A taxonomic study was carried out on strain HYC-10(T), which was isolated from the intestinal tract contents of a flathead mullet, Mugil cephalus, captured from the sea off Xiamen Island, China. The bacterium was observed to be Gram positive, oxidase and catalase positive, rod shaped, and motile by subpolar flagella. The bacterium was found to grow at salinities of 0-12 % and at temperatures of 8-45 °C. The isolate was found to hydrolyze aesculin and gelatin, but was unable to reduce nitrate to nitrite. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HYC-10(T) belongs to the genus Bacillus, with highest sequence similarity (99.3 %) to Bacillus aerophilus 28K(T), Bacillus stratosphericus 41KF2a(T) and Bacillus altitudinis DSM 21631(T), followed by Bacillus safensis DSM 19292(T) (99.5 %) and Bacillus pumilus DSM 27(T) (99.5 %), while the sequence similarities to others were all below 97.6 %. The genomic ANIm values between strain HYC-10(T) and three type strains (B. altitudinis DSM 21631(T), B. safensis DSM 19292(T) and B. pumilus DSM 27(T)) were determined to range from 89.11 to 91.53 %. The DNA-DNA hybridization estimate values between strain HYC-10(T) and the three type strains were from 36.60 to 44.00 %. The principal fatty acids identified were iso-C15:0 (39.1 %), anteiso-C15:0 (22.7 %), iso-C17:0 (13.1 %), C16:0 (6.1 %), anteiso-C17:0 (5.8 %) and iso-C16:0 (5.1 %). The G+C content of the chromosomal DNA was determined from the draft genome sequence to be 41.3 mol%. The respiratory quinone was determined to be MK-7 (100 %). Phosphatidylglycerol, diphosphatidylglycerol, aminoglycolipid, two glycolipids and two unknown phospholipids were found to be present. The combined genotypic and phenotypic data show that strain HYC-10(T) represents a novel species of the genus Bacillus, for which the name Bacillus xiamenensis sp. nov. is proposed, with the type strain HYC-10(T) (=CGMCC NO.1.12326(T) = LMG 27143(T) = MCCC 1A00008(T)). PMID:24158533

Lai, Qiliang; Liu, Yang; Shao, Zongze

2014-01-01

334

Halomonas zhaodongensis sp. nov., a slightly halophilic bacterium isolated from saline-alkaline soils in Zhaodong, China.  

PubMed

A slightly halophilic bacterium (strain NEAU-ST10-25(T)) was isolated from saline-alkaline soils in Zhaodong City, Heilongjiang Province, China. The strain is a Gram-negative, aerobic motile rod. It accumulates poly-?-hydroxyalkanoate and produces exopolysaccharide. It produces beige-yellow colonies. Growth occurs at NaCl concentrations (w/v) of 0-15 % (optimum 3 %), at temperatures of 4-60 °C (optimum 35 °C) and at pH 6-12 (optimum pH 9). Its G+C content is 53.8 mol%. Phylogenetic analyses based on the separate 16S rRNA gene and concatenation of the 16S rRNA, gyrB and rpoD genes indicate that it belongs to the genus Halomonas in the class Gammaproteobacteria. The most phylogenetically related species is Halomonas alkaliphila DSM 16354(T), with which strain NEAU-ST10-25(T) showed 16S rRNA, gyrB and rpoD gene sequence similarities of 99.2, 82.3 and 88.2 %, respectively. The results of DNA-DNA hybridization assays showed 60.47 ± 0.69 % DNA relatedness between strain NEAU-ST10-25(T) and H. alkaliphila DSM 16354(T), 42.43 ± 0.37 % between strain NEAU-ST10-25(T) and Halomonas venusta DSM 4743(T) and 30.62 ± 0.43 % between strain NEAU-ST10-25(T) and Halomonas hydrothermalis DSM 15725(T). The major fatty acids are C18:1 ?7c (62.3 %), C16:0 (17.6 %), C16:1 ?7c/C16:1 ?6c (7.7 %), C14:0 (2.9 %), C12:0 3-OH (2.8 %), C10:0 (2.1 %) and C18:1 ?9c (1.6 %) and the predominant respiratory quinone is ubiquinone 9 (Q-9). The proposed name is Halomonas zhaodongensis, NEAU-ST10-25(T) (=CGMCC 1.12286(T) = DSM 25869(T)) being the type strain. PMID:23877893

Jiang, Juquan; Pan, Yuanyuan; Meng, Lin; Hu, Shaoxin; Zhang, Xiaoxia; Hu, Baozhong; Meng, Jing; Li, Cheng; Huang, Haipeng; Wang, Kaibiao; Su, Tingting

2013-11-01

335

Pseudoxanthomonas jiangsuensis sp. nov., a DDT-degrading bacterium isolated from a long-term DDT-polluted soil.  

PubMed

A Gram-negative, strictly aerobic, rod-shaped bacterium, designated strain wax(T), was isolated from DDT-contaminated soil in Yangzhou, China. Growth of strain wax(T) was observed at 10-45°C (optimum 30°C) and pH 5.0-10.0 (optimum pH 7.0-8.0). The predominant fatty acids were iso C(15:0) (32.21%) and anteiso C(15:0) (22.2%). The strain contained large amounts of the polar lipids diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol, but small amounts of an unknown amino-group-containing polar lipid and phospholipids were also present. The major quinone was ubiquinone-8 (Q-8) and the G + C content of the genomic DNA was 67.12 ± 0.8 mol.%. The phylogenetic tree shows that strain wax(T) clustered within the genus Pseudoxanthomonas. Isolate wax(T) showed moderate 16S rRNA gene sequence similarities to Pseudoxanthomonas broegbernensis B1616/1(T) (98.3%), P. suwonensis 4M1(T) (98.2%), P. daejeonensis TR6-08(T) (98%), P. koreensis TR7-09(T) (97.7%), P. kaohsiungensis J36(T) (97.5%), P. mexicana AMX 26B(T) (97.2%), and P. japonensis 12-3(T) (97%). The level of DNA-DNA relatedness between strain wax(T) and Pseudoxanthomonas type strains were low, e.g., P. koreensis TR7-09(T) (25.9%), P. broegbernensis B1616/1(T) (36.4%), P. suwonensis 4M1(T) (27.7%), P. daejeonensis TR6-08(T) (40%), P. kaohsiungensis J36(T) (20.4%), P. mexicana AMX 26B(T) (29.0%), P. japonensis 12-3(T) (33.3%). On the basis of the phenotypic, chemotaxonomic data and molecular properties, strain wax(T) represents a novel species within the genus Pseudoxanthomonas, for which the name Pseudoxanthomonas jiangsuensis sp. nov. is proposed. The type strain is wax(T) (=DSM 22398(T) = CGMCC 1.10137(T)). PMID:21445548

Wang, Guang-li; Bi, Meng; Liang, Bin; Jiang, Jian-dong; Li, Shun-peng

2011-06-01

336

Pseudopedobacter beijingensis gen. nov., sp. nov., isolated from coking wastewater activated sludge, and reclassification of Pedobacter saltans as Pseudopedobacter saltans comb. nov.  

PubMed

A taxonomic study was carried out on strain GCS-AE-31(T), which was isolated from a phenol-degrading consortium, enriched from coking wastewater activated sludge of the Beijing Shougang Company Limited during the screening of phenol-degrading bacteria. Cells of strain GCS-AE-31(T) were Gram-stain-negative, short rods, motile by gliding, oxidase- and catalase-positive. Growth was observed at salinities of 0-3% and at temperatures of 10-37 °C. On the basis of 16S rRNA gene sequence similarity, strain GCS-AE-31(T) was most closely related to Pedobacter saltans LMG 10337(T) (96.17%), but it showed low similarity to all other species of the genus Pedobacter (89.28-92.45%). It also showed low 16S rRNA gene similarity to all other species of the family Sphingobacteriaceae (87.25-92.45%) examined. The dominant fatty acids were iso-C(15?:?0), summed feature 3 (C(16?:?1)?7c/C(16?:?1)?6c), anteiso-C(15?:?0) and iso-C(17?:?0) 3-OH. The menaquinones were MK-7 (95.5%) and MK-6 (4.5%). The polar lipids were phosphatidylethanolamine, three aminolipids and three unknown phospholipids. Sphingolipid was present. The G+C content of the chromosomal DNA was 36.2 mol%. According to its phylogenetic position and phenotypic traits, the novel strain could not be assigned to the genus Pedobacter; it should be classified as representing a novel species of a novel genus in the family Sphingobacteriaceae, for which the name Pseudopedobacter beijingensis gen. nov., sp. nov. is proposed (type strain GCS-AE-31(T)?=?MCCC 1A01299(T)?=?CGMCC 1.12329(T)?=?LMG 27180(T)). The misclassified species Pedobacter saltans is transferred to the novel genus as Pseudopedobacter saltans comb. nov. (type strain LMG 10337(T)?=?MCCC 1A06472(T)?=?DSM 12145(T)?=?CCUG 39354(T)?=?CIP 105500(T)?=?JCM 21818(T)?=?NBRC 100064(T)). PMID:24573160

Cao, Junwei; Lai, Qiliang; Li, Guizhen; Shao, Zongze

2014-06-01

337

Muricauda antarctica sp. nov., a marine member of the Flavobacteriaceae isolated from Antarctic seawater.  

PubMed

A Gram-stain-negative, rod-shaped bacterium with appendages, designated Ar-22(T), was isolated from a seawater sample collected from the western part of Prydz Bay, near Cape Darnley, Antarctica. Strain Ar-22(T) grew optimally at 35 °C, at pH 7.5 and in the presence of 1-3% (w/v) NaCl. The isolate was positive for casein, gelatin and Tween 20 decomposition and negative for H2S production and indole formation. Chemotaxonomic analysis showed that MK-6 was the major isoprenoid quinone and phosphatidylethanolamine was the major polar lipid. The major fatty acids were iso-C(17:0) 3-OH, iso-C(15:1) G, iso-C(15:0) and C(16:1)?7c/iso-C(15:0) 2OH. The genomic DNA G+C content was 44.8 mol%. Comparative 16S rRNA gene sequence analysis revealed that strain Ar-22(T) is closely related to members of the genus Muricauda, sharing 94.2-97.3% sequence similarity with the type strains of species of the genus Muricauda and being most closely related to the Muricauda aquimarina. Phylogenetic analysis based on the 16S rRNA gene sequence comparison confirmed that strain Ar-22(T) formed a deep lineage with Muricauda flavescens. Sequence similarity between strain Ar-22(T) and Muricauda ruestringensis DSM 13258(T), the type species of the genus Muricauda, was 96.9%. Strain Ar-22(T) exhibited mean DNA-DNA relatedness values of 40.1%, 49.4% and 25.7% to M. aquimarina JCM 11811(T), M. flavescens JCM 11812(T) and Muricauda lutimaris KCTC 22173(T), respectively. On the basis of phenotypic and genotypic data, strain Ar-22(T) represents a novel species of the genus Muricauda, for which the name Muricauda antarctica sp. nov. (type strain Ar-22(T)?=CGMCC 1.12174(T)?=?JCM 18450(T)) is proposed. PMID:23543499

Wu, Yue-Hong; Yu, Pei-Song; Zhou, Ya-Dong; Xu, Lin; Wang, Chun-Sheng; Wu, Min; Oren, Aharon; Xu, Xue-Wei

2013-09-01

338

Glaciihabitans tibetensis gen. nov., sp. nov., a psychrotolerant bacterium of the family Microbacteriaceae, isolated from glacier ice water.  

PubMed

A Gram-stain-positive, aerobic, non-spore-forming, short-rod-shaped bacterium, designated strain MP203(T), was isolated from ice water of Midui Glacier in Tibet Autonomous Region, China. The strain was psychrotolerant, growing at 0-25 °C. 16S rRNA gene sequence analysis showed that strain MP203(T) was most similar to Frigoribacterium faeni NBRC 103066(T), Compostimonas suwonensis KACC 13354(T), Frigoribacterium mesophilum KCTC 19311(T), Marisediminicola antarctica CCTCC AB 209077(T) and Alpinimonas psychrophila JCM 18951(T), with similarities of 97.4, 97.2, 97.2, 97.1 and 97.1%, respectively. The maximum-likelihood phylogenetic tree indicated that strain MP203(T) clustered with nine genera of the family Microbacteriaceae, namely Frigoribacterium, Compostimonas, Marisediminicola, Alpinimonas, Frondihabitans, Clavibacter, Subtercola, Klugiella and Agreia. However, bootstrap analysis showed that there was no significance in the branching pattern of the linage comprising strain MP203(T) and any existing generic lineage of the family Microbacteriaceae. DNA-DNA hybridization results indicated levels of relatedness between strain MP203(T) and Marisediminicola antarctica CCTCC AB 209077(T), Frigoribacterium faeni NBRC 103066(T), Frigoribacterium mesophilum KCTC 19311(T), Compostimonas suwonensis KACC 13354(T) and Alpinimonas psychrophila JCM 18951(T) were 25.8 ± 7.3, 29.6 ± 7.6, 19.7 ± 6.7, 16.0 ± 4.2 and 12.4 ± 5.1 % (mean ± SD), respectively. The G+C content of the genomic DNA was 64.1 mol%. Analysis of the cell-wall peptidoglycan revealed that the peptidoglycan structure of strain MP203(T) was B10 type with Gly[l-Hse]-D-Glu-D-DAB, containing 2, 4-diaminobutyric acid (DAB) as a diagnostic amino acid. The cell-wall sugars were rhamnose, ribose, mannose and glucose. The major fatty acids were anteiso-C(15 : 0), iso-C(16 : 0) and anteiso A-C(15 : 1). An unusual compound identified as anteiso-C(15 : 0)-DMA (1,1-dimethoxy-anteiso-pentadecane) was also present in strain MP203(T). The predominant menaquinone was MK-10. Diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), one unknown glycolipid and four unknown lipids were detected in the polar lipid extracts. As strain MP203(T) was distinguishable from phylogenetically related genera in the family Microbacteriaceae in terms of its physiological and chemotaxonomic characteristics and phylogenetic position, it was considered to represent a novel species of a new genus. Thus, the name Glaciihabitans tibetensis gen. nov., sp. nov. is proposed. The type strain of Glaciihabitans tibetensis is MP203(T) (?=?CGMCC 1.12484(T)?=?KCTC 29148(T)). PMID:24158943

Li, Ai-Hua; Liu, Hong-Can; Xin, Yu-Hua; Kim, Song-Gun; Zhou, Yu-Guang

2014-02-01

339

Rheinheimera tuosuensis sp. nov., isolated from a saline lake.  

PubMed

A Gram-staining-negative bacterium, strain TS-T4(T), was isolated from Tuosu Lake, a saline lake (salinity 5.4?%, w/w) in Qaidam basin, Qinghai, China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain TS-T4(T) were non-spore-forming rods, 0.4-0.8 µm wide and 1.7-2.3 µm long, and motile by means of a single polar flagellum. Strain TS-T4(T) was strictly heterotrophic, aerobic and catalase- and oxidase-positive. Growth was observed in the presence of 0-7.0?% (w/v) NaCl (optimum, 3.0-4.0?%) and at 4-40 °C (optimum, 30-35 °C) and pH 7.0-10.5 (optimum, pH 8.5-9.0). Strain TS-T4(T) contained Q-8 as the sole respiratory quinone and phosphatidylethanolamine and phosphatidylglycerol as the major polar lipids, as for other members of the genus Rheinheimera. The predominant fatty acids (>10?%) were summed feature 3 (C16?:?1?7c and/or C16?:?1?6c), C16?:?0, C17?:?1?8c and C18?:?1?7c. The DNA G+C content was 50.2 mol% (Tm). Phylogenetic trees based on sequences of the 16S rRNA gene and a conserved portion of the gyrase B gene (gyrB) showed that strain TS-T4(T) was associated with the genus Rheinheimera; the strain showed the highest 16S rRNA gene sequence similarity to Rheinheimera longhuensis LH2-2(T) (97.1?%) and then to Rheinheimera pacifica KMM 1406(T) (97.0?%). DNA-DNA relatedness of strain TS-T4(T) with R. longhuensis LH2-2(T) and R. pacifica NBRC 103167 was 53±2.5 and 48±2?%, respectively. Based on the data presented, it is concluded that TS-T4(T) represents a novel species of the genus Rheinheimera, for which the name Rheinheimera tuosuensis sp. nov. is proposed. The type strain is TS-T4(T) (?=?CGMCC 1.12461(T)?=?JCM 19264(T)). PMID:24408524

Zhong, Zhi-Ping; Liu, Ying; Liu, Liang-Zi; Wang, Fang; Zhou, Yu-Guang; Liu, Zhi-Pei

2014-04-01

340

Aequorivita viscosa sp. nov., isolated from an intertidal zone, and emended descriptions of Aequorivita antarctica and Aequorivita capsosiphonis.  

PubMed

An aerobic, Gram-stain-negative, short rod-shaped, non-motile and non-sporulating bacterium, designed strain 8-1b(T), was isolated from seaweed collected from the intertidal zone of Zhoushan sea area, East China Sea. Strain 8-1b(T) grew at 4-39 °C (optimum, 28-32 °C) and at pH 6.0-9.5 (optimum, 7.0-8.5), and with 0.5-8% (w/v) NaCl (optimum, 1-3%) and 0.5-10% (w/v) sea salts (optimum, 2-3%). Analysis of 16S rRNA gene sequences revealed that strain 8-1b(T) was related closely to Aequorivita capsosiphonis JCM 15070(T) (96.7% similarity). The DNA G+C content of strain 8-1b(T) was 36.6 mol%. Compared with reference strains, cells of strain 8-1b(T) showed positive activities for H?S production and utilization of D-mannose, DL-lactic acid, L-asparagine and glycyl L-aspartic acid. The major fatty acids of strain 8-1b(T) were iso-C(15:0), iso-C(17:0) 3-OH, iso-C(15:1) G and iso-C(17:1)?9c. The main respiratory quinone was menaquinone 6. The polar lipids of strain 8-1b(T) consisted of phosphatidylethanolamine (PE), three uncharacterized aminolipids (AL1-3), four uncharacterized glycolipids (GL1-4) and five uncharacterized lipids (L1-5). Based on the phenotypic and genotypic characterization, strain 8-1b(T) represents a novel species of the genus Aequorivita, for which the name Aequorivita viscosa sp. nov. is proposed. The type strain is strain 8-1b(T) (?=CGMCC 1.11023(T)?=?JCM 18497(T)). Emended descriptions of Aequorivita antarctica and Aequorivita capsosiphonis are also presented. PMID:23435250

Liu, Jin-Jin; Zhang, Xin-Qi; Pan, Jie; Sun, Cong; Zhang, Yong; Li, Chun-Qi; Zhu, Xu-Fen; Wu, Min

2013-09-01

341

Lactivibrio alcoholicus gen. nov., sp. nov., an anaerobic, mesophilic, lactate-, alcohol-, carbohydrate- and amino-acid-degrading bacterium in the phylum Synergistetes.  

PubMed

A mesophilic, obligately anaerobic, lactate-, alcohol-, carbohydrate- and amino-acid- degrading bacterium, designated strain 7WAY-8-7(T), was isolated from an upflow anaerobic sludge blanket reactor treating high-strength organic wastewater from isomerized sugar production processes. Cells of strain 7WAY-8-7(T) were motile, curved rods (0.7-1.0×5.0-8.0 µm). Spore formation was not observed. The strain grew optimally at 37 °C (range for growth was 25-40 °C) and pH 7.0 (pH 6.0-7.5), and could grow fermentatively on yeast extract, glucose, ribose, xylose, malate, tryptone, pyruvate, fumarate, Casamino acids, serine and cysteine. The main end-products of glucose fermentation were acetate and hydrogen. In co-culture with the hydrogenotrophic methanogen Methanospirillum hungatei DSM 864(T), strain 7WAY-8-7(T) could utilize lactate, glycerol, ethanol, 1-propanol, 1-butanol, L-glutamate, alanine, leucine, isoleucine, valine, histidine, asparagine, glutamine, arginine, lysine, threonine, 2-oxoglutarate, aspartate and methionine. A Stickland reaction was not observed with some pairs of amino acids. Yeast extract was required for growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite and Fe (III) were not used as terminal electron acceptors. The G+C content of the genomic DNA was 61.4 mol%. 16S rRNA gene sequence analysis revealed that the isolate belongs to the uncultured environmental clone clade (called 'PD-UASB-13' in the Greengenes database) in the bacterial phylum Synergistetes, showing less than 90% sequence similarity with closely related described species such as Aminivibrio pyruvatiphilus and Aminobacterium colombiense (89.7% and 88.7%, respectively). The major cellular fatty acids were iso-C(13?:?0), iso-C(15?:?0), anteiso-C(15?:?0), C(18?:?1), C(19?:?1), C(20?:?1) and C(21?:?1). A novel genus and species, Lactivibrio alcoholicus gen. nov., sp. nov. is proposed to accommodate strain 7WAY-8-7(T) (?=?JCM 17151(T)?=?DSM 24196(T)?=?CGMCC 1.5159(T)). PMID:24676730

Qiu, Yan-Ling; Hanada, Satoshi; Kamagata, Yoichi; Guo, Rong-Bo; Sekiguchi, Yuji

2014-06-01

342

Desulfobaculum xiamenensis gen. nov., sp. nov., a member of the family Desulfovibrionaceae isolated from marine mangrove sediment.  

PubMed

A taxonomic study was carried out on strain P1(T), which was isolated from mangrove sediment samples collected from Qinglan Port (Hainan, China). Cells were curved rods, that were motile, with a single polar flagellum. The strain was non-spore-forming with a cell size of 0.6×1.5-2.2 µm. Catalase and oxidase activities were not detected. Growth was observed in the temperature range 22-44 °C (optimum, 35-40 °C) and pH range 5.5-8.5 (optimum, pH 7.0). NaCl was required for growth and tolerated at up to 3.5% (w/v) (optimum, 0.5%). Strain P1(T) utilized hydrogen, succinate, L-malate, citrate, oxalate, DL-lactate, pyruvate, or cysteine as electron donors, and sulfate or sulfite as electron acceptors. Fermentation products from pyruvate were acetate, H(2) and CO(2). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain P1(T) formed a distinct evolutionary lineage within the family Desulfovibrionaceae. Strain P1(T) was most closely related to members of the genera Desulfovibrio (92.0-94.3% 16S rRNA gene sequence similarity), Desulfocurvus (91.1%), Bilophila (87.9%) and Lawsonia (86.0%) of the family Desulfovibrionaceae. The DNA G+C content of strain P1(T) was 64.5 mol% and the major cellular fatty acids were iso-C(15:0) (18.8%), anteiso-C(15:0) (5.0%), C(16:0) (14.2%) and iso-C(17:1)?9c (24.4%). The predominant menaquinone was MK-7 (97%). Major polar lipids were phosphatidylcholine, phosphatidylethanolamine and phosphatidylglycerol. Strain P1(T) was distinguishable from members of phylogenetically related genera by differences in several phenotypic properties. On the basis of the phenotypic and phylogenetic data, strain P1(T) represents a novel species of a new genus, for which the name Desulfobaculum xiamenensis gen. nov., sp. nov. is proposed. The type strain of Desulfobaculum xiamenensis is P1(T) (=CGMCC 1.5166(T)=DSM 24233(T)). PMID:21873514

Zhao, Chao; Gao, Zhaoming; Qin, Qiwei; Li, Fuying; Ruan, Lingwei

2012-07-01

343

Manila clams from Hg polluted sediments of Marano and Grado lagoons (Italy) harbor detoxifying Hg resistant bacteria in soft tissues  

SciTech Connect

A mechanism of mercury detoxification has been suggested by a previous study on Hg bioaccumulation in Manila clams (Ruditapes philippinarum) in the polluted Marano and Grado lagoons and in this study we demonstrate that this event could be partly related to the detoxifying activities of Hg-resistant bacteria (MRB) harbored in clam soft tissues. Therefore, natural clams were collected in six stations during two different periods (winter and spring) from Marano and Grado Lagoons. Siphons, gills and hepatopancreas from acclimatized clams were sterile dissected to isolate MRB. These anatomical parts were glass homogenized or used for whole, and they were lying on a solid medium containing 5 mg l{sup ?1} HgCl{sub 2} and incubated at 30 °C. A total of fourteen bacterial strains were isolated and were identified by 16S rDNA sequencing and analysis, revealing that strains were representative of eight bacterial genera, four of which were Gram-positive (Enterococcus, Bacillus, Jeotgalicoccus and Staphylococcus) and other four were Gram-negative (Stenotrophomonas, Vibrio, Raoultella and Enterobacter). Plasmids and merA genes were found and their sequences determined. Fluorescence in situ hybridization (FISH) technique shows the presence of Firmicutes, Actinobacteria and Gammaproteobacteria by using different molecular probes in siphon and gills. Bacterial clumps inside clam flesh were observed and even a Gram-negative endosymbiont was disclosed by transmission electronic microscope inside clam cells. Bacteria harbored in cavities of soft tissue have mercury detoxifying activity. This feature was confirmed by the determination of mercuric reductase in glass-homogenized siphons and gills. -- Highlights: ? We isolated Gram-positive and Gram-negative Hg resistant strains from soft tissues of Ruditapes philippinarum. ? We identify 14 mercury resistant strains by 16S rRNA gene sequences. ? Bacteria in siphon and gill tissues of clams were observed by TEM and identified with different FISH probes. ? Hg-reductase (MerA) activity in glass homogenized clam tissues was also determined.

Baldi, Franco, E-mail: baldi@unive.it [Dipartimento di Scienze Molecolari e Nanosistemi, Cà Foscari University of Venice, Dorsoduro 2137, 30123 Venice (Italy)] [Dipartimento di Scienze Molecolari e Nanosistemi, Cà Foscari University of Venice, Dorsoduro 2137, 30123 Venice (Italy); Gallo, Michele; Marchetto, Davide [Dipartimento di Scienze Molecolari e Nanosistemi, Cà Foscari University of Venice, Dorsoduro 2137, 30123 Venice (Italy)] [Dipartimento di Scienze Molecolari e Nanosistemi, Cà Foscari University of Venice, Dorsoduro 2137, 30123 Venice (Italy); Faleri, Claudia [Department of Environmental Science ‘G. Sarfatti’, University of Siena, 53100 Siena (Italy)] [Department of Environmental Science ‘G. Sarfatti’, University of Siena, 53100 Siena (Italy); Maida, Isabel; Fani, Renato [Dipartimento di Biologia Evoluzionistica, Via Romana, 17, University of Florence, 50125 Florence (Italy)] [Dipartimento di Biologia Evoluzionistica, Via Romana, 17, University of Florence, 50125 Florence (Italy)

2013-08-15

344

[Investigation of the in vitro antibacterial effects of statins].  

PubMed

It was previously shown that statins have anti-inflammatory, immunomodulatory and anti-oxidant effects. This study was aimed to investigate the in-vitro antibacterial effects of simvastatin and atorvastatin. In this study antibacterial activity of the statins were tested against 16 methicillin-susceptible Stophylococcus aureus (MSSA), 16 methicillin-resistant S.aureus (MRSA), 16 methicillin-resistant coagulase-negative Staphylococcus (MRCoNS), 9 vancomycin-susceptible Enterococcus faecium, 7 vancomycin-susceptible Enterococcus faecolis, 13 vancomycin-resistant E. faecium, 16 extended spectrum beta-lactamase (ESBL) positive Escherichia coli, 16 Pseudomonas aeruginosa, 16 Acinetobacter boumannii, 15 ESBL positive Klebsiella pneumoniae, 6 Stenotrophomonas maltophilio by broth microdilution method according to the Clinical and Laboratory Standards Institute (CLSI) performance and interpretive guidelines. S. aureus ATCC 29213, S. aureus ATCC 25923, S. aureus ATCC 43300, Enterococcus faecalis ATCC 29212, K.pneumoniae ATCC 700603 and E. coli ATCC 35218 were tested as control strains. The results showed that minimum inhibitory concentration (MIC) values for all isolates were > 128 microg/ml for the two statins tested. However, MIC of simvastatin was 32 microg/ml for S. aureus ATCC 29213 and was 64 microg/ml for S. aureus ATCC 25923 and E. faecalis ATCC 29212 and was > 128 microg/ml for others, but MIC of atorvastatin was > 128 microg/mI for all standard strains. According to these results, we observed that simvastatin and atorvastain had no significant antibacterial effect in vitro. In this study, although no antibacterial effect of statins were determined in vitro, further studies are needed to investigate the combined effect of statins with antibacterial agents in the living organism. PMID:20455414

Coban, Ahmet Yilmaz; Tekeli, Hacer Ozlem; Güney, Akif Koray; Durupinar, Belma

2010-01-01

345

Huanglongbing, a Systemic Disease, Restructures the Bacterial Community Associated with Citrus Roots?  

PubMed Central

To examine the effect of pathogens on the diversity and structure of plant-associated bacterial communities, we carried out a molecular analysis using citrus and huanglongbing as a host-disease model. 16S rRNA gene clone library analysis of citrus roots revealed shifts in microbial diversity in response to pathogen infection. The clone library of the uninfected root samples has a majority of phylotypes showing similarity to well-known plant growth-promoting bacteria, including Caulobacter, Burkholderia, Lysobacter, Pantoea, Pseudomonas, Stenotrophomonas, Bacillus, and Paenibacillus. Infection by “Candidatus Liberibacter asiaticus” restructured the native microbial community associated with citrus roots and led to the loss of detection of most phylotypes while promoting the growth of bacteria such as Methylobacterium and Sphingobacterium. In pairwise comparisons, the clone library from uninfected roots contained significantly higher 16S rRNA gene diversity, as reflected in the higher Chao 1 richness estimation (P ? 0.01) of 237.13 versus 42.14 for the uninfected and infected clone libraries, respectively. Similarly, the Shannon index of the uninfected clone library (4.46) was significantly higher than that of the infected clone library (2.61). Comparison of the uninfected clone library with the infected clone library using LIBSHUFF statistics showed a significant difference (P ? 0.05). Quantitative PCR analysis revealed that the bacterial community changes not only qualitatively but also quantitatively. The relative proportions of different groups of bacteria changed significantly after infection with the pathogen. These data indicate that infection of citrus by “Ca. Liberibacter asiaticus” has a profound effect on the structure and composition of the bacterial community associated with citrus roots. PMID:20382817

Trivedi, Pankaj; Duan, Yongping; Wang, Nian

2010-01-01

346

Hydrocarbonoclastic bacteria isolated from petroleum contaminated sites in Tunisia: isolation, identification and characterization of the biotechnological potential.  

PubMed

Petroleum hydrocarbons are important energy resources used by industry and in our daily life, whose production contributes highly to environmental pollution. To control such risk, bioremediation constitutes an environmentally friendly alternative technology that has been established and applied. It constitutes the primary mechanism for the elimination of hydrocarbons from contaminated sites by natural existing populations of microorganisms. In this work, a collection of 125 strains, adapted to grow on minimal medium supplemented with crude oil, was obtained from contaminated sediments and seawater from a refinery harbor of the Bizerte coast in the North of Tunisia. The diversity of the bacterial collection was analyzed by amplification of the internal transcribed spacers between the 16S and the 23S rRNA genes (ITS-PCR) and by 16S rRNA sequencing. A total of 36 distinct ITS haplotypes were detected on agarose matrix. Partial 16S rRNA gene sequencing performed on 50 isolates showed high level of identity with known sequences. Strains were affiliated to Ochrabactrum, Sphingobium, Acinetobacter, Gordonia, Microbacterium, Brevundimonas, Novosphingobium, Stenotrophomonas, Luteibacter, Rhodococcus, Agrobacterium, Achromobacter, Bacilllus, Kocuria and Pseudomonas genera. Acinetobacter and Stenotrophomons were found to be the most abundant species characterized by a marked microdiversity as shown through ITS typing. Culture-independent approach (DGGE) showed high diversity in the microbial community in all the studied samples with a clear correlation with the hydrocarbon pollution rate. Sequencing of the DGGE bands revealed a high proportion of Proteobacteria represented by the Alpha and Gamma subclasses. The predominant bacterial detected by both dependent and independent approaches were the Proteobacteria. The biotechnological potential of the isolates revealed a significant production of biosurfactants with important emulsification activities useful in bioremediation. The highest emulsification activity was detected in Pseudomonas geniculata with 52.77% of emulsification. Our overall results suggest that the obtained bacterial isolates may constitute potential candidates for bioremediation and can be useful for biotechnological applications. PMID:23541698

Mahjoubi, Mouna; Jaouani, Atef; Guesmi, Amel; Ben Amor, Sonia; Jouini, Ahlem; Cherif, Hanen; Najjari, Afef; Boudabous, Abdellatif; Koubaa, Nedra; Cherif, Ameur

2013-09-25

347

In Vitro Antibacterial Properties of Pexiganan, an Analog of Magainin  

PubMed Central

Pexiganan, a 22-amino-acid antimicrobial peptide, is an analog of the magainin peptides isolated from the skin of the African clawed frog. Pexiganan exhibited in vitro broad-spectrum antibacterial activity when it was tested against 3,109 clinical isolates of gram-positive and gram-negative, anaerobic and aerobic bacteria. The pexiganan MIC at which 90% of isolates are inhibited (MIC90) was 32 ?g/ml or less for Staphylococcus spp., Streptococcus spp., Enterococcus faecium, Corynebacterium spp., Pseudomonas spp., Acinetobacter spp., Stenotrophomonas spp., certain species of the family Enterobacteriaceae, Bacteroides spp., Peptostreptococcus spp., and Propionibacterium spp. Comparison of the MICs and minimum bactericidal concentrations (MBCs) of pexiganan for 143 isolates representing 32 species demonstrated that for 92% of the isolates tested, MBCs were the same or within 1 twofold difference of the MICs, consistent with a bactericidal mechanism of action. Killing curve analysis showed that pexiganan killed Pseudomonas aeruginosa rapidly, with 106 organisms/ml eliminated within 20 min of treatment with 16 ?g of pexiganan per ml. No evidence of cross-resistance to a number of other antibiotic classes was observed, as determined by the equivalence of the MIC50s and the MIC90s of pexiganan for strains resistant to oxacillin, cefazolin, cefoxitin, imipenem, ofloxacin, ciprofloxacin, gentamicin, and clindamicin versus those for strains susceptible to these antimicrobial agents. Attempts to generate resistance in several bacterial species through repeated passage with subinhibitory concentrations of pexiganan were unsuccessful. In conclusion, pexiganan exhibits properties in vitro which make it an attractive candidate for development as a topical antimicrobial agent. PMID:10103181

Ge, Yigong; MacDonald, Dorothy L.; Holroyd, Kenneth J.; Thornsberry, Clyde; Wexler, Hannah; Zasloff, Michael

1999-01-01

348

Deciphering the Bacterial Microbiome of Citrus Plants in Response to 'Candidatus Liberibacter asiaticus'-Infection and Antibiotic Treatments  

PubMed Central

The bacterial microbiomes of citrus plants were characterized in response to ‘Candidatus Liberibacter asiaticus’ (Las)-infection and treatments with ampicillin (Amp) and gentamicin (Gm) by Phylochip-based metagenomics. The results revealed that 7,407 of over 50,000 known Operational Taxonomic Units (OTUs) in 53 phyla were detected in citrus leaf midribs using the PhyloChip™ G3 array, of which five phyla were dominant, Proteobacteria (38.7%), Firmicutes (29.0%), Actinobacteria (16.1%), Bacteroidetes (6.2%) and Cyanobacteria (2.3%). The OTU62806, representing ‘Candidatus Liberibacter’, was present with a high titer in the plants graft-inoculated with Las-infected scions treated with Gm at 100 mg/L and in the water-treated control (CK1). However, the Las bacterium was not detected in the plants graft-inoculated with Las-infected scions treated with Amp at 1.0 g/L or in plants graft-inoculated with Las-free scions (CK2). The PhyloChip array demonstrated that more OTUs, at a higher abundance, were detected in the Gm-treated plants than in the other treatment and the controls. Pairwise comparisons indicated that 23 OTUs from the Achromobacter spp. and 12 OTUs from the Methylobacterium spp. were more abundant in CK2 and CK1, respectively. Ten abundant OTUs from the Stenotrophomonas spp. were detected only in the Amp-treatment. These results provide new insights into microbial communities that may be associated with the progression of citrus huanglongbing (HLB) and the potential effects of antibiotics on the disease and microbial ecology. PMID:24250784

Zhang, Muqing; Powell, Charles A.; Benyon, Lesley S.; Zhou, Hui; Duan, Yongping

2013-01-01

349

Oil-removal enhancement in media with keratinous or chitinous wastes by hydrocarbon-degrading bacteria isolated from oil-polluted soils.  

PubMed

The aim of this work was to isolate oil-degrading bacteria that use chitin or keratin as carbon sources from oil contaminated soils; and additionally to study if oil removal by these bacteria is enhanced when a chitinous or a keratinous waste is added to the culture media. To isolate the above-mentioned bacteria, 12 soil samples were collected close to an oil-well. Such soils showed unsuitable nutrients content, but their counts of heterotrophic bacteria ranged within 10(5)-10(8) CFU g(-1) soil, of which 0.1-77% corresponded to oil hydrocarbon-degrading ones. By sampling on plates, 109 oil-degrading bacterial isolates were obtained. Their keratinase and chitinase activities were then screened by plate assays and spectrophotometric methods, resulting in 13 isolates that were used to integrate two mixed cultures, one keratinolytic and the other chitinolytic. These mixed cultures were grown in media with oil, or oil supplemented with chicken-feathers or shrimp wastes. The oil-hydrocarbon removal was measured by gas chromatography. Results showed that keratinolytic bacteria were better enzyme producers than the chitinolytic ones, and that oil removal in the presence of chicken-feathers was 3.8 times greater than with shrimp wastes, and almost twice, in comparison with oil-only added cultures. Identification of microorganisms from the mixed cultures by 16S rDNA, indicated the presence of seven different bacterial genera; Stenotrophomonas, Pseudomonas, Brevibacillus, Bacillus, Micrococcus, Lysobacter and Nocardiodes. These findings suggest that the isolated microorganisms and the chicken-feather wastes could be applied to the cleaning of oil-contaminated environments, whether in soil or water. PMID:18613616

Cervantes-González, E; Rojas-Avelizapa, N G; Cruz-Camarillo, R; García-Mena, J; Rojas-Avelizapa, L I

2008-02-01

350

Anaerobic oxidation of arsenite linked to chlorate reduction.  

PubMed

Microorganisms play a significant role in the speciation and mobility of arsenic in the environment. In this study, the oxidation of arsenite [As(III)] to arsenate [As(V)] linked to chlorate (ClO??) reduction was shown to be catalyzed by sludge samples, enrichment cultures (ECs), and pure cultures incubated under anaerobic conditions. No activity was observed in treatments lacking inoculum or with heat-killed sludge, or in controls lacking ClO??. The As(III) oxidation was linked to the complete reduction of ClO?? to Cl?, and the molar ratio of As(V) formed to ClO?? consumed approached the theoretical value of 3:1 assuming the e? equivalents from As(III) were used to completely reduce ClO??. In keeping with O? as a putative intermediate of ClO?? reduction, the ECs could also oxidize As(III) to As(V) with O? at low concentrations. Low levels of organic carbon were essential in heterotrophic ECs but not in autotrophic ECs. 16S rRNA gene clone libraries indicated that the ECs were dominated by clones of Rhodocyclaceae (including Dechloromonas, Azospira, and Azonexus phylotypes) and Stenotrophomonas under autotrophic conditions. Additional phylotypes (Alicycliphilus, Agrobacterium, and Pseudoxanthomonas) were identified in heterotrophic ECs. Two isolated autotrophic pure cultures, Dechloromonas sp. strain ECC1-pb1 and Azospira sp. strain ECC1-pb2, were able to grow by linking the oxidation of As(III) to As(V) with the reduction of ClO??. The presence of the arsenite oxidase subunit A (aroA) gene was demonstrated with PCR in the ECs and pure cultures. This study demonstrates that ClO?? is an alternative electron acceptor to support the microbial oxidation of As(III). PMID:20729322

Sun, Wenjie; Sierra-Alvarez, Reyes; Milner, Lily; Field, Jim A

2010-10-01

351

Phylogenetic diversity of alkaline protease-producing psychrotrophic bacteria from glacier and cold environments of Lahaul and Spiti, India.  

PubMed

The diversity of proteolytic bacteria associated with a glacier and cold environment soils from three different locations in Lahaul and Spiti, India was investigated. Two hundred seventeen bacterial strains were isolated in pure culture. Subsequently these strains were screened for protease-production and one hundred nine showed protease production. From these protease producing psychrotrophic bacteria twenty showing high enzyme production at low temperature and alkaline pH were characterized and identified. The 16S rRNA phylogenetic analysis revealed that none of the strains showed 100% identity with the validly published species of various genera. Isolates belonged to three classes i.e. Actinobacteria, Gammaproteobacteria and Alphaproteobacteria, and were affiliated with the genera Acinetobacter, Arthrobacter, Mycoplana, Pseudomonas, Pseudoxanthomonas, Serratia and Stenotrophomonas. The optimal growth temperature ranged from 10 to 28 degrees C and interestingly, high levels of enzyme productions were measured at growth temperatures between 15 and 25 degrees C, for most of the isolates in plate assay. Most of the isolates were found to produce at least two other hydrolytic enzymes along with protease. The crude protease from one strain was active over broad range of temperature and pH with optima at 30 degrees C and 7.5, respectively. The protease activity was enhanced by Ca(2+), dithiothreitol and beta-mercaptoethanol. While Na(+), Hg(2+), Zn(2+), Mn(2+), phenylmethanesulfonyl fluoride and ethylenediaminetetraacetic acid did not showed much effect on protease activity. The results enrich our knowledge on the psychrotrophic bacterial diversity and biogeographic distribution of enzyme producing bacteria in western Himalaya. PMID:20082368

Salwan, Richa; Gulati, Arvind; Kasana, Ramesh Chand

2010-04-01

352

Thermomonas haemolytica gen. nov., sp. nov., a gamma-proteobacterium from kaolin slurry.  

PubMed

Four aerobic, gram-negative bacterial strains isolated from kaolin slurry used in the production of paper were subjected to a polyphasic analysis and characterization to determine their taxonomic position. Analysis of the 16S rDNA sequences of the four strains revealed that they represent a new lineage within the gamma-Proteobacteria, related to the genera Xanthomonas, Pseudoxanthomonas, Stenotrophomonas, Luteimonas, Xylella and Rhodanobacter. Analysis of the quinone system, the polyamines, the fatty acids and the polar lipids revealed a combination of characteristics that is unique and not described for the phylogenetic relatives. The four strains contain a ubiquinone Q-8, spermidine as the major polyamine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine as the predominant polar lipids, and a fatty acid profile with predominantly iso-branched fatty acids. The G+C content of the genomic DNA was determined to be within the narrow range 67.1-68.7 mol%. Determination of DNA relatedness, as well as riboprint band patterns and amplified fragment length polymorphism profiles, clearly demonstrated that the four strains are members of a single species. Antibiotic-susceptibility patterns were identical for the four strains. Although showing a high degree of similarites in physiological and biochemical patterns, each of the four strains could be distinguished from the others on the basis of a few biochemical characteristics. On the basis of the estimates of phylogenetic relationships derived from the 16S rDNA sequence analyses, the observed chemotaxonomic characteristics and other phenotypic traits, a new genus, Thermomonas gen. nov., and species, Thermomonas haemolytica sp. nov., are proposed for the strains A50-7-3T (= DSM 13605T = LMG 19653T), B 50-7-1 (= DSM 13598 = LMG 19655), D50-7-1 (= DSM 13610 = LMG 19656) and B50-8-1 (= DSM 13599 = LMG 19654), with strain A50-7-3T as the type strain. PMID:11931159

Busse, H J; Kämpfer, P; Moore, E R B; Nuutinen, J; Tsitko, I V; Denner, E B M; Vauterin, L; Valens, M; Rosselló-Mora, R; Salkinoja-Salonen, M S

2002-03-01

353

Anaerobic Oxidation of Arsenite Linked to Chlorate Reduction? †  

PubMed Central

Microorganisms play a significant role in the speciation and mobility of arsenic in the environment. In this study, the oxidation of arsenite [As(III)] to arsenate [As(V)] linked to chlorate (ClO3?) reduction was shown to be catalyzed by sludge samples, enrichment cultures (ECs), and pure cultures incubated under anaerobic conditions. No activity was observed in treatments lacking inoculum or with heat-killed sludge, or in controls lacking ClO3?. The As(III) oxidation was linked to the complete reduction of ClO3? to Cl?, and the molar ratio of As(V) formed to ClO3? consumed approached the theoretical value of 3:1 assuming the e? equivalents from As(III) were used to completely reduce ClO3?. In keeping with O2 as a putative intermediate of ClO3? reduction, the ECs could also oxidize As(III) to As(V) with O2 at low concentrations. Low levels of organic carbon were essential in heterotrophic ECs but not in autotrophic ECs. 16S rRNA gene clone libraries indicated that the ECs were dominated by clones of Rhodocyclaceae (including Dechloromonas, Azospira, and Azonexus phylotypes) and Stenotrophomonas under autotrophic conditions. Additional phylotypes (Alicycliphilus, Agrobacterium, and Pseudoxanthomonas) were identified in heterotrophic ECs. Two isolated autotrophic pure cultures, Dechloromonas sp. strain ECC1-pb1 and Azospira sp. strain ECC1-pb2, were able to grow by linking the oxidation of As(III) to As(V) with the reduction of ClO3?. The presence of the arsenite oxidase subunit A (aroA) gene was demonstrated with PCR in the ECs and pure cultures. This study demonstrates that ClO3? is an alternative electron acceptor to support the microbial oxidation of As(III). PMID:20729322

Sun, Wenjie; Sierra-Alvarez, Reyes; Milner, Lily; Field, Jim A.

2010-01-01

354

Genetic and phenotypic diversity of plant growth promoting rhizobacteria isolated from sugarcane plants growing in pakistan.  

PubMed

Bacteria were isolated from roots of sugarcane varieties grown in the fields of Punjab. They were identified by using API20E/NE bacterial identification kits and from sequences of 16S rRNA and amplicons of the cpn60 gene. The majority of bacteria were found to belong to the genera of Enterobacter, Pseudomonas, and Klebsiella, but members of genera Azospirillum, Rhizobium, Rahnella, Delftia, Caulobacter, Pannonibacter, Xanthomonas, and Stenotrophomonas were also found. The community, however, was dominated by members of the Pseudomonadaceae and Enterobacteriaceae, as representatives of these genera were found in samples from every variety and location examined. All isolates were tested for the presence of five enzymes and seven factors known to be associated with plant growth promotion. Ten isolates showed lipase activity and eight were positive for protease activity. Cellulase, chitinase, and pectinase were not detected in any strain. Nine strains showed nitrogen fixing ability (acetylene reduction assay) and 26 were capable of solubilizing phosphate. In the presence of 100 mg/l tryptophan, all strains except one produced indole acetic acid in the growth medium. All isolates were positive for ACC deaminase activity. Six strains produced homoserine lactones and three produced HCN and hexamate type siderophores. One isolate was capable of inhibiting the growth of 24 pathogenic fungal strains of Colletotrichum, Fusarium, Pythium, and Rhizoctonia spp. In tests of their abilities to grow under a range of temperature, pH, and NaCl concentrations, all isolates grew well on plates with 3% NaCl and most of them grew well at 4 to 41degrees C and at pH 11. PMID:21193815

Mehnaz, Samina; Baig, Deeba Noreen; Lazarovits, George

2010-12-01

355

Cultivable bacterial diversity of alkaline Lonar lake, India.  

PubMed

Aerobic, alkaliphilic bacteria were isolated and characterized from water and sediment samples collected in the winter season, January 2002 from alkaline Lonar lake, India, having pH 10.5. The total number of microorganisms in the sediment and water samples was found to be 10(2)-10(6) cfu g(-1) and 10(2)-10(4) cfu ml(-1), respectively. One hundred and ninety-six strains were isolated using different enrichment media. To study the bacterial diversity of Lonar lake and to select the bacterial strains for further characterization, screening was done on the basis of pH and salt tolerance of the isolates. Sixty-four isolates were subjected to phenotypic, biochemical characterization and 16S rRNA sequencing. Out of 64, 31 bacterial isolates were selected on the basis of their enzyme profile and further subjected to phylogenetic analysis. Phylogenetic analysis indicated that most of the Lonar lake isolates were related to the phylum Firmicutes, containing Low G+C, Gram-positive bacteria, with different genera: Bacillus, Paenibacillus, Alkalibacillus, Exiguobacterium, Planococcus, Enterococcus and Vagococcus. Seven strains constituted a Gram-negative bacterial group, with different genera: Halomonas, Stenotrophomonas and Providencia affiliated to gamma-Proteobacteria, Alcaligenes to beta-Proteobacteria and Paracoccus to alpha-Proteobacteria. Only five isolates were High G+C, Gram-positive bacteria associated with phylum Actinobacteria, with various genera: Cellulosimicrobium, Dietzia, Arthrobacter and Micrococcus. Despite the alkaline pH of the Lonar lake, most of the strains were alkalitolerant and only two strains were obligate alkaliphilic. Most of the isolates produced biotechnologically important enzymes at alkaline pH, while only two isolates (ARI 351 and ARI 341) showed the presence of polyhydroxyalkcanoate (PHA) and exopolysaccharide (EPS), respectively. PMID:17604989

Joshi, Amarja A; Kanekar, Pradnya P; Kelkar, Anita S; Shouche, Yogesh S; Vani, Aijaz A; Borgave, Suchitra B; Sarnaik, Seema S

2008-02-01

356

16S rRNA gene phylogeny and tfdA gene analysis of 2,4-D-degrading bacteria isolated in China.  

PubMed

Twenty-two 2,4-dichlorophenoxyacetic acid (2,4-D)-degrading bacterial isolates were collected from agricultural soils at three sites in China. Sequence analysis of the 16S rRNA genes indicated that the isolates were phylogenetically grouped into four categories: Ochrobactrum anthropi, in the Alpha- class of the phylum Proteobacteria (3 out of 22 isolates), Cupriavidus sp., of the Betaproteobacteria (3 out of 22), Pseudomonas sp. and Stenotrophomonas sp., which are Gammaproteobacteria (7 out of 22), and Bacillus sp., of the phylum Firmicutes (9 out of 22). Primers were designed to amplify the conserved domain of tfdA, which is known to be involved in the degradation of 2,4-D. Results showed that the tfdA genes of all 22 strains were most similar to that of Cupriavidus necator JMP134, which belongs to the 2,4-D/?-ketoglutarate dioxygenase TfdA protein family, indicating that the JMP134-type tfdA gene is likely to be almost universal among the 2,4-D-degrading bacteria isolated from China. Degradation abilities of these 22 strains were investigated in assays using 2,4-D as the sole source of carbon and energy. Thirteen strains degraded >60 % of the available 2,4-D (500 mg l(-1)) over a 1-week incubation period, while a further nine Bacillus sp. strains degraded 50-81 % of the available 2,4-D. None of these nine strains degraded other selected herbicides, such as mecoprop, 2-methyl-4-chlorophenoxyacetic acid, quizalofop, and fluroxypyr. This is the first report of 2,4-D-degradation by Bacilli. PMID:24898178

Han, Lizhen; Liu, Yanbo; He, Aigong; Zhao, Degang

2014-10-01

357

Survey of bacterial diversity in chronic wounds using Pyrosequencing, DGGE, and full ribosome shotgun sequencing  

PubMed Central

Background Chronic wound pathogenic biofilms are host-pathogen environments that colonize and exist as a cohabitation of many bacterial species. These bacterial populations cooperate to promote their own survival and the chronic nature of the infection. Few studies have performed extensive surveys of the bacterial populations that occur within different types of chronic wound biofilms. The use of 3 separate16S-based molecular amplifications followed by pyrosequencing, shotgun Sanger sequencing, and denaturing gradient gel electrophoresis were utilized to survey the major populations of bacteria that occur in the pathogenic biofilms of three types of chronic wound types: diabetic foot ulcers (D), venous leg ulcers (V), and pressure ulcers (P). Results There are specific major populations of bacteria that were evident in the biofilms of all chronic wound types, including Staphylococcus, Pseudomonas, Peptoniphilus, Enterobacter, Stenotrophomonas, Finegoldia, and Serratia spp. Each of the wound types reveals marked differences in bacterial populations, such as pressure ulcers in which 62% of the populations were identified as obligate anaerobes. There were also populations of bacteria that were identified but not recognized as wound pathogens, such as Abiotrophia para-adiacens and Rhodopseudomonas spp. Results of molecular analyses were also compared to those obtained using traditional culture-based diagnostics. Only in one wound type did culture methods correctly identify the primary bacterial population indicating the need for improved diagnostic methods. Conclusion If clinicians can gain a better understanding of the wound's microbiota, it will give them a greater understanding of the wound's ecology and will allow them to better manage healing of the wound improving the prognosis of patients. This research highlights the necessity to begin evaluating, studying, and treating chronic wound pathogenic biofilms as multi-species entities in order to improve the outcomes of patients. This survey will also foster the pioneering and development of new molecular diagnostic tools, which can be used to identify the community compositions of chronic wound pathogenic biofilms and other medical biofilm infections. PMID:18325110

Dowd, Scot E; Sun, Yan; Secor, Patrick R; Rhoads, Daniel D; Wolcott, Benjamin M; James, Garth A; Wolcott, Randall D

2008-01-01

358

Mesophilic and thermophilic biofiltration of gaseous toluene in a long-term operation: performance evaluation, biomass accumulation, mass balance analysis and isolation identification.  

PubMed

A thermophilic biofilter (TBF) was developed to treat high temperature gaseous toluene (55°C). The performance of TBF was evaluated under various operating conditions, including different inlet concentrations and gas flow rates, and compared with a control mesophilic biofilter (MBF). Furthermore, the leachate, biomass accumulation and pressure drop of filter bed were investigated. The experimental results showed that the TBF achieved high performance removal efficiencies of 90% when the inlet loading was lower than 100 gm(-3)h(-1). Increasing inlet loading resulted in lower performance of TBF compared with MBF. However, the biomass in TBF, in the long-term operation, showed a slow accumulation process than MBF. The specific growth rates of microorganism were 0.0011 day(-1) and 0.0015 day(-1) for TBF and MBF, respectively. The slow growth process in TBF further resulted in a lower pressure drop of filter bed (0.1-0.5 kPa) than that of MBF (7-10 kPa). The leachate from TBF presented a neutral pH and presented a higher TOC contents than those from MBF. The results of three-dimensional fluorescence spectra suggested that the products of toluene biodegradation included some organic acids. A carbon mass balance analysis showed that 47.1% of the removed toluene was converted to biomass in MBF, which was higher than that of MBF with 30.5%. Finally, 16s rRNA gene sequences indicated the dominant microorganisms in the TBF including Brevibacillus sp. and Anoxybacillus sp., while Delftia sp. and Stenotrophomonas sp. in the MBF. PMID:22704770

Wang, Can; Kong, Xin; Zhang, Xin-Yue

2012-08-30

359

Could petroleum biodegradation be a joint achievement of aerobic and anaerobic microrganisms in deep sea reservoirs?  

PubMed Central

Several studies suggest that petroleum biodegradation can be achieved by either aerobic or anaerobic microorganisms, depending on oxygen input or other electron acceptors and appropriate nutrients. Evidence from in vitro experiments with samples of petroleum formation water and oils from Pampo Field indicate that petroleum biodegradation is more likely to be a joint achievement of both aerobic and anaerobic bacterial consortium, refining our previous observations of aerobic degradation. The aerobic consortium depleted, in decreasing order, hydrocarbons > hopanes > steranes > tricyclic terpanes while the anaerobic consortium depleted hydrocarbons > steranes > hopanes > tricyclic terpanes. The oxygen content of the mixed consortia was measured from time to time revealing alternating periods of microaerobicity (O2 ~0.8 mg.L-1) and of aerobicity (O2~6.0 mg.L-1). In this experiment, the petroleum biodegradation changed from time to time, alternating periods of biodegradation similar to the aerobic process and periods of biodegradation similar to the anaerobic process. The consortia showed preferences for metabolizing hydrocarbons > hopanes > steranes > tricyclic terpanes during a 90-day period, after which this trend changed and steranes were more biodegraded than hopanes. The analysis of aerobic oil degrading microbiota by the 16S rRNA gene clone library detected the presence of Bacillus, Brevibacterium, Mesorhizobium and Achromobacter, and the analysis of the anaerobic oil degrading microbiota using the same technique detected the presence of Bacillus and Acinetobacter (facultative strains). In the mixed consortia Stenotrophomonas, Brevibacterium, Bacillus, Rhizobium, Achromobacter and 5% uncultured bacteria were detected. This is certainly a new contribution to the study of reservoir biodegradation processes, combining two of the more important accepted hypotheses. PMID:22196374

2011-01-01

360

Ecophysiological properties of cultivable heterotrophic bacteria and yeasts dominating in phytocenoses of Galindez Island, maritime Antarctica.  

PubMed

Antarctic plants are stable specific microenvironments for microbial colonization that are still less explored. In this study, we investigated cultivable heterotrophic bacteria and yeasts dominating in plant samples collected from different terrestrial biotopes near Ukrainian Antarctic Base on Galindez Island, maritime Antarctica. Phylogenetic analysis revealed affiliation of the bacterial isolates to genera Pseudomonas, Stenotrophomonas, Brevundimonas, Sporosarcina, Dermacoccus, Microbacterium, Rothia and Frondihabitans, and the yeast isolates to genera Rhodosporidium, Cryptococcus, Leucosporidiella, Candida and Exophiala. Some ecophysiological properties of isolated strains were determined that are important in response to different stresses such as psychro- and halotolerance, UV-resistance and production of hydrolytic enzymes. The majority of isolates (88 %) was found to be psychrotolerant; all are halotolerant. Significant differences in survival subsequent to UV-C radiation were observed among the isolates, as measured by culturable counts. For the bacterial isolates, lethal doses in the range 80-600 J m?² were determined, and for the yeast isolates--in the range 300-1,000 J m?². Dermacoccus profundi U9 and Candida davisiana U6 were found as most UV resistant among the bacterial and yeast isolates, respectively. Producers of caseinase, gelatinase, ?-glucosidase, and cellulase were detected. To the best of our knowledge, this is the first report on isolation of UV resistant strain D. profundi, and Frondihabitans strain from Antarctica, and on detection of cellulase activity in Antarctic yeast strain C. davisiana. The results obtained contribute to clarifying adaptation strategies of Antarctic microbiota and its possible role in functional stability of Antarctic biocenoses. Stress tolerant strains were detected that are valuable for ecological and applied studies. PMID:24277323

Vasileva-Tonkova, Evgenia; Romanovskaya, Victoria; Gladka, Galina; Gouliamova, Dilnora; Tomova, Iva; Stoilova-Disheva, Margarita; Tashyrev, Oleksandr

2014-04-01

361

Contribution of the Microbial Communities Detected on an Oil Painting on Canvas to Its Biodeterioration  

PubMed Central

In this study, we investigated the microbial community (bacteria and fungi) colonising an oil painting on canvas, which showed visible signs of biodeterioration. A combined strategy, comprising culture-dependent and -independent techniques, was selected. The results derived from the two techniques were disparate. Most of the isolated bacterial strains belonged to related species of the phylum Firmicutes, as Bacillus sp. and Paenisporosarcina sp., whereas the majority of the non-cultivable members of the bacterial community were shown to be related to species of the phylum Proteobacteria, as Stenotrophomonas sp. Fungal communities also showed discrepancies: the isolated fungal strains belonged to different genera of the order Eurotiales, as Penicillium and Eurotium, and the non-cultivable belonged to species of the order Pleosporales and Saccharomycetales. The cultivable microorganisms, which exhibited enzymatic activities related to the deterioration processes, were selected to evaluate their biodeteriorative potential on canvas paintings; namely Arthrobacter sp. as the representative bacterium and Penicillium sp. as the representative fungus. With this aim, a sample taken from the painting studied in this work was examined to determine the stratigraphic sequence of its cross-section. From this information, “mock paintings,” simulating the structure of the original painting, were prepared, inoculated with the selected bacterial and fungal strains, and subsequently examined by micro-Fourier Transform Infrared spectroscopy, in order to determine their potential susceptibility to microbial degradation. The FTIR-spectra revealed that neither Arthrobacter sp. nor Penicillium sp. alone, were able to induce chemical changes on the various materials used to prepare “mock paintings.” Only when inoculated together, could a synergistic effect on the FTIR-spectra be observed, in the form of a variation in band position on the spectrum. PMID:24312203

Lopez-Miras, Maria del Mar; Martin-Sanchez, Ines; Yebra-Rodriguez, Africa; Romero-Noguera, Julio; Bolivar-Galiano, Fernando; Ettenauer, Jorg; Sterflinger, Katja; Pinar, Guadalupe

2013-01-01

362

Reversible oxygen-tolerant hydrogenase carried by free-living N2-fixing bacteria isolated from the rhizospheres of rice, maize, and wheat  

PubMed Central

Hydrogen production by microorganisms is often described as a promising sustainable and clean energy source, but still faces several obstacles, which prevent practical application. Among them, oxygen sensitivity of hydrogenases represents one of the major limitations hampering the biotechnological implementation of photobiological production processes. Here, we describe a hierarchical biodiversity-based approach, including a chemochromic screening of hydrogenase activity of hundreds of bacterial strains collected from several ecosystems, followed by mass spectrometry measurements of hydrogenase activity of a selection of the H2-oxidizing bacterial strains identified during the screen. In all, 131 of 1266 strains, isolated from cereal rhizospheres and basins containing irradiating waste, were scored as H2-oxidizing bacteria, including Pseudomonas sp., Serratia sp., Stenotrophomonas sp., Enterobacter sp., Rahnella sp., Burkholderia sp., and Ralstonia sp. isolates. Four free-living N2-fixing bacteria harbored a high and oxygen-tolerant hydrogenase activity, which was not fully inhibited within entire cells up to 150–250 ?mol/L O2 concentration or within soluble protein extracts up to 25–30 ?mol/L. The only hydrogenase-related genes that we could reveal in these strains were of the hyc type (subunits of formate hydrogenlyase complex). The four free-living N2-fixing bacteria were closely related to Enterobacter radicincitans based on the sequences of four genes (16S rRNA, rpoB, hsp60, and hycE genes). These results should bring interesting prospects for microbial biohydrogen production and might have ecophysiological significance for bacterial adaptation to the oxic–anoxic interfaces in the rhizosphere. PMID:23233392

Roumagnac, Philippe; Richaud, Pierre; Barakat, Mohamed; Ortet, Philippe; Roncato, Marie-Anne; Heulin, Thierry; Peltier, Gilles; Achouak, Wafa; Cournac, Laurent

2012-01-01

363

Hospital Acquired Infections: Preventable Cause of Mortality in Spinal Cord Injury Patients  

PubMed Central

Background: There is an alarming rate of morbidity and mortality observed in the trauma victims who suffer spinal cord injuries (SCI). Such patients are admitted immediately and stay for longer periods of time and thus are at risk of acquiring nosocomial infections. Aims: The aim of this study is to analyze the primary cause of mortality in SCI patients. Design: Retrospective study. Materials and Methods: We conducted a retrospective 4 year analysis of the postmortem data of 341 patients who died after sustaining SCI at a tertiary care apex trauma center of India. Epidemiological data of patients including the type of trauma, duration of hospital stay, cause of death and microbiological data were recorded. Results: On autopsy, out of 341 patients, the main cause of death in the SCI patients was ascertained to be infection/septicemia in 180 (52.7%) patients, the rest 161 (47.2%) died due to severe primary injury. Respiratory tract infections (36.4%) were predominant followed by urinary tract infections (32.2%), blood stream infections (22.2%), wound infections (7.1%) and meningitis reported in only 5 (2.1%) cases. Acinetobacter sp (40%) was the predominant organism isolated, followed by Pseudomonas sp (16.3%), Klebsiella sp (15.1%), Candida sp (7.8%), Escherichia coli (6.9%), Staphylococcus aureus (6.9%), Proteus sp (3.3%), Enterobacter sp and Burkholderia sp (two cases each) and Stenotrophomonas sp (one case). A high level of multidrug resistance was observed. Conclusions: Hospital acquired infections (HAI) are leading cause of loss of young lives in trauma patients; hence efforts should be made to prevent HAIs. PMID:24695997

Lalwani, Sanjeev; Punia, Parul; Mathur, Purva; Trikha, Vivek; Satyarthee, Gurudutta; Misra, Mahesh C

2014-01-01

364

Tertiary structure-related activity of tick defensin (persulcatusin) in the taiga tick, Ixodes persulcatus.  

PubMed

Defensins are small cysteine-rich cationic proteins found in both vertebrates and invertebrates constituting the front line of host innate immunity. To examine the importance of the tertiary structure of tick defensin in its antimicrobial activity, we synthesized two types of the peptides with tertiary structure or primary one on basis of the information of the sequence in the defensin originated from the taiga tick, Ixodes persulcatus. Chemically synthesized peptides were used to investigate the activity spectrum against Staphylococcus aureus, Borrelia garinii and flora-associated bacteria. Both synthetic peptides showed antimicrobial activity against S. aureus in short-time killing within 1 h, but they do not show the activity against B. garinii, Stenotrophomonas maltophila and Bacillus spp., which were frequently isolated from the midgut of I. persulcatus. The teriary structure brought more potent activity to S. aureus than primary one in short-time killing. We also examined its antimicrobial activity by evaluation of growth inhibition in the presence of the synthetic peptides. Minimum inhibitory concentration (MIC) was ranged from 1.2 to 5.0 ?g/ml in tertiary peptide and from 10 to 40 ?g/ml in primary peptide, when 10 strains of S. aureus were used. From the curve of cumulative inhibition rates, MIC50 (MIC which half of the strains showed) to S. aureus is about 1.2 ?g/ml in the peptide with tertiary structure and about 10 ?g/ml in the linear one. Corynebacterium renale is 10 times or more sensitive to tertiary peptide than primary one. In conclusion, the presence of 3 disulfide bridges, which stabilize the molecule and maintain the tertiary structure, is considered to have an effect on their antimicrobial activities against Gram-positive bacteria such as S. aureus. PMID:20596886

Isogai, Emiko; Isogai, Hiroshi; Okumura, Kazuhiko; Hori, Hatsuhiro; Tsuruta, Hiroki; Kurebayashi, Yoichi

2011-01-01

365

Dynamic of functional microbial groups during mesophilic composting of agro-industrial wastes and free-living (N2)-fixing bacteria application.  

PubMed

Although several reports are available concerning the composition and dynamics of the microflora during the composting of municipal solid wastes, little is known about the microbial diversity during the composting of agro-industrial refuse. For this reason, the first parts of this study included the quantification of microbial generic groups and of the main functional groups of C and N cycle during composting of agro-industrial refuse. After a generalized decrease observed during the initial phases, a new bacterial growth was observed in the final phase of the process. Ammonifiers and (N2)-fixing aerobic groups predominated outside of the piles whereas, nitrate-reducing group increased inside the piles during the first 23days of composting. Ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB), showed an opposite trend of growth since ammonia oxidation decreased with the increase of the nitrite oxidation activity. Pectinolytics, amylolytics and aerobic cellulolytic were present in greater quantities and showed an upward trend in both the internal and external part of the heaps. Several free-living (N2)-fixing bacteria were molecularly identify as belonging especially to uncommon genera of nitrogen-fixing bacteria as Stenotrophomonas, Xanthomonas, Pseudomonas, Klebsiella, Alcaligenes, Achromobacter and Caulobacter. They were investigated for their ability to fix atmospheric nitrogen to employ as improvers of quality of compost. Some strains of Azotobacter chrococcum and Azotobacter salinestris were also tested. When different diazotrophic bacterial species were added in compost, the increase of total N ranged from 16% to 27% depending on the selected microbial strain being used. Such microorganisms may be used alone or in mixtures to provide an allocation of plant growth promoting rhizobacteria in soil. PMID:23647951

Pepe, Olimpia; Ventorino, Valeria; Blaiotta, Giuseppe

2013-07-01

366

Molecular and lipid biomarker analysis of a gypsum-hosted endoevaporitic microbial community.  

PubMed

Modern evaporitic microbial ecosystems are important analogs for understanding the record of earliest life on Earth. Although mineral-depositing shallow-marine environments were prevalent during the Precambrian, few such environments are now available today for study. We investigated the molecular and lipid biomarker composition of an endoevaporitic gypsarenite microbial mat community in Guerrero Negro, Mexico. The 16S ribosomal RNA gene-based phylogenetic analyses of this mat corroborate prior observations indicating that characteristic layered microbial communities colonize gypsum deposits world-wide despite considerable textural and morphological variability. Membrane fatty acid analysis of the surface tan/orange and lower green mat crust layers indicated cell densities of 1.6 × 10(9) and 4.2 × 10(9)  cells cm(-3) , respectively. Several biomarker fatty acids, ?7,10-hexadecadienoic, iso-heptadecenoic, 10-methylhexadecanoic, and a ?12-methyloctadecenoic, correlated well with distributions of Euhalothece, Stenotrophomonas, Desulfohalobium, and Rhodobacterales, respectively, revealed by the phylogenetic analyses. Chlorophyll (Chl) a and cyanobacterial phylotypes were present at all depths in the mat. Bacteriochlorophyl (Bchl) a and Bchl c were first detected in the oxic-anoxic transition zone and increased with depth. A series of monomethylalkanes (MMA), 8-methylhexadecane, 8-methylheptadecane, and 9-methyloctadecane were present in the surface crust but increased in abundance in the lower anoxic layers. The MMA structures are similar to those identified previously in cultures of the marine Chloroflexus-like organism 'Candidatus Chlorothrix halophila' gen. nov., sp. nov., and may represent the Bchl c community. Novel 3-methylhopanoids were identified in cultures of marine purple non-sulfur bacteria and serve as a probable biomarker for this group in the lower anoxic purple and olive-black layers. Together microbial culture and environmental analyses support novel sources for lipid biomarkers in gypsum crust mats. PMID:24325308

Jahnke, L L; Turk-Kubo, K A; N Parenteau, M; Green, S J; Kubo, M D Y; Vogel, M; Summons, R E; Des Marais, D J

2014-01-01

367

Dynamics of Soil Bacterial Communities in Response to Repeated Application of Manure Containing Sulfadiazine  

PubMed Central

Large amounts of manure have been applied to arable soils as fertilizer worldwide. Manure is often contaminated with veterinary antibiotics which enter the soil together with antibiotic resistant bacteria. However, little information is available regarding the main responders of bacterial communities in soil affected by repeated inputs of antibiotics via manure. In this study, a microcosm experiment was performed with two concentrations of the antibiotic sulfadiazine (SDZ) which were applied together with manure at three different time points over a period of 133 days. Samples were taken 3 and 60 days after each manure application. The effects of SDZ on soil bacterial communities were explored by barcoded pyrosequencing of 16S rRNA gene fragments amplified from total community DNA. Samples with high concentration of SDZ were analyzed on day 193 only. Repeated inputs of SDZ, especially at a high concentration, caused pronounced changes in bacterial community compositions. By comparison with the initial soil, we could observe an increase of the disturbance and a decrease of the stability of soil bacterial communities as a result of SDZ manure application compared to the manure treatment without SDZ. The number of taxa significantly affected by the presence of SDZ increased with the times of manure application and was highest during the treatment with high SDZ-concentration. Numerous taxa, known to harbor also human pathogens, such as Devosia, Shinella, Stenotrophomonas, Clostridium, Peptostreptococcus, Leifsonia, Gemmatimonas, were enriched in the soil when SDZ was present while the abundance of bacteria which typically contribute to high soil quality belonging to the genera Pseudomonas and Lysobacter, Hydrogenophaga, and Adhaeribacter decreased in response to the repeated application of manure and SDZ. PMID:24671113

Ding, Guo-Chun; Radl, Viviane; Schloter-Hai, Brigitte; Jechalke, Sven; Heuer, Holger; Smalla, Kornelia; Schloter, Michael

2014-01-01

368

Spatial and Species Variations in Bacterial Communities Associated with Corals from the Red Sea as Revealed by Pyrosequencing  

PubMed Central

Microbial associations with corals are common and are most likely symbiotic, although their diversity and relationships with environmental factors and host species remain unclear. In this study, we adopted a 16S rRNA gene tag-pyrosequencing technique to investigate the bacterial communities associated with three stony Scleractinea and two soft Octocorallia corals from three locations in the Red Sea. Our results revealed highly diverse bacterial communities in the Red Sea corals, with more than 600 ribotypes detected and up to 1,000 species estimated from a single coral species. Altogether, 21 bacterial phyla were recovered from the corals, of which Gammaproteobacteria was the most dominant group, and Chloroflexi, Chlamydiae, and the candidate phylum WS3 were reported in corals for the first time. The associated bacterial communities varied greatly with location, where environmental conditions differed significantly. Corals from disturbed areas appeared to share more similar bacterial communities, but larger variations in community structures were observed between different coral species from pristine waters. Ordination methods identified salinity and depth as the most influential parameters affecting the abundance of Vibrio, Pseudoalteromonas, Serratia, Stenotrophomonas, Pseudomonas, and Achromobacter in the corals. On the other hand, bacteria such as Chloracidobacterium and Endozoicomonas were more sensitive to the coral species, suggesting that the host species type may be influential in the associated bacterial community, as well. The combined influences of the coral host and environmental factors on the associated microbial communities are discussed. This study represents the first comparative study using tag-pyrosequencing technology to investigate the bacterial communities in Red Sea corals. PMID:22865078

Lee, On On; Yang, Jiangke; Bougouffa, Salim; Wang, Yong; Batang, Zenon; Tian, Renmao; Al-Suwailem, Abdulaziz

2012-01-01

369

Phylogenetic analyses of the genus Glaciecola: emended description of the genus Glaciecola, transfer of Glaciecola mesophila, G. agarilytica, G. aquimarina, G. arctica, G. chathamensis, G. polaris and G. psychrophila to the genus Paraglaciecola gen. nov. as Paraglaciecola mesophila comb. nov., P. agarilytica comb. nov., P. aquimarina comb. nov., P. arctica comb. nov., P. chathamensis comb. nov., P. polaris comb. nov. and P. psychrophila comb. nov., and description of Paraglaciecola oceanifecundans sp. nov., isolated from the Southern Ocean.  

PubMed

Phylogenetic analyses of the genus Glaciecola were performed using the sequences of the 16S rRNA gene and the GyrB protein to establish its taxonomic status. The results indicated a consistent clustering of the genus Glaciecola into two clades, with significant bootstrap values, with all the phylogenetic methods employed. Clade 1 was represented by seven species, Glaciecola agarilytica, G. aquimarina, G. arctica, G. chathamensis, G. mesophila, G. polaris and G. psychrophila, while clade 2 consisted of only three species, Glaciecola nitratireducens, G. pallidula and G. punicea. Evolutionary distances between species of clades 1 and 2, based on 16S rRNA gene and GyrB protein sequences, ranged from 93.0 to 95.0?% and 69.0 to 73.0?%, respectively. In addition, clades 1 and 2 possessed 18 unique signature nucleotides, at positions 132, 184?:?193, 185?:?192, 230, 616?:?624, 631, 632, 633, 738, 829, 1257, 1265, 1281, 1356 and 1366, in the 16S rRNA gene sequence and can be differentiated by the occurrence of a 15 nt signature motif 5'-CAAATCAGAATGTTG at positions 1354-1368 in members of clade 2. Robust clustering of the genus Glaciecola into two clades based on analysis of 16S rRNA gene and GyrB protein sequences, 16S rRNA gene sequence similarity of ?95.0?% and the occurrence of signature nucleotides and signature motifs in the 16S rRNA gene suggested that the genus should be split into two genera. The genus Paraglaciecola gen. nov. is therefore created to accommodate the seven species of clade 1, while the name Glaciecola sensu stricto is retained to represent species of clade 2. The species of clade 1 are transferred to the genus Paraglaciecola as Paraglaciecola mesophila comb. nov. (type strain DSM 15026(T)?=?KMM 241(T)), P. agarilytica comb. nov. (type strain NO2(T)?=?KCTC 12755(T)?=?LMG 23762(T)), P. aquimarina comb. nov. (type strain GGW-M5(T)?=?KCTC 32108(T)?=?CCUG 62918(T)), P. arctica comb. nov. (type strain BSs20135(T)?=?CCTCC AB 209161(T)?=?KACC 14537(T)), P. chathamensis comb. nov. (type strain E3(T)?=?CGMCC 1.7001(T)?=?JCM 15139(T)), P. polaris comb. nov. (type strain ARK 150(T)?=?CIP 108324(T)?=?LMG 21857(T)) and P. psychrophila comb. nov. (type strain 170(T)?=?CGMCC1.6130(T)?=?JCM 13954(T)). Th