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Sample records for aeromonas strains isolated

  1. Draft Genome Sequence of Aeromonas molluscorum Strain 848TT, Isolated from Bivalve Molluscs.

    PubMed

    Spataro, Nino; Farfán, Maribel; Albarral, Vicenta; Sanglas, Ariadna; Lorén, J Gaspar; Fusté, M Carmen; Bosch, Elena

    2013-06-20

    We report here the draft genome sequence of Aeromonas molluscorum 848T, the type strain of this Aeromonas species, which was isolated from wedge shells (Donax trunculus) obtained from a retail market in Barcelona, Spain, in 1997.

  2. [Phenotypic characteristics and virulence factors in Aeromonas strains isolated from patients with diarrheic disease in Cuba].

    PubMed

    Bravo, Laura; Fernández, Anabel; Ledo, Judith; Ramírez, Margarita; Aguila, Adalberto; Núñez, Fidel A; Cabrera, Luis E; Cruz, Yanaika

    2011-04-01

    Fifty four strains of Aeromonas spp were isolated from patients with acute diarrheic episodes by using Aerokey II and Aeroesquema methods. In vitro antimicrobial susceptibility and virulence factors were analyzed. The most frequently isolated specie was Aeromonas caviae. Over 75% of strains exhibited resistance to penicillins and ce-phalosporins; for the other antibiotic groups resistance was under 20%. Twenty six strains (48.1 %) were multiresist-ant. At least one virulence factor among those evaluated in the study was present in 53 (98.1%) of the 54 strains. PMID:21720696

  3. Draft Genome Sequence of Aeromonas caviae Strain 429865 INP, Isolated from a Mexican Patient

    PubMed Central

    Padilla, Juan Carlos A.; Bustos, Patricia; Sánchez-Varela, Alejandro; Palma-Martinez, Ingrid; Arzate-Barbosa, Patricia; García-Pérez, Carlos A.; López-López, María de Jesús; González, Víctor

    2015-01-01

    Aeromonas caviae is an emerging human pathogen. Here, we report the draft genome sequence of Aeromonas caviae strain 429865 INP which shows the presence of various putative virulence-related genes. PMID:26494682

  4. Aspects of constitutive and acquired antibioresistance in Aeromonas hydrophila strains isolated from water sources.

    PubMed

    Balotescu, Carmen; Israil, Anca; Radu, Roxana; Alexandru, Ionela; Dobre, Georgeta

    2003-01-01

    without a direct medical impact, however they could play an indirect one remaining permanent sources of R genes for bacterial strains with pathogenic abilities implicated in human pathology (i.e. Aeromonas infections in man related to different professional activities such as fishing, surfing, swimming, diving, etc.). The purpose of this work was to determine the aspects related to constitutive and acquired antibioresistance in 35 A. hydrophila strains isolated in aquatic environment of Danube Delta (10 salmaster waters, 5 aquatic plants, 5 fish intestinal content, 5 fish sapling, 5 snake and oyster shells). The strains were biochemically identified by using API20E and API20NE kits. The antibioresistance spectrum was determined by disk diffusion method following NCCLS 2000 recommendations. The choice and disposal of antibiotics on the Mueller Hinton plate was done to allow the interpretive reading and the phenotypic detection of different antibioresistance mechanisms, as follows: beta-lactamases (PEN, ME, AMX, AMC, CAZ) and carbapenemase (IMP) production; porin deficiency (FOX); efflux mechanism (C, TE, NOR). All tested strains exhibited high resistance to penicillin, aspect pleading for constitutive penicillinase production in Aeromonas strains. With reference to other penicillins (ME, AMX, AMC) and cephalosporins (CAZ, FOX) the tested strains exhibited 2 different antibioresistance patterns: AMX-R, AMC-S, CAZ-S (65%) indicating the presence of beta-lactamase sensitive to inhibitors and AMX-R, AMC-R, CAZ-S (22%) indicating the presence of beta-lactamase resistant to inhibitors. Resistance to FOX in 8% of strains signifies a phenotypical marker for the presence of porin deficiency. Only one Aeromonas strain (2.8%) was resistant to IMP. Three strains (8%) were simultaneous resistant to TE and TMP/SMX, NOR and CHL probably due to the presence of a resistance plasmid (codifying an efflux/ enzymatic mechanism). These aspects are pleading for the necessity to investigate the

  5. Quorum sensing activity of Aeromonas caviae strain YL12, a bacterium isolated from compost.

    PubMed

    Lim, Yan-Lue; Ee, Robson; Yin, Wai-Fong; Chan, Kok-Gan

    2014-04-22

    Quorum sensing is a well-studied cell-to-cell communication method that involves a cell-density dependent regulation of genes expression mediated by signalling molecules. In this study, a bacterium isolated from a plant material compost pile was found to possess quorum sensing activity based on bioassay screening. Isolate YL12 was identified using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and molecular typing using rpoD gene which identified the isolate as Aeromonas caviae. High resolution tandem mass spectrometry was subsequently employed to identify the N-acyl homoserine lactone profile of Aeromonas caviae YL12 and confirmed that this isolate produced two short chain N-acyl homoserine lactones, namely C4-HSL and C6, and the production was observed to be cell density-dependent. Using the thin layer chromatography (TLC) bioassay, both AHLs were found to activate C. violaceum CV026, whereas only C6-HSL was revealed to induce bioluminescence expression of E. coli [pSB401]. The data presented in this study will be the leading steps in understanding the role of quorum sensing in Aeromonas caviae strain YL12.

  6. Draft genome sequence of the Chilean isolate Aeromonas salmonicida strain CBA100.

    PubMed

    Valdes, Natalia; Espinoza, Carolina; Sanhueza, Loreto; Gonzalez, Alex; Corsini, Gino; Tello, Mario

    2015-03-01

    We report the draft genome sequence from Aeromonas salmonicida sp. strain CBA100, which was characterized as an antibiotic-resistant bacterium isolated from infected rainbow trout. The total size of the genome is 4,788,109 bp, with a G + C content of 60.55%. Comparison of its open reading frames shows that the closest homologue to one third of the genes of strain CBA100 are found in A. hydrophila. The strain contains several efflux pumps and putative genes that confer resistance to multiclass antibiotics, including macrolide, β-lactamics, florfenicol and quinolones. The antibiogram profile suggests that efflux pumps are the main mechanism of resistance to non-β-lactamic antibiotics. This is the first genome of a Chilean isolate of A. salmonicida, which should shed light on the design of strain-specific vaccines against this pathogen and reduce the use of antibiotics for preventive treatment in Chilean aquaculture.

  7. Potential pathogenicity of Aeromonas hydrophila complex strains isolated from clinical, food, and environmental sources.

    PubMed

    Albarral, Vicenta; Sanglas, Ariadna; Palau, Montserrat; Miñana-Galbis, David; Fusté, M Carmen

    2016-04-01

    Aeromonas are autochthonous inhabitants of aquatic environments, including chlorinated and polluted waters, although they can also be isolated from a wide variety of environmental and clinical sources. They cause infections in vertebrates and invertebrates and are considered to be an emerging pathogen in humans, producing intestinal and extra-intestinal diseases. Most of the clinical isolates correspond to A. hydrophila, A. caviae, and A. veronii bv. Sobria, which are described as the causative agents of wound infections, septicaemia, and meningitis in immunocompromised people, and diarrhoea and dysenteric infections in the elderly and children. The pathogenic factors associated with Aeromonas are multifactorial and involve structural components, siderophores, quorum-sensing mechanisms, secretion systems, extracellular enzymes, and exotoxins. In this study, we analysed a representative number of clinical and environmental strains belonging to the A. hydrophila species complex to evaluate their potential pathogenicity. We thereby detected their enzymatic activities and antibiotic susceptibility pattern and the presence of virulence genes (aer, alt, ast, and ascV). The notably high prevalence of these virulence factors, even in environmental strains, indicated a potential pathogenic capacity. Additionally, we determined the adhesion capacity and cytopathic effects of this group of strains in Caco-2 cells. Most of the strains exhibited adherence and caused complete lysis.

  8. Draft Genome Sequence of Aeromonas caviae Strain L12, a Quorum-Sensing Strain Isolated from a Freshwater Lake in Malaysia.

    PubMed

    Chan, Kok-Gan; Chin, Pui-San; Tee, Kok Keng; Chang, Chien-Yi; Yin, Wai-Fong; Sheng, Kit-Yeng

    2015-03-05

    Here, we present the draft genome sequence of Aeromonas caviae strain L12, which shows quorum-sensing activity. The availability of this genome sequence is important to the research of the quorum-sensing regulatory system in this isolate.

  9. Enterotoxigenicity of aeromonas strains in suckling mice.

    PubMed

    Jánossy, G; Tarján, V

    1980-01-01

    The enterotoxigenicity of 170 Aeromonas strains isolated from different sources (food poisoning, random food sampling, water, faeces) was examined by the suckling mouse test. The strains were grown on Syncaye culture medium covered with sterilized membrane for Kiil-kidney. The culture supernatants were inoculated orally. Ileal loop dilatation was compared to that produced by the international standard enterotoxic Escherichia coli B7A (O148 : H28) and B2C (O6 : H16) strains. Of the 87 Aeromonas hydrophila strains 69, of the 76 Aeromonas punctate subsp. caviae strains 9, the 6 Aeromonas punctata subsp. punctata strains 5, and 1 Aeromonas salmonicida subsp. achromogenes gave a positive reaction in the test.

  10. Characterization of Aeromonas strains isolated from Indian foods using rpoD gene sequencing and whole cell protein analysis.

    PubMed

    Nagar, Vandan; Shashidhar, Ravindranath; Bandekar, Jayant R

    2013-04-01

    Aeromonas are responsible for causing gastroenteritis and extra-intestinal infections in humans. Twenty-two Aeromonas strains isolated from different food sources were re-identified up to species level using rpoD gene sequence analysis. Biochemical tests and 16S rRNA gene sequencing were insufficient to identify Aeromonas till species level. However, incorporation of additional biochemical tests lead to correct identification of 95.5 % strains up to species level. The 16S rRNA gene sequencing was useful to identify Aeromonas isolates at the genus level only. Sequences of the rpoD gene showed greater discriminatory power than 16S rRNA gene and provided conclusive discrimination of the strains for which the phenotypic species identification was uncertain. All these 22 strains were accurately identified up to species level by rpoD gene as A. salmonicida (6), A. veronii bv. veronii (4), A. caviae (3), A. hydrophila (2), A. veronii bv. sobria (2), A. jandaei (1), A. trota (1), A. sobria (1), A. allosaccharophila (1) and A. bivalvium (1). All these strains were also characterized using whole cell protein (WCP) analysis by gradient SDS-PAGE and showed different whole cell protein (WCP) profile [22-28 polypeptide bands (~10 to >97 kDa)], indicating high genetic diversity. The present work emphasizes the use of molecular methods such as rpoD gene sequencing along with comprehensive biochemical tests for the rapid and accurate identification of Aeromonas isolates till species level. The WCP profile can be subsequently used to characterize Aeromonas isolates below species level.

  11. Phenotypic and molecular characteristics of an Aeromonas hydrophila strain isolated from the River Nile.

    PubMed

    Furmanek-Blaszk, Beata

    2014-01-01

    Aeromonas hydrophila, an inhabitant of aquatic ecosystems found in most parts of the world, has considerable virulence potential. The polymerase chain reaction technique was used to assay for the presence of five virulence factor genes: haemolytic toxins aerA and ahh1, elastase ahyB, the enterotoxin act, and the polar flagella flaA/flaB in the A. hydrophila strain isolated from the River Nile. Drug screening showed high levels of resistance to β-lactam antibiotics and tetracycline. Slime production was determined by the Congo red agar plate test. The isolate produced two restriction enzymes named AehI and AehII which are isoschizomers of XhoI and StuI respectively. The complete nucleotide sequence of the cryptic plasmid pAhy2.5 (2524 bp) from this strain was determined. Sequence analysis revealed the presence of two open reading frames (ORFs) encoding putative proteins. The protein coded by ORF1 is homologous with Rep proteins of plasmids belonging to the pC194 family, which are known to replicate by the rolling-circle mechanism. The putative double-strand origin of replication and a region with palindromic sequences that could function as a single-strand origin were detected in pAhy2.5.

  12. Draft Genome Sequence of Aeromonas sp. Strain EERV15

    PubMed Central

    Ehsani, Elham; Barrantes, Israel; Vandermaesen, Johanna; Geffers, Robert; Jarek, Michael; Boon, Nico; Springael, Dirk; Pieper, Dietmar H.

    2016-01-01

    We report here the draft genome sequence of Aeromonas sp. strain EERV15 isolated from sand filter. The organism most closely related to Aeromonas sp. EERV15 is Aeromonas veronii B565, with an average 83% amino acid sequence similarity of putatively encoded protein open reading frames. PMID:27540061

  13. Draft Genome Sequence of Aeromonas sp. Strain EERV15.

    PubMed

    Ehsani, Elham; Barrantes, Israel; Vandermaesen, Johanna; Geffers, Robert; Jarek, Michael; Boon, Nico; Springael, Dirk; Pieper, Dietmar H; Vilchez-Vargas, Ramiro

    2016-01-01

    We report here the draft genome sequence of Aeromonas sp. strain EERV15 isolated from sand filter. The organism most closely related to Aeromonas sp. EERV15 is Aeromonas veronii B565, with an average 83% amino acid sequence similarity of putatively encoded protein open reading frames. PMID:27540061

  14. Draft Genome Sequence of Aeromonas caviae Strain L12, a Quorum-Sensing Strain Isolated from a Freshwater Lake in Malaysia

    PubMed Central

    Chin, Pui-San; Tee, Kok Keng; Chang, Chien-Yi; Yin, Wai-Fong; Sheng, Kit-Yeng

    2015-01-01

    Here, we present the draft genome sequence of Aeromonas caviae strain L12, which shows quorum-sensing activity. The availability of this genome sequence is important to the research of the quorum-sensing regulatory system in this isolate. PMID:25745006

  15. Arsenic binding to iron(II) minerals produced by an iron(III)-reducing Aeromonas strain isolated from paddy soil.

    PubMed

    Wang, Xin-Jun; Chen, Xue-Ping; Kappler, Andreas; Sun, Guo-Xin; Zhu, Yong-Guan

    2009-11-01

    An iron reducing bacterial strain was isolated from a paddy soil and identified as a member of the Aeromonas group by 16S rRNA gene sequence analysis. When the cells were growing with dissolved Fe(III) as electron acceptor in the presence of As(V), Fe(II) minerals (siderite and vivianite) were formed and dissolved As was removed efficiently from solution. When the cells were growing with the Fe(III) hydroxide mineral (ferrihydrite) as electron acceptor in the presence of As(V), ferrihydrite was reduced and dissolved As(V) concentrations decreased sharply. Our results demonstrated firstly that members of the Aeromonas group can reduce Fe(III) in paddy soils, and secondly that iron reduction does not necessarily lead to arsenic mobilization. However, As immobilization can occur in environments that contain significant concentrations of counter ions such as bicarbonate and phosphate. PMID:19572768

  16. [Factors of virulence associated with enteropathogenicity in strains of Aeromonas spp. isolated from children with diarrhea in Mérida, Venezuela].

    PubMed

    Longa, Aurora; Vizcaya, Luisa; Nieves, Beatriz; Bravo, Laura; Morier, Luis; Pérez-Schael, Irene; Enrique Cabrera, Luis

    2005-01-01

    The feces of 397 patients with acute diarrheal disease (ADD) and of other 121 patients without diarrea (control group) were studied in the state of Mérida, Venezuela, from June 1993 to December 1994. The genus Aeromonas was identified in patients with ADD in 11.83% and in 5.78% of the patients from the control group. On studying the virulence factors described for Aeromonas (enterotoxin, cytotoxin, hemaglutinins, cellular hydrofibrosity, and hemolytic activity) in the isolated strains, it was detected that all presented at least one of the factors investigated associated with enteropathogenicity. Of the isolated species, Aeromonas caviae was the most frequently identified. All these results suggest that the Aeromonas species are potential enteric pathogens in this population.

  17. Enteropathogenicity of Aeromonas species isolated from infants: a cohort study.

    PubMed

    Figueroa, G; Galeno, H; Soto, V; Troncoso, M; Hinrichsen, V; Yudelevich, A

    1988-11-01

    The significance of Aeromonas spp. as potential enteric pathogens was evaluated in a cohort of 187 infants aged 3-18 months during a 16-week summer period. Aeromonas spp. were isolated from 14 of the 196 (7.1%) diarrhoeal episodes detected and from eight (5.2%) of 153 samples from paired asymptomatic infants. Carriage of bacterial enteropathogens excluding Aeromonas spp. was detected in a high proportion (23%) of the asymptomatic children. Almost all of the seven isolates of Aeromonas sobria were enterotoxigenic, invasive and beta-haemolytic. In contrast, none of the seven Aeromonas caviae strains had these virulence-associated characteristics. The only isolate of Aeromonas hydrophila produced cytotoxic enterotoxin and was invasive. Plasmid analysis of selected strains did not correlate with these two properties or with antibiotic resistance. Nevertheless, the latter was found in an important proportion of the isolates. The diarrhoeal episodes, in which Aeromonas spp. were detected, lasted significantly longer, i.e. 17.2 days when the strains were invasive and/or toxigenic as compared with 4.3 days (P less than 0.001) in patients harbouring strains lacking both traits. These results reinforce the need to characterise virulence determinants before assigning any pathogenic role to Aeromonas spp. isolated from faecal specimens. Our findings also suggest the need for adequate antibiotic treatment in patients with confirmed Aeromonas spp. having enterotoxigenic and/or invasive properties.

  18. Aeromonas hydrophila and Aeromonas veronii Predominate among Potentially Pathogenic Ciprofloxacin- and Tetracycline-Resistant Aeromonas Isolates from Lake Erie

    PubMed Central

    Shinko, Jasmine; Augustyniak, Alexander; Gee, Christopher; Andraso, Greg

    2014-01-01

    Members of the genus Aeromonas are ubiquitous in nature and have increasingly been implicated in numerous diseases of humans and other animal taxa. Although some species of aeromonads are human pathogens, their presence, density, and relative abundance are rarely considered in assessing water quality. The objectives of this study were to identify Aeromonas species within Lake Erie, determine their antibiotic resistance patterns, and assess their potential pathogenicity. Aeromonas strains were isolated from Lake Erie water by use of Aeromonas selective agar with and without tetracycline and ciprofloxacin. All isolates were analyzed for hemolytic ability and cytotoxicity against human epithelial cells and were identified to the species level by using 16S rRNA gene restriction fragment length polymorphisms and phylogenetic analysis based on gyrB gene sequences. A molecular virulence profile was identified for each isolate, using multiplex PCR analysis of six virulence genes. We demonstrated that Aeromonas comprised 16% of all culturable bacteria from Lake Erie. Among 119 Aeromonas isolates, six species were identified, though only two species (Aeromonas hydrophila and A. veronii) predominated among tetracycline- and ciprofloxacin-resistant isolates. Additionally, both of these species demonstrated pathogenic phenotypes in vitro. Virulence gene profiles demonstrated a high prevalence of aerolysin and serine protease genes among A. hydrophila and A. veronii isolates, a genetic profile which corresponded with pathogenic phenotypes. Together, our findings demonstrate increased antibiotic resistance among potentially pathogenic strains of aeromonads, illustrating an emerging potential health concern. PMID:24242249

  19. Complete Genome Sequence of the Highly Virulent Aeromonas schubertii Strain WL1483, Isolated from Diseased Snakehead Fish (Channa argus) in China

    PubMed Central

    Liu, Lihui; Li, Ningqiu; Fu, Xiaozhe; Shi, Cunbin; Lin, Qiang

    2016-01-01

    We sequenced the complete genome of the highly virulent Aeromonas schubertii strain WL1483, which was isolated from diseased snakehead fish (Channa argus) in China. The full genome sequence of A. schubertii WL1483 is 4,400,034 bp, which encodes 4,376 proteins and contains 195 predicted RNA genes. PMID:26798095

  20. Complete Genome Sequence of the Highly Virulent Aeromonas schubertii Strain WL1483, Isolated from Diseased Snakehead Fish (Channa argus) in China.

    PubMed

    Liu, Lihui; Li, Ningqiu; Zhang, Defeng; Fu, Xiaozhe; Shi, Cunbin; Lin, Qiang; Hao, Guijie

    2016-01-21

    We sequenced the complete genome of the highly virulent Aeromonas schubertii strain WL1483, which was isolated from diseased snakehead fish (Channa argus) in China. The full genome sequence of A. schubertii WL1483 is 4,400,034 bp, which encodes 4,376 proteins and contains 195 predicted RNA genes.

  1. Isolation and identification of Aeromonas caviae strain KS-1 as TBTC- and lead-resistant estuarine bacteria.

    PubMed

    Shamim, Kashif; Naik, Milind Mohan; Pandey, Anju; Dubey, Santosh Kumar

    2013-06-01

    Tributyltin chloride (TBTC)- and lead-resistant estuarine bacterium from Mandovi estuary, Goa, India was isolated and identified as Aeromonas caviae strain KS-1 based on biochemical characteristics and FAME analysis. It tolerates TBTC and lead up to 1.0 and 1.4 mM, respectively, in the minimal salt medium (MSM) supplemented with 0.4 % glucose. Scanning electron microscopy clearly revealed a unique morphological pattern in the form of long inter-connected chains of bacterial cells on exposure to 1 mM TBTC, whereas cells remained unaltered in presence of 1.4 mM Pb(NO₃)₂ but significant biosorption of lead (8 %) on the cell surface of this isolate was clearly revealed by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. SDS-PAGE analysis of whole-cell proteins of this lead-resistant isolate interestingly demonstrated three lead-induced proteins with molecular mass of 15.7, 16.9 and 32.4 kDa, respectively, when bacterial cells were grown under the stress of 1.4 mM Pb (NO₃)₂. This clearly demonstrated their possible involvement exclusively in lead resistance. A. caviae strain KS-1 also showed tolerance to several other heavy metals, viz. zinc, cadmium, copper and mercury. Therefore, we can employ this TBTC and lead-resistant bacterial isolate for lead bioremediation and also for biomonitoring TBTC from lead and TBTC contaminated environment.

  2. Isolation of a pigment-producing strain of Aeromonas liquefaciens from silver salmon (Oncorhynchus kisutch)

    USGS Publications Warehouse

    Ross, A.J.

    1962-01-01

    Aeromonas salmonicida, the etiological agent of furunculosis in fish, is distinctive in the field of fish diseases in that it may readily be recognized by the water-soluble reddish-brown pigment formed on culture media containing tyrosine. Additional tests for the identification of this organism include blackening of the colonial growth when flooded with an aqueous solution of p-phenylenediamine and a lack of motility (Griffin, Progressive Fish Culturist 14:74, 1952).

  3. Molecular mechanisms of quinolone resistance in clinical isolates of Aeromonas caviae and Aeromonas veronii bv. sobria.

    PubMed

    Arias, Antonina; Seral, Cristina; Gude, M José; Castillo, F Javier

    2010-09-01

    Mutations in quinolone targets were studied together with quinolone efflux pump activation and plasmid-mediated quinolone resistance determinants in nalidixic-acid-resistant isolates of Aeromonas caviae and Aeromonas veronii. Among 135 clinical Aeromonas spp. isolated from stools of patients with gastrointestinal symptoms, 40 nalidixic acid-resistant strains belonging to A. caviae and A. veronii were selected and their susceptibility to different quinolones (ciprofloxacin, norfloxacin, ofloxacin) further evaluated. Susceptibility to nalidixic acid and ciprofloxacin in the presence/absence of Phe- Arg-β-naphthylamide was also determined. The 16 nalidixic-acid-resistant strains identified as A. caviae were more resistant than the 24 A. veronii bv. sobria strains to ciprofloxacin, norfloxacin, and ofloxacin. All strains showed a mutation (single or double) at position 83 of the QRDR sequence of gyrA, with Ser-83 → Ile as the most frequent substitution. By contrast, no mutations were found at position 87 of gyrA. Double substitutions (GyrA-ParC) were detected in 50% of A. veronii bv. sobria isolates and in 43.75% of A. caviae strains. Both species showed decreases in the MICs of ciprofloxacin. A qnrS gene was found in an A. caviae strain. Thus, in the two species of nalidixic-acid-resistant Aeromonas isolates examined, resistance mediated by efflux pumps contributed only slightly to ciprofloxacin resistance. While two isolates were positive for the aac(6')-Ib gene, no -cr variants were detected.

  4. Draft Genome Sequence of the Aeromonas diversa Type Strain.

    PubMed

    Farfán, Maribel; Spataro, Nino; Sanglas, Ariadna; Albarral, Vicenta; Lorén, J Gaspar; Bosch, Elena; Fusté, M Carmen

    2013-06-27

    We present here the first genome sequence of the Aeromonas diversa type strain (CECT 4254(T)). This strain was isolated from the leg wound of a patient in New Orleans (Louisiana) and was originally described as enteric group 501 and distinguished from A. schubertii by DNA-DNA hybridization and phenotypical characterization.

  5. Improvement of methyl orange dye biotreatment by a novel isolated strain, Aeromonas veronii GRI, by SPB1 biosurfactant addition.

    PubMed

    Mnif, Inès; Maktouf, Sameh; Fendri, Raouia; Kriaa, Mouna; Ellouze, Semia; Ghribi, Dhouha

    2016-01-01

    Aeromonas veronii GRI (KF964486), isolated from acclimated textile effluent after selective enrichment on azo dye, was assessed for methyl orange biodegradation potency. Results suggested the potential of this bacterium for use in effective treatment of azo-dye-contaminated wastewaters under static conditions at neutral and alkaline pH value, characteristic of typical textile effluents. The strain could tolerate higher doses of dyes as it was able to decolorize up to 1000 mg/l. When used as microbial surfactant to enhance methyl orange biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized slightly the decolorization efficiency at an optimal concentration of about 0.025%. In order to enhance the process efficiency, a Taguchi design was conducted. Phytotoxicity bioassay using sesame and radish seeds were carried out to assess the biotreatment effectiveness. The bacterium was able to effectively decolorize the azo dye when inoculated with an initial optical density of about 0.5 with 0.25% sucrose, 0.125% yeast extract, 0.01% SPB1 biosurfactant, and when conducting an agitation phase of about 24 h after static incubation. Germination potency showed an increase toward the nonoptimized conditions indicating an improvement of the biotreatment. When comparing with synthetic surfactants, a drastic decrease and an inhibition of orange methyl decolorization were observed in the presence of CTAB and SDS. The nonionic surfactant Tween 80 had a positive effect on methyl orange biodecolorization. Also, studies ensured that methyl orange removal by this strain could be due to endocellular enzymatic activities. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing effective decolorization period, biosurfactant stimulated bacterial decolorization method may provide highly efficient, inexpensive, and time-saving procedure in treatment of textile effluents. PMID:26396008

  6. Improvement of methyl orange dye biotreatment by a novel isolated strain, Aeromonas veronii GRI, by SPB1 biosurfactant addition.

    PubMed

    Mnif, Inès; Maktouf, Sameh; Fendri, Raouia; Kriaa, Mouna; Ellouze, Semia; Ghribi, Dhouha

    2016-01-01

    Aeromonas veronii GRI (KF964486), isolated from acclimated textile effluent after selective enrichment on azo dye, was assessed for methyl orange biodegradation potency. Results suggested the potential of this bacterium for use in effective treatment of azo-dye-contaminated wastewaters under static conditions at neutral and alkaline pH value, characteristic of typical textile effluents. The strain could tolerate higher doses of dyes as it was able to decolorize up to 1000 mg/l. When used as microbial surfactant to enhance methyl orange biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized slightly the decolorization efficiency at an optimal concentration of about 0.025%. In order to enhance the process efficiency, a Taguchi design was conducted. Phytotoxicity bioassay using sesame and radish seeds were carried out to assess the biotreatment effectiveness. The bacterium was able to effectively decolorize the azo dye when inoculated with an initial optical density of about 0.5 with 0.25% sucrose, 0.125% yeast extract, 0.01% SPB1 biosurfactant, and when conducting an agitation phase of about 24 h after static incubation. Germination potency showed an increase toward the nonoptimized conditions indicating an improvement of the biotreatment. When comparing with synthetic surfactants, a drastic decrease and an inhibition of orange methyl decolorization were observed in the presence of CTAB and SDS. The nonionic surfactant Tween 80 had a positive effect on methyl orange biodecolorization. Also, studies ensured that methyl orange removal by this strain could be due to endocellular enzymatic activities. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing effective decolorization period, biosurfactant stimulated bacterial decolorization method may provide highly efficient, inexpensive, and time-saving procedure in treatment of textile effluents.

  7. Electrochemical Characterization of a Novel Exoelectrogenic Bacterium Strain SCS5, Isolated from a Mediator-Less Microbial Fuel Cell and Phylogenetically Related to Aeromonas jandaei

    PubMed Central

    Sharma, Subed Chandra Dev; Feng, Cuijie; Li, Jiangwei; Hu, Anyi; Wang, Han; Qin, Dan; Yu, Chang-Ping

    2016-01-01

    A facultative anaerobic bacterium, designated as strain SCS5, was isolated from the anodic biofilm of a mediator-less microbial fuel cell using acetate as the electron donor and α-FeOOH as the electron acceptor. The isolate was Gram-negative, motile, and shaped as short rods (0.9–1.3 μm in length and 0.4–0.5 μm in width). A phylogenetic analysis of the 16S rRNA, gyrB, and rpoD genes suggested that strain SCS5 belonged to the Aeromonas genus in the Aeromonadaceae family and exhibited the highest 16S rRNA gene sequence similarity (99.45%) with Aeromonas jandaei ATCC 49568. However, phenotypic, cellular fatty acid profile, and DNA G+C content analyses revealed that there were some distinctions between strain SCS5 and the type strain A. jandaei ATCC 49568. The optimum growth temperature, pH, and NaCl (%) for strain SCS5 were 35°C, 7.0, and 0.5% respectively. The DNA G+C content of strain SCS5 was 59.18%. The isolate SCS5 was capable of reducing insoluble iron oxide (α-FeOOH) and transferring electrons to extracellular material (the carbon electrode). The electrochemical activity of strain SCS5 was corroborated by cyclic voltammetry and a Raman spectroscopic analysis. The cyclic voltammogram of strain SCS5 revealed two pairs of oxidation-reduction peaks under anaerobic and aerobic conditions. In contrast, no redox pair was observed for A. jandaei ATCC 49568. Thus, isolated strain SCS5 is a novel exoelectrogenic bacterium phylogenetically related to A. jandaei, but shows distinct electrochemical activity from its close relative A. jandaei ATCC 49568. PMID:27396922

  8. Draft Genome Sequence of Aeromonas dhakensis Strain F2S2-1, Isolated from the Skin Surface of an Indian Oil Sardine (Sardinella longiceps).

    PubMed

    Nadiga, Mohan; Vaidyanathan, V V; Thayumanavan, Thangavelu

    2016-01-01

    Draft genome sequencing of Aeromonas dhakensis strain F2S2-1, isolated from the skin surface of an Indian oil sardine (Sardinella longiceps), has been carried out. The draft genome was roughly 4.7 Mb in size with 61.7% G+C content. Annotation of the genome yielded 4,337 genes coding for proteins, tRNAs, and rRNAs. Annotation also revealed the presence of 52 genes linked to resistance to antibiotics/toxic compounds. Pathway analysis revealed the presence of novobiocin biosynthetic genes and genes for biosynthesis of a siderophore group on nonsynthetic peptides. PMID:27540048

  9. Draft Genome Sequence of Aeromonas dhakensis Strain F2S2-1, Isolated from the Skin Surface of an Indian Oil Sardine (Sardinella longiceps)

    PubMed Central

    Nadiga, Mohan; Vaidyanathan, V. V.

    2016-01-01

    Draft genome sequencing of Aeromonas dhakensis strain F2S2-1, isolated from the skin surface of an Indian oil sardine (Sardinella longiceps), has been carried out. The draft genome was roughly 4.7 Mb in size with 61.7% G+C content. Annotation of the genome yielded 4,337 genes coding for proteins, tRNAs, and rRNAs. Annotation also revealed the presence of 52 genes linked to resistance to antibiotics/toxic compounds. Pathway analysis revealed the presence of novobiocin biosynthetic genes and genes for biosynthesis of a siderophore group on nonsynthetic peptides. PMID:27540048

  10. Characterisation of Aeromonas spp. isolated from frozen fish intended for human consumption in Mexico.

    PubMed

    Castro-Escarpulli, G; Figueras, M J; Aguilera-Arreola, G; Soler, L; Fernández-Rendón, E; Aparicio, G O; Guarro, J; Chacón, M R

    2003-07-15

    A total of 82 strains of presumptive Aeromonas spp. were identified biochemically and genetically (16S rDNA-RFLP). The strains were isolated from 250 samples of frozen fish (Tilapia, Oreochromis niloticus niloticus) purchased in local markets in Mexico City. In the present study, we detected the presence of several genes encoding for putative virulence factors and phenotypic activities that may play an important role in bacterial infection. In addition, we studied the antimicrobial patterns of those strains. Molecular identification demonstrated that the prevalent species in frozen fish were Aeromonas salmonicida (67.5%) and Aeromonas bestiarum (20.9%), accounting for 88.3% of the isolates, while the other strains belonged to the species Aeromonas veronii (5.2%), Aeromonas encheleia (3.9%) and Aeromonas hydrophila (2.6%). Detection by polymerase chain reaction (PCR) of genes encoding putative virulence factors common in Aeromonas, such as aerolysin/hemolysin, lipases including the glycerophospholipid-cholesterol acyltransferase (GCAT), serine protease and DNases, revealed that they were all common in these strains. Our results showed that first generation quinolones and second and third generation cephalosporins were the drugs with the best antimicrobial effect against Aeromonas spp. In Mexico, there have been few studies on Aeromonas and its putative virulence factors. The present work therefore highlights an important incidence of Aeromonas spp., with virulence potential and antimicrobial resistance, isolated from frozen fish intended for human consumption in Mexico City. PMID:12781953

  11. Aeromonas salmonicida subsp. salmonicida strains isolated from Chinese freshwater fish contain a novel genomic island and possible regional-specific mobile genetic elements profiles.

    PubMed

    Long, Meng; Nielsen, Tue K; Leisner, Jørgen J; Hansen, Lars H; Shen, Zhi X; Zhang, Qian Q; Li, Aihua

    2016-09-01

    Two strains of Aeromonas salmonicida, YK and BG, were isolated from largemouth bronze gudgeon and northern whitefish in China, and identified as A. salmonicida subsp. salmonicida based on phylogenetic analysis of vapA and 16S rRNA gene sequences. YK and BG originated from freshwater fish, one of which belonged to the cyprinid family, and the strains showed a difference in virulence. Subsequently, we performed whole genome sequencing of the strains, and comparison of their genomic sequences to the genome of the A449 reference strain revealed various genomic rearrangements, including a new variant of the genomic island AsaGEI in BG, designated as AsaGEI2c This is the first report on a GEI of A. salmonicida strain from China. Furthermore, both YK and BG strains contained a Tn7 transposon inserted at the same position in the chromosome. Finally, IS-dependent rearrangements on pAsa5 are deemed likely to have occurred, with omission of the resD gene in both strains as well as omission of genes related to the IncF conjugal transfer system in the YK isolate. This study demonstrates that A. salmonicida subsp. salmonicida can infect non-salmonids (cyprinids) in addition to salmonids, and that AsaGEI2c might be useful as a geographical indicator of Chinese A. salmonicida subsp. salmonicida isolates. PMID:27493011

  12. Isolation of Aeromonas species from clinical sources

    PubMed Central

    McCracken, A. W.; Barkley, R.

    1972-01-01

    In a period of one year, in a general hospital, Aeromonas hydrophila was isolated from 13 patients and Aeromonas shigelloides from one patient. Eight of the patients had superficial infections, two had urinary tract infections, and four had bacteriaemia. The association of Aeromonas bacteriaemia with cirrhosis of the liver and malignant disease, which has been previously reported, was observed in three of the four bacteriaemic patients. The key to laboratory diagnosis of this genus is the routine performance of the oxidase test in bacteriological procedures for the identification of Gram-negative bacilli. PMID:4567553

  13. Production of Non-Ribosomal Peptide Synthetase (NRPS)- Dependent Siderophore by Aeromonas Isolates

    PubMed Central

    Amsaveni, Ramasamy; Sureshkumar, Muthusamy; Aravinth, Arthanari; Mary, Joseph Reshma; Vivekanandhan, Govindasami

    2016-01-01

    Background: Aeromonas species are Gram-negative ubiquitous bacteria, facultative anaerobic rods that infect both invertebrates and vertebrates. Various fish species develop hemorrhagic disease and furunculosis due to Aeromonas spp. Aeromonas strains generate certain active compounds such as siderophores, which are the final products of non-ribosomal peptide synthetase (NRPS) activity. The present study attempted to investigate the prevalence of Aeromonas isolates in marketed fish sources. We also examined the siderophore production ability of these isolates. Methods: Among the molecular tools, 16S rRNA analysis was used to identify Aeromonas species and their epidemiological distributions. The hemolytic activity of the strains and biochemical assays were used to confirm the identity of the isolates. We also determined the chemical nature of siderophores in these strains. Results: A total of seven Aeromonas isolates obtained from fish were included to determine the siderophore production. Of 7 isolates, 4 produced siderophore, and their chemical nature was also determined. The siderophore produced by Aeromonas was invariably found to be of hydroxamate. Four Aeromonas isolates were selected for PCR identification of NRPS-encoding gene. The conserved sequence was present in all four selected isolates. Furthermore, siderophores were qualitatively tested for their antibacterial activity against pathogenic bacteria and a significant level of inhibitory activity was observed in siderophores from the four isolates. Conclusion: Our results showed the ability of the isolated strains in production of siderophores with a high level of activity against Salmonella paratyphi. These siderophores could find applications in biomedical industries. PMID:27155016

  14. Antimicrobial Susceptibilities of Aeromonas spp. Isolated from Environmental Sources▿

    PubMed Central

    Huddleston, Jennifer R.; Zak, John C.; Jeter, Randall M.

    2006-01-01

    Aeromonas spp. are ubiquitous aquatic bacteria that cause serious infections in both poikilothermic and endothermic animals, including humans. Clinical isolates have shown an increasing incidence of antibiotic and antimicrobial drug resistance since the widespread use of antibiotics began. A total of 282 Aeromonas pure cultures were isolated from both urban and rural playa lakes in the vicinity of Lubbock, Texas, and several rivers in West Texas and New Mexico. Of these, at least 104 were subsequently confirmed to be independent isolates. The 104 isolates were identified by Biolog and belonged to 11 different species. The MICs of six metals, one metalloid, five antibiotics, and two antimicrobial drugs were determined. All aeromonads were sensitive to chromate, cobalt, copper, nickel, zinc, cefuroxime, kanamycin, nalidixic acid, ofloxacin, tetracycline, and sulfamethoxazole. Low incidences of trimethoprim resistance, mercury resistance, and arsenite resistance were found. Dual resistances were found in 5 of the 104 Aeromonas isolates. Greater numbers of resistant isolates were obtained from samples taken in March versus July 2002 and from sediment versus water. Plasmids were isolated from selected strains of the arsenite- and mercury-resistant organisms and were transformed into Escherichia coli XL1-Blue MRF′. Acquisition of the resistance phenotypes by the new host showed that these resistance genes were carried on the plasmids. Mercury resistance was found to be encoded on a conjugative plasmid. Despite the low incidence of resistant isolates, the six playa lakes and three rivers that were sampled in this study can be considered a reservoir for antimicrobial resistance genes. PMID:16950901

  15. Draft Genome Sequence of Aeromonas hydrophila Strain Ae34, Isolated from a Septicemic and Moribund Koi Carp (Cyprinus carpio koi), a Freshwater Aquarium Fish.

    PubMed

    Jagoda, S S S De S; Tan, Engkong; Arulkanthan, Appudurai; Kinoshita, Shigeharu; Watabe, Shugo; Asakawa, Shuichi

    2014-06-12

    Aeromonas hydrophila is an important opportunistic pathogen that infects a variety of aquatic and terrestrial animals, including humans. We report here the draft genome sequence of A. hydrophila Ae34, a multidrug-resistant isolate from the kidney of a moribund koi carp (Ciprinus carpio koi) with signs of hemorrhagic septicemia.

  16. Virulence and antimicrobial susceptibility of clinical and environmental strains of Aeromonas spp. from northeastern Brazil.

    PubMed

    Castelo-Branco, Débora de Souza Collares Maia; Guedes, Glaucia Morgana de Melo; Brilhante, Raimunda Sâmia Nogueira; Rocha, Marcos Fábio Gadelha; Sidrim, José Júlio Costa; Moreira, José Luciano Bezerra; Cordeiro, Rossana de Aguiar; Sales, Jamille Alencar; Riello, Giovanna Barbosa; de Alencar, Lucas Pereira; Paiva, Manoel de Araújo Neto; Vasconcelos, David Caldas; de Menezes, Isis Sousa Bezerra; de Ponte, Yago Brito; Sampaio, Célia Maria de Souza; Monteiro, André Jalles; Bandeira, Tereza de Jesus Pinheiro Gomes

    2015-08-01

    The aims of the present study were to isolate and identify clinical and environmental strains of Aeromonas spp. by means of biochemical tests and the automated method VITEK 2 and to investigate the presence of the virulence genes cytotoxic enterotoxin (act), hemolysin (asa-1), and type III secretion system (ascV), and also the in vitro antimicrobial susceptibility of the strains. From the clinical isolates, 19 Aeromonas hydrophila, 3 Aeromonas veronii bv. sobria, and 1 Aeromonas caviae were identified, while from the environmental strains, 11 A. hydrophila, 22 A. veronii bv. sobria, 1 A. veronii bv. veronii, and 1 A. caviae were recovered. The gene act was detected in 69.5% of clinical isolates, asa-1 in 8.6%, and ascV in 34.7%. In the environmental strains, the detection rates were 51.4%, 45.7%, and 54.2% for the genes act, asa-1, and ascV, respectively. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was observed in 15 and 3 clinical strains, respectively, and resistance to ceftazidime, meropenem, imipenem, ciprofloxacin, and trimethoprim-sulfamethoxazole was observed in 1 strain for each drug. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was detected in 17 and 1 environmental strain, respectively. Higher resistance percentages were observed in clinical strains, but environmental strains also showed this phenomenon and presented a higher detection rate of virulence genes. Thus, it is important to monitor the antimicrobial susceptibility and pathogenic potential of the environmental isolates.

  17. The occurrence of cytotoxic Aeromonas hydrophila strains in Italian mineral and thermal waters.

    PubMed

    Biscardi, D; Castaldo, A; Gualillo, O; de Fusco, R

    2002-06-26

    Bacteria of the genus Aeromonas are ubiquitous in aquatic environments, including mineral drinking and thermal waters. Motile species are related to different diseases, mostly gastrointestinal disorders. Criteria for Aeromonas pathogenicity in humans and animals are still unclear and neither is the relationship between production virulence and pathogenicity factors. In the present study, strains of Aeromonas hydrophila, from 61 samples of bottled mineral waters and 23 thermal Italian sources have been isolated and identified by biochemical tests, for toxicity and detection of the aerolysin gene by the Polymerase Chain Reaction (PCR). Six strains were isolated from the mineral waters and were found to be cytotoxic and in possession of the aerolysin gene. For the twelve strains isolated from thermal waters, seven were cytotoxic and eleven contained the aerolysin gene.

  18. Identification and epidemiological relationships of Aeromonas isolates from patients with diarrhea, drinking water and foods.

    PubMed

    Pablos, M; Huys, G; Cnockaert, M; Rodríguez-Calleja, J M; Otero, A; Santos, J A; García-López, M L

    2011-06-30

    A collection of Aeromonas isolates obtained over a three-year period in the same geographic area (León, NW of Spain) was characterized by (GTG)₅-PCR fingerprinting, amplified fragment length polymorphism (AFLP) analysis and gyrB gene sequence analysis. The isolates originated from human diarrheal stools (29 isolates), potable water (13 isolates), rabbit meat (13 isolates) and marine fish (5 isolates). The distribution of Aeromonas species varied with the strain source. Aeromonas caviae HG4 and Aeromonas media HG5 were predominant in clinical and water isolates, respectively, whereas motile Aeromonas salmonicida HG3 strains were most frequently found in fish and meat. Molecular typing revealed several genotypic relationships among specific isolate subsets: (i) two clones of A. media HG5 persisted in drinking water over the study period, (ii) different patients harbored identical or closely related clones during several months, and (iii) clonal relatedness was observed in two sets of water and human isolates. The first of these sets comprised nine water isolates and two human A. media HG5 isolates, whereas the other one included a water isolate and a human isolate of A. caviae HG4. The latter finding suggests that Aeromonas transmission in the studied region followed a waterborne route. Interestingly, the three human isolates closely related to water isolates were recovered in a period of four days in June 2006 from non-related patients without underlying medical conditions that tested negative for other enteric pathogens. The data imply the transmission through contaminated water of strains of the A. caviae group that can produce disease in humans.

  19. AQU-1, a chromosomal class C β-lactamase, among clinical Aeromonas dhakensis isolates: distribution and clinical significance.

    PubMed

    Wu, Chi-Jung; Wang, Hsuan-Chen; Chen, Po-Lin; Chang, Ming-Chung; Sunny Sun, H; Chou, Pei-Hsin; Ko, Wen-Chien

    2013-11-01

    Aeromonas dhakensis, a recently described Aeromonas sp. formerly called Aeromonas aquariorum, is associated with human infections. In this study, a chromosomal gene, blaAQU-1, was identified in A. dhakensis AAK1 that constitutes a 1143-bp open reading frame and is 87% identical to the gene encoding CepH in Aeromonas hydrophila. An Escherichia coli TOP10 cell transformant harbouring blaAQU-1 was resistant to cefotaxime but not to cefepime. mRNA expression of blaAQU-1 in the cefotaxime-resistant mutant strain AAK1m was 70-fold higher than in the wild strain AAK1. In all 16 A. dhakensis isolates (the major species of 51 consecutive Aeromonas blood isolates collected from June 1999 to June 2001) as well as in A. aquariorum MDC47(T) and A. hydrophila subsp. dhakensis LMG 19562(T), but not in the reference strains or clinical isolates of other A. hydrophila subspecies, Aeromonas caviae, Aeromonas veronii or Aeromonas enteropelogenes, blaAQU-1-related genes were detected by PCR. Overall, 13 (81%) of the 16 A. dhakensis blood isolates exhibited either cefotaxime resistance or the in vitro emergence of derepressed cefotaxime-resistant mutants. In vivo selection of an A. dhakensis resistant mutant was noted in a burn patient undergoing cefotaxime monotherapy. These observations suggest that AQU-1 is a chromosomal cephalosporinase in A. dhakensis. Cefotaxime monotherapy for severe A. dhakensis infections should be used cautiously.

  20. Lectin-binding properties of Aeromonas caviae strains

    PubMed Central

    Rocha-de-Souza, Cláudio M.; Hirata-Jr, Raphael; Mattos-Guaraldi, Ana L.; Freitas-Almeida, Angela C.; Andrade, Arnaldo F. B.

    2008-01-01

    The cell surface carbohydrates of four strains of Aeromonas caviae were analyzed by agglutination and lectin-binding assays employing twenty highly purified lectins encompassing all sugar specificities. With the exception of L-fucose and sialic acid, the sugar residues were detected in A. caviae strains. A marked difference, however, in the pattern of cell surface carbohydrates in different A. caviae isolates was observed. Specific receptors for Tritricum vulgaris (WGA), Lycopersicon esculentum (LEL) and Solanum tuberosum (STA) (D-GlcNAc-binding lectins) were found only in ATCC 15468 strain, whereas Euonymus europaeus (EEL, D-Gal-binding lectin) sites were present exclusively in AeQ32 strain, those for Helix pomatia (HPA, D-GalNAc-binding lectin) in AeC398 and AeV11 strains, and for Canavalia ensiformes (Con A, D-Man-binding lectin) in ATCC 15468, AeC398, AeQ32 and AeV11 strains, after bacterial growing at 37°C. On the other hand, specific receptors for WGA and EEL were completely abrogated growing the bacteria at 22°C. Binding studies with 125I- labeled lectins from WGA, EEL and Con A were performed. These assays essentially confirmed the selectivity, demonstrated in the agglutination assays of these lectins for the A. caviae strains. PMID:24031204

  1. Draft genome sequences of four virulent aeromonas hydrophila strains from catfish aquaculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 2009, a clonal group of virulent Aeromonas hydrophila (VAh) strains has been causing severe disease in the catfish aquaculture industry in the Southeastern United States. Here, we report draft genomes of four A. hydrophila isolates from catfish aquaculture that represent this clonal group....

  2. Genome Sequence of Aeromonas hydrophila Strain AH-3 (Serotype O34)

    PubMed Central

    Forn-Cuní, Gabriel; Tomás, Juan M.

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of poikilothermic animals, from fish to mammals, including humans. Here, we report the whole-genome sequence of the A. hydrophila AH-3 strain, isolated from a fish farm goldfish septicemia outbreak in Spain, with a characterized polar and lateral flagellum glycosylation pattern. PMID:27587828

  3. Draft Genome Sequences of Four Virulent Aeromonas hydrophila Strains from Catfish Aquaculture.

    PubMed

    Tekedar, Hasan C; Kumru, Salih; Karsi, Attila; Waldbieser, Geoffrey C; Sonstegard, Tad; Schroeder, Steven G; Liles, Mark R; Griffin, Matt J; Lawrence, Mark L

    2016-01-01

    Since 2009, a clonal group of virulent Aeromonas hydrophila strains has been causing severe disease in the catfish aquaculture industry in the southeastern United States. Here, we report draft genomes of four A. hydrophila isolates from catfish aquaculture that represent this clonal group.

  4. Genome Sequence of Aeromonas hydrophila Strain AH-3 (Serotype O34).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-09-01

    Aeromonas hydrophila is an emerging pathogen of poikilothermic animals, from fish to mammals, including humans. Here, we report the whole-genome sequence of the A. hydrophila AH-3 strain, isolated from a fish farm goldfish septicemia outbreak in Spain, with a characterized polar and lateral flagellum glycosylation pattern.

  5. Genome Sequence of Aeromonas hydrophila Strain AH-3 (Serotype O34).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of poikilothermic animals, from fish to mammals, including humans. Here, we report the whole-genome sequence of the A. hydrophila AH-3 strain, isolated from a fish farm goldfish septicemia outbreak in Spain, with a characterized polar and lateral flagellum glycosylation pattern. PMID:27587828

  6. Whole-Genome Sequencing Analysis of Quorum-Sensing Aeromonas hydrophila Strain M023 from Freshwater.

    PubMed

    Tan, Wen-Si; Yin, Wai-Fong; Chang, Chien-Yi; Chan, Kok-Gan

    2015-01-01

    Aeromonas hydrophila is a well-known waterborne pathogen that recently was found to infect humans. Here, we report the draft genome of a freshwater isolate from a Malaysian waterfall, A. hydrophila strain M023, which portrays N-acylhomoserine lactone-dependent quorum sensing. PMID:25700404

  7. Draft Genome Sequences of Four Virulent Aeromonas hydrophila Strains from Catfish Aquaculture

    PubMed Central

    Tekedar, Hasan C.; Kumru, Salih; Karsi, Attila; Waldbieser, Geoffrey C.; Sonstegard, Tad; Schroeder, Steven G.; Liles, Mark R.; Griffin, Matt J.

    2016-01-01

    Since 2009, a clonal group of virulent Aeromonas hydrophila strains has been causing severe disease in the catfish aquaculture industry in the southeastern United States. Here, we report draft genomes of four A. hydrophila isolates from catfish aquaculture that represent this clonal group. PMID:27540076

  8. An alternative bacteriological medium for the isolation of Aeromonas spp.

    USGS Publications Warehouse

    Jenkins, J.A.; Taylor, P.W.

    1995-01-01

    Two solid bacteriologic media were compared for cultivating Aeromonas spp. from piscine sources: the Rimler-Shotts (RS) medium and a starch-glutamate-ampicillin-penicillin-based medium (SGAP-10C) used for the recovery of Aeromonas spp. from water samples. The selective and differential capacities of the media were assessed March through October 1992 by recovery rate and phenotype of 99 isolates representing 15 genera of bacteria. Recovery frequency of Aeromonas spp. (n = 62) was similar at 97% on RS and 95% on SGAP-10C. The SGAP-10C medium proved to be more specific than RS toward Aeromonas species (P ≤ 0.005). Use of SGAP-10C at 24 C for 48 hr offers a better choice for the laboratory recovery of Aeromonas spp. from clinical fish specimens.

  9. Dynamics of Aeromonas species isolated from wastewater treatment system.

    PubMed

    Martone-Rocha, S; Piveli, R P; Matté, G R; Dória, M C; Dropa, M; Morita, M; Peternella, F A; Matté, M H

    2010-12-01

    Aeromonas are widely distributed in the aquatic environment, and are considered to be emerging organisms that can produce a series of virulence factors. The present study was carried out in a sanitary sewage stabilization pond treatment system, located in Lins, State of São Paulo, Brazil. Most probable number was applied for estimation of the genus Aeromonas. Colony isolation was carried out on blood agar ampicillin and confirmed by biochemical characterization. Aeromonas species were isolated in 72.4% of influent samples, and in 55.2 and 48.3% of effluent from anaerobic and facultative lagoons, respectively. Thirteen Aeromonas species were isolated, representing most of the recognized species of these organisms. Even though it was possible to observe a tendency of decrease, total elimination of these organisms from the studied system was not achieved. Understanding of the pathogenic organism's dynamics in wastewater treatment systems with a reuse potential is especially important because of the risk it represents. PMID:20705981

  10. Prevalence, characterization, and antimicrobial resistance of Aeromonas strains from various retail food products in Mumbai, India.

    PubMed

    Nagar, Vandan; Shashidhar, Ravindranath; Bandekar, Jayant R

    2011-09-01

    A total of 154 food samples (chicken, fish, and ready-to-eat sprouts) from various retail outlets in Mumbai, India, were analyzed for the presence of Aeromonas spp. over a period of 2 y (January 2006 to March 2008). Twenty-two Aeromonas isolates belonging to 7 different species were isolated from 18 (11.7%) food samples. The highest percentages of isolation were from chicken (28.6%) followed by fish (20%) and sprout (2.5%) samples. Aeromonas caviae, A. veronii bv. sobria, and A. salmonicida were the most frequently isolated species from sprouts, chicken, and fish samples, respectively. The genes encoding for putative virulence factors, cytotoxic enterotoxin (act), hemolysin (hly), aerolysin (aer), elastase (ahyB), and lipase (lip) were detected using polymerase chain reaction method in 59.1%, 40.9%, 22.7%, 54.5%, and 31.8% of the strains, respectively. The isolated Aeromonas strains were found to be positive for virulence factors, that is, amylase, DNase, gelatinase, protease, and lipase production. More than 60% isolates were also positive for β-hemolytic activity. All these food isolates were found to be resistant to ampicillin and bacitracin, and sensitive to gentamicin, 3rd-generation cephalosporins (ceftazidime, cephotaxime, ceftriaxone), and chloramphenicol. Seventeen (77.2%) isolates harbored single and/or multiple plasmids (approximately 5 to >16 kb). The XbaI digestion patterns of chromosomal DNA of these isolates, using pulsed field gel electrophoresis, showed high genetic diversity among these isolates. Our results demonstrate the presence of various Aeromonas spp. with virulence potential and antimicrobial resistance in different food products marketed in Mumbai, India. The potential health risks posed by consumption of these raw or undercooked food products should not be underestimated.

  11. Molecular characterization of fluoroquinolone-resistant Aeromonas spp. isolated from imported shrimp.

    PubMed

    Shakir, Zakiya; Khan, Saeed; Sung, Kidon; Khare, Sangeeta; Khan, Ashraf; Steele, Roger; Nawaz, Mohamed

    2012-11-01

    Sixty-three nalidixic acid-resistant Aeromonas sp. isolates were obtained from imported shrimp. Phylogenetic analysis of gyrB sequences indicated that 18 were A. enteropelogenes, 26 were A. caviae, and 19 were A. sobria. Double missense mutations in the quinolone resistance-determining region (QRDR) of gyrA at codon 83 (Ser→Val/Ile) and codon 92 (Leu→Met) coupled with a point mutation of parC at codon 80 (Ser→Ile/Phe) conferred high levels of quinolone resistance in the isolates. A majority of A. enteropelogenes and A. caviae strains harbored toxin genes, whereas only a few A. sobria strains harbored these genes. The fluoroquinolone-resistant Aeromonas spp. exhibited higher cytotoxicity than fluoroquinolone-sensitive, virulent Aeromonas spp. to rat epithelial cells.

  12. Aeromonas species isolated from medicinal leeches.

    PubMed

    Mackay, D R; Manders, E K; Saggers, G C; Banducci, D R; Prinsloo, J; Klugman, K

    1999-03-01

    Aeromonas hydrophila infections are a recognized complication of the use of medicinal leeches. The authors performed an experiment designed to find a safe and practical way to sterilize the leech gut of pathogenic organisms. Leeches were incubated for a 12-hour period in solutions of antibiotic effective against A. hydrophila. The incubations in the antibiotic solutions failed to eradicate pathogenic bacteria from the gut of the leeches. The authors examined cultures of bacteria isolated from the guts of the commonly used Hirudo medicinalis (European leech) and found a wide variety of pathogenic organisms. A. hydrophila is widely believed to be the most common enteric pathogen, but the authors found A. sobria more frequently in their experiment. They also cultured the guts of the leech H. michaelseni recently used clinically in South Africa. A. caviae was the most common pathogen encountered in these leeches. A. caviae and A. sobria cause a spectra of disease similar to A. hydrophila. The authors endorse the current recommendation that all patients who have leech therapy for congested flaps or replants receive broad-spectrum prophylactic antibiotics. This appears to be the safest and simplest way to prevent leech-related infections.

  13. Phenotypic and Genetic Diversity of Aeromonas Species Isolated from Fresh Water Lakes in Malaysia

    PubMed Central

    Khor, Wei Ching; Puah, Suat Moi; Tan, Jin Ai Mary Anne; Puthucheary, SD; Chua, Kek Heng

    2015-01-01

    Gram-negative bacilli of the genus Aeromonas are primarily inhabitants of the aquatic environment. Humans acquire this organism from a wide range of food and water sources as well as during aquatic recreational activities. In the present study, the diversity and distribution of Aeromonas species from freshwater lakes in Malaysia was investigated using glycerophospholipid-cholesterol acyltransferase (GCAT) and RNA polymerase sigma-factor (rpoD) genes for speciation. A total of 122 possible Aeromonas strains were isolated and confirmed to genus level using the API20E system. The clonality of the isolates was investigated using ERIC-PCR and 20 duplicate isolates were excluded from the study. The specific GCAT-PCR identified all isolates as belonging to the genus Aeromonas, in agreement with the biochemical identification. A phylogenetic tree was constructed using the rpoD gene sequence and all 102 isolates were identified as: A. veronii 43%, A. jandaei 37%, A. hydrophila 6%, A. caviae 4%, A. salmonicida 2%, A. media 2%, A. allosaccharophila 1%, A. dhakensis 1% and Aeromonas spp. 4%. Twelve virulence genes were present in the following proportions—exu 96%, ser 93%, aer 87%, fla 83%, enolase 70%, ela 62%, act 54%, aexT 33%, lip 16%, dam 16%, alt 8% and ast 4%, and at least 2 of these genes were present in all 102 strains. The ascV, aexU and hlyA genes were not detected among the isolates. A. hydrophila was the main species containing virulence genes alt and ast either present alone or in combination. It is possible that different mechanisms may be used by each genospecies to demonstrate virulence. In summary, with the use of GCAT and rpoD genes, unambiguous identification of Aeromonas species is possible and provides valuable data on the phylogenetic diversity of the organism. PMID:26710336

  14. Phenotypic and Genetic Diversity of Aeromonas Species Isolated from Fresh Water Lakes in Malaysia.

    PubMed

    Khor, Wei Ching; Puah, Suat Moi; Tan, Jin Ai Mary Anne; Puthucheary, S D; Chua, Kek Heng

    2015-01-01

    Gram-negative bacilli of the genus Aeromonas are primarily inhabitants of the aquatic environment. Humans acquire this organism from a wide range of food and water sources as well as during aquatic recreational activities. In the present study, the diversity and distribution of Aeromonas species from freshwater lakes in Malaysia was investigated using glycerophospholipid-cholesterol acyltransferase (GCAT) and RNA polymerase sigma-factor (rpoD) genes for speciation. A total of 122 possible Aeromonas strains were isolated and confirmed to genus level using the API20E system. The clonality of the isolates was investigated using ERIC-PCR and 20 duplicate isolates were excluded from the study. The specific GCAT-PCR identified all isolates as belonging to the genus Aeromonas, in agreement with the biochemical identification. A phylogenetic tree was constructed using the rpoD gene sequence and all 102 isolates were identified as: A. veronii 43%, A. jandaei 37%, A. hydrophila 6%, A. caviae 4%, A. salmonicida 2%, A. media 2%, A. allosaccharophila 1%, A. dhakensis 1% and Aeromonas spp. 4%. Twelve virulence genes were present in the following proportions--exu 96%, ser 93%, aer 87%, fla 83%, enolase 70%, ela 62%, act 54%, aexT 33%, lip 16%, dam 16%, alt 8% and ast 4%, and at least 2 of these genes were present in all 102 strains. The ascV, aexU and hlyA genes were not detected among the isolates. A. hydrophila was the main species containing virulence genes alt and ast either present alone or in combination. It is possible that different mechanisms may be used by each genospecies to demonstrate virulence. In summary, with the use of GCAT and rpoD genes, unambiguous identification of Aeromonas species is possible and provides valuable data on the phylogenetic diversity of the organism.

  15. Aeromonas Caviae Strain Induces Th1 Cytokine Response in Mouse Intestinal Tract

    EPA Science Inventory

    Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus. Microarray profiling of murine small i...

  16. Insight into the mobilome of Aeromonas strains

    PubMed Central

    Piotrowska, Marta; Popowska, Magdalena

    2015-01-01

    The mobilome is a pool of genes located within mobile genetic elements (MGE), such as plasmids, IS elements, transposons, genomic/pathogenicity islands, and integron-associated gene cassettes. These genes are often referred to as “flexible” and may encode virulence factors, toxic compounds as well as resistance to antibiotics. The phenomenon of MGE transfer between bacteria, known as horizontal gene transfer (HGT), is well documented. The genes present on MGE are subject to continuous processes of evolution and environmental changes, largely induced or significantly accelerated by man. For bacteria, the only chance of survival in an environment contaminated with toxic chemicals, heavy metals and antibiotics is the acquisition of genes providing the ability to survive in such conditions. The process of acquiring and spreading antibiotic resistance genes (ARG) is of particular significance, as it is important for the health of humans and animals. Therefore, it is important to thoroughly study the mobilome of Aeromonas spp. that is widely distributed in various environments, causing many diseases in fishes and humans. This review discusses the recently published information on MGE prevalent in Aeromonas spp. with special emphasis on plasmids belonging to different incompatibility groups, i.e., IncA/C, IncU, IncQ, IncF, IncI, and ColE-type. The vast majority of plasmids carry a number of different transposons (Tn3, Tn21, Tn1213, Tn1721, Tn4401), the 1st, 2nd, or 3rd class of integrons, IS elements (e.g., IS26, ISPa12, ISPa13, ISKpn8, ISKpn6) and encode determinants such as antibiotic and mercury resistance genes, as well as virulence factors. Although the actual role of Aeromonas spp. as a human pathogen remains controversial, species of this genus may pose a serious risk to human health. This is due to the considerable potential of their mobilome, particularly in terms of antibiotic resistance and the possibility of the horizontal transfer of resistance genes

  17. Virulence potential and genetic diversity of Aeromonas caviae, Aeromonas veronii, and Aeromonas hydrophila clinical isolates from Mexico and Spain: a comparative study.

    PubMed

    Aguilera-Arreola, Ma Guadalupe; Hernández-Rodríguez, César; Zúñiga, Gerardo; Figueras, María José; Garduño, Rafael A; Castro-Escarpulli, Graciela

    2007-07-01

    A comparative study of 109 Aeromonas clinical isolates belonging to the 3 species most frequently isolated from patients with diarrhea in Mexico and Spain was performed to investigate the distribution of 3 prominent toxin genes and the gene encoding flagellin of lateral flagella; 4 well-established virulence factors in the genus Aeromonas. The aerolysin-hemolysin toxin genes were the most prevalent, being present in 89% of the total isolates. The ast toxin gene was conspicuously absent from the Aeromonas caviae and Aeromonas veronii groups but was present in 91% of the Aeromonas hydrophila isolates. Both the alt toxin gene and the lafA flagellin gene also had a low incidence in A. caviae and A. veronii. Differences in the prevalence of alt and lafA were observed between isolates from Mexico and Spain, confirming genus heterogeneity according to geographic location. Carriage of multiple toxin genes was primarily restricted to A. hydrophila isolates, suggesting that A. caviae and A. veronii isolates circulating in Mexico and Spain possess a limited array of virulence genes. Enterobacterial repetitive intergenetic consensus - polymerase chain reaction showed that the Aeromonas populations sampled lack dominant clones and were genetically heterogeneous, with A. caviae being the most diverse species. Further surveys of virulence determinants in genetically heterogeneous populations of Aeromonas isolates circulating worldwide are required to enhance the understanding of their capacity to cause disease.

  18. Virulence potential and genetic diversity of Aeromonas caviae, Aeromonas veronii, and Aeromonas hydrophila clinical isolates from Mexico and Spain: a comparative study.

    PubMed

    Aguilera-Arreola, Ma Guadalupe; Hernández-Rodríguez, César; Zúñiga, Gerardo; Figueras, María José; Garduño, Rafael A; Castro-Escarpulli, Graciela

    2007-07-01

    A comparative study of 109 Aeromonas clinical isolates belonging to the 3 species most frequently isolated from patients with diarrhea in Mexico and Spain was performed to investigate the distribution of 3 prominent toxin genes and the gene encoding flagellin of lateral flagella; 4 well-established virulence factors in the genus Aeromonas. The aerolysin-hemolysin toxin genes were the most prevalent, being present in 89% of the total isolates. The ast toxin gene was conspicuously absent from the Aeromonas caviae and Aeromonas veronii groups but was present in 91% of the Aeromonas hydrophila isolates. Both the alt toxin gene and the lafA flagellin gene also had a low incidence in A. caviae and A. veronii. Differences in the prevalence of alt and lafA were observed between isolates from Mexico and Spain, confirming genus heterogeneity according to geographic location. Carriage of multiple toxin genes was primarily restricted to A. hydrophila isolates, suggesting that A. caviae and A. veronii isolates circulating in Mexico and Spain possess a limited array of virulence genes. Enterobacterial repetitive intergenetic consensus - polymerase chain reaction showed that the Aeromonas populations sampled lack dominant clones and were genetically heterogeneous, with A. caviae being the most diverse species. Further surveys of virulence determinants in genetically heterogeneous populations of Aeromonas isolates circulating worldwide are required to enhance the understanding of their capacity to cause disease. PMID:17898843

  19. Differentiation of Aeromonas isolated from drinking water distribution systems using matrix-assisted laser desorption/ionization-mass spectrometry.

    PubMed

    Donohue, Maura J; Best, Jennifer M; Smallwood, Anthony W; Kostich, Mitchell; Rodgers, Mark; Shoemaker, Jody A

    2007-03-01

    The genus Aeromonas is one of several medically significant genera that have gained prominence due to their evolving taxonomy and controversial role in human diseases. In this study, matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to analyze the whole cells of both reference strains and unknown Aeromonas isolates obtained from water distribution systems. A library of over 45 unique m/z signatures was created from 40 strains that are representative of the 17 recognized species of Aeromonas, as well as 3 reference strains from genus Vibrio and 2 reference strains from Plesiomonas shigelloides. The library was used to help speciate 52 isolates of Aeromonas. The environmental isolates were broken up into 2 blind studies. Group 1 contained isolates that had a recognizable phenotypic profile and group 2 contained isolates that had an atypical phenotypic profile. MALDI-MS analysis of the water isolates in group 1 matched the phenotypic identification in all cases. In group 2, the MALDI-MS-based determination confirmed the identity of 18 of the 27 isolates. These results demonstrate that MALDI-MS analysis can rapidly and accurately classify species of the genus Aeromonas, making it a powerful tool especially suited for environmental monitoring and detection of microbial hazards in drinking water.

  20. Evaluation of different assay systems for identification of environmental Aeromonas strains.

    PubMed

    Toranzo, A E; Santos, Y; Nieto, T P; Barja, J L

    1986-03-01

    Important biochemical reactions in conventional tests were compared with counterpart reactions in two multiple test systems, API-20E (Analytab Products, Plainview, N.Y.) and Aeromonas hydrophila medium, to evaluate their accuracy for the identification of motile Aeromonas spp. isolated from fish. In a total of 49 Aeromonas spp. isolates and 10 A. hydrophila reference strains, false-negative or -positive reactions were detected in the Voges-Proskauer test, indole production, gelatinase activity, production of gas, fermentation of arabinose, and lysine decarboxylase reaction. A good correlation was found, among the three identification systems, for the fermentation of mannitol and inositol as well as for the arginine dihydrolase and ornithine decarboxylase tests. The failure of A. hydrophila medium in the detection of gas indicates that this medium is not entirely suitable for defining aerogenic or anaerogenic strains. From the results of the present study, we consider that of the identification method and taxonomic scheme to be adopted for environmental Aeromonas spp. must be standardized.

  1. Mutation in the S-ribosylhomocysteinase (luxS) gene involved in quorum sensing affects biofilm formation and virulence in a clinical isolate of Aeromonas hydrophila

    EPA Science Inventory

    A diarrheal isolate SSU of Aeromonas hydrophila produces a cytotoxic enterotoxin (Act) with cytotoxic, enterotoxic, and hemolytic activities. Our laboratory has characterized from the above Aeromonas strain, in addition to Act, the type 3- and T6-secretion systems and their effec...

  2. Multi-Drug Resistance Mediated by Class 1 Integrons in Aeromonas Isolated from Farmed Freshwater Animals

    PubMed Central

    Deng, Yuting; Wu, Yali; Jiang, Lan; Tan, Aiping; Zhang, Ruiquan; Luo, Li

    2016-01-01

    Aeromonas is regarded as an important pathogen of freshwater animals but little is known about the genetics of its antimicrobial resistance in Chinese aquaculture. The aim of this study was to investigate the presence of integrons and characterize multidrug resistant Aeromonas spp. isolated from diseased farmed freshwater animals. These animal samples included fish, ornamental fish, shrimp, turtles, and amphibians which were collected from 64 farms in Guangdong province of South China. One hundred and twelve Aeromonas spp. isolates were examined for antimicrobial resistance phenotypes and the presence of class 1 integron sequences. Twenty-two (19.6%) of these isolates carried a class 1 integron comprising six different gene insertion cassettes including drfA12-orfF-aadA2, drfA12-orfF, aac(6′)-II-blaOXA-21-cat3, catB3, arr-3, and dfrA17. Among these, drfA12-orfF-aadA2 was the dominant gene cassette array (63.6%, 14/22) and this is the first report of aac(6′)-II-blaOXA-21-cat3 in an Aeromonas hydrophila isolate from a Chinese giant salamander (Andrias davidianus). All the integron-positive strains were resistant to more than five agents and 22 contained other resistance genes including blaCTX-M-3, blaTEM-1, aac(6′)-Ib-cr, and tetA. All integron-positive isolates also contained mutations in the quinolone resistance determining regions (QRDR). Our investigation demonstrates that freshwater animals can serve as a reservoir for pathogenic Aeromonas strains containing multiple drug-resistance integrons. This data suggests that surveillance for antimicrobial resistance of animal origin and a prudent and responsible use of antimicrobials in aquaculture is necessary in these farms. PMID:27379065

  3. Multi-Drug Resistance Mediated by Class 1 Integrons in Aeromonas Isolated from Farmed Freshwater Animals.

    PubMed

    Deng, Yuting; Wu, Yali; Jiang, Lan; Tan, Aiping; Zhang, Ruiquan; Luo, Li

    2016-01-01

    Aeromonas is regarded as an important pathogen of freshwater animals but little is known about the genetics of its antimicrobial resistance in Chinese aquaculture. The aim of this study was to investigate the presence of integrons and characterize multidrug resistant Aeromonas spp. isolated from diseased farmed freshwater animals. These animal samples included fish, ornamental fish, shrimp, turtles, and amphibians which were collected from 64 farms in Guangdong province of South China. One hundred and twelve Aeromonas spp. isolates were examined for antimicrobial resistance phenotypes and the presence of class 1 integron sequences. Twenty-two (19.6%) of these isolates carried a class 1 integron comprising six different gene insertion cassettes including drfA12-orfF-aadA2, drfA12-orfF, aac(6')-II-bla OXA-21 -cat3, catB3, arr-3, and dfrA17. Among these, drfA12-orfF-aadA2 was the dominant gene cassette array (63.6%, 14/22) and this is the first report of aac(6')-II-bla OXA-21 -cat3 in an Aeromonas hydrophila isolate from a Chinese giant salamander (Andrias davidianus). All the integron-positive strains were resistant to more than five agents and 22 contained other resistance genes including bla CTX-M-3, bla TEM-1, aac(6')-Ib-cr, and tetA. All integron-positive isolates also contained mutations in the quinolone resistance determining regions (QRDR). Our investigation demonstrates that freshwater animals can serve as a reservoir for pathogenic Aeromonas strains containing multiple drug-resistance integrons. This data suggests that surveillance for antimicrobial resistance of animal origin and a prudent and responsible use of antimicrobials in aquaculture is necessary in these farms. PMID:27379065

  4. Analysis of antimicrobial resistance genes in Aeromonas spp. isolated from cultured freshwater animals in China.

    PubMed

    Deng, Yu-Ting; Wu, Ya-Li; Tan, Al-Ping; Huang, Yu-Ping; Jiang, Lan; Xue, Hui-Juan; Wang, Wei-Li; Luo, Li; Zhao, Fei

    2014-08-01

    The development of resistance to antimicrobials used in aquatic animals is an increasing concern for aquaculture and public health. To monitor the occurrence of antimicrobial resistance and resistance genes in Aeromonas, a total of 106 isolates were collected from cultured freshwater animals in China from 1995 to 2012. Antimicrobial susceptibilities were determined by the disk diffusion method. The highest resistance percentage occurred with ampicillin, rifampin, streptomycin, and nalidixic acid. Most strains were sensitive to fluoroquinolones, doxycycline, cefotaxime, chloramphenicol, and amikacin. The isolates from turtle samples had the highest levels of resistance to 11 of the 12 tested antimicrobials when compared with those from fish or shrimp. Polymerase chain reaction and DNA sequence results showed that all trimethoprim/sulfamethoxazole-resistant strains contained sul1, and 37.0% were positive for tetA in tetracycline-resistant strains. ant(3″)-Ia was identified in 13 (24.5%) streptomycin-resistant strains. Plasmid-borne quinolone resistance genes were detected in five Aeromonas hydrophila (4.7%), two of which carried qnrS2, while the other three strains harbored aac(6')-Ib-cr. Two cefotaxime-resistant A. hydrophila were positive for bla(TEM-1) and bla(CTX-M-3). To our knowledge, this is the first report characterizing antimicrobial resistance in Aeromonas isolated from cultured freshwater animals in China, and providing resistance information of pathogen in Chinese aquaculture.

  5. Chironomids' Relationship with Aeromonas Species.

    PubMed

    Laviad, Sivan; Halpern, Malka

    2016-01-01

    Chironomids (Diptera: Chironomidae), also known as non-biting midges, are one of the most abundant groups of insects in aquatic habitats. They undergo a complete metamorphosis of four life stages of which three are aquatic (egg, larva, and pupa), and the adult emerges into the air. Chironomids serve as a natural reservoir of Aeromonas and Vibrio cholerae species. Here, we review existing knowledge about the mutual relations between Aeromonas species and chironomids. Using 454-pyrosequencing of the 16S rRNA gene, we found that the prevalence of Aeromonas species in the insects' egg masses and larvae was 1.6 and 3.3% of the insects' endogenous microbiota, respectively. Aeromonas abundance per egg mass remained stable during a 6-month period of bacterial monitoring. Different Aeromonas species were isolated and some demonstrated the ability to degrade the insect's egg masses and to prevent eggs hatching. Chitinase was identified as the enzyme responsible for the egg mass degradation. Different Aeromonas species isolated from chironomids demonstrated the potential to protect their host from toxic metals. Aeromonas is a causative agent of fish infections. Fish are frequently recorded as feeding on chironomids. Thus, fish might be infected with Aeromonas species via chironomid consumption. Aeromonas strains are also responsible for causing gastroenteritis and wound infections in humans. Different virulence genes were identified in Aeromonas species isolated from chironomids. Chironomids may infest drinking water reservoirs, hence be the source of pathogenic Aeromonas strains in drinking water. Chironomids and Aeromonas species have a complicated mutual relationship. PMID:27242751

  6. Active Shiga-Like Toxin Produced by Some Aeromonas spp., Isolated in Mexico City

    PubMed Central

    Palma-Martínez, Ingrid; Guerrero-Mandujano, Andrea; Ruiz-Ruiz, Manuel J.; Hernández-Cortez, Cecilia; Molina-López, José; Bocanegra-García, Virgilio; Castro-Escarpulli, Graciela

    2016-01-01

    Shiga-like toxins (Stx) represent a group of bacterial toxins involved in human and animal diseases. Stx is produced by enterohemorrhagic Escherichia coli, Shigella dysenteriae type 1, Citrobacter freundii, and Aeromonas spp.; Stx is an important cause of bloody diarrhea and hemolytic uremic syndrome (HUS). The aim of this study was to identify the stx1/stx2 genes in clinical strains and outer membrane vesicles (OMVs) of Aeromonas spp., 66 strains were isolated from children who live in Mexico City, and Stx effects were evaluated in Vero cell cultures. The capacity to express active Stx1 and Stx2 toxins was determined in Vero cell cultures and the concentration of Stx was evaluated by 50% lethal dose (LD50) assays, observing inhibition of damaged cells by specific monoclonal antibodies. The results obtained in this study support the hypothesis that the stx gene is another putative virulence factor of Aeromonas, and since this gene can be transferred horizontally through OMVs this genus should be included as a possible causal agents of gastroenteritis and it should be reported as part of standard health surveillance procedures. Furthermore, these results indicate that the Aeromonas genus might be a potential causative agent of HUS. PMID:27725813

  7. Functional genomic characterization of virulence factors from necrotizing fasciitis-causing strains of Aeromonas hydrophila.

    PubMed

    Grim, Christopher J; Kozlova, Elena V; Ponnusamy, Duraisamy; Fitts, Eric C; Sha, Jian; Kirtley, Michelle L; van Lier, Christina J; Tiner, Bethany L; Erova, Tatiana E; Joseph, Sandeep J; Read, Timothy D; Shak, Joshua R; Joseph, Sam W; Singletary, Ed; Felland, Tracy; Baze, Wallace B; Horneman, Amy J; Chopra, Ashok K

    2014-07-01

    The genomes of 10 Aeromonas isolates identified and designated Aeromonas hydrophila WI, Riv3, and NF1 to NF4; A. dhakensis SSU; A. jandaei Riv2; and A. caviae NM22 and NM33 were sequenced and annotated. Isolates NF1 to NF4 were from a patient with necrotizing fasciitis (NF). Two environmental isolates (Riv2 and -3) were from the river water from which the NF patient acquired the infection. While isolates NF2 to NF4 were clonal, NF1 was genetically distinct. Outside the conserved core genomes of these 10 isolates, several unique genomic features were identified. The most virulent strains possessed one of the following four virulence factors or a combination of them: cytotoxic enterotoxin, exotoxin A, and type 3 and 6 secretion system effectors AexU and Hcp. In a septicemic-mouse model, SSU, NF1, and Riv2 were the most virulent, while NF2 was moderately virulent. These data correlated with high motility and biofilm formation by the former three isolates. Conversely, in a mouse model of intramuscular infection, NF2 was much more virulent than NF1. Isolates NF2, SSU, and Riv2 disseminated in high numbers from the muscular tissue to the visceral organs of mice, while NF1 reached the liver and spleen in relatively lower numbers on the basis of colony counting and tracking of bioluminescent strains in real time by in vivo imaging. Histopathologically, degeneration of myofibers with significant infiltration of polymorphonuclear cells due to the highly virulent strains was noted. Functional genomic analysis provided data that allowed us to correlate the highly infectious nature of Aeromonas pathotypes belonging to several different species with virulence signatures and their potential ability to cause NF.

  8. Functional Genomic Characterization of Virulence Factors from Necrotizing Fasciitis-Causing Strains of Aeromonas hydrophila

    PubMed Central

    Grim, Christopher J.; Kozlova, Elena V.; Ponnusamy, Duraisamy; Fitts, Eric C.; Sha, Jian; Kirtley, Michelle L.; van Lier, Christina J.; Tiner, Bethany L.; Erova, Tatiana E.; Joseph, Sandeep J.; Read, Timothy D.; Shak, Joshua R.; Joseph, Sam W.; Singletary, Ed; Felland, Tracy; Baze, Wallace B.; Horneman, Amy J.

    2014-01-01

    The genomes of 10 Aeromonas isolates identified and designated Aeromonas hydrophila WI, Riv3, and NF1 to NF4; A. dhakensis SSU; A. jandaei Riv2; and A. caviae NM22 and NM33 were sequenced and annotated. Isolates NF1 to NF4 were from a patient with necrotizing fasciitis (NF). Two environmental isolates (Riv2 and -3) were from the river water from which the NF patient acquired the infection. While isolates NF2 to NF4 were clonal, NF1 was genetically distinct. Outside the conserved core genomes of these 10 isolates, several unique genomic features were identified. The most virulent strains possessed one of the following four virulence factors or a combination of them: cytotoxic enterotoxin, exotoxin A, and type 3 and 6 secretion system effectors AexU and Hcp. In a septicemic-mouse model, SSU, NF1, and Riv2 were the most virulent, while NF2 was moderately virulent. These data correlated with high motility and biofilm formation by the former three isolates. Conversely, in a mouse model of intramuscular infection, NF2 was much more virulent than NF1. Isolates NF2, SSU, and Riv2 disseminated in high numbers from the muscular tissue to the visceral organs of mice, while NF1 reached the liver and spleen in relatively lower numbers on the basis of colony counting and tracking of bioluminescent strains in real time by in vivo imaging. Histopathologically, degeneration of myofibers with significant infiltration of polymorphonuclear cells due to the highly virulent strains was noted. Functional genomic analysis provided data that allowed us to correlate the highly infectious nature of Aeromonas pathotypes belonging to several different species with virulence signatures and their potential ability to cause NF. PMID:24795370

  9. [Detection of the first QnrS gene positivity in aquatic Aeromonas spp. isolates in Turkey].

    PubMed

    Onuk, Ertan Emek; Tanrıverdi Çaycı, Yeliz; Çoban, Ahmet Yılmaz; Çiftci, Alper; Balta, Fikri; Didinen, Behire Işıl; Pekmezci, Gökmen Zafer; Altun, Soner; Söğüt Ünlü, Mehtap; Deveci, Aydın

    2015-01-01

    Aeromonas spp. are oxidase positive, gram-negative, facultative anaerobic bacilli that are widely distributed in aquatic environments. A.hydrophila, A.sobria and A.bestiarum may cause severe infections in both human and cold-blooded animals. Environmental persistance of quinolones that are widely used in both human and veterinary medicine plays an important role in the selection of resistant mutants. Plasmid-mediated resistance is one of the main mechanisms involved in quinolone resistance, and qnr, qepA, aac(6')-Ib-cr, oqxAB genes are identified as resistance determinants. Determination of various types of qnr gene in different bacteria mainly in Enterobacteriaceae, suggests that they are widely distributed in nature. Recently, plasmid-mediated quinolone resistance was defined among Aeromonas species isolated from water. The aim of this study was to investigate the presence of qnr genes among aquatic Aeromonas spp. in Turkey. A total of 45 Aeromonas strains isolated from water and fishes collected from three different geographical regions (Aegean, Mediterranean and Blacksea) in Turkey, were included in the study. The isolates were identified at species level by the use of 16S rDNA-RFLP (Restriction fragment length polymorphism) analysis and multiplex polymerase chain reaction (M-PCR). Among the isolates, 20 were identified as A.sobria, 10 as A.hydrophila, nine as A.salmonicida, four as A.bestiarum and two as A.veronii. The plasmid-mediated quinolone resistance determinants, qnrA, qnrB, qnrC and qnrS genes, were investigated by M-PCR, and sequence analysis was performed for nine qnr-positive isolates. According to the sequence analysis of the genes, qnr genes were characterized in six A.sobria, in two A.bestiarum and in one A.hydrophila isolate (9/45; 20%). When the sequence was compared with GenBank database, this gene was found as qnrS2. All qnrS-positive Aeromonas spp. isolates were ciprofloxacin-susceptible, while five of them were resistant to nalidixic acid

  10. Characterization of Virulence Properties of Aeromonas veronii Isolated from Diseased Gibel Carp (Carassius gibelio).

    PubMed

    Sun, Jingjing; Zhang, Xiaojun; Gao, Xiaojian; Jiang, Qun; Wen, Yi; Lin, Li

    2016-01-01

    Aeromonas veronii is a kind of opportunistic pathogen to fish and humans, significantly impending aquaculture production. Recently, we isolated two A. veronii strains, named GYC1 and GYC2, from diseased Gibel carp (Carassius gibelio) in China. Based on gyrB (DNA gyrase B subunit) genes of GYC1 and GYC2, the constructed phylogenetic tree showed that the two strains were clustered with A. veronii. Sixteen virulence genes related to the pathogenicity of Aeromonas spp. were subjected to PCR assay. The genes of ompAI, ompAII, lafA, act, aer, fla, gcaT and acg were detected in the two strains, while genes of hly, ahp, lip, ast and alt were not detected. Additionally, genes eprCAI, ela and exu were only detected in the strain GYC1. Furthermore, the results of extracellular enzyme analysis revealed that the two isolates can produce hemolysin, caseinase, esterase, amylase and lecithinase, which were closely related to the pathogenicity of the two strains. However, the results showed that there was no gelatinase activity in either strain. According to the antibiotic resistant assay, the two strains were sensitive to cephalosporins and aminoglycosides, while they were resistant to penicillins and quinolones. Through this study, the virulence characteristics, including virulence genes and extracellular enzymes, the pathogenicity of A. veronii was clarified, enhancing the understanding about this pathogenic bacterium and providing the theoretical basis in disease control. PMID:27043558

  11. Characterization of Virulence Properties of Aeromonas veronii Isolated from Diseased Gibel Carp (Carassius gibelio)

    PubMed Central

    Sun, Jingjing; Zhang, Xiaojun; Gao, Xiaojian; Jiang, Qun; Wen, Yi; Lin, Li

    2016-01-01

    Aeromonas veronii is a kind of opportunistic pathogen to fish and humans, significantly impending aquaculture production. Recently, we isolated two A. veronii strains, named GYC1 and GYC2, from diseased Gibel carp (Carassius gibelio) in China. Based on gyrB (DNA gyrase B subunit) genes of GYC1 and GYC2, the constructed phylogenetic tree showed that the two strains were clustered with A. veronii. Sixteen virulence genes related to the pathogenicity of Aeromonas spp. were subjected to PCR assay. The genes of ompAI, ompAII, lafA, act, aer, fla, gcaT and acg were detected in the two strains, while genes of hly, ahp, lip, ast and alt were not detected. Additionally, genes eprCAI, ela and exu were only detected in the strain GYC1. Furthermore, the results of extracellular enzyme analysis revealed that the two isolates can produce hemolysin, caseinase, esterase, amylase and lecithinase, which were closely related to the pathogenicity of the two strains. However, the results showed that there was no gelatinase activity in either strain. According to the antibiotic resistant assay, the two strains were sensitive to cephalosporins and aminoglycosides, while they were resistant to penicillins and quinolones. Through this study, the virulence characteristics, including virulence genes and extracellular enzymes, the pathogenicity of A. veronii was clarified, enhancing the understanding about this pathogenic bacterium and providing the theoretical basis in disease control. PMID:27043558

  12. Antibiogram characterization and putative virulence genes in Aeromonas species isolated from pig fecal samples.

    PubMed

    Igbinosa, Isoken H; Igbinosa, Etinosa O; Okoh, Anthony I

    2016-06-01

    Aeromonas species are broadly distributed in nature and agricultural environments and have been isolated from feces, bedding, and drinking water of healthy pigs. We assessed the incidence, virulence properties, and antimicrobial resistance profile of Aeromonas spp., isolated from pig feces. Antibiogram was done using the disc diffusion methods, and polymerase chain reaction was used for the detection of putative virulence genes. Identification of isolates revealed three phenotypic species with percentage distribution as follows: Aeromonas hydrophila 23 (45.1 %), Aeromonas caviae 16 (31.4 %), and Aeromonas sobria 12 (23.5 %). All Aeromonas isolates in the study were absolutely susceptible to cefotaxime and resistant to penicillin. A. cavaie and A. sobria demonstrated absolute susceptibility against ciprofloxacin and streptomycin. Aeromonas species showed varied susceptibility to cephalothin as follows: A. hydrophila 78.3 %, A. cavaie 93.7 %, and A. sobria 91.7 %. The percentage distribution of virulence genes among Aeromonas isolates were as follows: Aerolysin (aer) 74.5 %, flagellin gene (fla) 68.6 %, cytotoxin (hly A) 43.1 %, lipase (lip) 39.2 %, enterotoxic activities (ast) 31.3 %, and cytotonic gene (alt) 13.7 %. Reports from this study shows that Aeromonas species isolated from pig fecal samples are multi-drug resistant and possess virulence potential which may result to possible risk of human or animal infection and likely contamination of food and water from this sources.

  13. Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract

    EPA Science Inventory

    Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus,. Microarray profiling of...

  14. Whole-Genome Sequence of Aeromonas hydrophila Strain AH-1 (Serotype O11)

    PubMed Central

    Forn-Cuní, Gabriel; Tomás, Juan M.

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of aquatic and terrestrial animals, including humans. Here, we report the whole-genome sequence of the septicemic A. hydrophila AH-1 strain, belonging to the serotype O11, and the first mesophilic Aeromonas with surface layer (S-layer) to be sequenced. PMID:27587829

  15. Whole-Genome Sequence of Aeromonas hydrophila Strain AH-1 (Serotype O11).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-09-01

    Aeromonas hydrophila is an emerging pathogen of aquatic and terrestrial animals, including humans. Here, we report the whole-genome sequence of the septicemic A. hydrophila AH-1 strain, belonging to the serotype O11, and the first mesophilic Aeromonas with surface layer (S-layer) to be sequenced.

  16. Whole-Genome Sequence of Aeromonas hydrophila Strain AH-1 (Serotype O11).

    PubMed

    Forn-Cuní, Gabriel; Tomás, Juan M; Merino, Susana

    2016-01-01

    Aeromonas hydrophila is an emerging pathogen of aquatic and terrestrial animals, including humans. Here, we report the whole-genome sequence of the septicemic A. hydrophila AH-1 strain, belonging to the serotype O11, and the first mesophilic Aeromonas with surface layer (S-layer) to be sequenced. PMID:27587829

  17. A study on genetic variability of pathogenic Aeromonas hydrophila strains and the varied responses of the strains towards phyto-extracts.

    PubMed

    Balasundaram, A; Kumari, P Rathna; Kolanchinathan, P; Masilamani, V; John, George

    2013-11-01

    The present study evaluated genetic variation in Aeromonas hydrophila strains using PCR-RAPD and their varied susceptibility to phyto-extract. Four strains of Aeromonas hydrophila isolated from skin infections of common freshwater fish, Cyprinus carpio were characterized by various biochemical methods, physiological tests and PCR- RAPD. Antimicrobial activity of the leaf extracts of three medicinal plants, Ocimum sanctum, Adathoda vasica and Calendula officinalis were tested against the four strains of A. hydrophila by disc diffusion (Kirby-Bauer) method. Antagonistic effects of leaf extracts against A. hydrophila strains were assessed by co-culture method. RAPD analysis showed that all the microbes isolated from skin infection belong to the same species but there was no 100% genetic similarity among them Dendrogram constructed by UPGMA clearly supported the PCR pattern of genetic variability among the strains. This study revealed that Aeromonas hydophila exhibits genetic variability and varied susceptibility towards phyto-extracts. Results indicated that phyto-extracts offers a promising alternative to the use of antibiotics in controlling Aeromonas hydrophila. PMID:24511738

  18. A study on genetic variability of pathogenic Aeromonas hydrophila strains and the varied responses of the strains towards phyto-extracts.

    PubMed

    Balasundaram, A; Kumari, P Rathna; Kolanchinathan, P; Masilamani, V; John, George

    2013-11-01

    The present study evaluated genetic variation in Aeromonas hydrophila strains using PCR-RAPD and their varied susceptibility to phyto-extract. Four strains of Aeromonas hydrophila isolated from skin infections of common freshwater fish, Cyprinus carpio were characterized by various biochemical methods, physiological tests and PCR- RAPD. Antimicrobial activity of the leaf extracts of three medicinal plants, Ocimum sanctum, Adathoda vasica and Calendula officinalis were tested against the four strains of A. hydrophila by disc diffusion (Kirby-Bauer) method. Antagonistic effects of leaf extracts against A. hydrophila strains were assessed by co-culture method. RAPD analysis showed that all the microbes isolated from skin infection belong to the same species but there was no 100% genetic similarity among them Dendrogram constructed by UPGMA clearly supported the PCR pattern of genetic variability among the strains. This study revealed that Aeromonas hydophila exhibits genetic variability and varied susceptibility towards phyto-extracts. Results indicated that phyto-extracts offers a promising alternative to the use of antibiotics in controlling Aeromonas hydrophila.

  19. Prevalence and characteristics of Aeromonas species isolated from processed channel catfish.

    PubMed

    Wang, C; Silva, J L

    1999-01-01

    From August 1994 to May 1995, 238 channel catfish fillets collected from three processing plants in the Mississippi Delta at four time periods were tested for the presence of Aeromonas species. Identification of Aeromonas spp. was accomplished using an automated Vitek bioassay system with gram-negative and nonfermenter cards. Approximately 36.1% were positive for A. hydrophila, 35.7% for A. sobria, and 10.9% for A. caviae. All three Aeromonas spp. were found in all three processing plants, and the incidence of A. hydrophila contamination appeared to be higher in summer than other seasons. Eighty-six percent of the Aeromonas isolates were hemolytic on 5% sheep blood agar plates. Most isolates were susceptible to chloramphenicol, neomycin, streptomycin, and trimethoprim-sulfamethoxazole and resistant to ampicillin and bacitracin. Results suggest that Aeromonas spp. are prevalent in processed channel catfish, and most isolates are hemolytic and resistant to ampicillin and bacitracin. PMID:9921825

  20. Complete genome sequence of channel catfish epidemic isolate Aeromonas hydrophila ML09-119

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila is a Gram-negative, rod-shaped, mesophilic bacteria that infects both aquatic poikilothermic animals and mammals, including humans. Here, we present the complete genome sequence of Aeromonas hydrophila ML-09-119, which represents a clonal group of A. hydrophila isolates causing ...

  1. Molecular and Chemical Analysis of the Lipopolysaccharide from Aeromonas hydrophila Strain AH-1 (Serotype O11)

    PubMed Central

    Merino, Susana; Canals, Rocío; Knirel, Yuriy A.; Tomás, Juan M.

    2015-01-01

    A group of virulent Aeromonas hydrophila, A. sobria, and A. veronii biovar sobria strains isolated from humans and fish have been described; these strains classified to serotype O11 are serologically related by their lipopolysaccharide (LPS) O-antigen (O-polysaccharide), and the presence of an S-layer consisting of multiple copies of a crystalline surface array protein with a molecular weight of 52 kDa in the form of a crystalline surface array which lies peripheral to the cell wall. A. hydrophila strain AH-1 is one of them. We isolated the LPS from this strain and determined the structure of the O-polysaccharide, which was similar to that previously described for another strain of serotype O11. The genetics of the O11-antigen showed the genes (wbO11 cluster) in two sections separated by genes involved in biosynthesis and assembly of the S-layer. The O11-antigen LPS is an example of an ABC-2-transporter-dependent pathway for O-antigen heteropolysaccharide (disaccharide) assembly. The genes involved in the biosynthesis of the LPS core (waaO11 cluster) were also identified in three different chromosome regions being nearly identical to the ones described for A. hydrophila AH-3 (serotype O34). The genetic data and preliminary chemical analysis indicated that the LPS core for strain AH-1 is identical to the one for strain AH-3. PMID:25874921

  2. Determination of microbial diversity of Aeromonas strains on the basis of multilocus sequence typing, phenotype, and presence of putative virulence genes.

    PubMed

    Martino, Maria Elena; Fasolato, Luca; Montemurro, Filomena; Rosteghin, Marina; Manfrin, Amedeo; Patarnello, Tomaso; Novelli, Enrico; Cardazzo, Barbara

    2011-07-01

    The genus Aeromonas has been described as comprising several species associated with the aquatic environment, which represents their principal reservoir. Aeromonas spp. are commonly isolated from diseased and healthy fish, but the involvement of such bacteria in human infection and gastroenteritis has frequently been reported. The primary challenge in establishing an unequivocal link between the Aeromonas genus and pathogenesis in humans is the extremely complicated taxonomy. With the aim of clarifying taxonomic relationships among the strains and phenotypes, a multilocus sequencing approach was developed and applied to characterize 23 type and reference strains of Aeromonas spp. and a collection of 77 field strains isolated from fish, crustaceans, and mollusks. All strains were also screened for putative determinants of virulence by PCR (ast, ahh1, act, asa1, eno, ascV, and aexT) and the production of acylated homoserine lactones (AHLs). In addition, the phenotypic fingerprinting obtained from 29 biochemical tests was submitted to the nonparametric combination (NPC) test methodology to define the statistical differences among the identified genetic clusters. Multilocus sequence typing (MLST) achieved precise strain genotyping, and the phylogenetic analysis of concatenated sequences delineated the relationship among the taxa belonging to the genus Aeromonas, providing a powerful tool for outbreak traceability, host range diffusion, and ecological studies. The NPC test showed the feasibility of phenotypic differentiation among the majority of the MLST clusters by using a selection of tests or the entire biochemical fingerprinting. A Web-based MLST sequence database (http://pubmlst.org/aeromonas) specific for the Aeromonas genus was developed and implemented with all the results.

  3. Chironomids’ Relationship with Aeromonas Species

    PubMed Central

    Laviad, Sivan; Halpern, Malka

    2016-01-01

    Chironomids (Diptera: Chironomidae), also known as non-biting midges, are one of the most abundant groups of insects in aquatic habitats. They undergo a complete metamorphosis of four life stages of which three are aquatic (egg, larva, and pupa), and the adult emerges into the air. Chironomids serve as a natural reservoir of Aeromonas and Vibrio cholerae species. Here, we review existing knowledge about the mutual relations between Aeromonas species and chironomids. Using 454-pyrosequencing of the 16S rRNA gene, we found that the prevalence of Aeromonas species in the insects’ egg masses and larvae was 1.6 and 3.3% of the insects’ endogenous microbiota, respectively. Aeromonas abundance per egg mass remained stable during a 6-month period of bacterial monitoring. Different Aeromonas species were isolated and some demonstrated the ability to degrade the insect’s egg masses and to prevent eggs hatching. Chitinase was identified as the enzyme responsible for the egg mass degradation. Different Aeromonas species isolated from chironomids demonstrated the potential to protect their host from toxic metals. Aeromonas is a causative agent of fish infections. Fish are frequently recorded as feeding on chironomids. Thus, fish might be infected with Aeromonas species via chironomid consumption. Aeromonas strains are also responsible for causing gastroenteritis and wound infections in humans. Different virulence genes were identified in Aeromonas species isolated from chironomids. Chironomids may infest drinking water reservoirs, hence be the source of pathogenic Aeromonas strains in drinking water. Chironomids and Aeromonas species have a complicated mutual relationship. PMID:27242751

  4. Cylindrospermopsin Biodegradation Abilities of Aeromonas sp. Isolated from Rusałka Lake

    PubMed Central

    Dziga, Dariusz; Kokocinski, Mikolaj; Maksylewicz, Anna; Czaja-Prokop, Urszula; Barylski, Jakub

    2016-01-01

    The occurrence of the cyanobacterial toxin cylindrospermopsin (CYN) in freshwater reservoirs is a common phenomenon. However, the biodegradation of this toxin in environmental samples has been observed only occasionally. In this work the biodegradation ability of cylindrospermopsin was investigated based on isolates from lakes with previous cyanotoxin history. Bacterial strains were identified based on the 16S rDNA and rpoD gene comparison. CYN biodegradation was monitored using the HPLC method. The R6 strain identified as Aeromonas sp. was documented as being capable of CYN removal. This biodegradation was dependent on the pH and temperature. Additionally, the stimulation of the growth of the R6 strain in the presence of CYN was indicated. Our discovery supports the hypothesis that (in analogy to the well-known phenomenon of microcystin biodegradation) in lakes dominated by potential CYN-producing cyanobacteria, the processes of microbial utilization of this toxin may occur. PMID:26927173

  5. Aeromonas hydrophila subsp. dhakensis isolated from feces, water and fish in Mediterranean Spain.

    PubMed

    Esteve, Consuelo; Alcaide, Elena; Blasco, María Dolores

    2012-01-01

    Eight Aeromonas hydrophila-like arabinose-negative isolates from diverse sources (i.e., river freshwater, cooling-system water pond, diseased wild European eels, and human stools) sampled in Valencia (Spain) during 2004-2005, were characterized by 16S rRNA gene sequencing and extensive biochemical testing along with reference strains of most Aeromonas species. These isolates and all reference strains of A. hydrophila subsp. dhakensis and A. aquariorum showed a 16S rRNA sequence similarity of 99.8-100%, and they all shared an identical phenotype. This matched exactly with that of A. hydrophila subsp. dhakensis since all strains displayed positive responses to the Voges-Prokauer test and to the use of dl-lactate. This is the first report of A. hydrophila subsp. dhakensis recovered from environmental samples, and further, from its original isolation in India during 1993-1994. This was accurately identified and segregated from other clinical aeromonads (A. hydrophila subsp. hydrophila, A. caviae, A. veronii biovars veronii and sobria, A. trota, A. schubertii and A. jandaei) by using biochemical key tests. The API 20 E profile for all strains included in A. hydrophila subsp. dhakensis was 7047125. The prevalence of this species in Spanish sources was higher for water (9.4%) than for feces (6%) or eels (1.3%). Isolates recovered as pure cultures from diseased eels were moderately virulent (LD(50) of 3.3×10(6) CFU fish(-1)) to challenged eels in experimental trials. They were all resistant to ticarcillin, amoxicillin-clavuranic acid, cefoxitin, and imipenem, regardless of its source. Our data point to A. hydrophila subsp. dhakensis as an emerging pathogen for humans and fish in temperate countries. PMID:22472298

  6. Aeromonas hydrophila subsp. dhakensis Isolated from Feces, Water and Fish in Mediterranean Spain

    PubMed Central

    Esteve, Consuelo; Alcaide, Elena; Blasco, María Dolores

    2012-01-01

    Eight Aeromonas hydrophila-like arabinose-negative isolates from diverse sources (i.e., river freshwater, cooling-system water pond, diseased wild European eels, and human stools) sampled in Valencia (Spain) during 2004–2005, were characterized by 16S rRNA gene sequencing and extensive biochemical testing along with reference strains of most Aeromonas species. These isolates and all reference strains of A. hydrophila subsp. dhakensis and A. aquariorum showed a 16S rRNA sequence similarity of 99.8–100%, and they all shared an identical phenotype. This matched exactly with that of A. hydrophila subsp. dhakensis since all strains displayed positive responses to the Voges-Prokauer test and to the use of dl-lactate. This is the first report of A. hydrophila subsp. dhakensis recovered from environmental samples, and further, from its original isolation in India during 1993–1994. This was accurately identified and segregated from other clinical aeromonads (A. hydrophila subsp. hydrophila, A. caviae, A. veronii biovars veronii and sobria, A. trota, A. schubertii and A. jandaei) by using biochemical key tests. The API 20 E profile for all strains included in A. hydrophila subsp. dhakensis was 7047125. The prevalence of this species in Spanish sources was higher for water (9.4%) than for feces (6%) or eels (1.3%). Isolates recovered as pure cultures from diseased eels were moderately virulent (LD50 of 3.3×106 CFU fish−1) to challenged eels in experimental trials. They were all resistant to ticarcillin, amoxicillin-clavuranic acid, cefoxitin, and imipenem, regardless of its source. Our data point to A. hydrophila subsp. dhakensis as an emerging pathogen for humans and fish in temperate countries. PMID:22472298

  7. Infection of sea lamprey with an unusual strain of Aeromonas salmonicida

    USGS Publications Warehouse

    Diamanka, Arfang; Loch, Thomas P.; Cipriano, Rocco C.; Winters, Andrew D.; Faisal, Mohamed

    2014-01-01

    The invasion of the Laurentian Great Lakes by the fish-parasitic sea lamprey has led to catastrophic consequences, including the potential introduction of fish pathogens. Aeromonas salmonicida is a bacterial fish pathogen that causes devastating losses worldwide. Currently, there are five accepted subspecies of Aeromonas salmonicida: A. salmonicida subsp. salmonicida, masoucida, smithia, achromogenes, and pectinolytica. We discuss the discovery of an isolate of A. salmonicida that is pathogenic to rainbow trout (Oncorhynchus mykiss) and exhibits unique phenotypic and molecular characteristics. We examined 181 adult sea lamprey (Petromyzon marinus) from the Humber River (Lake Ontario watershed) and 162 adult sea lamprey from Duffins Creek (Lake Ontario watershed) during the spring seasons of 2005–11. Among those, 4/343 (1.2%) sea lamprey were culture positive for A. salmonicida, whereby biochemical and molecular studies identified three of the isolates as A. salmonicida subsp. salmonicida. The remaining isolate (As-SL1) recovered from Humber River sea lamprey was phenotypically more similar to A. salmonicida subsp. salmonicida than to the four other A. salmonicida subspecies. However, unlike A. salmonicida subsp. salmonicida, As-SL1 was sucrose positive, produced an acid-over-acid reaction on triple-sugar iron medium and did not amplify with A. salmonicida subsp. salmonicida specific primers. Phylogenetic analysis based on partial stretches of the 16S rRNA and DNA gyrase subunit B genes further confirmed that the As-SL1 isolate was not A. salmonicida subsp. masoucida, smithia, achromogenes, or pectinolytica. Based on our analyses, the As-SL1 isolate is either an unusual strain of A. salmonicida subsp. salmonicida or a novel A. salmonicida subspecies. The four A. salmonicida isolates that were recovered from sea lamprey were pathogenic to rainbow trout in experimental challenge studies. Our study also underscores the potential role of sea lamprey in the ecology of

  8. Distribution of virulence genes in clinical and environmental isolates of Aeromonas spp.

    PubMed

    Chacón, M R; Figueras, M J; Castro-Escarpulli, G; Soler, L; Guarro, J

    2003-01-01

    The distribution and phenotypic activity of the genes encoding for serine protease, glycerophospholipid-cholesterol acyltransferase, lipases, aerolysin/hemolysin and DNases were investigated in 234 isolates identified by 16S rDNA-RFLP representing all the species of Aeromonas. The former three genes were found to be highly conserved among the genus. Aerolysin/hemolysin and DNase genes and beta-hemolytic activity were significantly more frequent in clinical than in environmental isolates. Aerolysin/hemolysin and serine protease genes were present in all beta-hemolytic strains supporting serine protease as possibly important for the activation of the former gene. The high prevalence of virulence factors in clinical isolates indicates that they may play a role in the mechanisms of pathogenesis of these microorganisms.

  9. Lysing activity of an indigenous algicidal bacterium Aeromonas sp. against Microcystis spp. isolated from Lake Taihu.

    PubMed

    Yang, Fei; Li, Xiaoqin; Li, Yunhui; Wei, Haiyan; Yu, Guang; Yin, Lihong; Liang, Geyu; Pu, Yuepu

    2013-01-01

    This study aimed to isolate and characterize an indigenous algicidal bacterium named LTH-1 and its algae-lysing compounds active against three Microcystis aeruginosa strains (toxic TH1, nontoxic TH2 and standard FACHB 905). The LTH-1 isolated from Lake Taihu, near Wuxi City in China, was identified as Aeromonas sp. based on its morphological characteristic features and phylogenetic analysis by sequencing of 16S rDNA. Extracellular compounds produced by LTH-1 showed strong algaelysing activity, and they were water-soluble and heat-tolerant, with a molecular mass lower than 2 kDa. Two algae-lysing compounds were isolated and purified from extracellular filtrate using silica gel column chromatography. One of these was identified as phenylalanine (C9H11NO2, m/z 166.0862) and the other (C8H16N2O3, m/z 189.1232) was unidentified by hybrid ion trap/time-of-flight mass spectrometry coupled with a high-performance liquid chromatography (LC/MS-IT-TOF) system. The half maximal effective concentration (EC50) of phenylalanine produced by LTH-1 against FACHB 905 was 68.2 +/- 8.2 microg mL(-1) in 48h. These results suggest that the algicidal Aeromonas sp. LTH-1 could play a role in controlling Microcystis blooms, and its extracellular compounds are also potentially useful for regulating blooms of the harmful M. aeruginosa. PMID:24191475

  10. IDENTIFICATION AND CHARACTERIZATION OF AEROMONAS ISOLATES FROM DRINKING WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    Members of the bacterial genus Aeromonas are commonly isolated from both fresh and salt waters worldwide and some are believed to cause infections in humans, including gastroenteritis and wound infections. Currently, aeromonads are on the United States Environmental Protection A...

  11. The incidence of virulence factors in mesophilic Aeromonas species isolated from farm animals and their environment.

    PubMed Central

    Gray, S. J.; Stickler, D. J.; Bryant, T. N.

    1990-01-01

    Sixty-one isolates of Aeromonas spp. from the faeces of pigs, cows and a variety of associated environmental sources were examined for the characteristics that are reputed to have roles in pathogenicity. Most isolates of Aeromonas hydrophila were cytotoxic (96.4%) and were capable of producing cell elongation factor (75%) and haemagglutinins (67.9%). In contrast few of the Aeromonas caviae isolates produced these three markers (13.6%, 27.3% and 36.4% respectively). In general, Aeromonas sobria occupied an intermediate position (36.4%, 27.3% and 54.5%), but they did produce the highest mean invasion index for HEp-2 cells. Statistical analysis revealed significant associations between the carriage of these factors and it was clear that many isolates of aeromonads from water and animals possessed the full battery of putative virulence factors. PMID:2209733

  12. Antimicrobial Resistance and Plasmid Profile of Bacterial Strains Isolated from the Urbanized Eltsovka-1 River (Russia).

    PubMed

    Lobova, Tatiana I; Yemelyanova, Elena; Andreeva, Irina S; Puchkova, Larisa I; Repin, Vladimir Ye

    2015-08-01

    Antimicrobial resistance and plasmid profile of Gram-positive and Gram-negative bacterial strains isolated from the urbanized Eltsovka-1 River (Russia) were investigated. Sequencing of the 16S rRNA of of G+ strains showed 99-100% identity to that of Bacillus aerophilus, Bacillus altitudinis, Bacillus amyloliquefaciens, Bacillus anthrancis, Bacillus barbaricus, Bacillus cereus, Bacillus flexus, Bacillus indriensis, Bacillus stratosphericus, Bacillus subtilis subsp. subtilis, Bacillus thuringiensis, Streptomyces albidoflavus, Streptomyces albus, Streptomyces exfoliatus, Streptomyces odorifer, and Streptomyces sampsonii. Sequencing of the 16S rRNA of G-strains was similar in 99-100% to that of Aeromonas bestiarum, Aeromonas encheleia, Aeromonas hydrophila, A. hydrophila subsp. anaerogenes, A. hydrophila subsp. dhakensis, Aeromonas media, Aeromonas molluscorum, Aeromonas popoffii, Aeromonas salmonicida subsp. masoucida, A. salmonicida subsp. pectinolytica, A. salmonicida subsp. salmonicida, Aeromonas punctata, Aeromonas sobria, and Shewanella putrefaciens. The highest percentage (88.4%) of strains was resistant to polymyxin B followed by 69% to lincomycin, 61.5% to benzilpenicillin, 57.7% to ampicillin, and 50% to carbenicillin. A low level of resistance (4%) was found to kanamycin (8%), to streptomycin (11.5%), to neomycin and tetracycline, and (15%) to erythromycin. No resistance was found to gentamycin, monomycin, and chloroamphenicol. The majority (80.7%) of strains was multidrug-resistant. Ninety-two percent of all strains carried plasmid DNA of various sizes.

  13. Polyphasic characterization of Aeromonas salmonicida isolates recovered from salmonid and non-salmonid fish

    USGS Publications Warehouse

    Diamanka, A.; Loch, T.P.; Cipriano, R.C.; Faisal, M.

    2013-01-01

    Michigan's fisheries rely primarily upon the hatchery propagation of salmonid fish for release in public waters. One limitation on the success of these efforts is the presence of bacterial pathogens, including Aeromonas salmonicida, the causative agent of furunculosis. This study was undertaken to determine the prevalence of A. salmonicida in Michigan fish, as well as to determine whether biochemical or gene sequence variability exists among Michigan isolates. A total of 2202 wild, feral and hatchery-propagated fish from Michigan were examined for the presence of A. salmonicida. The examined fish included Chinook salmon, Oncorhynchus tshawytscha (Walbaum), coho salmon, O. kisutcha (Walbaum), steelhead trout, O. mykiss (Walbaum), Atlantic salmon, Salmo salar L., brook trout, Salvelinus fontinalis (Mitchill), and yellow perch, Perca flavescens (Mitchill). Among these, 234 fish yielded a brown pigment-producing bacterium that was presumptively identified as A. salmonicida. Further phenotypic and phylogenetic analyses identified representative isolates as Aeromonas salmonicida subsp. salmonicida and revealed some genetic and biochemical variability. Logistic regression analyses showed that infection prevalence varied according to fish species/strain, year and gender, whereby Chinook salmon and females had the highest infection prevalence. Moreover, this pathogen was found in six fish species from eight sites, demonstrating its widespread nature within Michigan.

  14. Bioremediation and Detoxification of Synthetic Wastewater Containing Triarylmethane Dyes by Aeromonas hydrophila Isolated from Industrial Effluent

    PubMed Central

    Ogugbue, Chimezie Jason; Sawidis, Thomas

    2011-01-01

    Economical and bio-friendly approaches are needed to remediate dye-contaminated wastewater from various industries. In this study, a novel bacterial strain capable of decolorizing triarylmethane dyes was isolated from a textile wastewater treatment plant in Greece. The bacterial isolate was identified as Aeromonas hydrophila and was shown to decolorize three triarylmethane dyes tested within 24 h with color removal in the range of 72% to 96%. Decolorization efficiency of the bacterium was a function of operational parameters (aeration, dye concentration, temperature, and pH) and the optimal operational conditions obtained for decolorization of the dyes were: pH 7-8, 35°C and culture agitation. Effective color removal within 24 h was obtained at a maximum dye concentration of 50 mg/L. Dye decolorization was monitored using a scanning UV/visible spectrophotometer which indicated that decolorization was due to the degradation of dyes into non-colored intermediates. Phytotoxicity studies carried out using Triticum aestivum, Hordeum vulgare, and Lens esculenta revealed the triarylmethane dyes exerted toxic effects on plant growth parameters monitored. However, significant reduction in toxicity was obtained with the decolorized dye metabolites thus, indicating the detoxification of the dyes following degradation by Aeromonas hydrophila. PMID:21808740

  15. Molecular characterization of tetracycline- and quinolone-resistant Aeromonas salmonicida isolated in Korea

    PubMed Central

    Kim, Ji Hyung; Hwang, Sun Young; Son, Jee Soo; Han, Jee Eun; Jun, Jin Woo; Shin, Sang Phil; Choresca, Casiano; Choi, Yun Jaie; Park, Yong Ho

    2011-01-01

    The antibiotic resistance of 16 Aeromonas (A.) salmonicida strains isolated from diseased fish and environmental samples in Korea from 2006 to 2009 were investigated in this study. Tetracycline or quinolone resistance was observed in eight and 16 of the isolates, respectively, based on the measured minimal inhibitory concentrations. Among the tetracycline-resistant strains, seven of the isolates harbored tetA gene and one isolate harbored tetE gene. Additionally, quinolone-resistance determining regions (QRDRs) consisting of the gyrA and parC genes were amplified and sequenced. Among the quinolone-resistant A. salmonicida strains, 15 harbored point mutations in the gyrA codon 83 which were responsible for the corresponding amino acid substitutions of Ser83→Arg83 or Ser83→Asn83. We detected no point mutations in other QRDRs, such as gyrA codons 87 and 92, and parC codons 80 and 84. Genetic similarity was assessed via pulsed-field gel electrophoresis, and the results indicated high clonality among the Korean antibiotic-resistant strains of A. salmonicida. PMID:21368562

  16. The Main Aeromonas Pathogenic Factors

    PubMed Central

    Tomás, J. M.

    2012-01-01

    The members of the Aeromonas genus are ubiquitous, water-borne bacteria. They have been isolated from marine waters, rivers, lakes, swamps, sediments, chlorine water, water distribution systems, drinking water and residual waters; different types of food, such as meat, fish, seafood, vegetables, and processed foods. Aeromonas strains are predominantly pathogenic to poikilothermic animals, and the mesophilic strains are emerging as important pathogens in humans, causing a variety of extraintestinal and systemic infections as well as gastrointestinal infections. The most commonly described disease caused by Aeromonas is the gastroenteritis; however, no adequate animal model is available to reproduce this illness caused by Aeromonas. The main pathogenic factors associated with Aeromonas are: surface polysaccharides (capsule, lipopolysaccharide, and glucan), S-layers, iron-binding systems, exotoxins and extracellular enzymes, secretion systems, fimbriae and other nonfilamentous adhesins, motility and flagella. PMID:23724321

  17. Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract.

    PubMed

    Hayes, Samuel L; Lye, Dennis J; McKinstry, Craig A; Vesper, Stephen J

    2010-01-01

    Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus. Microarray profiling of murine small intestinal extracts, 24 h after oral infection with an A. caviae strain, provides evidence of a Th1 type immune response. A large number of gamma-interferon (gamma-IFN) induced genes are up-regulated as well as several tumor necrosis factor-alpha (TNF-alpha) transcripts. Aeromonas caviae has always been considered an opportunistic pathogen because it lacks obvious virulence factors. This current effort suggests that an A. caviae strain can colonize the murine intestinal tract and cause what has been described by others as a dysregulatory cytokine response. This response could explain why a number of diarrheal waterborne disease cases have been attributed to A. caviae even though it lacks obvious enteropathogenic properties.

  18. Pathogenicity of Aeromonas hydrophila isolated from the Malaysian Sea against coral (Turbinaria sp.) and sea bass (Lates calcarifer).

    PubMed

    Hamid, Rahimi; Ahmad, Asmat; Usup, Gires

    2016-09-01

    A study was carried out to determine the pathogenicity (hemolytic activity) on corals (Turbinaria sp.) and sea bass (Lates calcarifer) of Aeromonas hydrophila from water, sediment, and coral. Samples were collected from coastal water and coral reef areas. One hundred and sixty-two isolates were successfully isolated. Out of 162, 95 were from seawater, 49 from sediment, and 18 from coral. Sixteen isolates were picked and identified. Isolates were identified using a conventional biochemical test, the API 20NE kit, and 16S rRNA nucleotide sequences. Hemolytic activity was determined. Out of 16 isolates, 14 isolates were β-hemolytic and two isolates were non-hemolytic. Corals infected with A. hydrophila suffered bleaching. Similar effect was observed for both hemolytic and non-hemolytic isolates. Intramuscular injection of A. hydrophila into sea bass resulted in muscular bleeding and death. Higher infection rates were obtained from hemolytic compared to non-hemolytic strains of A. hydrophila isolates. PMID:27221587

  19. Isolation and characterization of Aeromonas schubertii from diseased snakehead, Channa maculata (Lacepède).

    PubMed

    Chen, Y F; Liang, R S; Zhuo, X L; Wu, X T; Zou, J X

    2012-06-01

    Pure bacterial cultures were isolated from diseased snakeheads, Channa maculata (Lacepède), suffering high mortality in a farm in Zhongshan, southern China. Three isolates, namely ZS20100725, ZS20100725-1 and ZS20100725-2, were identified as Aeromonas schubertii. All the isolates showed high 16S rRNA sequence similarities with A. schubertii. The isolates exhibited strong virulence to snakeheads in experimental challenges with LD(50) ranging between 1.4 × 10(4) and 6.4 × 10(6) CFU g(-1). Two of the isolates were positive for haemolysin, elastase, lipase and lecithinase by phenotypic determination, which was further confirmed by PCR amplification of the haemolysin and elastase genes. In sterile liquid medium, the best growth conditions of strain ZS20100725 were 30 °C, pH 7 and 0.5% salinity (w/v). Antibiotic susceptibility tests showed that strain ZS20100725 was susceptible to cefoxitin, cefoperazone and chloramphenicol. Furthermore, histopathology of diseased snakeheads infected with A. schubertii showed necrosis and congestion in liver, kidney and spleen and also damage to the cardiac muscle, intestine and gills.

  20. Isolation and Seroprevalence of Aeromonas spp. Among Common Food Animals Slaughtered in Nagpur, Central India.

    PubMed

    Gowda, Tanuja K G M; Reddy, Vishwanatha R A P; Devleesschauwer, Brecht; Zade, Nandkishor N; Chaudhari, Sandeep P; Khan, Waqar A; Shinde, Shilpa V; Patil, Archana R

    2015-07-01

    Aeromonads are ubiquitous foodborne pathogens with a global distribution. Animal-origin foods and contaminated animals are the main sources of Aeromonas infection to humans. So far little is known about the occurrence of Aeromonas spp. in food-producing animals in India. The present study was conducted to determine the prevalence and seroprevalence of Aeromonas species from 50 each of meat, blood, and sera samples collected from cattle, buffaloes, goats, and pigs slaughtered in and around Nagpur, Central India. Alkaline peptone water and ampicillin dextrin agar were used to isolate Aeromonas spp. An indirect enzyme-linked immunosorbent assay (ELISA) was standardized by use of whole-cell antigen (WC) and outer membrane protein (OMP) of Aeromonas hydrophila (MTCC 646). Aeromonads were isolated from 44 (22%) of the meat samples, and 1 (0.5%) from the blood samples. Seroprevalence by indirect ELISA-based WC antigen was estimated as 68% in cattle, 44% in buffaloes, 60% in goats, and 30% in pigs. OMP-based ELISA yielded a seroprevalence of 56%, 48%, 52%, and 22% in cattle, buffaloes, goats, and pigs, respectively. The results revealed that OMP-based ELISA and WC-based ELISA were in agreement with one another. Isolation along with high seropositivity demonstrates the presence of foodborne Aeromonas spp. in the Nagpur city of Central India.

  1. Complete Genome Sequence of the Type Strain of Aeromonas schubertii, ATCC 43700

    PubMed Central

    Liu, Lihui; Zhang, Defeng; Fu, Xiaozhe; Shi, Cunbin; Lin, Qiang

    2016-01-01

    We sequenced the complete genome of the type strain of Aeromonas schubertii, ATCC 43700. The full genome sequence of A. schubertii ATCC 43700 is 4,356,858 bp, which encodes 3,842 proteins and contains 110 predicted RNA genes. PMID:26893413

  2. Antibiotic Susceptibility Profile of Aeromonas Species Isolated from Wastewater Treatment Plant

    PubMed Central

    Igbinosa, Isoken H.; Okoh, Anthony I.

    2012-01-01

    This study assessed the prevalence of antibiotic-resistant Aeromonas species isolated from Alice and Fort Beaufort wastewater treatment plant in the Eastern Cape Province of South Africa. Antibiotic susceptibility was determined using the disc diffusion method, and polymerase chain reaction (PCR) assay was employed for the detection of antibiotics resistance genes. Variable susceptibilities were observed against ciprofloxacin, chloramphenicol, nalidixic acid, gentamicin, minocycline, among others. Aeromonas isolates from both locations were 100% resistant to penicillin, oxacillin, ampicillin, and vancomycin. Higher phenotypic resistance was observed in isolates from Fort Beaufort compared to isolates from Alice. Class A pse1 β-lactamase was detected in 20.8% of the isolates with a lower detection rate of 8.3% for blaTEM gene. Class 1 integron was present in 20.8% of Aeromonas isolates while class 2 integron and TetC gene were not detected in any isolate. The antibiotic resistance phenotypes observed in the isolates and the presence of β-lactamases genes detected in some isolates are of clinical and public health concern as this has consequences for antimicrobial chemotherapy of infections associated with Aeromonas species. This study further supports wastewater as potential reservoirs of antibiotic resistance determinants in the environment. PMID:22927788

  3. Molecular characterization of Aeromonas species isolated from farmed eels (Anguilla japonica).

    PubMed

    Yi, Seung-Won; You, Myung-Jo; Cho, Ho-Seong; Lee, Chang-Seop; Kwon, Joong-Ki; Shin, Gee-Wook

    2013-05-31

    Seventy Aeromonas strains were identified by phylogenetic analysis using housekeeping genes (gyrB and rpoD) in order to investigate etiological agents for aeromoniasis in farmed eels (Anguilla japonica). The phylogenetic analysis showed that Aeromonas aquariorum (n=22, 31.4%) was the predominant species among the investigated eel strains, followed by Aeromonas caviae (n=16, 22.9%), A. veronii (n=13, 18.6%), A. hydrophila (n=12, 17.1%), A. jandaei (n=4, 5.7%), A. media (n=2, 2.9%), and A. trota (n=1, 1.4%). The potential virulence of the present strains was estimated by performing PCR assays using the following seven virulence genes: cytotoxic enterotoxin (act), two cytotonic enterotoxins (alt and ast), glycerophospholipid:cholesterol acyltransferase (gcaT), DNase (exu), lipase (lip), and flagellin (fla). The detection rates of act, alt, ast, gcaT, exu, lip, and fla among all 70 strains were 91.4%, 55.7%, 27.1%, 97.1%, 95.7%, 100%, and 98.6%, respectively. In genotyping of enterotoxin genes, act(+)/alt(+)/ast(+), act(+)/alt(+)/ast(-), and act(+)/alt(-)/ast(-) genotypes were prevalent in A. hydrophila (8/12 strains), A. aquariorum (13/22 strains), and A. caviae (14/16 strains), respectively, suggesting a high heterogeneity among Aeromonas species. In this study, A. aquariorum, which has been an unrecorded species in Korea, can be an etiological agent for aeromoniasis of eel.

  4. Detection and Whole-Genome Sequencing of Carbapenemase-Producing Aeromonas hydrophila Isolates from Routine Perirectal Surveillance Culture

    PubMed Central

    Hughes, Heather Y.; Lau, Anna F.; Dekker, John P.; Michelin, Angela V.; Youn, Jung-Ho; Henderson, David K.; Frank, Karen M.; Segre, Julia A.

    2016-01-01

    Perirectal surveillance cultures and a stool culture grew Aeromonas species from three patients over a 6-week period and were without epidemiological links. Detection of the blaKPC-2 gene in one isolate prompted inclusion of non-Enterobacteriaceae in our surveillance culture workup. Whole-genome sequencing confirmed that the isolates were unrelated and provided data for Aeromonas reference genomes. PMID:26888898

  5. Molecular characterization of Aeromonas spp. and Vibrio cholerae O1 isolated during a diarrhea outbreak.

    PubMed

    Mendes-Marques, Carina Lucena; Nascimento, Larissa Mélo do; Theophilo, Grace Nazareth Diogo; Hofer, Ernesto; Melo Neto, Osvaldo Pompílio de; Leal, Nilma Cintra

    2012-12-01

    This work aimed to assess pathogenic potential and clonal relatedness of Aeromonas sp. and Vibrio cholerae isolates recovered during a diarrhea outbreak in Brazil. Clinical and environmental isolates were investigated for the presence of known pathogenic genes and clonal relatedness was assessed by intergenic spacer region (ISR) 16S-23S amplification. Four Aeromonas genes (lip, exu, gcat, flaA/B) were found at high overall frequency in both clinical and environmental isolates although the lip gene was specifically absent from selected species. A fifth gene, aerA, was rarely found in A. caviae, the most abundant species. The ISR profile revealed high heterogeneity among the Aeromonas isolates and no correlation with species identification. In contrast, in all the V. cholerae isolates the four genes investigated (ctxA, tcpA, zot and ace) were amplified and revealed homogeneous ISR and RAPD profiles. Although Aeromonas isolates were the major enteric pathogen recovered, their ISR profiles are not compatible with a unique cause for the diarrhea events, while the clonal relationship clearly implicates V. cholerae in those cases from which it was isolated. These results reinforce the need for a better definition of the role of aeromonads in diarrhea and whether they benefit from co-infection with V. cholerae.

  6. Molecular characterization of Shewanella and Aeromonas isolates associated with spoilage of Common carp (Cyprinus carpio).

    PubMed

    Beaz-Hidalgo, Roxana; Agüeria, Daniela; Latif-Eugenín, Fadua; Yeannes, Maria I; Figueras, Maria J

    2015-01-01

    Storage in ice is a common way of preserving commercial fish species but some microorganisms can still contaminate and participate in the spoilage of the product; therefore, identification of potential harmful microbes is important. Thirteen colonies were isolated from common carp (Cyprinus carpio) that had been stored in ice, whose phenotypic identification revealed that they belonged to the genera Aeromonas (n = 5) and Shewanella (n = 8). Molecular genotyping with ERIC-PCR showed clonality only among two of the five Aeromonas isolates and for two groups (n = 3; n = 2) of the eight Shewanella isolates. Sequencing the rpoD gene showed that four Aeromonas isolates belonged to the species Aeromonas salmonicida and one to A. sobria. Of the eight Shewanella, seven isolates cluster with Shewanella putrefaciens and one with Shewanella profunda in the 16S rRNA phylogenetic tree. However, analysis of the gyrB gene showed that these eight isolates could constitute a new species closely related to S. baltica. The Shewanella and A. salmonicida isolates produce off-odours and reduce trimethylamine oxide, indicating that they might contribute to the spoilage of the fish. PMID:25790506

  7. Molecular characterization of Shewanella and Aeromonas isolates associated with spoilage of Common carp (Cyprinus carpio).

    PubMed

    Beaz-Hidalgo, Roxana; Agüeria, Daniela; Latif-Eugenín, Fadua; Yeannes, Maria I; Figueras, Maria J

    2015-01-01

    Storage in ice is a common way of preserving commercial fish species but some microorganisms can still contaminate and participate in the spoilage of the product; therefore, identification of potential harmful microbes is important. Thirteen colonies were isolated from common carp (Cyprinus carpio) that had been stored in ice, whose phenotypic identification revealed that they belonged to the genera Aeromonas (n = 5) and Shewanella (n = 8). Molecular genotyping with ERIC-PCR showed clonality only among two of the five Aeromonas isolates and for two groups (n = 3; n = 2) of the eight Shewanella isolates. Sequencing the rpoD gene showed that four Aeromonas isolates belonged to the species Aeromonas salmonicida and one to A. sobria. Of the eight Shewanella, seven isolates cluster with Shewanella putrefaciens and one with Shewanella profunda in the 16S rRNA phylogenetic tree. However, analysis of the gyrB gene showed that these eight isolates could constitute a new species closely related to S. baltica. The Shewanella and A. salmonicida isolates produce off-odours and reduce trimethylamine oxide, indicating that they might contribute to the spoilage of the fish.

  8. Exposure to pairs of Aeromonas strains enhances virulence in the Caenorhabditis elegans infection model.

    PubMed

    Mosser, Thomas; Talagrand-Reboul, Emilie; Colston, Sophie M; Graf, Joerg; Figueras, Maria J; Jumas-Bilak, Estelle; Lamy, Brigitte

    2015-01-01

    Aeromonad virulence remains poorly understood, and is difficult to predict from strain characteristics. In addition, infections are often polymicrobial (i.e., are mixed infections), and 5-10% of such infections include two distinct aeromonads, which has an unknown impact on virulence. In this work, we studied the virulence of aeromonads recovered from human mixed infections. We tested them individually and in association with other strains with the aim of improving our understanding of aeromonosis. Twelve strains that were recovered in pairs from six mixed infections were tested in a virulence model of the worm Caenorhabditis elegans. Nine isolates were weak worm killers (median time to death, TD50, ≥7 days) when administered alone. Two pairs showed enhanced virulence, as indicated by a significantly shortened TD50 after co-infection vs. infection with a single strain. Enhanced virulence was also observed for five of the 14 additional experimental pairs, and each of these pairs included one strain from a natural synergistic pair. These experiments indicated that synergistic effects were frequent and were limited to pairs that were composed of strains belonging to different species. The genome content of virulence-associated genes failed to explain virulence synergy, although some virulence-associated genes that were present in some strains were absent from their companion strain (e.g., T3SS). The synergy observed in virulence when two Aeromonas isolates were co-infected stresses the idea that consideration should be given to the fact that infection does not depend only on single strain virulence but is instead the result of a more complex interaction between the microbes involved, the host and the environment. These results are of interest for other diseases in which mixed infections are likely and in particular for water-borne diseases (e.g., legionellosis, vibriosis), in which pathogens may display enhanced virulence in the presence of the right partner. This

  9. Exposure to pairs of Aeromonas strains enhances virulence in the Caenorhabditis elegans infection model

    PubMed Central

    Mosser, Thomas; Talagrand-Reboul, Emilie; Colston, Sophie M.; Graf, Joerg; Figueras, Maria J.; Jumas-Bilak, Estelle; Lamy, Brigitte

    2015-01-01

    Aeromonad virulence remains poorly understood, and is difficult to predict from strain characteristics. In addition, infections are often polymicrobial (i.e., are mixed infections), and 5–10% of such infections include two distinct aeromonads, which has an unknown impact on virulence. In this work, we studied the virulence of aeromonads recovered from human mixed infections. We tested them individually and in association with other strains with the aim of improving our understanding of aeromonosis. Twelve strains that were recovered in pairs from six mixed infections were tested in a virulence model of the worm Caenorhabditis elegans. Nine isolates were weak worm killers (median time to death, TD50, ≥7 days) when administered alone. Two pairs showed enhanced virulence, as indicated by a significantly shortened TD50 after co-infection vs. infection with a single strain. Enhanced virulence was also observed for five of the 14 additional experimental pairs, and each of these pairs included one strain from a natural synergistic pair. These experiments indicated that synergistic effects were frequent and were limited to pairs that were composed of strains belonging to different species. The genome content of virulence-associated genes failed to explain virulence synergy, although some virulence-associated genes that were present in some strains were absent from their companion strain (e.g., T3SS). The synergy observed in virulence when two Aeromonas isolates were co-infected stresses the idea that consideration should be given to the fact that infection does not depend only on single strain virulence but is instead the result of a more complex interaction between the microbes involved, the host and the environment. These results are of interest for other diseases in which mixed infections are likely and in particular for water-borne diseases (e.g., legionellosis, vibriosis), in which pathogens may display enhanced virulence in the presence of the right partner. This

  10. Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract

    SciTech Connect

    Hayes, S L; Lye, D J; McKinstry, Craig A.; Vesper, Sephen J.

    2010-01-01

    Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus. Microarray profiling of murine small intestinal extracts, 24 hours after oral infection with an A. caviae strain, provides evidence of a Th1 type immune response. A large number of gamma-interferon (γ-IFN) induced genes are up-regulated as well as several tumor necrosis factor-alpha (TNF-α) transcripts. A. caviae has always been considered as opportunistic pathogen because it lacks obvious virulence factors. This current effort suggests that an A. caviae strain can colonize the murine intestinal tract and cause what has been described by others as a dysregulatory cytokine response. This response could explain why a number of diarrheal waterborne disease cases have been attributed to A. caviae even though it lacks obvious enteropathogenic properties.

  11. Draft Genome Sequence of Aeromonas caviae 8LM, Isolated from Stool Culture of a Child with Diarrhea.

    PubMed

    Moriel, Bárbara; Cruz, Leonardo M; Dallagassa, Cibelle B; Faoro, Helisson; de Souza, Emanuel M; Pedrosa, Fábio O; Rego, Fabiane G M; Picheth, Geraldo; Fadel-Picheth, Cyntia M T

    2015-05-21

    Aeromonas spp. are Gram-negative rods ubiquitous in aquatic environments; however, some species are able to cause a variety of infections in humans. Here, we report the draft genome sequence of Aeromonas caviae 8LM isolated from stool culture from a child with diarrhea in southern Brazil.

  12. Draft Genome Sequence of Aeromonas caviae 8LM, Isolated from Stool Culture of a Child with Diarrhea

    PubMed Central

    Moriel, Bárbara; Dallagassa, Cibelle B.; Faoro, Helisson; de Souza, Emanuel M.; Pedrosa, Fábio O.; Rego, Fabiane G. M.; Picheth, Geraldo

    2015-01-01

    Aeromonas spp. are Gram-negative rods ubiquitous in aquatic environments; however, some species are able to cause a variety of infections in humans. Here, we report the draft genome sequence of Aeromonas caviae 8LM isolated from stool culture from a child with diarrhea in southern Brazil. PMID:25999559

  13. VIRULENCE FACTORS OF AEROMONAS: A GENETIC CHARACTERIZATION OF DRINKING WATER ISOLATES

    EPA Science Inventory

    A survey of finished drinking water conducted by the US EPA during 2000-2001, revealed that 8 out of 18 water utilities encompassing several states (NY, KY, IA, OH) were contaminated with aeromonas species. Altogether 205 organisms were isolated by EPA method 1601. All of the ...

  14. Molecular Characterization of a Functional Type VI Secretion System from a Clinical Isolate of Aeromonas hydrophilia

    EPA Science Inventory

    Our laboratory recently molecularly characterized the type II secretion system (T2SS)-associated cytotoxic enterotoxin (Act) and the T3SS-secreted AexU effector from a diarrheal isolate SSU of Aeromonas hydrophila. The role of these toxin proteins in the pathogenesis of A. hydrop...

  15. Molecular characterization of a functional type VI secretion system from a clinical isolate of Aeromonas hydrophila

    EPA Science Inventory

    Our laboratory recently molecularly characterized the type II secretion system (T2SS)-associated cytotoxic enterotoxin (Act) and the T3SS-secreted AexU effector from a diarrheal isolate SSU of Aeromonas hydrophila. The role of these toxin proteins in the pathogenesis of A. hydrop...

  16. A Mouse Model for Characterization of Gastrointestinal Colonization Rates Among Environmental Aeromonas Isolates

    EPA Science Inventory

    The colonization rates of ten different environmental isolates of Aeromonas were determined using a novel mouse-streptomycin pre-treatment method. A novel streptomycin pre-treatment prepared animals with a transient alteration in colon flora that allowed colonization by Aeromon...

  17. The involvement of tetA and tetE tetracycline resistance genes in plasmid and chromosomal resistance of Aeromonas in Brazilian strains.

    PubMed

    Balassiano, Ilana Teruszkin; Bastos, Maria do Carmo de Freire; Madureira, Danielle Jannuzzi; Silva, Iris Gripp da; Freitas-Almeida, Angela Corrêa de; Oliveira, Selma Soares de

    2007-11-01

    This study analyzed the involvement of tetA and tetE genes in the tetracycline resistance of 16 strains of genus Aeromonas, isolated from clinical and food sources. Polymerase chain reactions revealed that 37.5% of the samples were positive for tetA, and also 37.5% were tetE positive. One isolate was positive for both genes. Only the isolate A. caviae 5.2 had its resistance associated to the presence of a plasmid, pSS2. The molecular characterization of pSS2 involved the construction of its restriction map and the determination of its size. The digestion of pSS2 with HindIII originated two fragments (A and B) that were cloned separately into the pUC18 vector. The tetA gene was shown to be located on the HindIII-A fragment by PCR. After transforming a tetracycline-sensitive strain with pSS2, the transformants expressed the resistance phenotype and harbored a plasmid whose size was identical to that of pSS2. The results confirmed the association between pSS2 and the tetracycline resistance phenotype, and suggest a feasible dissemination of tetA and tetE among strains of Aeromonas. This study suggests the spreading tetA and tetE genes in Aeromonas in Brazil and describes a resistance plasmid that probably contributes to the dissemination of the resistance.

  18. A comparative study of clinical Aeromonas dhakensis and Aeromonas hydrophila isolates in southern Taiwan: A. dhakensis is more predominant and virulent.

    PubMed

    Chen, P-L; Wu, C-J; Chen, C-S; Tsai, P-J; Tang, H-J; Ko, W-C

    2014-07-01

    Aeromonas dhakensis, often phenotypically identified as Aeromonas hydrophila, is an important human pathogen. The present study aimed to compare the clinical and biological features of A. dhakensis and A. hydrophila isolates from human wounds. A total of 80 Aeromonas wound isolates collected between January 2004 and April 2011 were analysed. The species was identified by the DNA sequence matching of rpoD and gyrB (or rpoB if necessary). Most of the Aeromonas isolates were identified as A. dhakensis (37, 46.3%), and 13 (16.3%) as A. hydrophila. Both species alone can cause severe skin and soft-tissue infections. More A. dhakensis isolates were found in wounds exposed to environmental water (32.4% vs 0%, p 0.042). More biofilm formation was noted among A. dhakensis isolates (mean optical density at 570 nm, 1.23 ± 0.09 vs 0.78 ± 0.21, p 0.03). The MICs of ceftriaxone, imipenem and gentamicin for A. dhakensis isolates were higher (p <0.0001, <0.04, and <0.01, respectively). The survival rates of Caenorhabditis elegans co-incubated with A. dhakensis from day 1 to day 3 were lower than those of worms infected with A. hydrophila in liquid toxicity assays (all p values <0.01). Isolates of A. dhakensis exhibited more cytotoxicity, as measured by the released leucocyte lactate dehydrogenase levels in human normal skin fibroblast cell lines (29.6 ± 1.2% vs 20.6 ± 0.6%, p <0.0001). The cytotoxin gene ast was primarily present in A. hydrophila isolates (100% vs 2.7%, p <0.0001). In summary, A. dhakensis is the predominant species among Aeromonas wound isolates, and more virulent than A. hydrophila.

  19. Virulence Diversity among Bacteremic Aeromonas Isolates: Ex Vivo, Animal, and Clinical Evidences

    PubMed Central

    Chen, Po-Lin; Wu, Chi-Jung; Tsai, Pei-Jane; Tang, Hung-Jen; Chuang, Yin-Ching; Lee, Nan-Yao; Lee, Ching-Chi; Li, Chia-Wen; Li, Ming-Chi; Chen, Chi-Chung; Tsai, Hung-Wen; Ou, Chun-Chun; Chen, Chang-Shi; Ko, Wen-Chien

    2014-01-01

    Background The objective of this study was to compare virulence among different Aeromonas species causing bloodstream infections. Methodology/Principal Findings Nine of four species of Aeromonas blood isolates, including A. dhakensis, A. hydrophila, A. veronii and A. caviae were randomly selected for analysis. The species was identified by the DNA sequence matching of rpoD. Clinically, the patients with A. dhakensis bacteremia had a higher sepsis-related mortality rate than those with other species (37.5% vs. 0%, P = 0.028). Virulence of different Aeromonas species were tested in C. elegans, mouse fibroblast C2C12 cell line and BALB/c mice models. C. elegans fed with A. dhakensis and A. caviae had the lowest and highest survival rates compared with other species, respectively (all P values <0.0001). A. dhakensis isolates also exhibited more cytotoxicity in C2C12 cell line (all P values <0.0001). Fourteen-day survival rate of mice intramuscularly inoculated with A. dhakensis was lower than that of other species (all P values <0.0001). Hemolytic activity and several virulence factor genes were rarely detected in the A. caviae isolates. Conclusions/Significance Clinical data, ex vivo experiments, and animal studies suggest there is virulence variation among clinically important Aeromonas species. PMID:25375798

  20. Phenotypical characteristics, genetic identification, and antimicrobial sensitivity of Aeromonas species isolated from farmed rainbow trout (Onchorynchus mykiss) in Mexico.

    PubMed

    Vega-Sánchez, Vicente; Acosta-Dibarrat, Jorge; Vega-Castillo, Fernando; Castro-Escarpulli, Graciela; Aguilera-Arreola, Ma Guadalupe; Soriano-Vargas, Edgardo

    2014-02-01

    In the present study, Aeromonas isolates from diseased and healthy farmed rainbow trout (Oncorhynchus mykiss) in Mexico, were characterized phenotypically and identified to species level by using 16S rDNA RFLP-PCR. A total of 50 isolates were included in the study and 10 Aeromonas species identified. The species A. veronii biovar sobria (22%), A. hydrophila (20%) and A. bestiarum (20%) were the most predominant. All isolates (100%) were resistant to cephalothin.

  1. Isolation of Aeromonas salmonicida from Human Blood Sample: A Case Report.

    PubMed

    Tewari, Rachna; Dudeja, Mridu; Nandy, Shyamasree; Das, Ayan Kumar

    2014-02-01

    Aeromonas salmonicida belonging to the genus Aeromonas, is a common pathogen that causes furunculosis and septicaemia in variety of fishes. It infects cold blooded vertebrates living at low temperatures mainly salmonid fish hence named salmonicida. Untill recently Aeromanas salmonicida is considered to be a fish pathogen. A. salmonicida is considered to be non-pathogenic for humans as it cannot grow at 37ºC. "However, In our laboratory culture plates and broths were incubated twice at 37ºC and each time same type of colonies were isolated which were identified as A. samonicida by Vitek 2 compact system bioMerieux, Inc. (Durham, N.C.)". By far no report has been received regarding its isolation from humans biological sample. Here we present the first report of A. salmonicida isolated from the human blood. PMID:24701507

  2. Complete genome sequence of Aeromonas hydrophila AL06-06

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila occurs in freshwater environments and infects fish and mammals. In this work, we report the complete genome sequence of Aeromonas hydrophila AL06-06, which was isolated from diseased goldfish and is being used for comparative genomic studies with A. hydrophila strains causing ba...

  3. CHARACTERIZATION OF AEROMONAS VIRULENCE USING AN IMMUNOCOMPROMISED MOUSE MODEL

    EPA Science Inventory

    An immunocompromised mouse model was used to characterize Aeromonas strains for their ability to cause opportunistic, extraintestinal infections. A total of 34 isolates of Aeromonas (A. hydrophila [n = 12]), A. veronii biotype sobria [n = 7], A. caviae [n = 4], A. enchelia [n = 4...

  4. Re-identification of Aeromonas isolates from rainbow trout and incidence of class 1 integron and β-lactamase genes.

    PubMed

    Vega-Sánchez, Vicente; Latif-Eugenín, Fadua; Soriano-Vargas, Edgardo; Beaz-Hidalgo, Roxana; Figueras, María José; Aguilera-Arreola, Ma Guadalupe; Castro-Escarpulli, Graciela

    2014-08-27

    Forty-eight Aeromonas isolates from rainbow trout previously identified by the 16S rDNA-RFLP technique were re-identified using 2 housekeeping genes (gyrB and rpoD). After sequencing the prevalences of the species were A. veronii (29.2%), A. bestiarum (20.8%), A. hydrophila (16.7%), A. sobria (10.4%), A. media (8.3%), A. popoffii (6.2%), A. allosaccharophila (2.1%), A. caviae (2.1%), A. salmonicida (2.1%) and one isolate (2.1%) belongs to a candidate new species "Aeromonas lusitana". Coincident identification results to the 16S rDNA-RFLP technique were only obtained for 68.8% of the isolates. PCR amplification of the enterobacterial repetitive intergenic consensus (ERIC-PCR) indicated that the 48 isolates belonged to 33 different ERIC genotypes. Several genotypes were isolated from different farms and organs in the same fish, indicating a systemic dissemination of the bacteria. The presence of genes (blaIMP, blaCphA/IMIS, blaTEM, blaSHV and intI1) that encode extended-spectrum beta-lactamases (ESBLs), metallo-beta-lactamases (MBLs) and class 1 integrons were studied by PCR. Only 39.6% (19/48) of the strains showed the presence of one or more resistance genes. The gene blaCphA/IMIS was detected in 29.2% of the isolates, followed by the intI1 (6.2%) and blaSHV (4.2%) genes. The variable region of class 1 integrons of the 3 positive isolates was sequenced revealing the presence of the gene cassette aadA1 (aminoglycoside transferase) that plays a role in streptomycin/spectinomycin resistance.

  5. Prevalence, virulence and antimicrobial resistance patterns of Aeromonas spp. isolated from children with diarrhea

    PubMed Central

    Soltan Dallal, Mohammad Mehdi; Mazaheri Nezhad Fard, Ramin; Kavan Talkhabi, Morteza; Aghaiyan, Leyla; Salehipour, Zohre

    2016-01-01

    Background Aeromonas spp. cause various intestinal and extraintestinal diseases. These bacteria are usually isolated from fecal samples, especially in children under five years old. The aim of this study was to assess the prevalence of Aeromonas spp. and their antimicrobial resistance profile in children with diarrhea referred to the Children Medical Center in Tehran, between 2013 and 2014. Methods A total number of 391 stool samples were collected from children with ages between 1 day and 14 years old, with diarrhea (acute or chronic), referred to the Children Hospital, Tehran, Iran, between 2013 and 2014. Samples were enriched in alkaline peptone water broth for 24 hours at 37 °C and then cultured. Suspicious colonies were analyzed through biochemical tests. Furthermore, antimicrobial susceptibility tests were carried out for the isolates. Isolates were further studied for act, ast, alt, aerA and hlyA virulence genes using polymerase chain reaction. Results In total, 12 isolates (3.1%) were identified as Aeromonas spp.; all were confirmed using the API-20E test. Of these isolates, five A. caviae (42%), four A. veronii (33%) and three A. hydrophila (25%) were identified in cases with gastroenteritis. Second to ampicillin (which was included in the growth medium used), the highest rate of antimicrobial resistance was seen against nalidixic acid and trimethoprim-sulfamethoxazole (5 isolates each, 41.6%) and the lowest rate of antimicrobial resistance was seen against gentamicin, amikacin and cefepime (none of the isolates). Results included 76.4% act, 64.7% ast, 71.5% alt, 83.3% aerA and 11.7% hlyA genes. Conclusion Aeromonas spp. are important due to their role in diarrhea in children; therefore, isolation and identification of these fecal pathogens should seriously be considered in medical laboratories. Since virulence genes play a significant role in gastroenteritis symptoms caused by these bacteria, Aeromonas species that include virulence genes are potentially

  6. Prevalence, virulence and antimicrobial resistance patterns of Aeromonas spp. isolated from children with diarrhea

    PubMed Central

    Soltan Dallal, Mohammad Mehdi; Mazaheri Nezhad Fard, Ramin; Kavan Talkhabi, Morteza; Aghaiyan, Leyla; Salehipour, Zohre

    2016-01-01

    Background Aeromonas spp. cause various intestinal and extraintestinal diseases. These bacteria are usually isolated from fecal samples, especially in children under five years old. The aim of this study was to assess the prevalence of Aeromonas spp. and their antimicrobial resistance profile in children with diarrhea referred to the Children Medical Center in Tehran, between 2013 and 2014. Methods A total number of 391 stool samples were collected from children with ages between 1 day and 14 years old, with diarrhea (acute or chronic), referred to the Children Hospital, Tehran, Iran, between 2013 and 2014. Samples were enriched in alkaline peptone water broth for 24 hours at 37 °C and then cultured. Suspicious colonies were analyzed through biochemical tests. Furthermore, antimicrobial susceptibility tests were carried out for the isolates. Isolates were further studied for act, ast, alt, aerA and hlyA virulence genes using polymerase chain reaction. Results In total, 12 isolates (3.1%) were identified as Aeromonas spp.; all were confirmed using the API-20E test. Of these isolates, five A. caviae (42%), four A. veronii (33%) and three A. hydrophila (25%) were identified in cases with gastroenteritis. Second to ampicillin (which was included in the growth medium used), the highest rate of antimicrobial resistance was seen against nalidixic acid and trimethoprim-sulfamethoxazole (5 isolates each, 41.6%) and the lowest rate of antimicrobial resistance was seen against gentamicin, amikacin and cefepime (none of the isolates). Results included 76.4% act, 64.7% ast, 71.5% alt, 83.3% aerA and 11.7% hlyA genes. Conclusion Aeromonas spp. are important due to their role in diarrhea in children; therefore, isolation and identification of these fecal pathogens should seriously be considered in medical laboratories. Since virulence genes play a significant role in gastroenteritis symptoms caused by these bacteria, Aeromonas species that include virulence genes are potentially

  7. Prevalence and antimicrobial susceptibilities of Vibrio, salmonella, and Aeromonas isolates from various uncooked seafoods in Thailand.

    PubMed

    Woodring, Joseph; Srijan, Apichai; Puripunyakom, Paksathorn; Oransathid, Wilawan; Wongstitwilairoong, Boonchai; Mason, Carl

    2012-01-01

    Uncooked seafood samples were collected from open markets and supermarkets in Bangkok, Thailand, and were examined for the presence of Vibrio, Salmonella, and Aeromonas species from January to February 2008. From 120 samples, 272 bacterial isolates were identified through biochemical testing. Of all sea bass, shrimp, oyster, and blood cockle samples (30 of each) that were processed for culture, 114 (95%) samples had at least one detectable isolate of Vibrio, Salmonella, or Aeromonas, leaving only 6 (5%) samples free of them. All oyster sample (100%) had at least one pathogen, followed by sea bass (97%), blood cockles (97%), and shrimp (90%). Overall, 111 (92%) of all samples had detectable Vibrio spp., 32 (27%) had detectable Aeromonas spp., and 25 (21%) had detectable Salmonella enterica. There was no overall difference between positive samples collected from fresh markets versus supermarkets (relative risk, 0.97; 95% CI, 0.89 to 1.05). Resistance to ampicillin among isolated pathogens was relatively high (56%), while resistance to 12 other antibiotics, including azithromycin, ciprofloxacin, and trimethoprim-sulfamethoxazole, was relatively low (0, 0, and 3%, respectively). Study results indicate that uncooked seafood in Bangkok, Thailand, commonly harbors enteric pathogens and that consumption of uncooked seafood should be avoided to reduce foodborne illnesses. PMID:22221354

  8. Persistence, transmission, and virulence characteristics of Aeromonas strains in a duckweed aquaculture-based hospital sewage water recycling plant in Bangladesh.

    PubMed

    Rahman, Mokhlasur; Huys, Geert; Rahman, Motiur; Albert, M John; Kühn, Inger; Möllby, Roland

    2007-03-01

    The persistence and transmission of Aeromonas in a duckweed aquaculture-based hospital sewage water treatment plant in Bangladesh was studied. A total of 670 samples from different sites of the hospital sewage water treatment plant, from feces of hospitalized children suffering from diarrhea, from environmental control ponds, and from feces of healthy humans were collected over a period of three years. In total, 1,315 presumptive Aeromonas isolates were biochemically typed by the PhenePlate rapid screening system (PhP-AE). A selection of 90 representative isolates was further analyzed with PhenePlate (PhP) extended typing (PhP-48), fatty acid methyl ester analysis, and amplified fragment length polymorphism (AFLP) fingerprinting. In addition, the prevalence of the putative virulence factors hemolysin and cytotoxin and the presence of the cytolytic enterotoxin gene (AHCYTOEN) were analyzed. Aeromonas was found at all sites of the treatment plant, in 40% of the samples from environmental control ponds, in 8.5% of the samples from hospitalized children suffering from diarrhea, and in 3.5% of samples from healthy humans. A significantly high number of Aeromonas bacteria was found in duckweed, which indicates that duckweed may serve as a reservoir for these bacteria. PhP-AE typing allowed identification of more than 192 distinct PhP types, of which 18 major PhP types (MTs) were found in multiple sites and during several occasions. AFLP fingerprinting revealed the prevalence of genotypically indistinguishable Aeromonas isolates among certain PhP MTs recovered from different sampling occasions and/or at multiple sites. Hemolytic and cytotoxic activities were observed in 43% of the tested strains, whereas 29% possessed the cytolytic enterotoxin gene AHCYTOEN. Collectively, two specific MTs associated with diarrhea were shown to exhibit high cytotoxicity. Furthermore, all tested isolates of these major types were positive for the cytolytic enterotoxin gene. In conclusion

  9. Isolation and Antimicrobial Testing of Aeromonas spp., Citrobacter spp., Cronobacter spp., Enterobacter spp., Escherichia spp., Klebsiella spp., and Trabulsiella spp. from the Gallbladder of Pigs.

    PubMed

    Evangelopoulou, Grammato; Filioussis, Georgios; Kritas, Spyridon; Kantere, Maria; Burriel, Angeliki R

    2015-01-01

    The presence of Gram-negative bacteria species, other than Salmonella spp., in the gallbladder of pigs was examined. Isolated Gram-negative bacteria were assigned to species using the Microgen™ GnA+B-ID Systems. Of the 64 isolated strains 43 were identified as Escherichia coli, seven as Enterobacter spp., three each as Klebsiella spp., Citrobacterfreundii, Aeromonas hydrophila and Cronobacter sakazakii and one each as Escherichiafergusonii and Trabulsiella guamensis. Their antibiograms showed very high resistance to ampicillin, amoxicillin, tetracycline, chloramphenicol and sulfamethoxazole/trimethoprim. It was concluded that the pigs' gallbladder is a reservoir of potentially pathogenic Gram-negative bacteria for pork consumers.

  10. Rapid quantitative detection of Aeromonas hydrophila strains associated with disease outbreaks in catfish aquaculture.

    PubMed

    Griffin, Matt J; Goodwin, Andrew E; Merry, Gwenn E; Liles, Mark R; Williams, Malachi A; Ware, Cynthia; Waldbieser, Geoffrey C

    2013-07-01

    A new strain of Aeromonas hydrophila has been implicated in significant losses in farm-raised catfish. Outbreaks attributable to this new strain began in Alabama in the summer of 2009 and have spread to Arkansas and Mississippi in subsequent years. These outbreaks mostly afflicted market-sized fish and resulted in considerable losses in short periods of time. The present research was designed to develop an expeditious diagnostic procedure to detect the new strains of A. hydrophila due to the rapid onset and biosecurity concerns associated with this new disease. A discriminatory quantitative polymerase chain reaction assay was developed using gene sequences unique to the virulent strains identified in a related comparative genomic study. Using this assay, suspect colonies on a culture plate can be positively identified as the new strain within 2 hr. The assay is repeatable and reproducible with a linear dynamic range covering 8 orders of magnitude and a sensitivity of approximately 7 copies of target DNA in a 15-µl reaction. In addition, the assay is able to detect and quantify the virulent strain from catfish tissues (0.025 g), pond water (40 ml), and sediments (0.25 g) with a sensitivity limit of approximately 100 bacteria in a sample. This assay provides rapid discrimination between the new virulent strain and more common A. hydrophila and is useful for epidemiological studies involving the detection and quantification of the virulent strain in environmental samples and fish tissues.

  11. Enumeration and confirmation of Aeromonas hydrophila, Aeromonas caviae, and Aeromonas sobria isolated from raw milk and other milk products in Northern Greece.

    PubMed

    Melas, D S; Papageorgiou, D K; Mantis, A I

    1999-05-01

    A total of 138 raw cow's and 57 raw ewe's milk samples; 80 pasteurized cow's milk samples; 39 Anthotyros cheese, 36 Manouri cheese, and 23 Feta cheese samples; and 15 rice pudding samples were examined for the presence and any countable population of Aeromonas species. Twenty-two (15.9%) of the 138 cow's milk samples analyzed were contaminated with A. hydrophila. In 13 of these samples, populations of 3.0x10(2) to 5.0x10(3) CFU/ml were counted in starch ampicillin agar (SAA). Eighteen cow's milk samples (13.0%) were contaminated with A. caviae, and in eight of these samples, populations of 2.0x10(2) to 3.0x10(3) CFU/ml were counted in SAA. Five cow's milk samples (3.6%) were contaminated with A. sobria, and in two of these samples, populations of 2.5x10(3) and 5.0x10(3) CFU/ml were counted in SAA. Eleven cow's milk samples (7.9%) were contaminated with other Aeromonas spp. not classified. Eight (14.0%) of the 57 ewe's milk samples analyzed were contaminated with A. hydrophila. In these samples, populations of 5.0x10(2) to 5.0x10(3) CFU/ml were counted in SAA. Six ewe's milk samples (10.5%) were contaminated with A. caviae, and populations of 1.5x10(2) to 1.0x10(3) CFU/ ml were counted in SAA. Two ewe's milk samples (3.5%) were contaminated with A. sobria, and populations counted in SAA were 5.0x10(2) and 1.0x10(3) CFU/ml. Four samples (7.0%) were contaminated with other Aeromonas spp. not classified. A. hydrophila was recovered in 4 (10.2%) and 3 (8.3%) of the Anthotyros and Manouri cheese samples analyzed, respectively, but no countable populations were noted in SAA. None of the pasteurized milk, Feta cheese, and rice pudding samples yielded Aeromonas spp. The results of this work indicate that motile Aeromonas are common in raw milk in Greece. Also, the presence of A. hydrophila in the whey cheeses Anthotyros and Manouri indicates that postprocessing contaminations of these products with motile Aeromonas may occur during production.

  12. Insights into the Quorum-Sensing Activity in Aeromonas hydrophila Strain M013 as Revealed by Whole-Genome Sequencing.

    PubMed

    Tan, Wen-Si; Yin, Wai-Fong; Chan, Kok-Gan

    2015-01-01

    Aeromonas hydrophila species can be found in warm climates and can survive in different environments. They possess the ability to communicate within their populations, which is known as quorum sensing. In this work, we present the draft genome sequence of A. hydrophila M013, a bacterium isolated from a Malaysian tropical rainforest waterfall. PMID:25555739

  13. Draft genome sequences of two Aeromonas salmonicida subsp. salmonicida isolates harboring plasmids conferring antibiotic resistance.

    PubMed

    Vincent, Antony T; Tanaka, Katherine H; Trudel, Melanie V; Frenette, Michel; Derome, Nicolas; Charette, Steve J

    2015-02-01

    The bacterium Aeromonas salmonicida is the etiological agent of furunculosis, a widespread fish disease causing important economic losses to the fish farming industry. Antibiotic treatments in fish farms may be challenging given the existence of multidrug-resistant isolates of this bacterium. Here, we report the draft genome sequences of the 2004-05MF26 and 2009-144K3 isolates, which harbor plasmids conferring antibiotic resistance. Both isolates also carry the large plasmid pAsa5, which is known to encode a type three secretion system (TTSS) and the pAsal1 plasmid which has the aopP gene producing a TTSS effector. These two isolates are good representatives of the plasmid diversity in A. salmonicida subsp. salmonicida. PMID:25724776

  14. Implication of lateral genetic transfer in the emergence of Aeromonas hydrophila isolates of epidemic outbreaks in channel catfish.

    PubMed

    Hossain, Mohammad J; Waldbieser, Geoffrey C; Sun, Dawei; Capps, Nancy K; Hemstreet, William B; Carlisle, Kristen; Griffin, Matt J; Khoo, Lester; Goodwin, Andrew E; Sonstegard, Tad S; Schroeder, Steven; Hayden, Karl; Newton, Joseph C; Terhune, Jeffery S; Liles, Mark R

    2013-01-01

    To investigate the molecular basis of the emergence of Aeromonas hydrophila responsible for an epidemic outbreak of motile aeromonad septicemia of catfish in the Southeastern United States, we sequenced 11 A. hydrophila isolates that includes five reference and six recent epidemic isolates. Comparative genomics revealed that recent epidemic A. hydrophila isolates are highly clonal, whereas reference isolates are greatly diverse. We identified 55 epidemic-associated genetic regions with 313 predicted genes that are present in epidemic isolates but absent from reference isolates and 35% of these regions are located within genomic islands, suggesting their acquisition through lateral gene transfer. The epidemic-associated regions encode predicted prophage elements, pathogenicity islands, metabolic islands, fitness islands and genes of unknown functions, and 34 of the genes encoded in these regions were predicted as virulence factors. We found two pilus biogenesis gene clusters encoded within predicted pathogenicity islands. A functional metabolic island that encodes a complete pathway for myo-inositol catabolism was evident by the ability of epidemic A. hydrophila isolates to use myo-inositol as a sole carbon source. Testing of A. hydrophila field isolates found a consistent correlation between myo-inositol utilization as a sole carbon source and the presence of an epidemic-specific genetic marker. All epidemic isolates and one reference isolate shared a novel O-antigen cluster. Altogether we identified four different O-antigen biosynthesis gene clusters within the 11 sequenced A. hydrophila genomes. Our study reveals new insights into the evolutionary changes that have resulted in the emergence of recent epidemic A. hydrophila strains.

  15. Plasmid-mediated QnrS2 determinant in an Aeromonas caviae isolate recovered from a patient with diarrhoea.

    PubMed

    Arias, A; Seral, C; Navarro, F; Miró, E; Coll, P; Castillo, F J

    2010-07-01

    A qnrS2 gene was identified in an Aeromonas caviae isolate (MICs of ciprofloxacin, norfloxacin and ofloxacin >32 mg/L) from a stool sample collected from a patient with gastroenteritis. The analysis of the gyrA and parC genes revealed amino acid substitutions Ser83-Ile and Ser80-Thr, respectively. In addition, five out of 41 nalidixic acid-resistant Aeromonas isolates studied (26 identified as Aeromonas veronii bv sobria and 15 identified as A. caviae) showed ciprofloxacin resistance. The identification of plasmid-mediated qnr genes outside of the Enterobacteriaceae underlines a possible diffusion of these resistance determinants among Gram-negative rods. This emphasizes the importance of monitoring the emergence of these determinants as well as their dissemination among the Aeromonadaceae.

  16. Temperate bacteriophage {phi}O18P from an Aeromonas media isolate: Characterization and complete genome sequence

    SciTech Connect

    Beilstein, Frauke

    2008-03-30

    A group of 74 Aeromonas isolates from surface water of three ponds in Bielefeld, Germany was screened for prophage induction after UV irradiation. The phage {phi}O18P was induced from the Aeromonas media isolate O18. {phi}O18P belongs to the Myoviridae phage family. The complete nucleotide sequence of the double stranded DNA genome of bacteriophage {phi}O18P consists of 33,985 bp. The genome has 5' protruding cohesive ends of 16 bases. On the {phi}O18P genome 46 open reading frames (orfs) were identified which are organized in the modules integration and regulation, replication, head, packaging, tail and lysis. Additionally the phage DNA includes a methylase gene. Comparison of the genome architecture with those of other bacteriophages revealed significant similarities to the P2 phage family and especially to the prophages of Aeromonas salmonicida and the Vibrio cholerae phage K139.

  17. Distribution and phenotypic and genotypic detection of a metallo-β-lactamase, CphA, among bacteraemic Aeromonas isolates.

    PubMed

    Wu, Chi-Jung; Chen, Po-Lin; Wu, Jiunn-Jong; Yan, Jing-Jou; Lee, Chin-Chi; Lee, Hsin-Chun; Lee, Nan-Yao; Chang, Chia-Ming; Lin, Yu-Tzu; Chiu, Yen-Cheng; Ko, Wen-Chien

    2012-05-01

    The objectives of the study were to investigate the distribution of cphA-related genes (cphA) encoding a CphA metallo-β-lactamase (MBL) among 51 consecutive Aeromonas blood isolates and to compare different phenotypic methods for detecting CphA. The presence of cphA was detected by PCR. Four phenotypic methods, the imipenem-EDTA combined disc test, imipenem-EDTA MBL Etest, agar dilution test and modified Hodge test (MHT), were used to detect imipenem susceptibility and MBL production. The results showed that 35 (69%) blood isolates had cphA. All (100%) of 16 Aeromonas aquariorum isolates and 12 Aeromonas veronii isolates, and 4 (80%) of 5 Aeromonas hydrophila isolates, carried cphA, but none of 15 Aeromonas caviae isolates did. With the standard inocula, irrespective of the presence or absence of cphA, all but one (50, 98%) isolates were susceptible to imipenem tested by disc diffusion, Etest and agar dilution (10(4) c.f.u. spot inocula), and did not exhibit MBL production by the imipenem-EDTA combined disc test and MBL Etest. By the agar dilution test using large inocula (10(7) c.f.u.), 34 (97%) of 35 cphA(+) isolates had imipenem MICs of ≥16 µg ml(-1), higher than the susceptible breakpoint (4 µg ml(-1)), and demonstrated positive results for the MHT, while one cphA(+) and all 17 cphA(-) isolates had imipenem MICs of ≤4 µg ml(-1). In conclusion, the distribution of cphA among aeromonads is species-specific, found in A. aquariorum, A. veronii and A. hydrophila, and the MHT may be a phenotypic screening test for CphA production.

  18. Isolation and partial characterization of a virulent bacteriophage IHQ1 specific for Aeromonas punctata from stream water.

    PubMed

    Ul Haq, Irshad; Chaudhry, Waqas Nasir; Andleeb, Saadia; Qadri, Ishtiaq

    2012-05-01

    Aeromonas punctata is the causative agent of septicemia, diarrhea, wound infections, meningitis, peritonitis, and infections of the joints, bones and eyes. Bacteriophages are often considered alternative agents for controlling bacterial infection and contamination. In this study, we described the isolation and preliminary characterization of bacteriophage IHQ1 (family Myoviridae) active against the Gram-negative bacterial strain A. punctata. This virulent bacteriophage was isolated from stream water sample. Genome analysis indicated that phage IHQ1 was a double-stranded DNA virus with an approximate genome size of 25-28 kb. The initial characterization of this newly isolated phage showed that it has a narrow host range and infects only A. punctata as it failed to infect seven other clinically isolated pathogenic strains, i.e., methicillin-resistant Staphylococcus aureus 6403, MRSA 17644, Acinetobacter 33408, Acinetobacter 1172, Pseudomonas aeruginosa 22250, P. aeruginosa 11219, and Escherichia coli. Proteomic pattern of phage IHQ1, generated by SDS-PAGE using purified phage particles, showed three major and three minor protein bands with molecular weights ranging from 25 to 70 kDa. The adsorption rate of phage IHQ1 to the host bacterium was also determined, which was significantly enhanced by the addition of 10 mM CaCl(2). From the single-step growth experiment, it was inferred that the latent time period of phage IHQ1 was 24 min and a burst size of 626 phages per cell. Moreover, the pH and thermal stability of phage IHQ1 were also investigated. The maximum stability of the phage was observed at optimal pH 7.0, and it was totally unstable at extreme acidic pH 3; however, it was comparatively stable at alkaline pH 11.0. At 37°C the phage showed maximum number of plaques, and the viability was almost 100%. The existence of Aeromonas bacteriophage is very promising for the eradication of this opportunistic pathogen and also for future applications such as the

  19. Identification of unique DNA sequences present in highly virulent 2009 Alabama isolates of Aeromonas hydrophila.

    PubMed

    Pridgeon, Julia W; Klesius, Phillip H; Mu, Xingjiang; Carter, Dominique; Fleming, Kristen; Xu, Dehai; Srivastava, Kunwar; Reddy, Gopal

    2011-08-26

    In 2009, a disease outbreak caused by Aeromonas hydrophila occurred in 48 catfish farms in West Alabama, causing an estimated loss of more than 3 million pounds of food size channel catfish. Virulence studies have revealed that the 2009 isolates of A. hydrophila are at least 200-fold more virulent than a 1998 Alabama isolate AL98-C1B. However, up to now, no molecular markers have been identified to differentiate the highly virulent 2009 isolates from other isolates of A. hydrophila. To understand the genetic differences between the highly virulent 2009 isolates and the less virulent AL98-C1B at molecular level, PCR-select bacterial genome subtractive hybridization was used in this study. A total of 96 clones were selected from the subtractive genomic DNA library. Sequencing results revealed that the 96 clones represented 64 unique A. hydrophila sequences. Of the 64 sequences, three (hypothetical protein XAUC_13870, structural toxin protein RtxA, and putative methyltransferase) were confirmed to be present in the three virulent 2009 Alabama isolates but absent in the less virulent AL98-C1B. Using genomic DNAs from nine field isolates of A. hydrophila with different virulence as templates, two sequences (hypothetical protein XAUC_13870 and putative methyltransferase) were found to be only present in highly virulent A. hydrophila isolates, but absent in avirulent isolates.

  20. Structural determination of the O-specific polysaccharide from Aeromonas hydrophila strain A19 (serogroup O:14) with S-layer.

    PubMed

    Pieretti, Giuseppina; Carillo, Sara; Lanzetta, Rosa; Parrilli, Michelangelo; Merino, Susana; Tomás, Juan M; Corsaro, M Michela

    2011-11-01

    Bacteria belonging to the genus Aeromonas are Gram-negative mesophilic and essentially ubiquitous in the microbial biosphere; moreover they are considered very important pathogens in fish and responsible for a great variety of human infections. The virulence of Gram-negative bacteria is often associated with the structure of lipopolysaccharides, which consist of three regions covalently linked: the glycolipid (lipid A), the oligosaccharide region (core region) and the O-specific polysaccharide (O-chain, O-antigen). The O-chain region seems to play an important role in host-pathogen interaction. In the case of Aeromonas hydrophila the majority of pathogenic strains belongs to serogroups O:11, O:16, O:18 and O:34. In this paper, we report the complete structure of the O-chain of A. hydrophila strain A19 (serogroup O:14), a pathogenic strain isolated from European eels, which showed high virulence when tested in trout or mice. Dried cells were extracted by the PCP (phenol/chloroform/petroleum ether) method obtaining the lipopolysaccharide. After mild acid hydrolysis the lipid A was removed by centrifugation and the obtained polysaccharide was fully characterized by means of chemical analysis and one- and two-dimensional NMR spectroscopy. All the data collected are directed towards the following structure: [See formula in text].

  1. Predicting Virulence of Aeromonas Isolates Based-on Changes in Transcription of c-jun and c-fos in Human Tissue Culture Cells

    EPA Science Inventory

    Aims: To assess virulence of Aeromonas isolates based on the change in regulation of c-jun and c-fos in the human intestinal tissue culture cell line Caco-2. Methods and Results: Aeromonas cells were added to Caco-2 cells at approximately a one to one ratio. After 1, 2 and 3 ...

  2. Draft genome sequence of Pseudomonas mosselii Gil3, isolated from catfish and antagonistic against hypervirulent Aeromonas hydrophila

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas mosselii Gil3 was isolated from a catfish that survived from lethal challenge with hypervirulent Aeromonas hydrophila (vAh). When assayed in vitro, the bacterium showed antagonism against vAh. Sequence analysis revealed that the genome of P. mosselii Gil3 encodes numerous aromatic metabo...

  3. Degradation of chitin and chitosan by a recombinant chitinase derived from a virulent Aeromonas hydrophila isolated from diseased channel catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A chitinase was identified in extracellular products of a virulent Aeromonas hydrophila isolated from diseased channel catfish (Ictalurus punctatus). Bioactive recombinant chitinase (rChi-Ah) was produced in Escherichia coli. Purified rChi-Ah had optimal activity at temperature of 42°C and pH 6.5. T...

  4. Isolation and identification of two novel SDS-resistant secreted chitinases from Aeromonas schubertii

    PubMed Central

    Liu, Chao-Lin; Shen, Chia-Rui; Hsu, Fong-Fu; Chen, Jeen-Kuan; Wu, Pei-Tzu; Guo, Shang-Hsin; Lee, Wen-Chien; Yu, Feng-Wei; Mackey, Zachary B.; Turk, John; Gross, Michael L.

    2008-01-01

    Two SDS-resistant endochitinases, designated as ASCHI53 and ASCHI61, were isolated from Aeromonas schubertii in a soil sample from southern Taiwan. MALDI-TOF mass measurement indicates the molecular weights of 53,527 for ASCHI53 and 61,202 for ASCHI61. N-terminal and internal amino acid sequences were obtained, and BLAST analysis of the sequences and MS/MS peptide sequencing showed that they were novel proteins. Degradation of chitin by these two endochitinases gave rise to hexameric chitin oligosaccharide, a compound known to have several potent biomedical functions. ASCHI53 and ASCHI61 retained, respectively, 65% and 75%, of their chitinase activity in the presence of 5% SDS and 100% of their activity in the presence of 10% β-mercaptoethanol. These results demonstrate that they are SDS-resistant endochitinases and probably have a rigid structure. PMID:19197977

  5. Impact of stress on Aeromonas diversity in tambaqui (Colossoma macropomum) and lectin level change towards a bacterial challenge.

    PubMed

    Marques, Diego S C; Ferreira, Dijaci A; Paiva, Patrícia M G; Napoleão, Thiago H; Araújo, Janete M; Maciel Carvalho, Elba V M; Coelho, Luana C B B

    2016-12-01

    Tambaqui (Colossoma macropomum) is among the most cultivated fish species in tropical countries. Stress is the main cause of disease in fish farms. The genus Aeromonas is a common causative agent of fish diseases. This work reports the identification of Aeromonas species colonizing gills of C. macropomum submitted or not to a confinement stress. We also evaluated changes in serum levels of lectins (carbohydrate-binding proteins that are components of fish immune system) in tambaqui submitted to a challenge using two isolated Aeromonas strains. Gill tissues from stressed and unstressed fishes were used to isolate Aeromonas. Then 72 Aeromonas strains were isolated, 97% being from stressed fishes. Among these, 63 were identified at species level and 6 were classified as atypical Aeromonas strains. The most prevalent species were Aeromonas bestiarum and Aeromonas caviae and their strains were used in bacterial challenges. The lectin serum levels significantly increased after 24 h of infection with A. bestiarum; however, no significant increase was found for infection with A. caviae. In conclusion, C. macropomum gills are susceptible to colonization by different Aeromonas species, mainly at confinement stressful conditions, and serum lectins may have a role in the acute immunological response towards infection by A. bestiarum.

  6. Molecular identification and virulence of three Aeromonas hydrophila isolates cultured from infected channel catfish during a disease outbreak in west Alabama (USA) in 2009.

    PubMed

    Pridgeon, Julia W; Klesius, Phillip H

    2011-05-01

    Three isolates (AL09-71, AL09-72, and AL09-73) of Aeromonas hydrophila were cultured from infected channel catfish Ictalurus punctatus during a disease outbreak in west Alabama, USA, in August 2009. Sequence analysis of the 16S-23S rDNA intergenic spacer region (ISR), cpn60, gyrB, and rpoD genes of the 3 strains revealed that the 3 strains were closely related to each other, sharing 97 to 99% nucleotide sequence similarities. However, ISR sequences of the 3 isolates from 2009 shared only 64% nucleotide sequences with AL98-C1B, a 1998 isolate of A. hydrophila cultured from diseased fish in Alabama. Sequences of cpn60, gyrB, and rpoD from the 3 isolates from 2009 shared 91 to 95% homologies with AL98-C1B. Based on both LD50 and LD95 values of intraperitoneal injection assays, the virulences of the 3 isolates from 2009 were not significantly different from each other, but were at least 200-fold more virulent than AL98-C1B, indicating that the 3 west Alabama isolates of A. hydrophila from 2009 were highly virulent to channel catfish.

  7. Aeromonas detection and their toxins from drinking water from reservoirs and drinking fountains.

    PubMed

    Razzolini, Maria Tereza Pepe; Di Bari, Marisa; Sanchez, Petra Sanchez; Sato, Maria Inês Zanoli

    2008-03-01

    Aeromonads are inhabitants of aquatic ecosystems and are described as being involved in intestinal disturbances and other infections. A total of 200 drinking water samples from domestic and public reservoirs and drinking fountains located in São Paulo (Brazil), were analyzed for the presence of Aeromonas. Samples were concentrated by membrane filtration and enriched in APW. ADA medium was used for Aeromonas isolation and colonies were confirmed by biochemical characterization. Strains isolated were tested for hemolysin and toxin production. Aeromonas was detected in 12 samples (6.0%). Aeromonas strains (96) were isolated and identified as: A. caviae (41.7%), A. hydrophila (15.7%), A.allosacharophila (10.4%), A. schubertii (1.0%) and Aeromonas spp. (31.2%). The results revealed that 70% of A. caviae, 66.7% of A. hydrophila, 80% of A. allosacharophila and 46.6% of Aeromonas spp. were hemolytic. The assay for checking production of toxins showed that 17.5% of A. caviae, 73.3% of A. hydrophila, 60% of A. allosacharophila, 100% of A. schubertii, and 33.3% of Aeromonas spp. were able to produce toxins. The results demonstrated the pathogenic potential of Aeromonas, indicating that the presence of this emerging pathogen in water systems is a public health concern.

  8. Reassessment of the Enteropathogenicity of Mesophilic Aeromonas Species

    PubMed Central

    Teunis, Peter; Figueras, Maria J.

    2016-01-01

    Cases of Aeromonas diarrhea have been described all over the world. The genus Aeromonas includes ca. 30 species, of which 10 have been isolated in association with gastroenteritis. The dominating species that account for ca. 96% of the identified strains are Aeromonas caviae, A. veronii, A. dhakensis, and A. hydrophila. However, the role of Aeromonas as a true enteropathogen has been questioned on the basis of the lack of outbreaks, the non-fulfillment of Koch’s postulates and the low numbers of acute illnesses in the only existing human challenge study. In the present study we reassess the enteropathogenicity of Aeromonas using dose response models for microbial infection and acute illness. The analysis uses the data from the human challenge study and additional data from selected outbreak investigations where the numbers exposed and the dose were reported, allowing their inclusion as “natural experiments”. In the challenge study several cases of asymptomatic shedding were found (26.3%, 15/57), however, only 3.5% (2/57) of those challenged with Aeromonas developed acute enteric symptoms (i.e., diarrhea). The “natural experiments” showed a much higher risk of illness associated with exposure to Aeromonas, even at moderate to low doses. The median dose required for 1% illness risk, was ~1.4 × 104 times higher in the challenge study (1.24 × 104 cfu) compared to natural exposure events (0.9 cfu). The dose response assessment presented in this study shows that the combined challenge and outbreak data are consistent with high infectivity of Aeromonas, and a wide range of susceptibility to acute enteric illness. To illustrate the outcomes, we simulate the risk associated with concentrations of Aeromonas found in different water and food matrices, indicating the disease burden potentially associated with these bacteria. In conclusion this study showed that Aeromonas is highly infectious, and that human susceptibility to illness may be high, similar to

  9. Molecular Basis of Sulfonamide and Trimethoprim Resistance in Fish-Pathogenic Aeromonas Isolates

    PubMed Central

    Kadlec, Kristina; von Czapiewski, Ellen; Kaspar, Heike; Wallmann, Jürgen; Michael, Geovana Brenner; Steinacker, Ulrike; Schwarz, Stefan

    2011-01-01

    Sulfonamide-trimethoprim-resistant Aeromonas salmonicida and motile Aeromonas spp. from diseased fish of the GERM-Vet study carried the sul1 gene together with mostly cassette-borne trimethoprim resistance genes, including the novel gene dfrA28. The seven dfrA and dfrB genes identified were located mostly in class 1 integrons which commonly harbored other gene cassettes. PMID:21764945

  10. Effectiveness of radiation processing in elimination of Aeromonas from food

    NASA Astrophysics Data System (ADS)

    Nagar, Vandan; Bandekar, Jayant R.

    2011-08-01

    Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Contaminated water, sprouts, vegetables, seafood and food of animal origin have been considered to be the important sources of Aeromonas infection. In the present study, radiation sensitivity of indigenous strains of Aeromonas spp. from different food samples was evaluated. The decimal reduction dose (D10) values of different Aeromonas isolates in saline at 0-4 °C were in the range of 0.031-0.046 kGy. The mixed sprouts, chicken and fish samples were inoculated with a cocktail of five most resistant isolates (A. salmonicida Y567, A. caviae A85, A. jandaei A514A, A. hydrophila CECT 839T and A. veronii Y47) and exposed to γ radiation to study the effectiveness of radiation treatment in elimination of Aeromonas. D10 values of Aeromonas cocktail in mixed sprouts, chicken and fish samples were found to be 0.081±0.001, 0.089±0.003 and 0.091±0.003 kGy, respectively. Radiation treatment with a 1.5 kGy dose resulted in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples. No recovery of Aeromonas was observed in the 1.5 kGy treated samples stored at 4 °C up to 12 (mixed sprouts) and 7 days (chicken and fish samples), even after enrichment and selective plating. This study demonstrates that a 1.5 kGy dose of irradiation treatment could result in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples.

  11. The improved PCR of the fstA (ferric siderophore receptor) gene differentiates the fish pathogen Aeromonas salmonicida from other Aeromonas species.

    PubMed

    Beaz-Hidalgo, Roxana; Latif-Eugenín, Fadua; Figueras, María José

    2013-10-25

    The members of the genus Aeromonas are autochthonous of aquatic ecosystems and several species have been associated to septicaemia, ulcerative and haemorrhagic diseases in fish, causing significant mortality in both wild and farmed, freshwater and marine fish species. The species Aeromonas salmonicida is generally recognized as the most important fish pathogen responsible for epidemic outbreaks of furunculosis in salmonids, also being able to produce infections in other cultured fish such as turbot, halibut, sea bream or goldfish. New species, i.e. Aeromonas aquariorum, Aeromonas tecta and Aeromonas piscicola, have recently been discovered and isolated from diseased fish. The species A. piscicola and Aeromonas bestiarum are practically impossible to differentiate phenotypically and genetically (when using the 16S rRNA gene) from each other and from A. salmonicida. In the present study, two previously described PCR protocols, based on the fstA and gyrB genes, for the specific detection of A. salmonicida were re-evaluated with the type strains of all Aeromonas species and with a set of A. piscicola and A. bestiarum strains. Contrary to what had been published previously it was demonstrated that the gyrB-PCR is not specific for A. salmonicida because of cross-reactions with other Aeromonas species. However, in agreement with previous results, A. salmonicida was detected on the basis of the fstA-PCR, for which an improved protocol was proposed. PMID:23890674

  12. Chironomid egg masses harbour the clinical species Aeromonas taiwanensis and Aeromonas sanarellii.

    PubMed

    Beaz-Hidalgo, Roxana; Shakèd, Tamar; Laviad, Sivan; Halpern, Malka; Figueras, María J

    2012-12-01

    Bacteria of the genus Aeromonas are found worldwide in aquatic environments and may produce human infections. In 2010, two new clinical species, Aeromonas sanarellii and Aeromonas taiwanensis, were described on the basis of one strain recovered from wounds of hospitalized patients in Taiwan. So far, only four environmental isolates of A. sanarellii and one of A. taiwanensis have been recorded from waste water in Portugal and an additional clinical strain of A. taiwanensis from the faeces of a patient with diarrhoea in Israel. In the present study, strains belonging to these two species were identified from chironomid egg masses from the same area in Israel by sequencing the rpoD gene. This represents a new environmental habitat for these novel species. The first data on the virulence genes and antibiotic susceptibility are provided. The isolates of these two new species possess multiple virulence genes and are sensitive to amikacin, aztreonam, cefepime, cefoxatime, ceftazidime, ciprofloxacin, gentamicin, piperacillin-tazobactam, tigecycline, tobramycin, trimethoprim-sulfamethoxazole and imipenem. The key phenotypic tests for the differentiation of these new species from their closest relative Aeromonas caviae included the utilization of citrate, growth at 45 °C in sheep blood agar and acid production of cellobiose.

  13. Medicinal leech therapy and Aeromonas spp. infection.

    PubMed

    Verriere, B; Sabatier, B; Carbonnelle, E; Mainardi, J L; Prognon, P; Whitaker, I; Lantieri, L; Hivelin, M

    2016-06-01

    While the use of medicinal leech therapy (MLT) in reconstructive and orthopaedic surgery is widely described, post-operative complications related to leeches remain a major concern. Aeromonas spp. strains are involved in the majority of reported cases. As surgical success rate is directly impacted, an adapted antibiotic prophylaxis should be instituted in order to minimize these complications. We assessed pharmaceutical process, microbiological control and related infections in order to provide data and choose the appropriate antibiotherapy for patients requiring MLT. We report a clinical and microbiological study over a 24-month period. Clinical data were collected from patients' database, and microbiological analysis both on leeches' tank water and crushed leeches were performed to characterize isolated strains and their susceptibility to antibiotics. A total of 595 leeches were used to treat 28 patients (12 in plastic surgery and 16 in orthopaedic surgery), and three documented cases of post-operative infections were reported. Aeromonas spp. isolates yielded from 62 % of analyzed batches (75 % of Aeromonas veronii). Eighteen Aeromonas spp. isolates yielded from 23 water samples and three crushed leeches. Isolates were similar in tank and crushed leeches. Strains were susceptible to fluoroquinolones, sulfamethoxazole/trimethoprim, aminosides, and third-generation cephalosporins but resistant to amoxicillin/clavulanic acid and second-generation cephalosporins. According to collected data, routine tank water microbiological analyses are mandatory in order to identify leeches' batches containing resistant strains and to discard them. In this context, the surgeon is able to select an appropriated antibiotic prophylaxis in order to avoid MLT associated serious post-operative complications.

  14. Genome sequence of the emerging pathogen Aeromonas caviae.

    PubMed

    Beatson, Scott A; das Graças de Luna, Maria; Bachmann, Nathan L; Alikhan, Nabil-Fareed; Hanks, Kirstin R; Sullivan, Mitchell J; Wee, Bryan A; Freitas-Almeida, Angela C; Dos Santos, Paula A; de Melo, Janyne T B; Squire, Derrick J P; Cunningham, Adam F; Fitzgerald, J Ross; Henderson, Ian R

    2011-03-01

    Aeromonas caviae is a Gram-negative, motile and rod-shaped facultative anaerobe that is increasingly being recognized as a cause of diarrhea in children. Here we present the first genome sequence of an A. caviae strain that was isolated as the sole pathogen from a child with profuse diarrhea.

  15. Draft Genome Sequence of Aeromonas hydrophila TN97-08

    PubMed Central

    Tekedar, Hasan C.; Kumru, Salih; Karsi, Attila; Waldbieser, Geoffrey C.; Sonstegard, Tad; Schroeder, Steven G.; Liles, Mark R.; Griffin, Matt J.

    2016-01-01

    Aeromonas hydrophila is an opportunistic pathogen residing in freshwater environments that causes infection in fish and mammals. Here, we report the draft genome sequence of A. hydrophila strain TN97-08 isolated from a diseased bluegill (Lepomis macrochirus) in 1997. PMID:27231367

  16. Aeromonas chitinase degrades chironomid egg masses.

    PubMed

    Laviad, Sivan; Golan, Amnon; Shaked, Tamar; Vaizel-Ohayon, Dalit; Halpern, Malka; Pick, Elah

    2016-02-01

    Chironomids are freshwater insects that undergo a complete metamorphosis of four life stages. Chironomid egg masses can be degraded by Vibrio cholerae and some Aeromonas species. Egg mass degradation by V. cholerae requires haemagglutinin protease activity. Our aim was to identify the egg mass degrading (EMD) factor secreted by Aeromonas dhkanesis 3K1C15. Following the hypothesis that the EMD factor of A. dhkanesis is also a protease, secreted proteases were screened, but none of them proved to have the same properties as the EMD factor. Using conventional protein purification methods, we found that the active fraction included chitinases. We further confirmed chitin as a building block of the egg masses. Interestingly, by supplementing bacterial growth media with chitin, we observed unexpected EMD factor activity in Aeromonas isolates that initially were not able to degrade egg masses. Accordingly, we concluded that although strain 3K1C15 secretes chitinases constitutively, most Aeromonas strains secrete chitinases inductively. Induction of chitinases in nature presumably occurs when bacteria are attached to the egg mass habitat, in which chitin is abundant. Considering that chitinases are highly conserved across bacteria phyla, we assume that the role of this enzyme in the bacteria-insect interplay could be wider than is currently thought. PMID:26472256

  17. Biochemical and molecular characterization of the novobiocin and rifampicin resistant Aeromonas hydrophila vaccine strain AL09-71 N+R compared to its virulent parent strain AL90-71

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To understand the fitness cost of novobiocin- and rifampicin- resistance in an attenuated Aeromonas hydrophiila vaccine strain AL09-71 N+R compared to its virulent parent strain AL09-71, colony size, cell size, cell proliferation rate, chemotactic response, and the ability to invade catfish gill cel...

  18. Identification of gyrB and rpoB gene mutations and differentially expressed proteins between a novobiocin-resistant Aeromonas hydrophila catfish vaccine strain and its virulent parent strain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sequence comparison between the full-length 2412 bp DNA gyrase subunit B (gyrB) gene of a novobiocin resistant Aeromonas hydrophila AH11NOVO vaccine strain and that of its virulent parent strain AH11P revealed 10 missense mutations. Similarly, sequence comparison between the full-length 4092 bp RNA ...

  19. Identification, virulence, and mass spectrometry of toxic ECP fractions of West Alabama isolates of Aeromonas hydrophila obtained from a 2010 disease outbreak.

    PubMed

    Pridgeon, Julia W; Klesius, Phillip H; Song, Lin; Zhang, Dunhua; Kojima, Kyoko; Mobley, James A

    2013-06-28

    In West Alabama, disease outbreaks in 2009 caused by Aeromonas hydrophila have led to an estimated loss of more than $3 million. In 2010, disease outbreak occurred again in West Alabama, causing losses of hundreds of thousands of pounds of market size channel catfish. During the 2010 disease outbreak in West Alabama, four isolates of A. hydrophila were cultured from the kidney tissues of diseased channel catfish. Both analytical profile index (API) 20 E biochemical tests and 16S-23S rRNA sequencing results confirmed the four isolates as A. hydrophila. Virulence studies revealed that the four isolates were highly virulent to channel catfish by intraperitoneal injection, with LD50 value of ≈ 1.3 × 10(5)CFU/fish. Extracellular proteins (ECPs) of A. hydrophila are well known to be toxic to fish. Therefore, ECPs of the four 2010 West Alabama isolates of A. hydrophila were characterized in this study. The ECPs of the four 2010 isolates were found to be toxic to channel catfish fingerlings, with LD50 value of 16 μg/fish. Thirty ECP fractions were obtained from the ECPs of the 2010 isolates of A. hydrophila by cation-exchange chromatography, of which nine fractions were found to be toxic to catfish gill cells and channel catfish fingerlings. Mass spectrometry identified 228 proteins from the nine toxic fractions, of which 23 were shared by toxic fractions, including well known virulence factors such as hemolysin, aerolysin, elastase (metalloprotease), nuclease, and 5'-nucleotidase. Hemolytic activity, protease activity, and nuclease activity of the four isolates were found to be significantly (P<0.05) higher than that of a reference A. hydrophila strain AL98-C1B. Our results might shed light on the possible virulence factors of the highly virulent West Alabama isolates of A. hydrophila.

  20. High prevalence of blaCTX-M group genes in Aeromonas dhakensis isolated from aquaculture fish species in South Korea.

    PubMed

    Yi, Seung-Won; Chung, Tae-Ho; Joh, Seong-Joon; Park, Chul; Park, Byoung-Yong; Shin, Gee-Wook

    2014-12-01

    The prevalence of resistant genes against β-lactams in 119 Aeromonas strains was determined. A large number (99.2%) of the present fish strains were resistant to one or more β- lactams including ceftiofur, amoxicillin-clavulanic acid, ampicillin, piperacillin and cefpodoxime. Among antibiotic resistance phenotypes, the simultaneous resistance to all β-lactams occurred in 25.2% (n=30) of all strains, which consisted of 18 strains of A. dhakensis, 8 strains of A. caviae, 2 strains of A. hydrophila and only one strain of A. veronii. For exploring genetic background of the antibiotic resistances, multiple PCR assays were subjected to detect β-lactamase-encoding genes, bla(TEM), bla(OXA-B) and bla(CTX-M). In the results, the bla(TEM-1) gene was harbored in all strains, whereas only 3 strains harbored bla(OXA) gene. In the case of bla(CTX-M) gene, the gene was detected in 21.0% (25 out of 119) of all strains, which countered with 80% (20 out of 25) of A. dhakensis, 8% (2 out of 25) of A. caviae and 12% (3 out of 25) of A. hydrophila. In addition, most of the bla(CTX-M) positive strains showed simultaneous resistance to all β-lactams (18 out of 30 strains). In sequence analysis for bla(CTX-M) genes detected, they were CTX-M group 1-encoding genes including bla(CTX-M-33) from 3 eel strains of A. dhakensis. Therefore, A. dhakensis obtained from cultured fish could represent a reservoir for spreading genes encoding CTX-M group 1 enzymes and hence should be carefully monitored, especially for its potential risk to public health.

  1. Cross-talk among flesh-eating Aeromonas hydrophila strains in mixed infection leading to necrotizing fasciitis

    PubMed Central

    Ponnusamy, Duraisamy; Kozlova, Elena V.; Sha, Jian; Erova, Tatiana E.; Azar, Sasha R.; Fitts, Eric C.; Kirtley, Michelle L.; Tiner, Bethany L.; Andersson, Jourdan A.; Grim, Christopher J.; Isom, Richard P.; Hasan, Nur A.; Colwell, Rita R.; Chopra, Ashok K.

    2016-01-01

    Necrotizing fasciitis (NF) caused by flesh-eating bacteria is associated with high case fatality. In an earlier study, we reported infection of an immunocompetent individual with multiple strains of Aeromonas hydrophila (NF1–NF4), the latter three constituted a clonal group whereas NF1 was phylogenetically distinct. To understand the complex interactions of these strains in NF pathophysiology, a mouse model was used, whereby either single or mixed A. hydrophila strains were injected intramuscularly. NF2, which harbors exotoxin A (exoA) gene, was highly virulent when injected alone, but its virulence was attenuated in the presence of NF1 (exoA-minus). NF1 alone, although not lethal to animals, became highly virulent when combined with NF2, its virulence augmented by cis-exoA expression when injected alone in mice. Based on metagenomics and microbiological analyses, it was found that, in mixed infection, NF1 selectively disseminated to mouse peripheral organs, whereas the other strains (NF2, NF3, and NF4) were confined to the injection site and eventually cleared. In vitro studies showed NF2 to be more effectively phagocytized and killed by macrophages than NF1. NF1 inhibited growth of NF2 on solid media, but ExoA of NF2 augmented virulence of NF1 and the presence of NF1 facilitated clearance of NF2 from animals either by enhanced priming of host immune system or direct killing via a contact-dependent mechanism. PMID:26733683

  2. Cross-talk among flesh-eating Aeromonas hydrophila strains in mixed infection leading to necrotizing fasciitis.

    PubMed

    Ponnusamy, Duraisamy; Kozlova, Elena V; Sha, Jian; Erova, Tatiana E; Azar, Sasha R; Fitts, Eric C; Kirtley, Michelle L; Tiner, Bethany L; Andersson, Jourdan A; Grim, Christopher J; Isom, Richard P; Hasan, Nur A; Colwell, Rita R; Chopra, Ashok K

    2016-01-19

    Necrotizing fasciitis (NF) caused by flesh-eating bacteria is associated with high case fatality. In an earlier study, we reported infection of an immunocompetent individual with multiple strains of Aeromonas hydrophila (NF1-NF4), the latter three constituted a clonal group whereas NF1 was phylogenetically distinct. To understand the complex interactions of these strains in NF pathophysiology, a mouse model was used, whereby either single or mixed A. hydrophila strains were injected intramuscularly. NF2, which harbors exotoxin A (exoA) gene, was highly virulent when injected alone, but its virulence was attenuated in the presence of NF1 (exoA-minus). NF1 alone, although not lethal to animals, became highly virulent when combined with NF2, its virulence augmented by cis-exoA expression when injected alone in mice. Based on metagenomics and microbiological analyses, it was found that, in mixed infection, NF1 selectively disseminated to mouse peripheral organs, whereas the other strains (NF2, NF3, and NF4) were confined to the injection site and eventually cleared. In vitro studies showed NF2 to be more effectively phagocytized and killed by macrophages than NF1. NF1 inhibited growth of NF2 on solid media, but ExoA of NF2 augmented virulence of NF1 and the presence of NF1 facilitated clearance of NF2 from animals either by enhanced priming of host immune system or direct killing via a contact-dependent mechanism. PMID:26733683

  3. Cross-talk among flesh-eating Aeromonas hydrophila strains in mixed infection leading to necrotizing fasciitis.

    PubMed

    Ponnusamy, Duraisamy; Kozlova, Elena V; Sha, Jian; Erova, Tatiana E; Azar, Sasha R; Fitts, Eric C; Kirtley, Michelle L; Tiner, Bethany L; Andersson, Jourdan A; Grim, Christopher J; Isom, Richard P; Hasan, Nur A; Colwell, Rita R; Chopra, Ashok K

    2016-01-19

    Necrotizing fasciitis (NF) caused by flesh-eating bacteria is associated with high case fatality. In an earlier study, we reported infection of an immunocompetent individual with multiple strains of Aeromonas hydrophila (NF1-NF4), the latter three constituted a clonal group whereas NF1 was phylogenetically distinct. To understand the complex interactions of these strains in NF pathophysiology, a mouse model was used, whereby either single or mixed A. hydrophila strains were injected intramuscularly. NF2, which harbors exotoxin A (exoA) gene, was highly virulent when injected alone, but its virulence was attenuated in the presence of NF1 (exoA-minus). NF1 alone, although not lethal to animals, became highly virulent when combined with NF2, its virulence augmented by cis-exoA expression when injected alone in mice. Based on metagenomics and microbiological analyses, it was found that, in mixed infection, NF1 selectively disseminated to mouse peripheral organs, whereas the other strains (NF2, NF3, and NF4) were confined to the injection site and eventually cleared. In vitro studies showed NF2 to be more effectively phagocytized and killed by macrophages than NF1. NF1 inhibited growth of NF2 on solid media, but ExoA of NF2 augmented virulence of NF1 and the presence of NF1 facilitated clearance of NF2 from animals either by enhanced priming of host immune system or direct killing via a contact-dependent mechanism.

  4. Comparison of MALDI-TOF MS, Housekeeping Gene Sequencing, and 16S rRNA Gene Sequencing for Identification of Aeromonas Clinical Isolates

    PubMed Central

    Shin, Hee Bong; Yoon, Jihoon; Lee, Yangsoon; Kim, Myung Sook

    2015-01-01

    Purpose The genus Aeromonas is a pathogen that is well known to cause severe clinical illnesses, ranging from gastroenteritis to sepsis. Accurate identification of A. hydrophila, A. caviae, and A. veronii is important for the care of patients. However, species identification remains difficult using conventional methods. The aim of this study was to compare the accuracy of different methods of identifying Aeromonas at the species level: a biochemical method, matrix-assisted laser desorption ionization mass spectrometry-time of flight (MALDI-TOF MS), 16S rRNA sequencing, and housekeeping gene sequencing (gyrB, rpoB). Materials and Methods We analyzed 65 Aeromonas isolates recovered from patients at a university hospital in Korea between 1996 and 2012. The isolates were recovered from frozen states and tested using the following four methods: a conventional biochemical method, 16S rRNA sequencing, housekeeping gene sequencing with phylogenetic analysis, and MALDI-TOF MS. Results The conventional biochemical method and 16S rRNA sequencing identified Aeromonas at the genus level very accurately, although species level identification was unsatisfactory. MALDI-TOF MS system correctly identified 60 (92.3%) isolates at the species level and an additional four (6.2%) at the genus level. Overall, housekeeping gene sequencing with phylogenetic analysis was found to be the most accurate in identifying Aeromonas at the species level. Conclusion The most accurate method of identification of Aeromonas to species level is by housekeeping gene sequencing, although high cost and technical difficulty hinder its usage in clinical settings. An easy-to-use identification method is needed for clinical laboratories, for which MALDI-TOF MS could be a strong candidate. PMID:25684008

  5. Complete Genome Sequence of the Highly Virulent Aeromonas hydrophila AL09-71 Isolated from Diseased Channel Catfish in West Alabama.

    PubMed

    Pridgeon, Julia W; Zhang, Dunhua; Zhang, Lee

    2014-05-22

    Aeromonas hydrophila AL09-71 was isolated from diseased channel catfish in west Alabama during a 2009 disease outbreak. The full genome of A. hydrophila AL09-71 is 5,023,861 bp. The availability of this genome will allow comparative genomics to identify genes involved in pathogenesis or immunogens for the purpose of vaccine development.

  6. Polar Glycosylated and Lateral Non-Glycosylated Flagella from Aeromonas hydrophila Strain AH-1 (Serotype O11)

    PubMed Central

    Fulton, Kelly M.; Mendoza-Barberá, Elena; Twine, Susan M.; Tomás, Juan M.; Merino, Susana

    2015-01-01

    Polar and but not lateral flagellin proteins from Aeromonas hydrophila strain AH-1 (serotype O11) were found to be glycosylated. Top-down mass spectrometry studies of purified polar flagellins suggested the presence of a 403 Da glycan of mass. Bottom-up mass spectrometry studies showed the polar flagellin peptides to be modified with 403 Da glycans in O-linkage. The MS fragmentation pattern of this putative glycan was similar to that of pseudaminic acid derivative. Mutants lacking the biosynthesis of pseudaminic acid (pseB and pseI homologues) were unable to produce polar flagella but no changes were observed in lateral flagella by post-transcriptional regulation of the flagellin. Complementation was achieved by reintroduction of the wild-type pseB and pseI. We compared two pathogenic features (adhesion to eukaryotic cells and biofilm production) between the wild-type strain and two kinds of mutants: mutants lacking polar flagella glycosylation and lacking the O11-antigen lipopolysaccharide (LPS) but with unaltered polar flagella glycosylation. Results suggest that polar flagella glycosylation is extremely important for A. hydrophila AH-1 adhesion to Hep-2 cells and biofilm formation. In addition, we show the importance of the polar flagella glycosylation for immune stimulation of IL-8 production via toll-“like” receptor 5 (TLR5). PMID:26633358

  7. Polar Glycosylated and Lateral Non-Glycosylated Flagella from Aeromonas hydrophila Strain AH-1 (Serotype O11).

    PubMed

    Fulton, Kelly M; Mendoza-Barberá, Elena; Twine, Susan M; Tomás, Juan M; Merino, Susana

    2015-01-01

    Polar and but not lateral flagellin proteins from Aeromonas hydrophila strain AH-1 (serotype O11) were found to be glycosylated. Top-down mass spectrometry studies of purified polar flagellins suggested the presence of a 403 Da glycan of mass. Bottom-up mass spectrometry studies showed the polar flagellin peptides to be modified with 403 Da glycans in O-linkage. The MS fragmentation pattern of this putative glycan was similar to that of pseudaminic acid derivative. Mutants lacking the biosynthesis of pseudaminic acid (pseB and pseI homologues) were unable to produce polar flagella but no changes were observed in lateral flagella by post-transcriptional regulation of the flagellin. Complementation was achieved by reintroduction of the wild-type pseB and pseI. We compared two pathogenic features (adhesion to eukaryotic cells and biofilm production) between the wild-type strain and two kinds of mutants: mutants lacking polar flagella glycosylation and lacking the O11-antigen lipopolysaccharide (LPS) but with unaltered polar flagella glycosylation. Results suggest that polar flagella glycosylation is extremely important for A. hydrophila AH-1 adhesion to Hep-2 cells and biofilm formation. In addition, we show the importance of the polar flagella glycosylation for immune stimulation of IL-8 production via toll-"like" receptor 5 (TLR5). PMID:26633358

  8. Polar Glycosylated and Lateral Non-Glycosylated Flagella from Aeromonas hydrophila Strain AH-1 (Serotype O11).

    PubMed

    Fulton, Kelly M; Mendoza-Barberá, Elena; Twine, Susan M; Tomás, Juan M; Merino, Susana

    2015-01-01

    Polar and but not lateral flagellin proteins from Aeromonas hydrophila strain AH-1 (serotype O11) were found to be glycosylated. Top-down mass spectrometry studies of purified polar flagellins suggested the presence of a 403 Da glycan of mass. Bottom-up mass spectrometry studies showed the polar flagellin peptides to be modified with 403 Da glycans in O-linkage. The MS fragmentation pattern of this putative glycan was similar to that of pseudaminic acid derivative. Mutants lacking the biosynthesis of pseudaminic acid (pseB and pseI homologues) were unable to produce polar flagella but no changes were observed in lateral flagella by post-transcriptional regulation of the flagellin. Complementation was achieved by reintroduction of the wild-type pseB and pseI. We compared two pathogenic features (adhesion to eukaryotic cells and biofilm production) between the wild-type strain and two kinds of mutants: mutants lacking polar flagella glycosylation and lacking the O11-antigen lipopolysaccharide (LPS) but with unaltered polar flagella glycosylation. Results suggest that polar flagella glycosylation is extremely important for A. hydrophila AH-1 adhesion to Hep-2 cells and biofilm formation. In addition, we show the importance of the polar flagella glycosylation for immune stimulation of IL-8 production via toll-"like" receptor 5 (TLR5).

  9. Prevalence and resistance to antibiotics for Aeromonas species from retail fish in Malaysia.

    PubMed

    Radu, Son; Ahmad, Noorlis; Ling, Foo Hooi; Reezal, Abdul

    2003-03-25

    A total of 87 market fish samples representing five types of fish were evaluated for the presence of Aeromonas spp. Of the samples examined, 69%, 55%, 11.5% and 2.3% harbored Aeromonas spp., A. veronii biovar sobria, A. hydrophila and A. caviae, respectively. The 60 isolated Aeromonas spp. strains were further examined for hemolytic activity, resistance to antimicrobial agents and presence of plasmids. Hemolytic activity varied widely among the isolated strains. Though all the isolates demonstrated resistance to three or more of the antibiotics tested, all were susceptible to ceptazidime. Thirty-four (56.7%) of the sixty isolates harbored plasmids, with sizes ranging from 2.3 to 15.7 kb. These results indicate that hemolytic, multiple antibiotic resistant and genetically diverse aeromonads are easily recovered from fish in this region. PMID:12485753

  10. Prevalence and resistance to antibiotics for Aeromonas species from retail fish in Malaysia.

    PubMed

    Radu, Son; Ahmad, Noorlis; Ling, Foo Hooi; Reezal, Abdul

    2003-03-25

    A total of 87 market fish samples representing five types of fish were evaluated for the presence of Aeromonas spp. Of the samples examined, 69%, 55%, 11.5% and 2.3% harbored Aeromonas spp., A. veronii biovar sobria, A. hydrophila and A. caviae, respectively. The 60 isolated Aeromonas spp. strains were further examined for hemolytic activity, resistance to antimicrobial agents and presence of plasmids. Hemolytic activity varied widely among the isolated strains. Though all the isolates demonstrated resistance to three or more of the antibiotics tested, all were susceptible to ceptazidime. Thirty-four (56.7%) of the sixty isolates harbored plasmids, with sizes ranging from 2.3 to 15.7 kb. These results indicate that hemolytic, multiple antibiotic resistant and genetically diverse aeromonads are easily recovered from fish in this region.

  11. Surface protein composition of Aeromonas hydrophila strains virulent for fish: identification of a surface array protein

    SciTech Connect

    Dooley, J.S.G.; Trust, T.J.

    1988-02-01

    The surface protein composition of members of a serogroup of Aeromonas hydrophila was examined. Immunoblotting with antiserum raised against formalinized whole cells of A. hydrophila TF7 showed a 52K S-layer protein to be the major surface protein antigen, and impermeant Sulfo-NHS-Biotin cell surface labeling showed that the 52K S-layer protein was the only protein accessible to the Sulfo-NHS-Biotin label and effectively masked underlying outer membrane (OM) proteins. In its native surface conformation the 52K S-layer protein was only weakly reactive with a lactoperoxidase /sup 125/I surface iodination procedure. A UV-induced rough lipopolysaccharide (LPS) mutant of TF7 was found to produce an intact S layer, but a deep rough LPS mutant was unable to maintain an array on the cell surface and excreted the S-layer protein into the growth medium, indicating that a minimum LPS oligosaccharide size required for A. hydrophila S-layer anchoring. The native S layer was permeable to /sup 125/I in the lactoperoxidase radiolabeling procedure, and two major OM proteins of molecular weights 30,000 and 48,000 were iodinated. The 48K species was a peptidoglycan-associated, transmembrane protein which exhibited heat-modifiable SDS solubilization behavior characteristic of a porin protein. A 50K major peptidoglycan-associated OM protein which was not radiolabeled exhibited similar SDS heat modification characteristics and possibly represents a second porin protein.

  12. Decolorization of the textile dyes by newly isolated bacterial strains.

    PubMed

    Chen, Kuo-Cheng; Wu, Jane-Yii; Liou, Dar-Jen; Hwang, Sz-Chwun John

    2003-02-27

    Six bacterial strains with the capability of degrading textile dyes were isolated from sludge samples and mud lakes. Aeromonas hydrophila was selected and identified because it exhibited the greatest color removal from various dyes. Although A. hydrophila displayed good growth in aerobic or agitation culture (AGI culture), color removal was the best in anoxic or anaerobic culture (ANA culture). For color removal, the most suitable pH and temperature were pH 5.5-10.0 and 20-35 degrees C under anoxic culture (ANO culture). More than 90% of RED RBN was reduced in color within 8 days at a dye concentration of 3,000 mg l(-1). This strain could also decolorize the media containing a mixture of dyes within 2 days of incubation. Nitrogen sources such as yeast extract or peptone could enhance strongly the decolorization efficiency. In contrast to a nitrogen source, glucose inhibited decolorization activity because the consumed glucose was converted to organic acids that might decrease the pH of the culture medium, thus inhibiting the cell growth and decolorization activity. Decolorization appeared to proceed primarily by biological degradation.

  13. Antibiotic Resistance in Aeromonas Upstream and Downstream of a Water Resource Recovery Facility

    PubMed Central

    Henderson, Samantha K.; Askew, Maegan L.; Risenhoover, Hollie G.; McAndrews, Chrystle R.; Kennedy, S. Dawn; Paine, C. Sue

    2014-01-01

    Aeromonas strains isolated from sediments upstream and downstream of a water resource recovery facility (WRRF) over a two-year time period were tested for susceptibility to thirteen antibiotics. Incidence of resistance to antibiotics, antibiotic resistance phenotypes, and diversity (based on resistance phenotypes) were compared in the two populations. At the beginning of the study, the upstream and downstream Aeromonas populations were different for incidence of antibiotic resistance (p < 0.01), resistance phenotypes (p < 0.005), and diversity. However, these differences declined over time and were not significant at the end of the study. These results (1) indicate that antibiotic resistance in Aeromonas in stream sediments fluctuates considerably over time and (2) suggest that WRRF effluent does not, when examined over the long term, affect antibiotic resistance in Aeromonas in downstream sediment. PMID:25327024

  14. Antibiotic resistance in Aeromonas upstream and downstream of a water resource recovery facility.

    PubMed

    Cisar, Cindy R; Henderson, Samantha K; Askew, Maegan L; Risenhoover, Hollie G; McAndrews, Chrystle R; Kennedy, S Dawn; Paine, C Sue

    2014-09-01

    Aeromonas strains isolated from sediments upstream and downstream of a water resource recovery facility (WRRF) over a two-year time period were tested for susceptibility to 13 antibiotics. Incidence of resistance to antibiotics, antibiotic resistance phenotypes, and diversity (based on resistance phenotypes) were compared in the two populations. At the beginning of the study, the upstream and downstream Aeromonas populations were different for incidence of antibiotic resistance (p < 0.01), resistance phenotypes (p < 0.005), and diversity. However, these differences declined over time and were not significant at the end of the study. These results (1) indicate that antibiotic resistance in Aeromonas in stream sediments fluctuates considerably over time and (2) suggest that WRRF effluent does not, when examined over the long- term, affect antibiotic resistance in Aeromonas in downstream sediment.

  15. Usefulness of Chromogenic CromoCen® AGN agar medium for the identification of the genus Aeromonas: Assessment of faecal samples.

    PubMed

    Aguilera-Arreola, M G; Portillo-Muñoz, M I; Rodríguez-Martínez, C; Castro-Escarpulli, G

    2012-08-01

    Selective screening media for the detection and identification of Aeromonas strains are needed to guide primary isolation procedures in the clinical laboratory. This study compared the selective CromoCen® AGN chromogenic agar medium for the detection and identification of Aeromonas strains that were isolated from various samples against the conventional selective agar media that are commonly used for the isolation of this organism in food, environmental and clinical samples. The Miles and Misra and ecometric methods were used to evaluate the microbiological performance of CromoCen® AGN chromogenic agar medium, which was shown to be satisfactory. A total of 14 reference Aeromonas strains, 44 wild strains and 106 clinical stool specimens were examined using both non-chromogenic selective agars that are commonly used for Aeromonas isolation and CromoCen® AGN agar. The latter exhibited 94.73% sensitivity and 100% specificity for the various samples. On CromoCen® AGN agar medium, Aeromonas formed colonies with light green, greenish and salmon pigments with or without a surrounding wide transparent zone (halo) of 2-3mm in diameter around the entire border. This medium is recommended for the isolation and potential identification of the Aeromonas genus.

  16. Dynamics of a Class 1 Integron Located on Plasmid or Chromosome in Two Aeromonas spp. Strains

    PubMed Central

    Pérez-Valdespino, Abigail; Lazarini-Martínez, Alfredo; Rivera-González, Alejandro X.; García-Hernández, Normand; Curiel-Quesada, Everardo

    2016-01-01

    Integrons are non-mobile bacterial genetic elements that carry different cassettes conferring antibiotic resistance. Cassettes can excise or integrate by action of an integron-encoded integrase, enabling bacteria to face environmental challenges. In this work, the functionality and dynamics of two integrons carrying the same cassette arrangement (dfrA12–orfF–aadA2), but located on plasmid or chromosome in two different strains were studied. In order to demonstrate the functionality of the Class 1 integrase, circular cassette integration intermediaries were PCR amplified by PCR using extrachromosomal DNA extracted from bacteria grown in the presence or absence of cassette-encoded antibiotics. Circular aadA2 and dfrA12–orfF–aadA2 cassettes were detected in cultures grown either in the presence or absence of antibiotics in both strains. No dfrA12–orfF circular intermediates could be detected under any culture conditions. These results show that both integrons are functional. However, these elements show different dynamics and functionality since the presence of streptomycin led to detectable gene rearrangements in the variable region only in the strain with the plasmid-born integron. In addition, complete integration products were demonstrated using a receptor molecule carrying an empty integron. In this case, integration products were observed in both strains even in the absence of antibiotics, but they were more evident in the strain with the plasmid-located integron when streptomycin was present in the culture medium. This suggests that integrons in the two strains respond differently to streptomycin even though DNA sequences upstream the intI1 gene, including the lexA boxes of both integrons are identical. PMID:27733851

  17. Exposure to pairs of Aeromonas strains enhances virulence in the Caenorhabditis elegans infection model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonad virulence remains poorly understood, and is difficult to predict from strain characteristics. In addition, infections are often polymicrobial (i.e., are mixed infections), and 5 -10% of such infections include two distinct aeromonads, which has an unknown impact on virulence. In this work,...

  18. An in-house multiplex pcr method to detect of putative virulence factors in aeromonas species

    PubMed Central

    Aguilera-Arreola, Ma. Guadalupe; Martínez, Alma Aidee Carmona; Castro-Escarpulli, Graciela

    2011-01-01

    A pentaplex PCR was developed and optimised to detect the genes that encode the five most important putative virulence factors in Aeromonas isolates. It seems to be more efficient than previously reported techniques and promises to be a powerful tool for more accurate risk assessments and for monitoring pathogenic strains. PMID:24031758

  19. Distribution of Aeromonas hydrophila in natural and man-made thermal effluents.

    PubMed

    Hazen, T C; Fliermans, C B

    1979-07-01

    Densities of Aeromonas hydrophila showed distinct thermal optima (25 to 35 degrees C) and thermal maxima (45 degrees C) when measured along thermal gradients created by geothermal and nuclear reactor effluents. Survival of A. hydrophila never exceeded 48 h at temperatures of greater than 45 degrees C. Thermophilic strains could not be isolated at any site.

  20. Strain Variation in Mycobacterium marinum Fish Isolates

    PubMed Central

    Ucko, M.; Colorni, A.; Kvitt, H.; Diamant, A.; Zlotkin, A.; Knibb, W. R.

    2002-01-01

    A molecular characterization of two Mycobacterium marinum genes, 16S rRNA and hsp65, was carried out with a total of 21 isolates from various species of fish from both marine and freshwater environments of Israel, Europe, and the Far East. The nucleotide sequences of both genes revealed that all M. marinum isolates from fish in Israel belonged to two different strains, one infecting marine (cultured and wild) fish and the other infecting freshwater (cultured) fish. A restriction enzyme map based on the nucleotide sequences of both genes confirmed the divergence of the Israeli marine isolates from the freshwater isolates and differentiated the Israeli isolates from the foreign isolates, with the exception of one of three Greek isolates from marine fish which was identical to the Israeli marine isolates. The second isolate from Greece exhibited a single base alteration in the 16S rRNA sequence, whereas the third isolate was most likely a new Mycobacterium species. Isolates from Denmark and Thailand shared high sequence homology to complete identity with reference strain ATCC 927. Combined analysis of the two gene sequences increased the detection of intraspecific variations and was thus of importance in studying the taxonomy and epidemiology of this aquatic pathogen. Whether the Israeli M. marinum strain infecting marine fish is endemic to the Red Sea and found extremely susceptible hosts in the exotic species imported for aquaculture or rather was accidentally introduced with occasional imports of fingerlings from the Mediterranean Sea could not be determined. PMID:12406715

  1. POTENTIAL FOR GREAT EGRETS (ARDEA ALBA) TO TRANSMIT A VIRULENT STRAIN OF AEROMONAS HYDROPHILA AMONG CHANNEL CATFISH (ICTALURUS PUNCTATUS) CULTURE PONDS.

    PubMed

    Jubirt, Madison M; Hanson, Larry A; Hanson-Dorr, Katie C; Ford, Lorelei; Lemmons, Scott; Fioranelli, Paul; Cunningham, Fred L

    2015-07-01

    Aeromonas hydrophila is a gram-negative, rod-shaped, facultative, anaerobic bacterium that is ubiquitous in freshwater and slightly brackish aquatic environments and infects fish, humans, reptiles, and birds. Recent severe outbreaks of disease in commercial channel catfish (Ictalurus punctatus) aquaculture ponds have been associated with a highly virulent A. hydrophila strain (VAH), which is genetically distinct from less-virulent strains. The epidemiology of this disease has not been determined. Given that A. hydrophila infects birds, we hypothesized that fish-eating birds may serve as a reservoir for VAH and spread the pathogen by flying to uninfected ponds. Great Egrets (Ardea alba) were used in this transmission model because these wading birds frequently prey on farmed catfish. Great Egrets that were fed VAH-infected catfish shed VAH in feces demonstrating their potential to spread VAH.

  2. POTENTIAL FOR GREAT EGRETS (ARDEA ALBA) TO TRANSMIT A VIRULENT STRAIN OF AEROMONAS HYDROPHILA AMONG CHANNEL CATFISH (ICTALURUS PUNCTATUS) CULTURE PONDS.

    PubMed

    Jubirt, Madison M; Hanson, Larry A; Hanson-Dorr, Katie C; Ford, Lorelei; Lemmons, Scott; Fioranelli, Paul; Cunningham, Fred L

    2015-07-01

    Aeromonas hydrophila is a gram-negative, rod-shaped, facultative, anaerobic bacterium that is ubiquitous in freshwater and slightly brackish aquatic environments and infects fish, humans, reptiles, and birds. Recent severe outbreaks of disease in commercial channel catfish (Ictalurus punctatus) aquaculture ponds have been associated with a highly virulent A. hydrophila strain (VAH), which is genetically distinct from less-virulent strains. The epidemiology of this disease has not been determined. Given that A. hydrophila infects birds, we hypothesized that fish-eating birds may serve as a reservoir for VAH and spread the pathogen by flying to uninfected ponds. Great Egrets (Ardea alba) were used in this transmission model because these wading birds frequently prey on farmed catfish. Great Egrets that were fed VAH-infected catfish shed VAH in feces demonstrating their potential to spread VAH. PMID:25984772

  3. Incidence of Aeromonas spp. infection in fish and chicken meat and its related public health hazards: A review

    PubMed Central

    Praveen, Praveen Kumar; Debnath, Chanchal; Shekhar, Shashank; Dalai, Nirupama; Ganguly, Subha

    2016-01-01

    Aeromonas is recognized to cause a variety of diseases in man. In humans, they are associated with intestinal and extra-intestinal infections. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors such as enterotoxins, hemolysins or cytotoxins, and antibiotic resistance against different antibiotics. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. Comprehensive enteric disease surveillance strategies, prevention and education are essential for meeting the challenges in the years ahead. It is important for us to promote the value of enteric cultures when patients have a gastrointestinal illness or bloody diarrhea or when multiple cases of enteric disease occur after a common exposure. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors, such as enterotoxins, hemolysins or cytotoxins. It has been established that aerolysin is a virulence factor contributing to the pathogenesis of Aeromonas hydrophila infection. Fish and chicken play an important role in the transmission of this pathogen to humans. In the present study, the high prevalence of toxin-producing strains was found among the Aeromonas isolates. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. The present review was constructed with a view to highlight the zoonotic importance of Aeromonas pathogen in fish and chicken meat. PMID:27051177

  4. Adherence to HEp-2 cells and enteropathogenic potential of Aeromonas spp.

    PubMed

    Grey, P A; Kirov, S M

    1993-04-01

    Aeromonas strains (total = 60) of clinical, water and food origin were tested for adherence to HEp-2 cells. Environmental strains were selected (except for A. caviae) to include primarily those expressing other virulence-associated properties. Adhesion was markedly species-dependent (A. veronii biotype sobria, 15 of 26 [58%]. A caviae, 4 of 12 [33%] and A. hydrophila, 2 of 8 [11%]). A. veronii biotype sobria were adhesive, irrespective of source (62 and 54% for clinical and environmental strains, respectively). Adherent strains of this species were enterotoxin-positive and most (13 of 15) grew at 43 degrees C. A. caviae isolated from clinical specimens contained a higher proportion (75%) of adherent strains than environmental strains (13%). Virulent subsets of A. veronii biotype sobria and A. caviae are adherent to HEp-2 cells. The HEp-2 assay is a useful model for investigating mechanisms of adherence and enteropathogenicity of virulent Aeromonas species.

  5. Analysis of the interaction of Aeromonas caviae, A. hydrophila and A. sobria with mucins.

    PubMed

    Ascencio, F; Martinez-Arias, W; Romero, M J; Wadström, T

    1998-03-01

    Aeromonas species are known to be involved in human gastrointestinal diseases. These organisms colonize the gastrointestinal tract. Aeromonas hydrophila, A. caviae, and A. sobria have been demonstrated microscopically to adhere to animal cell lines that express mucous receptors, but quantitative studies of adherence to mucosal components such as mucin have not been published to date. Purified bovine submaxillary gland, hog gastric mucin, and fish skin mucin were used as a model to study mucin-binding activity among A. caviae, A. hydrophila, and A. sobria strains. Our findings revealed that binding of radiolabeled and enzyme-conjugated mucins to Aeromonas cells varied depending on the labeling procedure. The highest binding was observed when the three mucin preparations were labeled with horseradish peroxidase. Binding of the various horseradish peroxidase-labeled mucins by A. caviae, A. hydrophila, and A. sobria cells is a common property among Aeromonas species isolated from human infections, diseased fish, and from environmental sources. The proportion of Aeromonas strains which bind the various horseradish peroxidase-labeled mucins was significantly higher for A. hydrophila than for A. caviae and A. sobria. Bacterial cell-surface extracts containing active mucin-binding components recognized the horseradish peroxidase-labeled mucins. The molecular masses of the mucin-binding proteins were estimated by SDS-PAGE and Western blot as follows: A. caviae strain A4812 (95 and 44 kDa); A. hydrophila strain 48748 (97, 45, 33 and 22 kDa); and A. sobria strain 48739 (95 and 43 kDa). Mucin interaction with Aeromonas cells was also studied in terms of growth in mucin-rich media. The culture conditions greatly influence the expression of A. hydrophila mucin-binding activity.

  6. DISTRIBUTION OF SIX VIRULENCE FACTORS IN AEROMONAS SPECIES ISOLATED FROM US DRINKING WATER UTILITIES: A PCR IDENTIFICATION

    EPA Science Inventory

    Surveys of finished drinking water conducted by the U.S. EPA during 2000-2001, revealed 7 out of 16 water utilities encompassing four states, were contaminated with Aeromonas species. A Polymerase Chain reaction (PCR) based genetic characterization determined the presence of six...

  7. First Occurrence of an IMP Metallo-β-Lactamase in Aeromonas caviae: IMP-19 in an Isolate from France▿

    PubMed Central

    Neuwirth, Catherine; Siebor, Eliane; Robin, Frederic; Bonnet, Richard

    2007-01-01

    We describe the first IMP metallo-β-lactamase in Aeromonas caviae: IMP-19, which differed from IMP-2 by a single amino acid change (Arg to Ala at position 38). blaIMP-19 was found within a class 1 integron located on a 35-kb plasmid. This is also the first description of an IMP producer in France. PMID:17938180

  8. Infection and disease progress of motile Aeromonas septicemia caused by virulent Aeromonas hydrophila in channel catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Motile Aeromonas septicemia (MAS), caused by virulent clonal isolates of Aeromonas hydrophila (vAh), is emerging as a major disease in channel catfish (Ictalurus punctatus) aquaculture in the Southeastern United States. Predisposing conditions leading to vAh infection in catfish were however largely...

  9. Resistance and Inactivation Kinetics of Bacterial Strains Isolated from the Non-Chlorinated and Chlorinated Effluents of a WWTP

    PubMed Central

    Martínez-Hernández, Sylvia; Vázquez-Rodríguez, Gabriela A.; Beltrán-Hernández, Rosa I.; Prieto-García, Francisco; Miranda-López, José M.; Franco-Abuín, Carlos M.; Álvarez-Hernández, Alejandro; Iturbe, Ulises; Coronel-Olivares, Claudia

    2013-01-01

    The microbiological quality of water from a wastewater treatment plant that uses sodium hypochlorite as a disinfectant was assessed. Mesophilic aerobic bacteria were not removed efficiently. This fact allowed for the isolation of several bacterial strains from the effluents. Molecular identification indicated that the strains were related to Aeromonas hydrophila, Escherichia coli (three strains), Enterobacter cloacae, Kluyvera cryocrescens (three strains), Kluyvera intermedia, Citrobacter freundii (two strains), Bacillus sp. and Enterobacter sp. The first five strains, which were isolated from the non-chlorinated effluent, were used to test resistance to chlorine disinfection using three sets of variables: disinfectant concentration (8, 20 and 30 mg·L−1), contact time (0, 15 and 30 min) and water temperature (20, 25 and 30 °C). The results demonstrated that the strains have independent responses to experimental conditions and that the most efficient treatment was an 8 mg·L−1 dose of disinfectant at a temperature of 20 °C for 30 min. The other eight strains, which were isolated from the chlorinated effluent, were used to analyze inactivation kinetics using the disinfectant at a dose of 15 mg·L−1 with various retention times (0, 10, 20, 30, 60 and 90 min). The results indicated that during the inactivation process, there was no relationship between removal percentage and retention time and that the strains have no common response to the treatments. PMID:23924881

  10. [Resistance to antimicrobial agents, hemolytic activity and plasmids in Aeromonas species].

    PubMed

    Morita, K; Watanabe, N; Kanamori, M

    1990-06-01

    A total of 174 Aeromonas isolates consisting of 100 strains from patients with diarrhea being mainly overseas travellers nd healthy subjects, and 74 strains from environmental sources including foods, fish, fresh water, sea water and river soil collected in the area of Tokyo Metropolis and Kanagawa Prefecture was examined for the antimicrobial resistance, presence of plasmids and hemolytic activity. Almost all the isolates (99.4%) were resistant to aminobenzyl penicillin. The isolation frequency of chloramphenicol- or tetracycline-resistant strain was low. Most environmental isolates of A. hydrophila were resistant to multiple antimicrobial agents. Thirty-seven percent of environmental isolates and 39% of human fecal ones carried plasmids. In environmental isolates, seven A. hydrophila and three A. sobria strains carried 63- to 150-kilobase pair (kb) conjugative R plasmids. Two A. hydrophila strains from both the healthy subject and domestic case with diarrhea carried 58- to 90-kb conjugative R plasmids, respectively. None of the isolates from the feces of overseas traveller's diarrhea carried the plasmid. Irrespective of the sources. A. hydrophila showed the highest hemolytic activity among three Aeromonas species. Eighty percent or more of A. hydrophila isolates were of hemolysin positive. The hemolytic titer of A. hydrophila strains from human feces was higher than that of the strains from environmental sources. PMID:2401817

  11. Aeromonas spp. induce apoptosis of epithelial cells through an oxidant-dependent activation of the mitochondrial pathway.

    PubMed

    Krzyminska, Sylwia; Tanska, Anna; Kaznowski, Adam

    2011-07-01

    We investigated interactions of Aeromonas caviae, Aeromonas veronii biotype sobria and Aeromonas hydrophila strains, isolated from faecal specimens of humans with gastroenteritis, with HT29 intestinal epithelial cells. All strains were found to be cytotoxic to the cells. Bacterial infection caused generation of reactive oxygen species (ROS) and nitric oxide radical (NO(·)). The maximal levels of ROS and NO(·) were 14 and 35 times, respectively, greater in cells infected with Aeromonas spp. than in those incubated with non-pathogenic Escherichia coli. The cells incubated with cytolytic enterotoxin isolated from A. veronii biotype sobria induced the highest level of ROS and caused the highest cytotoxicity. We observed that increased accumulation of intracellular ROS leads to a loss of mitochondrial membrane potential (ΔΨ(m)). Analyses of cellular morphology and DNA fragmentation revealed characteristic features of cells undergoing apoptosis. The process was dependent on the activation of caspases, and was completely blocked by the pan-caspase inhibitor z-VAD-fmk. Treatment of infected HT29 cells with three distinct antioxidants prevented intracellular ROS production, mitochondrial damage and apoptosis. The Pearson linear test revealed positive correlations between apoptotic index at 24 h and percentage cytotoxicity, ROS production, NO(·) production and loss of ΔΨ(m). This study has provided new insights into the mechanisms contributing to the development of Aeromonas-associated gastroenteritis. The results indicate that bacteria-induced apoptosis of epithelial cells results from mitochondrial depolarization due to oxidative stress.

  12. Diversity and antibiotic resistance of Aeromonas spp. in drinking and waste water treatment plants.

    PubMed

    Figueira, Vânia; Vaz-Moreira, Ivone; Silva, Márcia; Manaia, Célia M

    2011-11-01

    The taxonomic diversity and antibiotic resistance phenotypes of aeromonads were examined in samples from drinking and waste water treatment plants (surface, ground and disinfected water in a drinking water treatment plant, and raw and treated waste water) and tap water. Bacteria identification and intra-species variation were determined based on the analysis of the 16S rRNA, gyrB and cpn60 gene sequences. Resistance phenotypes were determined using the disc diffusion method. Aeromonas veronii prevailed in raw surface water, Aeromonas hydrophyla in ozonated water, and Aeromonas media and Aeromonas puntacta in waste water. No aeromonads were detected in ground water, after the chlorination tank or in tap water. Resistance to ceftazidime or meropenem was detected in isolates from the drinking water treatment plant and waste water isolates were intrinsically resistant to nalidixic acid. Most of the times, quinolone resistance was associated with the gyrA mutation in serine 83. The gene qnrS, but not the genes qnrA, B, C, D or qepA, was detected in both surface and waste water isolates. The gene aac(6')-ib-cr was detected in different waste water strains isolated in the presence of ciprofloxacin. Both quinolone resistance genes were detected only in the species A. media. This is the first study tracking antimicrobial resistance in aeromonads in drinking, tap and waste water and the importance of these bacteria as vectors of resistance in aquatic environments is discussed.

  13. Multidrug-resistant (MDR) Aeromonas recovered from the metropolitan area of Valencia (Spain): diseases spectrum and prevalence in the environment.

    PubMed

    Esteve, C; Alcaide, E; Giménez, M J

    2015-01-01

    Aeromonas infections are rare in Europe and often related to traveller's diarrhoea. A total of 185 Aeromonas isolates from river water, fish and clinical sources, recovered during a 1-year period, were used to investigate the disease spectrum and impact of multidrug-resistant (MDR) strains. They were all identified by biochemical tests and 25% of them were also identified by sequencing of the 16S rRNA gene. The minimum inhibitory concentrations (MICs) of 21 antimicrobials were determined for all isolates by broth microdilution/E-strips methods, and susceptibility was assessed according to the Clinical and Laboratory Standards Institute (CLSI). Strains pathogenicity was determined by using Swiss Webster mice as the animal model. Aeromonas diseases had an incidence of around 20 cases/million inhabitants in the metropolitan area of Valencia (Spain). Acute gastroenteritis in children with no history of travel abroad was the main pathology. These cases were related to A. caviae, A. veronii biovar sobria, A. hydrophila and A. dhakensis. A significant incidence of A. caviae in humans was found, while the other species were equally present in clinical and environmental origins. A. jandaei, A. bestiarum and A. media had mainly an environmental distribution. The prevalence of MDR Aeromonas was maximal in clinical samples, and resistance phenotypes were significantly related to this source. 7.2% of environmental Aeromonas was resistant to at least five drugs; most of them were moderately virulent for mice and, in addition, belonged to clinically significant species. The present study demonstrates a diseases spectrum similar to that reported in tropical countries, and also that pathogenic and heavily MDR Aeromonas are present in environmental reservoirs. MDR Aeromonas from any source analysed were susceptible to aztreonam, netilmicin, cefotaxime, ceftazidime, cefepime and fluoroquinolones.

  14. [Aeromonas hydrophila in the drinking water in Djibouti: commensal germ or diarrhea-causing agent?].

    PubMed

    Fox, E; Mikhail, I A; Haberberger, R L; Abbatte, E A; Ahmed, M H

    1990-04-01

    To investigate the bacteriological quality of drinking water used by inhabitants of the Republic of Djibouti who were not supplied with piped running water, we analysed 16 fresh-water samples from various sources. Only 3 samples were sterile; they were taken from village pumps and from a water-truck. Eleven samples yielded colonies of Aeromonas hydrophila too numerous to be counted; they were taken from water tanks, metal barrels, or wells dug in either dry river beds or along the seashore. We speculate that this high isolation frequency of Aeromonas hydrophila in fresh water samples may be related to conditions that are exceptionally favourable for the growth of the bacterium (e.g. high temperature and elevated concentrations of certain salts and minerals in the fresh water of Djibouti). We wonder nevertheless whether the infected water supplies were a source of diarrhoea for humans. Indeed, antibiotic resistance patterns were dissimilar when the 11 environmental strains were compared to 7 strains of Aeromonas hydrophila isolated from diarrhoeal patients in Djibouti during the same period. More studies are needed to determine if Aeromonas hydrophila is always a commensal inhabitant of fresh water in Djibouti, or if it can be a cause of infectious diarrhoea. Accordingly, Public Health authorities in Djibouti will be able to decide if water from wells and tanks is safe for drinking, or if it needs disinfection before consumption.

  15. Genome sequencing and annotation of Aeromonas sp. HZM

    PubMed Central

    Chua, Patric; Har, Zi Mei; Austin, Christopher M.; Yule, Catherine M.; Dykes, Gary A.; Lee, Sui Mae

    2015-01-01

    We report the draft genome sequence of Aeromonas sp. strain HZM, isolated from tropical peat swamp forest soil. The draft genome size is 4,451,364 bp with a G + C content of 61.7% and contains 10 rRNA sequences (eight copies of 5S rRNA genes, single copy of 16S and 23S rRNA each). The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. JEMQ00000000. PMID:26484220

  16. Aeromonas-associated infections in developing countries.

    PubMed

    Ghenghesh, Khalifa Sifaw; Ahmed, Salwa F; El-Khalek, Rania Abdel; Al-Gendy, Atef; Klena, John

    2008-01-01

    Although their role in gastroenteritis is controversial, Aeromonas species are recognized as etiological agents of a wide spectrum of diseases in man and animals. In developing countries, potentially pathogenic Aeromonas sp. are very common in drinking water and in different types of foods, particularly seafood. Several food-borne and water-borne outbreaks as well nosocomial outbreaks associated with aeromonads have been reported. Significant association of Aeromonas sp. with diarrhoea in children has been reported from several countries. These organisms are important causes of skin and soft-tissue infections and aspiration pneumonia following contact with water and after floods. High incidence of antimicrobial resistance, including to third-generation cephalosporins and the fluoroquinolones, is found among Aeromonas sp. isolated from clinical sources in some developing countries in Asia. Isolating and identifying Aeromonas sp. to genus level is simple and requires resources that are available in most microbiology laboratories for processing common enteric bacteria. The present review will cover the epidemiology, clinical syndromes, low-cost diagnostic methods, and antimicrobial resistance and treatment of Aeromonas infections in developing countries.

  17. Diversity of antibiotic-resistance genes in Canadian isolates of Aeromonas salmonicida subsp. salmonicida: dominance of pSN254b and discovery of pAsa8

    PubMed Central

    Trudel, Mélanie V.; Vincent, Antony T.; Attéré, Sabrina A.; Labbé, Myriam; Derome, Nicolas; Culley, Alexander I.; Charette, Steve J.

    2016-01-01

    The bacterium Aeromonas salmonicida subsp. salmonicida is a common pathogen in fish farms worldwide. Since the antibiotic resistance of this bacterial species is on the increase, it is important to have a broader view on this issue. In the present study, we tested the presence of known plasmids conferring multi-drug resistance as well as antibiotic resistance genes by a PCR approach in 100 Canadian A. salmonicida subsp. salmonicida isolates. Our study highlighted the dominance of the conjugative pSN254b plasmid, which confers multi-drug resistance. We also identified a new multi-drug plasmid named pAsa8, which has been characterized by a combination of sequencing technologies (Illumina and Oxford nanopore). This new plasmid harbors a complex class 1 integron similar to the one of the Salmonella genomic island 1 (SGI1) found in Salmonella enterica and Proteus mirabilis. Consequently, in addition to providing an update on the A. salmonicida subsp. salmonicida isolates that are resistant to antibiotics, our data suggest that this bacterium is potentially an important reservoir of drug resistance genes and should consequently be monitored more extensively. In addition, we describe a screening method that has the potential to become a diagnostic tool that is complementary to other methods currently in use. PMID:27752114

  18. Two novel temperate bacteriophages co-existing in Aeromonas sp. ARM81 - characterization of their genomes, proteomes and DNA methyltransferases.

    PubMed

    Dziewit, Lukasz; Radlinska, Monika

    2016-08-01

    Aeromonas species are causative agents of a wide spectrum of diseases in animals and humans. Although these bacteria are commonly found in various environments, little is known about their phages. Thus far, only one temperate Aeromonas phage has been characterized. Whole-genome sequencing of an Aeromonas sp. strain ARM81 revealed the presence of two prophage clusters. One of them is integrated into the chromosome and the other was maintained as an extrachromosomal, linear plasmid-like prophage encoding a protelomerase. Both prophages were artificially and spontaneously inducible. We separately isolated both phages and compared their genomes with other known viruses. The novel phages show no similarity to the previously characterized Aeromonas phages and might represent new evolutionary lineages of viruses infecting Aeromonadaceae. Apart from the comparative genomic analyses of these phages, complemented with their structural and molecular characterization, a functional analysis of four DNA methyltransferases encoded by these viruses was conducted. One of the investigated N6-adenine-modifying enzymes shares sequence specificity with a Dam-like methyltransferase of its bacterial host, while another one is non-specific, as it catalyzes adenine methylation in various sequence contexts. The presented results shed new light on the diversity of Aeromonas temperate phages.

  19. Effect of acute and chronic arsenic exposure on growth, structure and virulence of Aeromonas hydrophila isolated from fish.

    PubMed

    Goswami, Ramansu; Ghosh, Debabrata; Saha, Dhira Rani; Padhy, Pratap Kumar; Mazumder, Shibnath

    2011-02-01

    Aeromonas hydrophila being a ubiquitous bacterium is prone to arsenic exposure. The present study was designed to determine the role of arsenic on growth and virulence of A. hydrophila. Exposure to arsenic (1 mg L(-1) and 2 mg L(-1)) had no effect on growth but significantly inhibited the hemolytic and cytotoxic potential of exposed bacteria. Transmission electron microscopy revealed loss of membrane integrity and presence of condensed cytoplasm suggestive of acute stress in bacteria exposed to arsenic. Arsenic-adapted bacteria were developed by repeated sub-culturing in presence of arsenic. Arsenic-adaptation led to significant recovery in hemolytic and cytotoxic potential. The arsenic-adapted bacteria exhibited normal membrane integrity, decreased cytoplasmic condensation and possessed scattered polysome like structures in the cytoplasm. A positive correlation was observed between arsenic tolerance and resistance to several antimicrobials. Arsenic-adaptation failed to confer cross-protection to mercury and cadmium stress. SDS-PAGE analysis revealed the expression of two new proteins of approximately 85 kDa and 79 kDa respectively in arsenic-adapted A. hydrophila. Plasmid-curing and transformation studies clearly indicate plasmid has no role on arsenic resistance trait of the bacteria. Our study, for the first time, reports a structure and function relationship of xenobiotics on bacteria.

  20. Biliary tract infections caused by Aeromonas species.

    PubMed

    Chao, C M; Lai, C C; Tang, H J; Ko, W C; Hsueh, P-R

    2013-02-01

    This study investigated the clinical and microbiological characteristics of patients with Aeromonas infections of the biliary tract. Patients with bile cultures positive for Aeromonas species during the period July 2004 to December 2011 were identified from a computerized database of a hospital in Taiwan. Patients with Aeromonas infections of the biliary tract were further identified. During the study period, a total of 1,142 isolates of Aeromonas species were obtained from 750 patients. Of those patients, 91 (12.1 %) had Aeromonas infections of the biliary tract. The annual incidence (episodes per 10,000 patient-days) of biliary tract infections caused by all Aeromonas species was 0.31 in 2007, 0.12 in 2010, and 0.27 in 2011. A. hydrophila was the most common species isolated (n = 41, 45.1 %), followed by A. caviae (n = 30, 33.0 %), A. veronii biovar sobria (n = 15, 16.5 %), and A. veronii biovar veronii (n = 5, 5.5 %). The majority of patients (n = 77, 84.6 %) had polymicrobial infections. Hepatobiliary stones (n = 50, 54.9 %) and hepatobiliary cancer (n = 38, 41.8 %) were the most common underlying diseases, followed by diabetes mellitus (n = 29, 31.9 %) and liver cirrhosis (n = 7, 7.7 %). The in-hospital mortality rate was 8.8 %. Infection-related mortality was associated with underlying immunocompromised condition (p = 0.044) and use of mechanical ventilation (p = 0.004), but was not associated with inappropriate antibiotic usage or concomitant bacteremia (n = 8, 8.8 %). In conclusion, biliary tract infections caused by Aeromonas species are not uncommon and can develop in both immunocompromised and immunocompetent patients; however, patients with underlying hepatobiliary diseases are particularly susceptible to these infections.

  1. Functional Genomics of the Aeromonas salmonicida Lipopolysaccharide O-Antigen and A-Layer from Typical and Atypical Strains

    PubMed Central

    Merino, Susana; de Mendoza, Elena; Canals, Rocío; Tomás, Juan M.

    2015-01-01

    The A. salmonicida A450 LPS O-antigen, encoded by the wbsalmo gene cluster, is exported through an ABC-2 transporter-dependent pathway. It represents the first example of an O-antigen LPS polysaccharide with three different monosaccharides in their repeating unit assembled by this pathway. Until now, only repeating units with one or two different monosaccharides have been described. Functional genomic analysis of this wbsalmo region is mostly in agreement with the LPS O-antigen structure of acetylated l-rhamnose (Rha), d-glucose (Glc), and 2-amino-2-deoxy-d-mannose (ManN). Between genes of the wbsalmo we found the genes responsible for the biosynthesis and assembly of the S-layer (named A-layer in these strains). Through comparative genomic analysis and in-frame deletions of some of the genes, we concluded that all the A. salmonicida typical and atypical strains, other than A. salmonicida subsp. pectinolytica strains, shared the same wbsalmo and presence of A-layer. A. salmonicida subsp. pectinolytica strains lack wbsalmo and A-layer, two major virulence factors, and this could be the reason they are the only ones not found as fish pathogens. PMID:26082990

  2. Lippia alba essential oil promotes survival of silver catfish (Rhamdia quelen) infected with Aeromonas sp.

    PubMed

    Sutili, Fernando J; Cunha, Mauro A; Ziech, Rosangela E; Krewer, Carina C; Zeppenfeld, Carla C; Heldwein, Clarissa G; Gressler, Leticia T; Heinzmann, Berta M; Vargas, Agueda C; Baldisserotto, Bernardo

    2015-03-01

    In vitro and in vivo activity of the Lippia alba essential oil (EO) against Aeromonas sp. was evaluated. In the in vitro assay the minimum inhibitory concentration (MIC) and a minimum bactericidal concentration (MBC) of EO for Aeromonas cells were determined using the microdilution method. Twenty five strains of Aeromonas sp. isolated from infected fish obtained from local fish farms were used. MIC and MBC values were 2862 and 5998 µg mL-1 for L. alba EO and 0.5 and 1.2 µg mL-1 for gentamicin, respectively. In the in vivo assay silver catfish juveniles (Rhamdia quelen) (7.50 ± 1.85 g and 10.0 ± 1.0 cm) with typical injuries associated to Aeromonas infection were divided into four treatments (in triplicate n=10): untreated fish (negative control), 10 mg L-1 of gentamicin, and 20 or 50 µL L-1 of EO. Fish were maintained in aerated 20 L plastic boxes. After 10 days survival of silver catfish infected with Aermonas sp. and treated with essential oil (50 µL L-1) was greater than 90%. PMID:25789790

  3. Population dynamics and antimicrobial susceptibility of Aeromonas spp. along a salinity gradient in an urban estuary in Northeastern Brazil.

    PubMed

    Silva, Camila Magalhães; Evangelista-Barreto, Norma Suely; Vieira, Regine Helena Silva Dos Fernandes; Mendonça, Kamila Vieira; de Sousa, Oscarina Viana

    2014-12-15

    The main objective of this study was to quantify population and identify culturable species of Aeromonas in sediment and surface water collected along a salinity gradient in an urban estuary in Northeastern Brazil. Thirty sediment samples and 30 water samples were collected from 3 sampling locations (A, B and C) between October 2007 and April 2008. The Aeromonas count was 10-7050CFU/mL (A), 25-38,500CFU/mL (B) and<10CFU/mL (C) for water samples, and ∼100-37,500CFU/g (A), 1200-43,500CFU/g (B) and<10CFU/g (C) for sediment samples. Five species (Aeromonas caviae, A. sobria, A. trota, A. salmonicida and A. allosaccharophila) were identified among 41 isolates. All strains were sensitive to chloramphenicol and ceftriaxone, whereas 33 (80, 4%) strains were resistant to at least 2 of the 9 antibiotics tested. Resistance to erythromycin was mostly plasmidial. In conclusion, due to pollution, the Cocó River is contaminated by pathogenic strains of Aeromonas spp. with a high incidence of antibacterial resistance, posing a serious risk to human health.

  4. COMPARISON OF STRAINS OF SPOROTRICHUM SCHENCKII ISOLATED FROM NATURE1

    PubMed Central

    Howard, Dexter H.; Orr, G. F.

    1963-01-01

    Howard, Dexter H. (University of California, Los Angeles) and G. F. Orr. Comparison of strains of Sporotrichum schenckii isolated from nature. J. Bacteriol. 85:816–821. 1963.—Several strains of fungi, tentatively considered to be members of the genus Sporotrichum, have been isolated from soil and from other sources in nature. The striking morphological similarity of these isolates to strains of S. schenckii led to a comparative study of their biological properties. Nine strains of Sporotrichum from nature were compared with twelve strains of S. schenckii isolated from cases of clinical sporotrichosis. The nine saprophytic isolates were indistinguishable microscopically and macroscopically from strains of pathogenic S. schenckii when cultures were prepared on a variety of media incubated at 28 C. Only two of the nine saprophytic isolates were able to grow at 37 C. These two strains partially converted, at this temperature, to a yeast-cell phase of growth. The blastospores comprising this phase of growth were similar to those produced by S. schenckii under the same circumstances. Six of the nine saprophytes were essentially avirulent for mice. The remaining three strains had a very limited capacity to produce disease in experimental animals. The isolates are currently regarded as variants of S. schenckii. PMID:14044948

  5. Genome Sequence of Aeromonas hydrophila ATCC 7966T: Jack of All Trades▿

    PubMed Central

    Seshadri, Rekha; Joseph, Sam W.; Chopra, Ashok K.; Sha, Jian; Shaw, Jonathan; Graf, Joerg; Haft, Daniel; Wu, Martin; Ren, Qinghu; Rosovitz, M. J.; Madupu, Ramana; Tallon, Luke; Kim, Mary; Jin, Shaohua; Vuong, Hue; Stine, O. Colin; Ali, Afsar; Horneman, Amy J.; Heidelberg, John F.

    2006-01-01

    The complete genome of Aeromonas hydrophila ATCC 7966T was sequenced. Aeromonas, a ubiquitous waterborne bacterium, has been placed by the Environmental Protection Agency on the Contaminant Candidate List because of its potential to cause human disease. The 4.7-Mb genome of this emerging pathogen shows a physiologically adroit organism with broad metabolic capabilities and considerable virulence potential. A large array of virulence genes, including some identified in clinical isolates of Aeromonas spp. or Vibrio spp., may confer upon this organism the ability to infect a wide range of hosts. However, two recognized virulence markers, a type III secretion system and a lateral flagellum, that are reported in other A. hydrophila strains are not identified in the sequenced isolate, ATCC 7966T. Given the ubiquity and free-living lifestyle of this organism, there is relatively little evidence of fluidity in terms of mobile elements in the genome of this particular strain. Notable aspects of the metabolic repertoire of A. hydrophila include dissimilatory sulfate reduction and resistance mechanisms (such as thiopurine reductase, arsenate reductase, and phosphonate degradation enzymes) against toxic compounds encountered in polluted waters. These enzymes may have bioremediative as well as industrial potential. Thus, the A. hydrophila genome sequence provides valuable insights into its ability to flourish in both aquatic and host environments. PMID:16980456

  6. Edwardsiella tarda and Aeromonas hydrophila isolated from diseased Southern flounder (Paralichthys lethostigma) are virulent to channel catfish and Nile tilapia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study is to identify bacterial pathogens isolated from diseased Southern flounder and determine their virulence to channel catfish and Nile tilapia. Twenty five Gram-negative bacteria isolates were recovered from five tissues (skin lesions, brain, liver, intestine, and posterior kidn...

  7. Molecular Characterization of First Human Bartonella Strain Isolated in Italy

    PubMed Central

    Ciervo, Alessandra; Petrucca, Andrea; Ciarrocchi, Simonetta; Pinto, Antonella; Bonazzi, Lucio; Fabio, Anna; Farnetti, Enrico; Chomel, Bruno B.; Ciceroni, Lorenzo

    2001-01-01

    The aim of this study was to characterize a Bartonella strain (BA-1) isolated from a blood culture of an Italian, human immunodeficiency virus-positive patient with bacillary angiomatosis. We analyzed the isolate using molecular biology methods such as whole-cell fatty acid analysis, PCR-restriction fragment length polymorphism analysis, type-specific 16S rRNA PCRs, sequence analysis of the 16S rRNA, pulsed-field gel electrophoresis, and arbitrarily primed PCR. The BA-1 isolate turned out to be a Bartonella quintana strain, similar but not identical to B. quintana Oklahoma, which was used as a control strain. PMID:11724882

  8. Metabolic activities of Lactobacillus spp. strains isolated from kefir.

    PubMed

    Yüksekdag, Zehra Nur; Beyath, Yavuz; Aslim, Belma

    2004-06-01

    A total of 21 strains of Lactobacillus species were isolated from Turkish kefir samples, in order to select the most suitable strains according to their metabolic activities including probiotic properties. As a result of the identification tests, 21 Lactobacillus isolates were identified as L. acidophilus (4%), L. helveticus (9%), L. brevis (9%), L. bulgaricus (14%), L. plantarum (14%), L. casei (19%) and L. lactis (28%). The amount of produced lactic acid, hydrogen peroxide, proteolytic activity, and acetaldehyde productions of Lactobacillus spp. were determined. Different amounts of lactic acid were produced by strains studies; however, lactic acid levels were 1.7-11.4 mg/mL. All strains produced hydrogen peroxide. L. bulgaricus Z14L strain showed no proteolytic activity, L. casei Z6L strain produced the maximum amount (0.16 mg/mL) of proteolytic activity. Acetaldehyde concentration produced in Lactobacillus strains ranged between 0.88-3.52 microg/mL.

  9. Quorum Sensing and c-di-GMP-Dependent Alterations in Gene Transcripts and Virulence-Associated Phenotypes in a Clinical Isolate of Aeromonas hydrophila

    PubMed Central

    Kozlova, Elena V.; Khajanchi, Bijay K.; Sha, Jian; Chopra, Ashok K.

    2011-01-01

    Recently, we demonstrated that the LuxS-based quorum sensing (QS) system (AI-2) negatively regulated the virulence of a diarrheal isolate SSU of Aeromonas hydrophila, while the ahyRI-based (AI-1) N-acyl-homoserine lactone system was a positive regulator of bacterial virulence. Thus, these QS systems had opposing effects on modulating biofilm formation and bacterial motility in vitro models and in vivo virulence in a speticemic mouse model of infection. In this study, we linked these two QS systems with the bacterial second messenger cyclic diguanosine monophosphate (c-di-GMP) in the regulation of virulence in A. hydrophila SSU. To accomplish this, we examined the effect of overproducing a protein with GGDEF domain, which increases c-di-GMP levels in bacteria, on the phenotype and transcriptional profiling of genes involved in biofilm formation and bacterial motility in wild-type (WT) versus its QS null mutants. We provided evidence that c-di-GMP overproduction dramatically enhanced biofilm formation and reduced motility of the WT A. hydrophila SSU, which was equitable with that of the ΔluxS mutant. On the contrary, the ΔahyRI mutant exhibited only a marginal increase in the biofilm formation with no effect on motility when c-di-GMP was overproduced. Overall, our data indicated that c-di-GMP overproduction modulated transcriptional levels of genes involved in biofilm formation and motility phenotype in A. hydrophila SSU in a QS-dependent manner, involving both AI-1 and AI-2 systems. PMID:21256953

  10. Distribution of 13 virulence genes among clinical and environmental Aeromonas spp. in Western Australia.

    PubMed

    Aravena-Román, M; Inglis, T J J; Riley, T V; Chang, B J

    2014-11-01

    We evaluated the pathogenic potential of 98 clinical and 31 environmental Aeromonas isolates by detecting the presence of 13 virulence genes using a polymerase chain reaction (PCR)-based method. The majority (96 %) of the strains contained at least one of the virulence genes. The overall distribution was aerA/haem (77 %), alt (53 %), lafA (51 %), ast (39 %), flaA (32 %), aspA (29 %), vasH (26 %), ascV (16 %) and aexT (13 %). No amplification products were detected for the genes encoding a bundle-forming pilus (BfpA and BfpG) or a Shiga-like toxin (stx-1 and stx-2). Five or more virulence genes were detected in 42 % of environmental and 24 % of clinical isolates. Among the major species, 48 % of A. hydrophila and 42 % of A. dhakensis isolates harboured five or more virulence genes compared with 19 % in A. veronii bv. sobria and none in A. caviae isolates. Our results suggest that, in Western Australia, strains of A. dhakensis and A. hydrophila are potentially more virulent than those of A. veronii bv. sobria and A. caviae, although the pathogenic potential of Aeromonas spp. is probably strain- rather than species-dependent.

  11. Ribosomal multi-operon diversity: an original perspective on the genus Aeromonas.

    PubMed

    Roger, Frédéric; Lamy, Brigitte; Jumas-Bilak, Estelle; Kodjo, Angeli; Marchandin, Hélène

    2012-01-01

    16S rRNA gene (rrs) is considered of low taxonomic interest in the genus Aeromonas. Here, 195 Aeromonas strains belonging to populations structured by multilocus phylogeny were studied using an original approach that considered Ribosomal Multi-Operon Diversity. This approach associated pulsed-field gel electrophoresis (PFGE) to assess rrn operon number and distribution across the chromosome and PCR-temporal temperature gel electrophoresis (TTGE) to assess rrs V3 region heterogeneity. Aeromonads harbored 8 to 11 rrn operons, 10 operons being observed in more than 92% of the strains. Intraspecific variability was low or nul except for A. salmonicida and A. aquariorum suggesting that large chromosomic rearrangements might occur in these two species while being extremely rarely encountered in the evolution of other taxa. rrn operon number at 8 as well as PFGE patterns were shown valuable for taxonomic purpose allowing resolution of species complexes. PCR-TTGE revealed a high rate of strains (41.5%) displaying intragenomic rrs heterogeneity. Strains isolated from human samples more frequently displayed intragenomic heterogeneity than strains recovered from non-human and environmental specimens. Intraspecific variability ranged from 0 to 76.5% of the strains. The observation of species-specific TTGE bands, the recovery of identical V3 regions in different species and the variability of intragenomic heterogeneity (1-13 divergent nucleotides) supported the occurrence of mutations and horizontal transfer in aeromonad rrs evolution. Altogether, the presence of a high number of rrn operon, the high proportion of strains harboring divergent rrs V3 region and the previously demonstrated high level of genetic diversity argued in favor of highly adaptative capabilities of aeromonads. Outstanding features observed for A. caviae supported the ongoing process of adaptation to a specialized niche represented by the gut, previously hypothesized. 16S rRNA gene is an informative marker

  12. Ribosomal Multi-Operon Diversity: An Original Perspective on the Genus Aeromonas

    PubMed Central

    Roger, Frédéric; Lamy, Brigitte; Jumas-Bilak, Estelle; Kodjo, Angeli; F., Carmagnol; E., Chachaty; C., Alba-Sauviat; C., Auvray; D., Barraud; Z., Benseddik; A., Bertrou; F., Bessis; H., Biessy; V., Blanc; Y., Boucaud-Maitre; P., Brunet; A., Michel; B., Cancet; J., Carrere; A., Cecille; G., Chambreuil; P., Chantelat; H., Chardon; C., Charrel; H., De Montclos; J.W., Decousser; J. M., Delarbre; A., Gravet; D., Deligne; C., Denoix; J., Deregnaucourt; F., Desroys du Roure; S., Dubourdieu; Z., El Harrif; C., Eloy; A., Evers; C., Febvre; D., Fevre; S., Gabriel; M. J., Galanti; E., Garnotel; M., Gavignet; F., Geffroy; G., Grise; I., Gros; I., Hermes; J., Heurte; E., Heusse; D., Jan; E., Jaouen; S., Laluque; R., Lamarca; Laurens, E.; A., Le Coustumier; E., Lecaillon; C., Lemble; M., Leneveu; S., Leotard; M. N., Letouzey; C., Malbrunot; O., Menouni; M., Morel; C., Olive; B., Pangon; J. G., Paul; J. M., Perez; P., Pouedras; D., Pressac; R., Sanchez; Y., Scat; A., Secher; J., Semon; D., Simeon; C., Simonin; J. P., Thellier; B., Tourand; A., Vachée; C., Varache; J., Vaucel; A. C., Vautrin; A., Verhaeghe; M., Villemain; L., Villeneuve; Marchandin, Hélène

    2012-01-01

    16S rRNA gene (rrs) is considered of low taxonomic interest in the genus Aeromonas. Here, 195 Aeromonas strains belonging to populations structured by multilocus phylogeny were studied using an original approach that considered Ribosomal Multi-Operon Diversity. This approach associated pulsed-field gel electrophoresis (PFGE) to assess rrn operon number and distribution across the chromosome and PCR-temporal temperature gel electrophoresis (TTGE) to assess rrs V3 region heterogeneity. Aeromonads harbored 8 to 11 rrn operons, 10 operons being observed in more than 92% of the strains. Intraspecific variability was low or nul except for A. salmonicida and A. aquariorum suggesting that large chromosomic rearrangements might occur in these two species while being extremely rarely encountered in the evolution of other taxa. rrn operon number at 8 as well as PFGE patterns were shown valuable for taxonomic purpose allowing resolution of species complexes. PCR-TTGE revealed a high rate of strains (41.5%) displaying intragenomic rrs heterogeneity. Strains isolated from human samples more frequently displayed intragenomic heterogeneity than strains recovered from non-human and environmental specimens. Intraspecific variability ranged from 0 to 76.5% of the strains. The observation of species-specific TTGE bands, the recovery of identical V3 regions in different species and the variability of intragenomic heterogeneity (1–13 divergent nucleotides) supported the occurrence of mutations and horizontal transfer in aeromonad rrs evolution. Altogether, the presence of a high number of rrn operon, the high proportion of strains harboring divergent rrs V3 region and the previously demonstrated high level of genetic diversity argued in favor of highly adaptative capabilities of aeromonads. Outstanding features observed for A. caviae supported the ongoing process of adaptation to a specialized niche represented by the gut, previously hypothesized. 16S rRNA gene is an informative

  13. Antimicrobial susceptibility of Enterococcus strains isolated from poultry faeces.

    PubMed

    Tejedor-Junco, M T; Afonso-Rodríguez, O; Martín-Barrasa, J L; González-Martín, M

    2005-02-01

    We have investigated the resistance of Enterococcus isolated from poultry faeces to antibiotics commonly used as therapy of enterococcal infections. Identification was made by the method of Facklam and Collins. Minimal inhibitory concentrations of penicillin, ampicillin, vancomycin and teicoplanin were determined and high level aminoglycoside resistance was investigated. Genes codifying high level aminoglycoside resistance (HLAR) were determined by PCR. Fifty five Enterococcus strains were isolated (63.6% E. faecalis, 12.7% E. mundtii, 9.1% E. faecium, 7.3% E. casseliflavus, 3.7% E. durans and 3.6% E. hirae). None of the strains were resistant to VAN, TEC, P or AM. HLAR was found in 34.5% of strains for SM, 27.3% for KM and 7.3% for GM. The gene for the bifunctional enzyme was found only in one strain, that showed HLAR to GM and KM. Fourteen strains harboured the gene aph(3')-III, being 11 resistant to KM and STR, and three resistant to GM, KM and STR. The remaining six strains showed HLAR to STR, but were negative for the three genes tested by PCR. The gene ant(4'4") was not detected in any of the strains. No unexpected vancomycin resistance was detected. The resistance rates among poultry strains were lower than those found among human strains isolated from hospital patients in recent Canary studies.

  14. DIFFERENTIATION OF AEROMONAS ISOLATES OBTAINED FROM DRINKING WATER DISTRIBUTION SYSTEM USING MATRIX-ASSISTED LASER DESCRIPTION/IONIZATION-MASS SPECTROMETRY (MALDI-MS)

    EPA Science Inventory

    The genus Aeromonas is one of several medically significant genera that have gained prominence due to their evolving taxonomy and controversial role in human diseases. In this study, matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to analyze the...

  15. Further Characterization of a Type III Secretion System (T3SS) and of a New Effector Protein from a Clinical Isolate of Aeromonas Hydrophila - Part I

    EPA Science Inventory

    A type III secretion system (T3SS)-associated cytotoxin, AexT, with ADP-ribosyltransferase activity and homology to Pseudomonas aeruginosa bifuncational toxins ExoT/S, was recently identified from a fish pathogen Aeromonas salmonicida. In this study, we reported the molecular cha...

  16. THE USE OF MATRIX-ASSISTED LASER DESORPTION/IONIZATION-MASS SPECTROMETRY FOR THE IDENTIFICATION OF AEROMONAS ISOLATES OBTAINED FROM WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) has long been established as a tool by which microorganisms can be characterized and identified. EPA is investigating the potential of using this technology as a way to rapidly identify Aeromonas species fo...

  17. EVALUATING VIRULENCE OF WATERBORNE AND CLINCIAL AEROMONAS ISOLATES USING GENE EXPRESSION AND MORTALITY IN NEONATAL MICE FOLLOWED BY ASSESSING CELL CULTURE'S ABILITY TO PREDICT VIRULENCE BASED ON TRANSCRIPTIONAL RESPONSE

    EPA Science Inventory

    The virulence of multiple Aeromonas spp. were assessed using two models, a neonatal mouse assay and a mouse intestinal cell culture. Transcriptional responses to both infection models were assessed using microarrays. After artificial infection with a variety of Aeromonas spp., ...

  18. Recombinant outer membrane protein C of Aeromonas hydrophila elicits mixed immune response and generates agglutinating antibodies.

    PubMed

    Yadav, Sunita Kumari; Meena, Jitendra Kumar; Sharma, Mahima; Dixit, Aparna

    2016-08-01

    Aeromonas hydrophila is a gram-negative fish pathogenic bacterium, also responsible for causing opportunistic pathological conditions in humans. It causes a number of diseases in fish due to which the fish industry incurs huge economic losses annually. Due to problems of antibiotic resistance, and the rapidity with which the infection spreads among fishes, vaccination remains the most effective strategy to combat this infection in fish populations. Among various virulence factors associated with bacterial virulence, outer membrane proteins have been widely evaluated for their vaccine potential owing to their surface exposure and related role in pathogenicity. In the present study, we have investigated the immunogenic potential of a non-specific porin, outer membrane protein C (OmpC) whose expression is regulated by the two-component regulatory system and plays a major role in the survival of A. hydrophila under different osmolaric conditions. The full-length gene (~1 kb) encoding OmpC of A. hydrophila was cloned, characterized and expressed in E. coli. High yield (~112 mg/L at shake flask level) of the recombinant OmpC (rOmpC) (~40 kDa) of A. hydrophila was obtained upon purification from inclusion bodies using Ni(2+)-NTA affinity chromatography. Immunization with purified rOmpC in murine model generated high endpoint (>1:40,000) titers. IgG isotyping, ELISA and ELISPOT assay indicated mixed immune response with a TH2 bias. Also, the anti-rOmpC antibodies were able to agglutinate A. hydrophila in vitro and exhibited specific cross-reactivity with different Aeromonas strains, which will facilitate easy detection of different Aeromonas isolates in infected samples. Taken together, these data clearly indicate that rOmpC could serve as an effective vaccine against different strains of Aeromonas, a highly heterogenous group of bacteria. PMID:27328672

  19. Development of a rapid identification method for Aeromonas species by multiplex-PCR.

    PubMed

    Sen, Keya

    2005-11-01

    Existing biochemical methods cannot distinguish among some species of Aeromonads, while genetic methods are labor intensive. In this study, primers were developed to three genes of Aeromonas: lipase, elastase, and DNA gyraseB. In addition, six previously described primer sets, five corresponding to species-specific signature regions of the 16S rRNA gene from A. veronii, A. popoffii, A. caviae, A. jandaei, and A. schubertii, respectively, and one corresponding to A. hydrophila specific lipase (hydrolipase), were chosen. The primer sets were combined in a series of multiplex-PCR (mPCR) assays against 38 previously characterized strains. Following PCR, each species was distinguished by the production of a unique combination of amplicons. When the assays were tested using 63 drinking water isolates, there was complete agreement in the species identification (ID) for 59 isolates, with ID established by biochemical assays. Sequencing the gyrB and the 16S rRNA gene from the remaining four strains established that the ID obtained by mPCR was correct for three strains. For only one strain, no consensus ID could be obtained. A rapid and reliable method for identification of different Aeromonas species is proposed that does not require restriction enzyme digestions, thus simplifying and speeding up the process.

  20. Aeromonas dhakensis, an Increasingly Recognized Human Pathogen.

    PubMed

    Chen, Po-Lin; Lamy, Brigitte; Ko, Wen-Chien

    2016-01-01

    Aeromonas dhakensis was first isolated from children with diarrhea in Dhaka, Bangladesh and described in 2002. In the past decade, increasing evidence indicate this species is widely distributed in the environment and can cause a variety of infections both in human and animals, especially in coastal areas. A. dhakensis is often misidentified as A. hydrophila, A. veronii, or A. caviae by commercial phenotypic tests in the clinical laboratory. Correct identification relies on molecular methods. Increasingly used matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) may be able to identify Aeromonas specie rapidly and accurately. A. dhakensis has shown its potent virulence in different animal models and clinical infections. Although several virulence factors had been reported, no single mechanism is conclusive. Characteristically A. dhakensis is the principal species causing soft tissue infection and bacteremia, especially among patients with liver cirrhosis or malignancy. Of note, A. dhakensis bacteremia is more lethal than bacteremia due to other Aeromonas species. The role of this species in gastroenteritis remains controversial. Third generation cephalosporins and carbapenems should be used cautiously in the treatment of severe A. dhakensis infection due to the presence of AmpC ββ-lactamase and metallo-β-lactamase genes, and optimal regimens may be cefepime or fluoroquinolones. Studies of bacterial virulence factors and associated host responses may provide the chance to understand the heterogeneous virulence between species. The hypothesis A. dhakensis with varied geographic prevalence and enhanced virulence that compared to other Aeromonas species warrants more investigations.

  1. An Asian Origin of Virulent Aeromonas hydrophila Responsible for Disease Epidemics in United States-Farmed Catfish

    PubMed Central

    Hossain, Mohammad J.; Sun, Dawei; McGarey, Donald J.; Wrenn, Shannon; Alexander, Laura M.; Martino, Maria Elena; Xing, Ye; Terhune, Jeffery S.

    2014-01-01

    ABSTRACT Since 2009, catfish farming in the southeastern United States has been severely impacted by a highly virulent and clonal population of Aeromonas hydrophila causing motile Aeromonas septicemia (MAS) in catfish. The possible origin of this newly emerged highly virulent A. hydrophila strain is unknown. In this study, we show using whole-genome sequencing and comparative genomics that A. hydrophila isolates from diseased grass carp in China and catfish in the United States have highly similar genomes. Our phylogenomic analyses suggest that U.S. catfish isolates emerged from A. hydrophila populations of Asian origin. Furthermore, we identified an A. hydrophila strain isolated in 2004 from a diseased catfish in Mississippi, prior to the onset of the major epidemic outbreaks in Alabama starting in 2009, with genomic characteristics that are intermediate between those of the Asian and Alabama fish isolates. Investigation of A. hydrophila strain virulence demonstrated that the isolate from the U.S. catfish epidemic is significantly more virulent to both channel catfish and grass carp than is the Chinese carp isolate. This study implicates the importation of fish or fishery products into the United States as the source of highly virulent A. hydrophila that has caused severe epidemic outbreaks in United States-farmed catfish and further demonstrates the potential for invasive animal species to disseminate bacterial pathogens worldwide. PMID:24895303

  2. Biochemical characteristics and virulence of environmental group F bacteria isolated in the United States.

    PubMed Central

    Seidler, R J; Allen, D A; Colwell, R R; Joseph, S W; Daily, O P

    1980-01-01

    Bacteria phenotypically resembling Aeromonas hydrophila, but requiring NaCl for growth, have been isolated form the New York Bight. The bacteria proved to be identical to group F organisms isolated from cases of human diarrhea in Indonesia and Bangladesh. Anaerogenic strains initiated responses in Y-1 tissue culture and rabbit ileal loop, consistent with those associated with cytotoxin- and enterotoxin-producing Aeromonas spp. strains. Separation on the basis of production of gas from glucose by group F strains was correlated with differences in mean guanine-plus-cytosine deoxyribonucleic acid base composition and in deoxyribonucleic acid relative reassociation. Both aerogenic and anaerogenic strains reassociated to a significantly greater extent with Vibrio spp. than with Aeromonas spp. and indeed should be considered a new species of the genus Vibrio. PMID:7425623

  3. Faecal contamination indicators, Salmonella, Vibrio and Aeromonas in water used for the irrigation of agricultural products.

    PubMed

    Pianietti, A; Sabatini, L; Bruscolini, F; Chiaverini, F; Cecchetti, G

    2004-04-01

    The faecal contamination indicators (total coliforms, faecal coliforms, Escherichia coli, enterococci) and the genera Salmonella, Vibrio, Aeromonas were investigated in water samples used for irrigation. During 4 months, 52 samples were taken. The methods used were: multiple tube fermentation method for faecal contamination indicators and membrane filtration techniques for salmonella, aeromonas and vibrio. Two samples were positive for Salmonella spp., fourteen for Aeromonas spp. and no samples for Vibrio spp. No correlation was found between aeromonas and the indicators of faecal contamination. Regarding Aeromonas spp., 21.6% of the strains were adhesive and 12.6% cytotoxic: this confirms the possible role of aeromonas in human pathologies. These results are important to determine the quality of irrigation water in relation to human health. In fact, the spray or sprinkler irrigation produces bioaerosol, which can contaminate the crops that are likely to be eaten uncooked. In addition, the flood or furrow irrigation represents a risk to field workers.

  4. Faecal contamination indicators, Salmonella, Vibrio and Aeromonas in water used for the irrigation of agricultural products.

    PubMed

    Pianietti, A; Sabatini, L; Bruscolini, F; Chiaverini, F; Cecchetti, G

    2004-04-01

    The faecal contamination indicators (total coliforms, faecal coliforms, Escherichia coli, enterococci) and the genera Salmonella, Vibrio, Aeromonas were investigated in water samples used for irrigation. During 4 months, 52 samples were taken. The methods used were: multiple tube fermentation method for faecal contamination indicators and membrane filtration techniques for salmonella, aeromonas and vibrio. Two samples were positive for Salmonella spp., fourteen for Aeromonas spp. and no samples for Vibrio spp. No correlation was found between aeromonas and the indicators of faecal contamination. Regarding Aeromonas spp., 21.6% of the strains were adhesive and 12.6% cytotoxic: this confirms the possible role of aeromonas in human pathologies. These results are important to determine the quality of irrigation water in relation to human health. In fact, the spray or sprinkler irrigation produces bioaerosol, which can contaminate the crops that are likely to be eaten uncooked. In addition, the flood or furrow irrigation represents a risk to field workers. PMID:15061497

  5. Molecular Characterization of Staphylococcus sciuri Strains Isolated from Humans

    PubMed Central

    Couto, Isabel; Sanches, Ilda Santos; Sá-Leão, Raquel; de Lencastre, Hermínia

    2000-01-01

    We previously characterized over 100 Staphylococcus sciuri isolates, mainly of animal origin, and found that they all carried a genetic element (S. sciuri mecA) closely related to the mecA gene of methicillin-resistant Staphylococcus aureus (MRSA) strains. We also found a few isolates that carried a second copy of the gene, identical to MRSA mecA. In this work, we analyzed a collection of 28 S. sciuri strains isolated from both healthy and hospitalized individuals. This was a relatively heterogeneous group, as inferred from the different sources, places, and dates of isolation and as confirmed by pulsed-field gel electrophoresis analysis. All strains carried the S. sciuri mecA copy, sustaining our previous proposal that this element belongs to the genetic background of S. sciuri. Moreover, 46% of the strains also carried the MRSA mecA copy. Only these strains showed significant levels of resistance to beta-lactams. Strikingly, the majority of the strains carrying the additional MRSA mecA copy were obtained from healthy individuals in an antibiotic-free environment. Most of the 28 strains were resistant to penicillin, intermediately resistant to clindamycin, and susceptible to tetracycline, erythromycin, and gentamicin. Resistance to these last three antibiotics was found in some strains only. The findings reported in this work confirmed the role of S. sciuri in the evolution of the mechanism of resistance to methicillin in staphylococci and suggested that this species (like the pathogenic staphylococci) may accumulate resistance markers for several classes of antibiotics. PMID:10699009

  6. Attachment of non-culturable toxigenic Vibrio cholerae O1 and non-O1 and Aeromonas spp. to the aquatic arthropod Gerris spinolae and plants in the River Ganga, Varanasi.

    PubMed

    Shukla, B N; Singh, D V; Sanyal, S C

    1995-10-01

    Non-cultivable, pathogenic O1 and non-O1 Vibrio cholerae and Aeromonas spp. were resuscitated from aquatic arthropods and plant homogenate respectively, by rabbit ileal loop (RIL) assay. These organisms adhered to the aquatic arthropod Gerris spinolae and various species of phytoplankton in the River Ganga, but failed to grow after direct inoculation on artificial media except for only 10 homogenates of the arthropod. The number of non-O1 V. cholerae and Aeromonas recovered on direct inoculation of G. spinolae homogenates were in the order of 10(5)-10(6) whereas those of the Ganga water were 10(2)-10(3) ml-1. A total of 119 strains of O1 and non-O1 V. cholerae and Aeromonas spp. (69 isolates from G. spinolae and 50 from aquatic plants) were recovered from the loop contents. The results indicate that production of the enzyme chitinase by O1 and non-O1 V. cholerae and Aeromonas spp. might facilitate their adsorption and multiplication on different species of zoo- and phyto-plankton. Most of the isolates were enterotoxic, haemolytic and resistant to different antibiotics. This study suggests that species of zoo- and phyto-planktons, until now not reported to be associated with O1 and non-O1 V. cholerae, may act as reservoirs of these organisms as well as different species of Aeromonas in a fresh-water riverine ecosystem.

  7. Draft Genome Sequence of Mariprofundus ferrooxydans Strain JV-1, Isolated from Loihi Seamount, Hawaii

    PubMed Central

    Fullerton, Heather; Hager, Kevin W.

    2015-01-01

    Mariprofundus ferrooxydans strain JV-1 was isolated in 1998 from Loihi Seamount, Hawaii. Here, we present the draft genome of strain JV-1, which shows similarity to other sequenced Mariprofundus isolates, strains PV-1 and M34. PMID:26450720

  8. Isolation of five Rubrobacter strains from biodeteriorated monuments.

    PubMed

    Laiz, L; Miller, A Z; Jurado, V; Akatova, E; Sanchez-Moral, S; Gonzalez, J M; Dionísio, A; Macedo, M F; Saiz-Jimenez, C

    2009-01-01

    In the last few years, the microbial colonisation of mural paintings in ancient monuments has been attracting the attention of microbiologists and conservators. The genus Rubrobacter is commonly found in biodeteriorated monuments, where it has been reported to cause rosy discolouration. However, to date, only three species of this genus have been isolated, all from thermophilic environments. In this paper, we studied three monuments: the Servilia and Postumio tombs in the Roman Necropolis of Carmona (Spain), and Vilar de Frades church (Portugal), in search of Rubrobacter strains. In all cases, biodeterioration and the formation of efflorescences were observed, and five Rubrobacter strains were isolated. These isolates showed different physiology and migration in denaturing gradient gel electrophoresis, suggesting they might represent new species within this genus. The isolates reproduced some biodeterioration processes in the laboratory and revealed their biomediation in crystal formation.

  9. Isolation of five Rubrobacter strains from biodeteriorated monuments.

    PubMed

    Laiz, L; Miller, A Z; Jurado, V; Akatova, E; Sanchez-Moral, S; Gonzalez, J M; Dionísio, A; Macedo, M F; Saiz-Jimenez, C

    2009-01-01

    In the last few years, the microbial colonisation of mural paintings in ancient monuments has been attracting the attention of microbiologists and conservators. The genus Rubrobacter is commonly found in biodeteriorated monuments, where it has been reported to cause rosy discolouration. However, to date, only three species of this genus have been isolated, all from thermophilic environments. In this paper, we studied three monuments: the Servilia and Postumio tombs in the Roman Necropolis of Carmona (Spain), and Vilar de Frades church (Portugal), in search of Rubrobacter strains. In all cases, biodeterioration and the formation of efflorescences were observed, and five Rubrobacter strains were isolated. These isolates showed different physiology and migration in denaturing gradient gel electrophoresis, suggesting they might represent new species within this genus. The isolates reproduced some biodeterioration processes in the laboratory and revealed their biomediation in crystal formation. PMID:18953520

  10. Isolation of five Rubrobacter strains from biodeteriorated monuments

    NASA Astrophysics Data System (ADS)

    Laiz, L.; Miller, A. Z.; Jurado, V.; Akatova, E.; Sanchez-Moral, S.; Gonzalez, J. M.; Dionísio, A.; Macedo, M. F.; Saiz-Jimenez, C.

    2009-01-01

    In the last few years, the microbial colonisation of mural paintings in ancient monuments has been attracting the attention of microbiologists and conservators. The genus Rubrobacter is commonly found in biodeteriorated monuments, where it has been reported to cause rosy discolouration. However, to date, only three species of this genus have been isolated, all from thermophilic environments. In this paper, we studied three monuments: the Servilia and Postumio tombs in the Roman Necropolis of Carmona (Spain), and Vilar de Frades church (Portugal), in search of Rubrobacter strains. In all cases, biodeterioration and the formation of efflorescences were observed, and five Rubrobacter strains were isolated. These isolates showed different physiology and migration in denaturing gradient gel electrophoresis, suggesting they might represent new species within this genus. The isolates reproduced some biodeterioration processes in the laboratory and revealed their biomediation in crystal formation.

  11. CHLORINE DISINFECTION OF AEROMONAS

    EPA Science Inventory

    The bacterial genus Aeromonas is currently listed on the USEPA's Candidate Contaminant List (CCL). Resistance to chemical disinfection is an essential aspect regarding all microbial groups listed on the CCL. This study was designed to determine the inactivation kinetics of Aeromo...

  12. Vibrio cholerae and Aeromonas: do they share a mutual host?

    PubMed

    Senderovich, Yigal; Gershtein, Yana; Halewa, Etti; Halpern, Malka

    2008-03-01

    Species of the genus Aeromonas are native inhabitants of aquatic environments and have recently been considered as an emergent human pathogen. It is estimated that aeromonads cause up to 13% of reported gastroenteritis cases in the United States. Although the autochthonous existence of Aeromonas in the aquatic environment has been established, its natural reservoir is as yet unknown. Chironomids are closely related to mosquitoes except they do not bite and they are the most widely distributed insects in freshwater. They infest drinking water systems in Israel and all over the world. Vibrio cholerae inhabit chironomids and are able to degrade their egg masses. The degradation of the egg masses is followed by failure of the eggs to hatch. In the current study, egg masses from a waste stabilization pond and a river in northern Israel were collected and cultured during a five-month period. Bacterial colonies were randomly chosen and checked for their egg mass degradation abilities. In addition to V. cholerae, most of the other isolates that had the ability to degrade the egg masses were identified as Aeromonas species, thus, demonstrating that Aeromonas species are natural inhabitants of chironomid egg masses. The following virulence-associated genes were detected in Aeromonas species that were isolated from chironomid egg masses: alt (78%); ahpB (76%); act/aerA/hlyA (65%); fla (59%); pla/lipH3/apl-1/lip (43%); and ast (2%). These findings indicate that the Aeromonas species inhabiting chironomid egg masses pose a potential health risk. Understanding the natural reservoir of Aeromonas will help to develop methods to monitor and control the bacteria in fresh and drinking water reservoirs and to better understand the relationships between chironomids, V. cholerae and Aeromonas populations.

  13. Aeromonas hydrophila in 2010: Characteristics of Alabama outbreaks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For a second year, epidemics associated with a virulent strain of Aeromonas hydrophila resulted in losses of hundreds of thousands of pounds of market size Alabama (AL) catfish. During this period, the Alabama Fish Farming Center diagnosed outbreaks of this strain of A. hydrophila on 25% (28/113) o...

  14. Classification of a Hypervirulent Aeromonas hydrophila Pathotype Responsible for Epidemic Outbreaks in Warm-Water Fishes

    PubMed Central

    Rasmussen-Ivey, Cody R.; Hossain, Mohammad J.; Odom, Sara E.; Terhune, Jeffery S.; Hemstreet, William G.; Shoemaker, Craig A.; Zhang, Dunhua; Xu, De-Hai; Griffin, Matt J.; Liu, Yong-Jie; Figueras, Maria J.; Santos, Scott R.; Newton, Joseph C.; Liles, Mark R.

    2016-01-01

    Lineages of hypervirulent Aeromonas hydrophila (vAh) are the cause of persistent outbreaks of motile Aeromonas septicemia in warm-water fishes worldwide. Over the last decade, this virulent lineage of A. hydrophila has resulted in annual losses of millions of tons of farmed carp and catfish in the People's Republic of China and the United States (US). Multiple lines of evidence indicate US catfish and Asian carp isolates of A. hydrophila affiliated with sequence type 251 (ST251) share a recent common ancestor. To address the genomic context for the putative intercontinental transfer and subsequent geographic spread of this pathogen, we conducted a core genome phylogenetic analysis on 61 Aeromonas spp. genomes, of which 40 were affiliated with A. hydrophila, with 26 identified as epidemic strains. Phylogenetic analyses indicate all ST251 strains form a coherent lineage affiliated with A. hydrophila. Within this lineage, conserved genetic loci unique to A. hydrophila were identified, with some genes present in consistently higher copy numbers than in non-epidemic A. hydrophila isolates. In addition, results from analyses of representative ST251 isolates support the conclusion that multiple lineages are present within US vAh isolated from Mississippi, whereas vAh isolated from Alabama appear clonal. This is the first report of genomic heterogeneity within US vAh isolates, with some Mississippi isolates showing closer affiliation with the Asian grass carp isolate ZC1 than other vAh isolated in the US. To evaluate the biological significance of the identified heterogeneity, comparative disease challenges were conducted with representatives of different vAh genotypes. These studies revealed that isolate ZC1 yielded significantly lower mortality in channel catfish, relative to Alabama and Mississippi vAh isolates. Like other Asian vAh isolates, the ZC1 lineage contains all core genes for a complete type VI secretion system (T6SS). In contrast, more virulent US isolates

  15. Emergence of CTX-M-3, TEM-1 and a new plasmid-mediated MOX-4 AmpC in a multiresistant Aeromonas caviae isolate from a patient with pneumonia.

    PubMed

    Ye, Ying; Xu, Xi-Hai; Li, Jia-Bin

    2010-07-01

    Aeromonas species rarely cause pulmonary infection. We report, for what is believed to be the first time, a case of severe pneumonia in a cancer patient caused by Aeromonas caviae. Detailed microbiological investigation revealed that this isolate carried three beta-lactamase-encoding genes (encoding MOX-4, CTX-M-3 and TEM-1) conferring resistance to all beta-lactams but imipenem. The beta-lactamase with a pI of 9.0 was transferred by conjugation and associated with a 7.3 kb plasmid, as demonstrated by Southern blot hybridization. Analysis of the nucleotide and amino acid sequences showed a new ampC gene that was closely related to those encoding the MOX-1, MOX-2 and MOX-3 beta-lactamases. This new plasmid-mediated AmpC beta-lactamase from China was named MOX-4. This is believed to be the first report of MOX-4, CTX-M-3 and TEM-1 beta-lactamases in a multiresistant A. caviae.

  16. Molecular characterisation of Xanthomonas strains isolated from aroids in Mauritius.

    PubMed

    Khoodoo, M H R; Sahin, F; Donmez, M F; Fakim, Y Jaufeerally

    2005-06-01

    Mauritius is one of the largest world producers of Anthurium cut flowers but outbreaks of bacterial blight have never been reported on the island. This work was about the characterisation and identification of bacterial strains isolated from Anthurium andreanum, Dieffenbachia maculata and Aglaonema simplex in Mauritius. Fifteen strains, that showed the morphological properties of Xanthomonas on conventional media, were tested on two semi-selective media (Esculin-trehalose and cellobiose-starch). ELISA tests using a panel of monoclonal antibodies were carried out and three out of 15 strains reacted with a Xanthomonas-specific monoclonal antibody (MAb XII). Analysis using four sets of ribosomal primers revealed that the same three Mauritius strains shared conserved PCR products with reference xanthomonads including virulent strains of Xanthomonas axonopodis pv. dieffenbachiae (Xad). BIOLOG tests and the Sherlock Microbial Identification system (MIDI) identified these three new strains at the species level as X. axonopodis. The complementary tests that were carried out clearly confirmed that the three strains are xanthomonads and, moreover, a DNA probe which showed specificity to Xad strains suggested that the three Mauritius strains are non-virulent forms of the pathogen causing Anthurium blight.

  17. Bioactivity characterization of Lactobacillus strains isolated from dairy products

    PubMed Central

    Haghshenas, Babak; Nami, Yousef; Haghshenas, Minoo; Abdullah, Norhafizah; Rosli, Rozita; Radiah, Dayang; Yari Khosroushahi, Ahmad

    2015-01-01

    This study aimed to find candidate strains of Lactobacillus isolated from sheep dairy products (yogurt and ewe colostrum) with probiotic and anticancer activity. A total of 100 samples were randomly collected from yogurt and colostrum and 125 lactic acid bacteria were isolated. Of these, 17 Lactobacillus strains belonging to five species (L. delbrueckii, L. plantarum, L. rhamnosus, L. paracasei, and L. casei) were identified. L. plantarum 17C and 13C, which isolated from colostrums, demonstrated remarkable results such as resistant to low pH and high concentrations of bile salts, susceptible to some antibiotics and good antimicrobial activity that candidate them as potential probiotics. Seven strains (1C, 5C, 12C, 13C, 17C, 7M, and 40M), the most resistant to simulated digestion, were further investigated to evaluate their capability to adhere to human intestinal Caco-2 cells. L. plantarum 17C was the most adherent strain. The bioactivity assessment of L. plantarum 17C showed anticancer effects via the induction of apoptosis on HT-29 human cancer cells and negligible side effects on one human epithelial normal cell line (FHs 74). The metabolites produced by this strain can be used as alternative pharmaceutical compounds with promising therapeutic indices because they are not cytotoxic to normal mammalian cells. PMID:26219634

  18. Isolation of Mycoplasma genitalium strains from the male urethra.

    PubMed Central

    Jensen, J S; Hansen, H T; Lind, K

    1996-01-01

    Mycoplasma genitalium is a human mycoplasma species which, on the basis of detection by PCR, has been incriminated as a cause of nongonococcal urethritis. Previously, only two strains from the urogenital tract and five strains from extragenital sites have been isolated. We have developed a method for the isolation of this fastidious microbe. M. genitalium from PCR-positive urethral specimens was initially propagated in Vero cell cultures grown in serum-free medium supplemented with Ultroser HY serum substitute. Growth was monitored by PCR. The M. genitalium strains grown in cell cultures could subsequently be subcultured in modified Friis's FF broth medium. Several passages in broth medium were required before growth on agar medium was attained. A total of 11 urethral specimens positive for M. genitalium by PCR from male patients with urethritis were investigated. Six strains were adapted to growth in broth medium, and four of these strains were cloned. Three specimens were overgrown by other mycoplasmas during propagation in the cell cultures. In only two PCR-positive specimens was propagation of M. genitalium unsuccessful. The use of cell culture combined with PCR monitoring of mycoplasmal growth may prove to be more widely applicable for the isolation of other fastidious mollicutes. PMID:8789002

  19. Bioactivity characterization of Lactobacillus strains isolated from dairy products.

    PubMed

    Haghshenas, Babak; Nami, Yousef; Haghshenas, Minoo; Abdullah, Norhafizah; Rosli, Rozita; Radiah, Dayang; Khosroushahi, Ahmad Yari

    2015-10-01

    This study aimed to find candidate strains of Lactobacillus isolated from sheep dairy products (yogurt and ewe colostrum) with probiotic and anticancer activity. A total of 100 samples were randomly collected from yogurt and colostrum and 125 lactic acid bacteria were isolated. Of these, 17 Lactobacillus strains belonging to five species (L. delbrueckii, L. plantarum, L. rhamnosus, L. paracasei, and L. casei) were identified. L. plantarum 17C and 13C, which isolated from colostrums, demonstrated remarkable results such as resistant to low pH and high concentrations of bile salts, susceptible to some antibiotics and good antimicrobial activity that candidate them as potential probiotics. Seven strains (1C, 5C, 12C, 13C, 17C, 7M, and 40M), the most resistant to simulated digestion, were further investigated to evaluate their capability to adhere to human intestinal Caco-2 cells. L. plantarum 17C was the most adherent strain. The bioactivity assessment of L. plantarum 17C showed anticancer effects via the induction of apoptosis on HT-29 human cancer cells and negligible side effects on one human epithelial normal cell line (FHs 74). The metabolites produced by this strain can be used as alternative pharmaceutical compounds with promising therapeutic indices because they are not cytotoxic to normal mammalian cells.

  20. Tannic acid degradation by Klebsiella strains isolated from goat feces

    PubMed Central

    Tahmourespour, Arezoo; Tabatabaee, Nooroldin; Khalkhali, Hossein; Amini, Imane

    2016-01-01

    Background and Objectives: Tannins are toxic polyphenols that either bind and precipitate or condense proteins. The high tannin content of some plants is the preliminary limitation of using them as a ruminant feed. So, the aim of this study was the isolation and characterization of tannic acid degrading bacterial strains from goat feces before and after feeding on Pistachio-Soft Hulls as tannin rich diet (TRD). Materials and Methods: Bacterial strains capable of utilizing tannic acid as sole carbon and energy source were isolated and characterized from goat feces before and after feeding on TRD. Tannase activity, maximum tolerable concentration and biodegradation potential were assessed. Results: Four tannase positive isolates were identified as Klebsiella pneumoniae. Isolated strains showed the maximum tolerable concentration of 64g/L of tannin. The tannic acid degradation percentage at a concentration of 15.0 g/L reached a maximum of 68% after 24 h incubation, and more than 98% after 72 h incubation. The pH of the medium also decreased along with tannic acid utilization. Conclusions: It is obvious that TRD induced adaptive responses. Thus, while the bacteria were able to degrade and detoxify the tannic acids, they had to adapt in the presence of high concentrations of tannic acid. So, these isolates have an amazing potential for application in bioremediation, waste water treatment, also reduction of tannins antinutritional effects in animal feeds. PMID:27092220

  1. Isolation of two Pseudomonas strains producing pseudomonic acid A.

    PubMed

    Fritz, Eva; Fekete, Agnes; Lintelmann, Jutta; Schmitt-Kopplin, Philipe; Meckenstock, Rainer U

    2009-02-01

    Two novel Pseudomonas strains were isolated from groundwater sediment samples. The strains showed resistance against the antibiotics tetracycline, cephalothin, nisin, vancomycin, nalidixic acid, erythromycin, lincomycin, and penicillin and grew at temperatures between 15 and 37 degrees C and pH values from 4 to 10 with a maximum at pH 7 to 10. The 16S ribosomal RNA gene sequences and the substrate spectrum of the isolates revealed that the two strains belonged to the Pseudomonas fluorescens group. The supernatants of both strains had an antibiotic effect against Gram-positive bacteria and one Gram-negative strain. The effective substance was produced under standard cultivation conditions without special inducer molecules or special medium composition. The antibiotically active compound was identified as pseudomonic acid A by off-line high performance liquid chromatography (HPLC) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The measurement on ultra performance liquid chromatography (UPLC, UV-vis detection) confirmed the determination of pseudomonic acid A which was produced by both strains at 1.7-3.5mg/l. Our findings indicate that the ability to produce the antibiotic pseudomonic acid A (Mupirocin) is more spread among the pseudomonads then anticipated from the only producer known so far. PMID:19070447

  2. Probiotic characteristics of Lactobacillus fermentum strains isolated from tulum cheese.

    PubMed

    Tulumoğlu, Şener; Kaya, Halil İbrahim; Şimşek, Ömer

    2014-12-01

    The aim of this study was to characterize the probiotic characteristics of Lactobacillus fermentum strains isolated from Tulum cheese. Seven L. fermentum strains were selected among the isolated and identified lactobacillus strains due to their abundance. When the gastric condition was considered, L. fermentum LP3 and LP4 were able to tolerate pH 2.5 and 1% bile salt. All L. fermentum strains had similar enzymatic activity and antibiotic resistance pattern but the highest antagonistic effect was detected within LP3, LP4 and LP6. Cholesterol assimilation amount of L. fermentum strains ranged between 12.1 and 45.3% in MRS and 20.7-71.1% in MRS with bile. The highest cholesterol assimilation in MRS and MRS with bile was occurred by LP3 and LP4, respectively. L. fermentum LP2 adhered to caco-2 cells more than Lactobacillus rhamnosus LGG where LP3, LP4 and LP5 adhered at similar level. In conclusion, L. fermentum LP3 and LP4 fulfilled sufficient criteria to be probiotics for use as a starter culture in the production of tulum cheese or other dairy products. Also this study indicated that some food-associated Lactobacillus strains non-predominant for gut biota have significant probiotic potential.

  3. Bacteremia due to extended-spectrum-β-lactamase-producing Aeromonas spp. at a medical center in Southern Taiwan.

    PubMed

    Wu, Chi-Jung; Chuang, Yin-Ching; Lee, Mei-Feng; Lee, Chin-Chi; Lee, Hsin-Chun; Lee, Nan-Yao; Chang, Chia-Ming; Chen, Po-Lin; Lin, Yu-Tzu; Yan, Jing-Jou; Ko, Wen-Chien

    2011-12-01

    Although extended-spectrum-β-lactamase (ESBL)-producing aeromonads have been increasingly reported in recent years, most of them were isolates from case reports or environmental isolates. To investigate the prevalence of ESBL producers among Aeromonas blood isolates and the genes encoding ESBLs, consecutive nonduplicate Aeromonas blood isolates collected at a medical center in southern Taiwan from March 2004 to December 2008 were studied. The ESBL phenotypes were examined by clavulanate combination disk test and the cefepime-clavulanate ESBL Etest. The presence of ESBL-encoding genes, including bla(TEM), bla(PER), bla(CTX-M), and bla(SHV) genes, was evaluated by PCR and sequence analysis. The results showed that 4 (2.6%) of 156 Aeromonas blood isolates, 1 Aeromonas hydrophila isolate and 3 Aeromonas caviae isolates, expressed an ESBL-producing phenotype. The ESBL gene in two A. caviae isolates was bla(PER-3), which was located in both chromosomes and plasmids, as demonstrated by Southern hybridization. Of four patients with ESBL-producing Aeromonas bacteremia, two presented with catheter-related phlebitis and the other two with primary bacteremia. Three patients had been treated with initial noncarbapenem β-lactams for 5 to 10 days, and all survived. In conclusion, ESBL producers exist among Aeromonas blood isolates, and clinical suspicion of ESBL production should be raised in treating infections due to cefotaxime-resistant Aeromonas isolates.

  4. Bacteremia Due to Extended-Spectrum-β-Lactamase-Producing Aeromonas spp. at a Medical Center in Southern Taiwan▿

    PubMed Central

    Wu, Chi-Jung; Chuang, Yin-Ching; Lee, Mei-Feng; Lee, Chin-Chi; Lee, Hsin-Chun; Lee, Nan-Yao; Chang, Chia-Ming; Chen, Po-Lin; Lin, Yu-Tzu; Yan, Jing-Jou; Ko, Wen-Chien

    2011-01-01

    Although extended-spectrum-β-lactamase (ESBL)-producing aeromonads have been increasingly reported in recent years, most of them were isolates from case reports or environmental isolates. To investigate the prevalence of ESBL producers among Aeromonas blood isolates and the genes encoding ESBLs, consecutive nonduplicate Aeromonas blood isolates collected at a medical center in southern Taiwan from March 2004 to December 2008 were studied. The ESBL phenotypes were examined by clavulanate combination disk test and the cefepime-clavulanate ESBL Etest. The presence of ESBL-encoding genes, including blaTEM, blaPER, blaCTX-M, and blaSHV genes, was evaluated by PCR and sequence analysis. The results showed that 4 (2.6%) of 156 Aeromonas blood isolates, 1 Aeromonas hydrophila isolate and 3 Aeromonas caviae isolates, expressed an ESBL-producing phenotype. The ESBL gene in two A. caviae isolates was blaPER-3, which was located in both chromosomes and plasmids, as demonstrated by Southern hybridization. Of four patients with ESBL-producing Aeromonas bacteremia, two presented with catheter-related phlebitis and the other two with primary bacteremia. Three patients had been treated with initial noncarbapenem β-lactams for 5 to 10 days, and all survived. In conclusion, ESBL producers exist among Aeromonas blood isolates, and clinical suspicion of ESBL production should be raised in treating infections due to cefotaxime-resistant Aeromonas isolates. PMID:21968366

  5. Pathogenic Potential of Saccharomyces Strains Isolated from Dietary Supplements

    PubMed Central

    Monteoliva, Lucía; Querol, Amparo; Molina, María; Fernández-Espinar, María T.

    2014-01-01

    Saccharomyces cerevisiae plays a beneficial role in health because of its intrinsic nutritional value and bio-functional properties, which is why it is also used as a dietary supplement. However, the perception that S. cerevisiae is harmless has changed due to an increasing number of infections caused by this yeast. Given this scenario, we have tested whether viable strains contained in dietary supplements displayed virulence-associated phenotypic traits that could contribute to virulence in humans. We have also performed an in vivo study of the pathogenic potential of these strains using a murine model of systemic infection by intravenous inoculation. A total of 5 strains were isolated from 22 commercial products and tested. Results highlight one strain (D14) in terms of burden levels in brains and kidneys and ability to cause death, whereas the other two strains (D2 and D4) were considered of low virulence. Our results suggest a strong relationship between some of the virulence-associated phenotypic traits (ability to grow at 39°C and pseudohyphal growth) and the in vivo virulence in a mouse model of intravenous inoculation for isolates under study. The isolate displaying greatest virulence (D14) was evaluated in an experimental murine model of gastrointestinal infection with immunosuppression and disruption of mucosal integrity, which are common risk factors for developing infection in humans, and results were compared with an avirulent strain (D23). We showed that D14 was able to spread to mesenteric nodes and distant organs under these conditions. Given the widespread consumption of dietary supplements, we recommend only safe strains be used. PMID:24879417

  6. Pathogenic potential of Saccharomyces strains isolated from dietary supplements.

    PubMed

    Llopis, Silvia; Hernández-Haro, Carolina; Monteoliva, Lucía; Querol, Amparo; Molina, María; Fernández-Espinar, María T

    2014-01-01

    Saccharomyces cerevisiae plays a beneficial role in health because of its intrinsic nutritional value and bio-functional properties, which is why it is also used as a dietary supplement. However, the perception that S. cerevisiae is harmless has changed due to an increasing number of infections caused by this yeast. Given this scenario, we have tested whether viable strains contained in dietary supplements displayed virulence-associated phenotypic traits that could contribute to virulence in humans. We have also performed an in vivo study of the pathogenic potential of these strains using a murine model of systemic infection by intravenous inoculation. A total of 5 strains were isolated from 22 commercial products and tested. Results highlight one strain (D14) in terms of burden levels in brains and kidneys and ability to cause death, whereas the other two strains (D2 and D4) were considered of low virulence. Our results suggest a strong relationship between some of the virulence-associated phenotypic traits (ability to grow at 39°C and pseudohyphal growth) and the in vivo virulence in a mouse model of intravenous inoculation for isolates under study. The isolate displaying greatest virulence (D14) was evaluated in an experimental murine model of gastrointestinal infection with immunosuppression and disruption of mucosal integrity, which are common risk factors for developing infection in humans, and results were compared with an avirulent strain (D23). We showed that D14 was able to spread to mesenteric nodes and distant organs under these conditions. Given the widespread consumption of dietary supplements, we recommend only safe strains be used. PMID:24879417

  7. Skin and soft-tissue infections caused by Aeromonas species.

    PubMed

    Chao, C M; Lai, C C; Tang, H J; Ko, W C; Hsueh, P-R

    2013-04-01

    This study investigated the clinical characteristics of patients with skin and soft-tissue infections (SSTIs) due to Aeromonas species. Patients with SSTIs caused by Aeromonas species during the period from January 2009 to December 2011 were identified from a computerized database of a regional hospital in southern Taiwan. The medical records of these patients were retrospectively reviewed. A total of 129 patients with SSTIs due to Aeromonas species were identified. A. hydrophila (n = 77, 59.7 %) was the most common pathogen, followed by A. veronii biovar sobria (n = 22, 17.1 %), A. veronii biovar veronii (n = 20, 15.5 %), A. caviae (n = 9, 7.0 %), and A. schubertii (n = 1, 0.8 %). The most common isolates obtained from patients with polymicrobial infections were Klebsiella species (n = 33), followed by Enterococcus spp. (n = 24), Enterobacter spp. (n = 21), Escherichia coli (n = 17), Staphylococcus spp. (n = 17), Streptococcus spp. (n = 17), and Acinetobacter spp. (n = 15). Liver cirrhosis and concomitant bacteremia were more common among patients with monomicrobial Aeromonas SSTIs than among patients with polymicrobial SSTIs. Nine (7 %) patients required limb amputations. The in-hospital mortality rate was 1.6 %. In conclusion, Aeromonas species should be considered as important causative pathogens of SSTIs, and most infections are polymicrobial. In addition, the clinical presentation differs markedly between patients with monomicrobial and those with polymicrobial Aeromonas SSTIs.

  8. Genotypic and phenotypic identification of Aeromonas species and CphA-mediated carbapenem resistance in Queensland, Australia.

    PubMed

    Sinclair, Holly A; Heney, Claire; Sidjabat, Hanna E; George, Narelle M; Bergh, Haakon; Anuj, Snehal N; Nimmo, Graeme R; Paterson, David L

    2016-05-01

    Infection caused by Aeromonas spp. ranges from superficial wound infection to life-threatening septicemia. Carbapenem resistance due to metallo-beta-lactamase, CphA encoded by the cphA gene, is a significant problem. This study defines Aeromonas spp. causing clinical disease in Queensland, Australia. Phenotypic tests for carbapenemase detection were assessed. One hundred Aeromonas isolates from blood (22), wound (46), sterile sites (11), stool (18), eye (2), and sputum (1) were characterized by rpoB and gyrB sequencing. Meropenem susceptibility by VITEK2, disk diffusion, and E-test MIC were determined. Carbapenemase production was assessed by Carba NP test and cphA by PCR. Gene sequencing identified isolates as Aeromonas dhakensis (39), Aeromonas veronii (21), Aeromonas hydrophila (20), Aeromonas caviae (14), Aeromonas jandaei (4), Aeromonas bestiarum (1), and Aeromonas sanarellii (1). Disk diffusion and E-test failed to detect resistance in isolates with presence of cphA. Carba NP was performed with 97.4% sensitivity and 95.7% specificity. Carbapenem resistance gene cphA was detected in A. veronii (21; 100%), A. hydrophila (18; 90%), A. dhakensis (34; 87.2%), A. jandaei (3; 75%), and A. bestiarum (1; 100%) but not A. caviae. We found that A. dhakensis was the predominant species, a previously unrecognized pathogen in this region.

  9. Aeromonas in Arab countries: 1995-2014.

    PubMed

    Ghenghesh, Khalifa Sifaw; Rahouma, Amal; Zorgani, Abdulaziz; Tawil, Khaled; Al Tomi, Abdurazzaq; Franka, Ezzadin

    2015-10-01

    The aim of this review is to provide information on the prevalence, clinical syndromes, and antimicrobial resistance and therapy of Aeromonas spp. infections in Arab countries. The data were obtained by an English language literature search from 1995 to 2014 of Medline and PubMed for papers using the search terms "Aeromonas+name of Arab country (i.e. Algeria, Egypt, etc.)". Additional data were obtained from a Google search using the aforementioned terms. The organisms have been reported from diarrheal children, patients with cholera-like diarrhea, an outbreak of acute gastroenteritis and from different types of animals, foods and water source in several Arab countries in the Middle East and North Africa with predominance of A. hydrophila, A. caviae and A. sobria. Using molecular techniques few studies reported genes encoding several toxins from aeromonads isolated from different sources. Among the antimicrobials examined in the present review third generation cephalosporins, fluoroquinolones and aminoglycosides showed excellent activity and can be employed in the treatment of Aeromonas-associated human infections in Arabic countries. Whenever possible, treatment should be guided by the susceptibility testing results of the isolated organism. In the future, studies employing molecular testing methods are required to provide data on circulating genospecies and their modes of transmission in the community, and on their mechanisms of resistance to antimicrobials. Microbiology laboratories and research centers are encouraged to look for these organisms in clinical, food and water sources to attain a better understanding of the public health risks from these organisms in Arab countries.

  10. A Novel Strain D5 Isolated from Acacia confusa

    PubMed Central

    Huang, Baoling; Lv, Chengqun; Zhao, Yili; Huang, Rong

    2012-01-01

    We isolated a novel strain D5 from nodules of Acacia confusa. Under strict sterile conditions the strain could successfully nodulate Acacia confusa, A. crassicarpa and A. mangium, with nitrogenase activity ranging from 18.90 to 19.86 nmol·g−1·min−1. In the phylogenetic tree based on a complete 16S rRNA gene sequence, the sequence of strain D5 shared 99% homology with that of four species of genus Pseudomonas. The 685 bp nodA fragment amplified from strain D5 shared 95% homology with the nodA sequence of 9 species of genus Bradyrhizobium, with a genetic distance of 0.01682. The 740 bp nifH gene fragment was amplified from strain D5. This strain D5 nifH gene and Bradyrhizobium spp. formed a branch, showing 98% homology and a genetic distance of 0. The homology between this branch and the Bradyrhizobium spp. DG in another branch was 99%, with a genetic distance of 0.007906. These results indicate that this strain D5 is a new type of nitrogen-fixing bacterium. PMID:23166618

  11. Mannanoligosaccharide agglutination by Salmonella enterica strains isolated from carrier pigs

    PubMed Central

    Borowsky, Luciane; Corção, Gertrudes; Cardoso, Marisa

    2009-01-01

    Type-1 fimbriae are associated with most Salmonella enterica serovars and are an essential factor for host colonization. Mannanoligosaccharides (MOS), a prebiotic that is agglutinated by type-1 fimbriae, are proposed for the control of enterobacteria colonization and may be an alternative to Salmonella control in pigs. The aim of this study was to evaluate the capability of porcine Salmonella strains to adhere to MOS in vitro. A total of 108 strains of Salmonella sp. isolated from carrier pigs were evaluated for the amplification of fimA and fimH genes, agglutination of MOS and hemagglutination. In all tested strains, amplicons of expected size were detected for both fimA and fimH gene. In the hemagglutination assays, 31 (28.7%) strains presented mannose–sensitive agglutination of erythrocytes, indicating that the strains were expressing type-1 fimbriae. Considering only strains expressing the type-1 fimbriae, 23 (74.2%) presented a strong agglutination of MOS, 3 (9.6%) a weak reaction and 5 (16.2%) none. The results indicate that Salmonella enterica strains expressing type-1 fimbriae can agglutinate effectively in vitro to MOS. PMID:24031388

  12. Postmating Reproductive isolation between strains of Drosophila willistoni

    PubMed Central

    Mardiros, Xian B.; Park, Ronni; Clifton, Bryan; Grewal, Gurman; Khizar, Amina K.; Markow, Therese A.; Ranz, José M.; Civetta, Alberto

    2016-01-01

    ABSTRACT Speciation can occur through the presence of reproductive isolation barriers that impede mating, restrict cross-fertilization, or render inviable/sterile hybrid progeny. The D. willistoni subgroup is ideally suited for studies of speciation, with examples of both allopatry and sympatry, a range of isolation barriers, and the availability of one species complete genome sequence to facilitate genetic studies of divergence. D. w. willistoni has the largest geographic distribution among members of the Drosophila willistoni subgroup, spanning from Argentina to the southern United States, including the Caribbean islands. A subspecies of D. w. willistoni, D. w. quechua, is geographically separated by the Andes mountain range and has evolved unidirectional sterility, in that only male offspring of D. w. quechua females × D. w. willistoni males are sterile. Whether D. w. willistoni flies residing east of the Andes belong to one or more D. willistoni subspecies remains unresolved. Here we perform fecundity assays and show that F1 hybrid males produced from crosses between different strains found in Central America, North America, and northern Caribbean islands are reproductively isolated from South American and southern Caribbean island strains as a result of unidirectional hybrid male sterility. Our results show the existence of a reproductive isolation barrier between the northern and southern strains and suggest a subdivision of the previously identified D. willistoni willistoni species into 2 new subspecies. PMID:27268100

  13. Postmating Reproductive isolation between strains of Drosophila willistoni.

    PubMed

    Mardiros, Xian B; Park, Ronni; Clifton, Bryan; Grewal, Gurman; Khizar, Amina K; Markow, Therese A; Ranz, José M; Civetta, Alberto

    2016-10-01

    Speciation can occur through the presence of reproductive isolation barriers that impede mating, restrict cross-fertilization, or render inviable/sterile hybrid progeny. The D. willistoni subgroup is ideally suited for studies of speciation, with examples of both allopatry and sympatry, a range of isolation barriers, and the availability of one species complete genome sequence to facilitate genetic studies of divergence. D. w. willistoni has the largest geographic distribution among members of the Drosophila willistoni subgroup, spanning from Argentina to the southern United States, including the Caribbean islands. A subspecies of D. w. willistoni, D. w. quechua, is geographically separated by the Andes mountain range and has evolved unidirectional sterility, in that only male offspring of D. w. quechua females × D. w. willistoni males are sterile. Whether D. w. willistoni flies residing east of the Andes belong to one or more D. willistoni subspecies remains unresolved. Here we perform fecundity assays and show that F1 hybrid males produced from crosses between different strains found in Central America, North America, and northern Caribbean islands are reproductively isolated from South American and southern Caribbean island strains as a result of unidirectional hybrid male sterility. Our results show the existence of a reproductive isolation barrier between the northern and southern strains and suggest a subdivision of the previously identified D. willistoni willistoni species into 2 new subspecies. PMID:27268100

  14. Development and validation of glycoprotein-based native-subunit vaccine for fish against Aeromonas hydrophila.

    PubMed

    Çiftci, A; Onuk, E E; Çiftci, G; Fındık, A; Söğüt, M Ü; Didinen, B I; Aksoy, A; Üstünakın, K; Gülhan, T; Balta, F; Altun, S

    2016-08-01

    Aeromonas hydrophila is known to be causative agent of an infection named as Bacterial haemorrhagic septicaemia or red pest in freshwater fish. The aim of this study was to develop and validate the glycoprotein-based fish vaccine against Aeromonas hydrophila. For this aim, after identification and characterization of A. hydrophila isolates from fish farms, one A. hydrophila isolate was selected as vaccine strain. Antigenic glycoproteins of this vaccine strain were determined by Western blotting and glycan detection kit. The connection types of these glycoproteins were examined by glycoprotein differentiation kit. Two glycoproteins, molecular weights of 19 and 38 kDa, with SNA connection type were selected for use in vaccination trials. After their purification by SNA-specific lectin and size-exclusion chromatography, protection studies with purified proteins were performed. For challenge trials, four experimental fish groups were designated: Group I (with montanide), Group II (with montanide and ginseng), Group III [with Al(OH)3 ] and Group IV [with Al(OH)3 and ginseng]. The survival ratings of fish were determined, and protection was calculated as 21.56%, 29.41%, 69.83% and 78.88% in groups I, II, III and IV, respectively. In conclusion, A. hydrophila glycoproteins with Al(OH)3 and ginseng could be used as a safe and effective vaccine for fish. PMID:27144782

  15. Isolation, characterization, and genetics of pentachlorophenol-degrading Flavobacterium strains

    SciTech Connect

    Saber, D.L.

    1987-01-01

    Bacteria able to mineralize 100-200 ppm of pentachlorophenol (PCP) were isolated by selective enrichment from PCP-contaminated soil from 3 geographic areas in Minnesota. Sampling areas were separated from each other by up to 185 miles; history and level of contamination with a variety of compounds varied between sites. Pure cultures of bacteria were selected for further characterization based on growth properties, site of isolation, and return of radiolabeled PCP as /sup 14/CO/sub 2/ in initial serum bottle experiments. Although differing somewhat in their response to various biochemical and biophysical tests, all strains were Gram-negative, oxidase-, catalase-, and phosphatase-positive, not motile, grow as yellow colonies on solid medium, limited in their use of single carbon sources,and ranged in mol% G + C of DNA between 58.8-63,8%. All strains were assigned to the genus Flavobacterium.

  16. Bacillus amyloliquefaciens G1: A Potential Antagonistic Bacterium against Eel-Pathogenic Aeromonas hydrophila

    PubMed Central

    Cao, Haipeng; He, Shan; Wei, Ruopeng; Diong, Marek; Lu, Liqun

    2011-01-01

    Recent studies have revealed that the use of probiotics is an alternative to control marine aeromonas. However, few probiotics are available against Aeromonas hydrophila infections in eels. In the present study, a potential antagonistic strain G1 against the eel-pathogenic A. hydrophila was isolated from sediment underlying brackish water. Its extracellular products with antibacterial activities were shown to be stable under wide range of pH, temperature, and proteinase K. It was initially identified as Bacillus amyloliquefaciens using API identification kits and confirmed to be B. amyloliquefaciens strain (GenBank accession number DQ422953) by phylogenetic analysis. In addition, it was shown to be safe for mammalians, had a wide anti-A. hydrophila spectrum, and exhibited significant effects on inhibiting the growth of the eel-pathogenic A. hydrophila both in vitro and in vivo. To the best of our knowledge, this is the first report on a promising antagonistic Bacillus amyloliquefaciens strain from brackish water sediment against eel-pathogenic A. hydrophila. PMID:21754944

  17. [Frequency of isolation and susceptibility to antibiotics of Escherichia coli strains isolated from blood].

    PubMed

    Białucha, Agata; Budzyńska, Anna; Kozuszko, Sylwia; Gospodarek, Eugenia

    2010-01-01

    The aim of our study was the analysis of Escherichia coli strains obtained from patients of University Hospital No 1 of dr A. Jurasz Collegium Medicum of L. Rydygier in Bydgoszcz Nicolaus Copernicus University in Toruń and State Infectious Diseases Observatory Hospital of T. Browicz in Bydgoszcz, between 2007 and 2010. Among all microorganisms isolated from blood was 8.7% E. coli strains and 45.1% of all rods from Enterobacteriaceae family. Number of E. coli isolations from positive blood samples was: 64 in 2007, 69 in 2008, 77 in 2009 and 26 in the first half of 2010 year. The highest percentage of E. coli strains were obtained from patients of the Transplantology and Surgery Clinic (16.1%), the Nephrology and Internal Diseases Clinic with the Dialysis Centre (14.0%), the Pediatric, Hematology and Oncology Clinic (13.6%) and the Anesthesiology and Intensive Care Clinic (13.6%). All analysed strains were susceptible to carbapenems, amikacin and tygecycline. The highest percentage of resistant strains were observed to ampicillin (70.7%), piperacillin (43.9%), tetracycline (42.8%) and doxycycline (38.8%). During four years of study 4 (6.3%), one, three and two E. coli strains with ESBL were isolated, respectively.

  18. Trigonella foenum-graceum (Seed) Extract Interferes with Quorum Sensing Regulated Traits and Biofilm Formation in the Strains of Pseudomonas aeruginosa and Aeromonas hydrophila.

    PubMed

    Husain, Fohad Mabood; Ahmad, Iqbal; Khan, Mohd Shahnawaz; Al-Shabib, Nasser Abdulatif

    2015-01-01

    Trigonella foenum-graecum L. (Fenugreek) is an important plant of the Leguminosae family known to have medicinal properties. However, fraction based antiquorum sensing and antibiofilm activities have not been reported from this plant. In the present study T. foenum-graecum seed extract was sequentially fractionated and sub-MICs were tested for above activities. The methanol fraction of the extract demonstrated significant inhibition of AHL regulated virulence factors: protease, LasB elastase, pyocyanin production, chitinase, EPS, and swarming motility in Pseudomonas aeruginosa PAO1 and PAF79. Further, QS dependent virulence factor in the aquatic pathogen Aeromonas hydrophila WAF38 was also reduced. Application of T. foenum-graecum seed extract to PAO1, PAF79, and WAF38 decreased the biofilm forming abilities of the pathogens by significant levels. The extract also exhibited reduced AHL levels and subsequent downregulation of lasB gene. In vivo study showed an enhanced survival of PAO1-preinfected C. elegans after treatment with extract at 1 mg/mL. Further, the major compound detected by GC-MS, caffeine, reduced the production of QS regulated virulence factors and biofilm at 200 µg/mL concentration indicating its role in the activity of the methanol extract. The results of the present study reveal the potential anti-QS and antibiofilm property of T. foenum-graceum extract and caffeine. PMID:26000026

  19. Trigonella foenum-graceum (Seed) Extract Interferes with Quorum Sensing Regulated Traits and Biofilm Formation in the Strains of Pseudomonas aeruginosa and Aeromonas hydrophila

    PubMed Central

    Husain, Fohad Mabood; Ahmad, Iqbal; Khan, Mohd Shahnawaz; Al-Shabib, Nasser Abdulatif

    2015-01-01

    Trigonella foenum-graecum L. (Fenugreek) is an important plant of the Leguminosae family known to have medicinal properties. However, fraction based antiquorum sensing and antibiofilm activities have not been reported from this plant. In the present study T. foenum-graecum seed extract was sequentially fractionated and sub-MICs were tested for above activities. The methanol fraction of the extract demonstrated significant inhibition of AHL regulated virulence factors: protease, LasB elastase, pyocyanin production, chitinase, EPS, and swarming motility in Pseudomonas aeruginosa PAO1 and PAF79. Further, QS dependent virulence factor in the aquatic pathogen Aeromonas hydrophila WAF38 was also reduced. Application of T. foenum-graecum seed extract to PAO1, PAF79, and WAF38 decreased the biofilm forming abilities of the pathogens by significant levels. The extract also exhibited reduced AHL levels and subsequent downregulation of lasB gene. In vivo study showed an enhanced survival of PAO1-preinfected C. elegans after treatment with extract at 1 mg/mL. Further, the major compound detected by GC-MS, caffeine, reduced the production of QS regulated virulence factors and biofilm at 200 µg/mL concentration indicating its role in the activity of the methanol extract. The results of the present study reveal the potential anti-QS and antibiofilm property of T. foenum-graceum extract and caffeine. PMID:26000026

  20. Probiotic potential of Enterococcus faecalis strains isolated from meconium

    PubMed Central

    Al Atya, Ahmed K.; Drider-Hadiouche, Karima; Ravallec, Rozenn; Silvain, Amadine; Vachee, Anne; Drider, Djamel

    2015-01-01

    107 bacterial isolates with Gram positive staining and negative catalase activity, presumably assumed as lactic acid bacteria, were isolated from samples of meconium of 6 donors at Roubaix hospital, in the north of France. All these bacterial isolates were identified by MALDI-TOF mass spectrometry as Enterococcus faecalis. However, only six isolates among which E. faecalis 14, E. faecalis 28, E. faecalis 90, E. faecalis 97, and E. faecalis 101 (obtained from donor 3), and E. faecalis 93 (obtained from donor 5) were active against some Gram-negative bacteria and Gram-positive bacteria , through production of lactic acid, and bacteriocin like inhibitory substances. The identification of these isolates was confirmed by 16rDNA sequencing and their genetic relatedness was established by REP-PCR and pulsed field gel electrophoresis methods. Importantly, the aforementioned antagonistic isolates were sensitive to various classes of antibiotics tested, exhibited high scores of coaggregation and hydrophobicity, and were not hemolytic. Taken together, these properties render these strains as potential candidates for probiotic applications. PMID:25883590

  1. [Differentiation of bacteria of the genus Aeromonas from other representatives of the Vibrionaceae family on the basis of their DNA].

    PubMed

    Levanova, G F; Lavrovskaia, V M; Shvetsov, Iu P

    1980-08-01

    By comparing the data on the nucleotide composition of DNA, and the phenotypic characteristics, most of the representatives of the genus Aeromonas were clearly differentiated from NAG vibrios isolated in the process of sanitary control of the environment. At the same time some microorganisms with the Aeromonas phenotype, but having a different DNA structure were detected. The use of the method of molecular DNA hybridization indicated that these bacteria were the taxons analogous to the genus Aeromonas.

  2. Aeromonas dhakensis, an Increasingly Recognized Human Pathogen

    PubMed Central

    Chen, Po-Lin; Lamy, Brigitte; Ko, Wen-Chien

    2016-01-01

    Aeromonas dhakensis was first isolated from children with diarrhea in Dhaka, Bangladesh and described in 2002. In the past decade, increasing evidence indicate this species is widely distributed in the environment and can cause a variety of infections both in human and animals, especially in coastal areas. A. dhakensis is often misidentified as A. hydrophila, A. veronii, or A. caviae by commercial phenotypic tests in the clinical laboratory. Correct identification relies on molecular methods. Increasingly used matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) may be able to identify Aeromonas specie rapidly and accurately. A. dhakensis has shown its potent virulence in different animal models and clinical infections. Although several virulence factors had been reported, no single mechanism is conclusive. Characteristically A. dhakensis is the principal species causing soft tissue infection and bacteremia, especially among patients with liver cirrhosis or malignancy. Of note, A. dhakensis bacteremia is more lethal than bacteremia due to other Aeromonas species. The role of this species in gastroenteritis remains controversial. Third generation cephalosporins and carbapenems should be used cautiously in the treatment of severe A. dhakensis infection due to the presence of AmpC ββ-lactamase and metallo-β-lactamase genes, and optimal regimens may be cefepime or fluoroquinolones. Studies of bacterial virulence factors and associated host responses may provide the chance to understand the heterogeneous virulence between species. The hypothesis A. dhakensis with varied geographic prevalence and enhanced virulence that compared to other Aeromonas species warrants more investigations. PMID:27303382

  3. Biodegradation of acetochlor by a newly isolated Pseudomonas strain.

    PubMed

    Luo, Wei; Gu, Qiuya; Chen, Wenting; Zhu, Xiangcheng; Duan, Zhibing; Yu, Xiaobin

    2015-05-01

    A novel microbial strain JD115 capable of degrading acetochlor was isolated from the sludge of acetochlor manufacture and was identified as Pseudomonas aeruginosa species. This strain was able to grow on acetochlor as the sole source of both carbon and nitrogen. The biodegradation of acetochlor by strain JD115 could be described either by the pseudo-first-order or by the second-order kinetics models, while the latter gave a better performance. The strain optimally degraded acetochlor at a pH value of 7.0 and a temperature of 37 °C. Additional nutriments could greatly enhance the degradation rate of acetochlor up to 95.4% in the presence of 50 mg acetochlor l(-1). The metabolite analyses by GC-MS presumed that catechol was an intermediate product of acetochlor, which was finally degraded for 5 days of incubation. This study highlights the potential use of this strain for the bioremediation of an acetochlor-polluted environment.

  4. Identification of nif genes in N2-fixing bacterial strains isolated from rice fields along the Yangtze River Plain.

    PubMed

    Xie, Guang Hui; Cui, Zongjun; Yu, Jun; Yan, Jing; Hai, Weili; Steinberger, Yosef

    2006-01-01

    The aim of this research was to identify nifH and nifHDKYE ' genes in twenty strains of N2-fixing heterotrophic bacteria isolated from rice fields in the Yangtze River Plain. Southern hybridization of the total DNA from each strain was performed with the Klebsiella pneumoniae nifHDKYE ' gene probe (6.2 kb Eco RI fragment from pSA30) and the Azospirillum brasilense nifH gene probe (0.6 kb Eco RI-Hin dIII fragment from pHU8). We found that Eco RI fragments of total DNA from Aeromonas hydrophila HY2, Bacillus azotoformans FD, Bacillus licheniformis NCH1, NCH5, WH4, Bacillus brevis NC2, Bacillus pumilus NC12, Bacillus cereus NCH2, Citrobacter freundii HY5, HY9, Derxia gummosa HZ5, Pseudomonas mendocina HZ1 and Pseudomonas pseudoalcaligenes WH3 were positively hybridized with both of the probes. Agrobacterium radiobacter HY17, Corynebacterium sp. HY12, YZ and Pseudomonas sp. HY11 had Eco RI fragments hybridized with the K. pneumoniae nifHDKYE ' gene probe. An Eco RI fragment of total DNA from Bacillus megaterium YY4 was positively hybridized to the A. brasilense nifH gene probe. No hybridization sign was found in the total DNA fragments from Alcaligenes cupidus YY6 and Corynebacterium sp. NC11 hybridized with either of the gene probes. The data provide the number and size of EcoRI fragments of the total DNA hybridized with the nif gene probes for these strains of rarely studied species, suggesting additional evidence for N2 fixing and nif gene diversity of N2-fixing bacteria in rice fields along the Yangtze River Plain.

  5. Use of Aeromonas as a process indicator during swine carcass dressing and cutting

    NASA Astrophysics Data System (ADS)

    Palumbo, Samuel A.; Yu, Linda S. L.

    1999-01-01

    Using starch ampicillin agar, qualitative and quantitative determinations of Aeromonas spp. were made at several sites during swine carcass dressing and cutting. Aeromonas spp. were observed at all sites surveyed. Levels increased during shackling and passage through the first and middle polisher/washers, and significantly decreased during the singeing steps. Passage through the final polisher/washer caused a small increase in levels in Aeromonas spp. and these levels then remained constant during the rest of the carcass dressing operation. Aeromonas spp. were also isolated from the room where the carcasses were cut into wholesale cuts and cuts for further processing. Presumptive Aeromonas spp. cultures isolated from the different sites were confirmed as belonging to the genus Aeromonas and then speciated using the biochemical scheme of Joseph and Carnahan; 81% of the cultures were identified at A. hydrophila. Since most isolates were A. hydrophila, determination of the origin of isolates from different sites in the processing plant must await utilizing molecular biotyping techniques on the cultures. These results indicate the Aeromonas spp. occurs extensively in the swine dressing environment and thus represents a possible public health hazard and potential spoilage concern. Changes in cleaning and sanitizing of equipment may be necessary during swine carcass dressing and cutting to guard against this pathogen.

  6. Antibiotic susceptibility of Lactobacillus strains isolated from domestic geese.

    PubMed

    Dec, M; Wernicki, A; Puchalski, A; Urban-Chmiel, R

    2015-01-01

    The aim of this study was to determine the antibiotic susceptibility of 93 Lactobacillus strains isolated from domestic geese raised on Polish farms. The minimal inhibitory concentration (MIC) of 13 antimicrobial substances was determined by the broth microdilution method. All strains were sensitive to the cell wall inhibitors ampicillin and amoxicillin (MIC ≤ 8 μg/ml). Resistance to inhibitors of protein synthesis and to fluoroquinolone inhibitors of replication was found in 44.1% and 60.2% of isolates, respectively; 26.9% strains were resistant to neomycin (MIC ≥ 64 μg/ml), 23.6% to tetracycline (MIC ≥ 32 μg/ml), 15% to lincomycin (MIC ≥ 64 μg/ml), 18.3% to doxycycline (MIC ≥ 32 μg/ml), 9.7% to tylosin (MIC ≥ 32 μg/ml), 56% to flumequine (MIC ≥ 256 μg/ml) and 22.6% to enrofloxacin (MIC ≥ 64 μg/ml). Bimodal distribution of MICs indicative of acquired resistance and unimodal distribution of the high MIC values indicative of intrinsic resistance were correlated with Lactobacillus species. Eleven (11.8%) strains displayed multiple resistance for at least three classes of antibiotics. Data derived from this study can be used as a basis for reviewing current microbiological breakpoints for categorisation of susceptible and resistant strains of Lactobacillus genus and help to assess the hazards associated with the occurrence of drug resistance among natural intestinal microflora. PMID:26105622

  7. Probiotic Properties of Lactobacillus Strains Isolated from Tibetan Kefir Grains

    PubMed Central

    Zheng, Yongchen; Lu, Yingli; Wang, Jinfeng; Yang, Longfei; Pan, Chenyu; Huang, Ying

    2013-01-01

    The objective of this study was to evaluate the functional properties of lactic acid bacteria (LAB) isolated from Tibetan kefir grains. Three Lactobacillus isolates identified as Lactobacillus acidophilus LA15, Lactobacillus plantarum B23 and Lactobacillus kefiri D17 that showed resistance to acid and bile salts were selected for further evaluation of their probiotic properties. The 3 selected strains expressed high in vitro adherence to Caco-2 cells. They were sensitive to gentamicin, erythromycin and chloramphenicol and resistant to vancomycin with MIC values of 26 µg/ml. All 3 strains showed potential bile salt hydrolase (BSH) activity, cholesterol assimilation and cholesterol co-precipitation ability. Additionally, the potential effect of these strains on plasma cholesterol levels was evaluated in Sprague-Dawley (SD) rats. Rats in 4 treatment groups were fed the following experimental diets for 4 weeks: a high-cholesterol diet, a high-cholesterol diet plus LA15, a high-cholesterol diet plus B23 or a high-cholesterol diet plus D17. The total cholesterol, triglyceride and low-density lipoprotein cholesterol levels in the serum were significantly (P<0.05) decreased in the LAB-treated rats compared with rats fed a high-cholesterol diet without LAB supplementation. The high-density lipoprotein cholesterol levels in groups B23 and D17 were significantly (P<0.05) higher than those in the control and LA15 groups. Additionally, both fecal cholesterol and bile acid levels were significantly (P<0.05) increased after LAB administration. Fecal lactobacilli counts were significantly (P<0.05) higher in the LAB treatment groups than in the control groups. Furthermore, the 3 strains were detected in the rat small intestine, colon and feces during the feeding trial. The bacteria levels remained high even after the LAB administration had been stopped for 2 weeks. These results suggest that these strains may be used in the future as probiotic starter cultures for manufacturing

  8. Isolation, identification and antibiotic resistance of Campylobacter strains isolated from domestic and free-living pigeons.

    PubMed

    Dudzic, A; Urban-Chmiel, R; Stępień-Pyśniak, D; Dec, M; Puchalski, A; Wernicki, A

    2016-04-01

    1. The aim of this study was to evaluate the occurrence of Campylobacter spp. in domestic and free-living pigeons and to evaluate the antibiotic resistance profiles. 2. The material consisted of cloacal swabs obtained from 108 homing pigeons and fresh faeces from 72 wild birds from Lublin and its vicinity. The identification of strains isolated on differential/selective media for Campylobacter spp. was carried out by MALDI-TOF and PCR. The susceptibility to antibiotics was evaluated by minimum inhibitory concentration (MIC) in Mueller-Hinton broth. 3. A total of 35 strains of Campylobacter spp. were isolated; 27 were identified as Campylobacter jejuni and 8 as Campylobacter coli. Over half of the isolates were resistant to erythromycin and streptomycin, 40% of strains were resistant to tetracycline and ampicillin and 37% isolates were resistant to amoxicillin. Resistance to two or more antibiotics was observed in all strains tested. 4. The results indicate that both domestic and free-living pigeons are reservoirs for bacteria of the genus Campylobacter, which are characterised by varied and growing resistance to commonly used antibiotics.

  9. Production of N-acyl Homoserine Lactones and Virulence Factors of Waterborne Aeromonas hydrophila.

    PubMed

    Chu, Weihua; Liu, Yongwang; Jiang, Yan; Zhu, Wei; Zhuang, Xiyi

    2013-09-01

    Aeromonads are inhabitants of aquatic ecosystems and are described as being involved in intestinal disturbances and other infections. The purpose of this study was to investigate the production of N-acyl-homoserine lactone (AHL) signal molecules and some virulence factors, including hemolysins, proteases, extracellular nucleases production and cytotoxicity by waterborne Aeromonas hydrophila. A total of 24 strains isolated from fresh-water or diseased fish were used in the study. The majority A.hydrophila strains produce two AHL molecules (21/24), one is N-butanoyl homoserine lactone (BHL), and the other is N-hexanoyl homoserine lactone (HHL) according to thin-layer chromatography analysis. Among the virulence factors tested, more than 83 % of the isolates produced β haemolysin when inoculated on sheep blood agar, only 50 % of the isolates displayed DNase activity, 75 % of the isolates shown proteolytic activity on skimmed milk plate, and cytotoxic activity was detected in 20 of 24 of the isolates. The strains producing AHLs possessed one or more virulence factors. In conclusion, the production of quorum sensing signal molecules is common among the strains that we examined, and there seems to some relationships between quorum sensing signal production and virulence factors in A. hydrophila.

  10. Identification of clinical aeromonas species by rpoB and gyrB sequencing and development of a multiplex PCR method for detection of Aeromonas hydrophila, A. caviae, A. veronii, and A. media.

    PubMed

    Persson, Søren; Al-Shuweli, Suzan; Yapici, Seval; Jensen, Joan N; Olsen, Katharina E P

    2015-02-01

    Conventional identification of Aeromonas species based on biochemical methods is challenged by the heterogeneous nature of the species. Here, we present a new multiplex PCR method directed toward the gyrB and rpoB genes that identifies four Aeromonas species, A. hydrophila, A. media, A. veronii, and A. caviae, and we describe the application of this method on a Danish strain collection.

  11. Antibacterial activity of Lactobacillus strains isolated from dry fermented sausages.

    PubMed

    Vignolo, G M; Suriani, F; Pesce de Ruiz Holgado, A; Oliver, G

    1993-10-01

    One hundred strains of lactic acid bacteria isolated from dry cured sausages were tested for antagonistic activity against a set of test strains. Nine of 52 strains of Lactobacillus casei and three of 48 strains of Lact. plantarun produced inhibition zones against the indicator species. The substance excreted by Lact. casei CRL 705 was active against Lact. plantarum, Listeria monocytogenes, Staphylococcus aureus and a wide range of Gram-negative bacteria. The activity of the antibacterial compound from Lact. casei CRL 705 was destroyed by papain, trypsin and pepsin, but was resistant to heat (100 degrees C for 20 min), lysozyme and catalase. The agent was produced during the growth cycle and when the concentrated and neutralized supernatant fluid was added to a fresh culture of sensitive cells it produced a rapid inactivation. A decrease in optical density (O.D.) over time, indicative of cell lysis, was also observed. These characteristics allowed us to identify the inhibitory compound as a bacteriocin which we termed Lactocin 705. PMID:8226391

  12. Isolation of Omnipotent Suppressors in an [Eta(+)] Yeast Strain

    PubMed Central

    All-Robyn, J. A.; Kelley-Geraghty, D.; Griffin, E.; Brown, N.; Liebman, S. W.

    1990-01-01

    Omnipotent suppressors decrease translational fidelity and cause misreading of nonsense codons. In the presence of the non-Mendelian factor [eta(+)], some alleles of previously isolated omnipotent suppressors are lethal. Thus the current search was conducted in an [eta(+)] strain in an effort to identify new suppressor loci. A new omnipotent suppressor, SUP39, and alleles of sup35, sup45, SUP44 and SUP46 were identified. Efficiencies of the dominant suppressors were dramatically reduced in strains that were cured of non-Mendelian factors by growth on guanidine hydrochloride. Wild-type alleles of SUP44 and SUP46 were cloned and these clones were used to facilitate the genetic analyses. SUP44 was shown to be on chromosome VII linked to cyh2, and SUP46 was clearly identified as distinct from the linked sup45. PMID:2311916

  13. Isolation of an osmotolerant ale strain of Saccharomyces cerevisiae.

    PubMed

    Pironcheva, G

    1998-01-01

    Saccharomyces cerevisiae (ale strain) grown in batch culture to stationary phase was tested for its tolerance to heat (50 degrees C for 5 min), hydrogen peroxide (0.3 M) and salt (growth in 1.5 M sodium chloride/YPD medium). Yeast cells which have been exposed previously to heat shock are more tolerant to hydrogen peroxide and high salt concentrations (1.5 M NaCl) than the controls. Their fermentative activity as judged by glucose consumption and their viability, as judged by cell number and density have higher levels when compared with cells not previously exposed to heat shock. Experimental conditions facilitated the isolation of S. cerevisiae ale strain, which was tolerant to heat, and other agents such as hydrogen peroxide and sodium chloride.

  14. Entamoeba dispar strains: analysis of polymorphism in Tunisian isolates.

    PubMed

    Ayed, Soumaya Ben; Bouratbine, Aida

    2013-01-01

    The ability to detect intra-species polymorphism in Entamoeba histolytica and Entamoeba dispar is an important tool for studying geographic distribution and transmission mechanisms. E. dispar and E. histolytica share the same mechanism for transmission among human hosts, and so after differentiation between these species. We studied the intra-species variation and distribution of E. dispar strains obtained from cyst passers, specifically from African students and Tunisian food handlers. We analyzed the polymorphic region of the chitinase protein gene in 13 individuals infected with E. dispar, of which 9 were from Tunisia and 4 from other African countries. We identified 7 different chitinase patterns in Tunisians while the 4 isolates from other countries each had a distinct pattern. Two of the patterns we found have been reported in studies from Mexico and India, possibly indicating worldwide spread of certain strains.

  15. Cyclic tensile strain upregulates collagen synthesis in isolated tendon fascicles

    SciTech Connect

    Screen, Hazel R.C. . E-mail: H.R.C.Screen@qmul.ac.uk; Shelton, Julia C.; Bader, Dan L.; Lee, David A.

    2005-10-21

    Mechanical stimulation has been implicated as an important regulatory factor in tendon homeostasis. In this study, a custom-designed tensile loading system was used to apply controlled mechanical stimulation to isolated tendon fascicles, in order to examine the effects of 5% cyclic tensile strain at 1 Hz on cell proliferation and matrix synthesis. Sample viability and gross structural composition were maintained over a 24 h loading period. Data demonstrated no statistically significant differences in cell proliferation or glycosaminoglycan production, however, collagen synthesis was upregulated with the application of cyclic tensile strain over the 24 h period. Moreover, a greater proportion of the newly synthesised matrix was retained within the sample after loading. These data provide evidence of altered anabolic activity within tendon in response to mechanical stimuli, and suggest the importance of cyclic tensile loading for the maintenance of the collagen hierarchy within tendon.

  16. The development of a matrix-assisted laser desorption/ionization mass spectrometry-based method for the protein fingerprinting and identification of Aeromonas species using whole cells.

    PubMed

    Donohue, Maura J; Smallwood, Anthony W; Pfaller, Stacy; Rodgers, Mark; Shoemaker, Jody A

    2006-06-01

    This report describes the development of a method to detect the waterborne pathogen Aeromonas using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The genus Aeromonas is one of several medically significant genera that have gained prominence due to their evolving taxonomy and controversial role in human diseases. In this study, MALDI-MS was applied to the characterization of seventeen species of Aeromonas. These seventeen species were represented by thirty-two strains, which included type, reference and clinical isolates. Intact cells from each strain were used to generate a reproducible library of protein mass spectral fingerprints or m/z signatures. Under the test conditions used, peak lists of the mass ions observed in each species revealed that three mass ions were conserved among all the seventeen species tested. These common mass ions having an average m/z of 6301, 12,160 or 12,254, and 13,450, can be potentially used as genus-specific biomarkers to identify Aeromonas in unknown samples. A dendrogram generated using the m/z signatures of all the strains tested indicated that the mass spectral data contained sufficient information to distinguish between genera, species, and strains. There are several advantages of using MALDI-MS based protein mass spectral fingerprinting of whole cells for the identification of microorganisms as well as for their differentiation at the sub-species level: (1) the capability to detect proteins, (2) high throughput, and (3) relatively simple sample preparation techniques. The accuracy and speed with which data can be obtained makes MALDI-MS a powerful tool especially suited for environmental monitoring and detection of biological hazards.

  17. Isolation of a Bacterial Strain Able To Degrade Branched Nonylphenol

    PubMed Central

    Tanghe, Tom; Dhooge, Willem; Verstraete, Willy

    1999-01-01

    Conventional enrichment of microorganisms on branched nonylphenol (NP) as only carbon and energy source yielded mixed cultures able to grow on the organic compound. However, plating yielded no single colonies capable, alone or in combination with other isolates, of degrading the NP in liquid culture. Therefore, a special approach was used, referred to as “serial dilution-plate resuspension,” to reduce culture complexity. In this way, one isolate, TTNP3, tentatively identified as a Sphingomonas sp., was found to be able to grow on NP in liquid culture. Remarkably, this isolate was able to be filtered through a 0.45-μm-pore-diameter filter. Moreover, isolate TTNP3 did not form visible colonies on mineral medium with NP, and it formed visible colonies on R2A agar only after a prolonged incubation of 1 week. High-performance liquid chromatography and gas chromatography-mass spectroscopy analysis of the culture media indicated that the strain starts the degradation of NP with a fission of the phenol ring and preferably uses the para isomer of NP and not the ortho isomer. No distinct accumulation of an intermediary product could be observed. PMID:9925611

  18. Arsenite oxidizing Thiomonas strains isolated from different mining sites

    NASA Astrophysics Data System (ADS)

    Battaglia-Brunet, F.; Duquesne, K.; Dictor, M. C.; Garrido, F.; Bonnefoy, V.; Baranger, P.; Morin, D.

    2003-04-01

    Arsenic is commonly found in sulfide rocks and ores. This toxic metalloid is transferred to the water phase through acidophilic bio-oxidation of sulfides in mining galleries and waste dumps. Inorganic arsenic As(III) and As(V) are both soluble anions, however As(III) is more mobile and toxic than As(V). Bacteria can participate to the biogeochemical arsenic cycling through As(III) oxidation or As(V) reduction. Mineral selective media, containing As(III) as sole energy source, were used to isolate As(III)-oxidizing bacteria from two disused mining sites. Cheni site (Haute Vienne) was a gold mine, and Carnoules (Gard) was lead-zinc mine. Both sites are highly contaminated with arsenic. Samples of sediments and water from Cheni (pH 6) and Carnoules (pH 3) were used to inoculate mineral selective media whose pH were adjusted to those of the sampling environments. In both cases, organisms belonging to the genus Thiomonas were selected, then isolated. These bacteria oxidize arsenite during their exponential growth phase. The Both bacteria are able to grow, as a pure strains, in autotrophic conditions. The As(III)-oxidase activity of the Carnoules strain was exclusively found in cells cultivated with arsenite, and was associated to the membrane. If they can use As(III) as energetic substrate, Thiomonas-related organisms may play an important role in the biogeochemical cycling of arsenic within mining ecosystems.

  19. [Antagonistic properties of Lactobacillus plantarum strains, isolated from traditional fermented products of Ukraine].

    PubMed

    Vasyliuk, O M; Kovalenko, N K; Harmasheva, I L

    2014-01-01

    The antagonistic activity of 109 lactobacillus strains, isolated from traditional fermented products of Ukraine, has been investigated and it has been shown that the significant part of strains show different levels of inhibition of opportunistic and phytopathogenic microorganisms. It has been shown that the antagonistic effect of Lactobacillus plantarum strains on the opportunistic and phytopathogenic microorganisms was dependent on the sources of Lactobacillus strains isolation. L. plantarum strains show a higher level of inhibition against phytopathogenic microorganisms than opportunistic test-strains. Eleven strains of L. plantarum demonstrated antagonistic activity for all used test-strains. PMID:25007440

  20. Gentamicin resistance among Escherichia coli strains isolated in neonatal sepsis.

    PubMed

    Hasvold, J; Bradford, L; Nelson, C; Harrison, C; Attar, M; Stillwell, T

    2013-01-01

    Neonatal sepsis is a significant cause of morbidity and mortality among term and preterm infants. Ampicillin and gentamicin are standard empiric therapy for early onset sepsis. Four cases of neonatal sepsis secondary to Escherichia coli (E. coli) found to be gentamicin resistant occurred within a five week period in one neonatal intensive care unit (NICU). To determine whether these cases could be tied to a single vector of transmission, and to more broadly evaluate the incidence of gentamicin resistant strains of E. coli in the neonatal population at our institution compared to other centers, we reviewed the charts of the four neonates (Infants A through D) and their mothers. The E. coli isolates were sent for Pulse Field Gel Electrophoresis (PFGE) to evaluate for genetic similarity between strains. We also reviewed all positive E. coli cultures from one NICU over a two year period. Infants A and B had genetically indistinguishable strains which matched that of urine and placental cultures of Infant B's mother. Infant C had a genetically distinct organism. Infant D, the identical twin of Infant C, did not have typing performed. Review of all cultures positive for E. coli at our institution showed a 12.9 percent incidence of gentamicin-resistance. A review of other studies showed that rates of resistance vary considerably by institution. We conclude that gentamicin-resistant E. coli is a relatively uncommon cause of neonatal sepsis, but should remain a consideration in patients who deteriorate despite initiation of empiric antibiotics. PMID:24246520

  1. Aeromonas in Arab countries: 1995-2014.

    PubMed

    Ghenghesh, Khalifa Sifaw; Rahouma, Amal; Zorgani, Abdulaziz; Tawil, Khaled; Al Tomi, Abdurazzaq; Franka, Ezzadin

    2015-10-01

    The aim of this review is to provide information on the prevalence, clinical syndromes, and antimicrobial resistance and therapy of Aeromonas spp. infections in Arab countries. The data were obtained by an English language literature search from 1995 to 2014 of Medline and PubMed for papers using the search terms "Aeromonas+name of Arab country (i.e. Algeria, Egypt, etc.)". Additional data were obtained from a Google search using the aforementioned terms. The organisms have been reported from diarrheal children, patients with cholera-like diarrhea, an outbreak of acute gastroenteritis and from different types of animals, foods and water source in several Arab countries in the Middle East and North Africa with predominance of A. hydrophila, A. caviae and A. sobria. Using molecular techniques few studies reported genes encoding several toxins from aeromonads isolated from different sources. Among the antimicrobials examined in the present review third generation cephalosporins, fluoroquinolones and aminoglycosides showed excellent activity and can be employed in the treatment of Aeromonas-associated human infections in Arabic countries. Whenever possible, treatment should be guided by the susceptibility testing results of the isolated organism. In the future, studies employing molecular testing methods are required to provide data on circulating genospecies and their modes of transmission in the community, and on their mechanisms of resistance to antimicrobials. Microbiology laboratories and research centers are encouraged to look for these organisms in clinical, food and water sources to attain a better understanding of the public health risks from these organisms in Arab countries. PMID:26577192

  2. Molecular detection of the Aeromonas virulence aerolysin gene in retail meats from different animal sources in Egypt.

    PubMed

    Osman, Kamelia; Aly, Magdy; Kheader, Afaf; Mabrok, Khaled

    2012-05-01

    Meat commonly contain the same Aeromonas spp. which occur in human diarrhoeal and non-diarrhoeal faecal samples. Motile Aeromonas were isolated from 5.6% of total 302 samples. The distribution of the isolates were 5.9 and 5.2% in fresh and frozen samples, respectively. Of the 302 samples taken of the four animal meat species investigated, the genus Aeromonas were isolated in 12.3% of the fresh samples collected from buffalo meat, in 6.5% of the samples collected from sheep meat and 14.0% from the samples collected from the cattle frozen meat samples. The camel meat did not reveal any Aeromonas isolates. Aeromonas hydrophila was isolated as the most prevalent species with 6.8%, followed by Aeromonas caviae with 2.7% and Aeromonas sobria with 2.1% from the total meat samples. Aerolysin toxin gene (aerA) was detected in 3/17 isolates of A. hydrophila isolated from contaminated meat. Infection due to bacterial pathogen with such virulent factor through contact with contaminated meat while handling them, poses health hazards to humans.

  3. Isolation and genetic characterization of a tembusu virus strain isolated from mosquitoes in Shandong, China.

    PubMed

    Tang, Y; Diao, Y; Chen, H; Ou, Q; Liu, X; Gao, X; Yu, C; Wang, L

    2015-04-01

    Tembusu virus (TMUV) is a flavivirus, presumed to be a mosquito-borne flavivirus of the Ntaya virus subgroup. To date, however, there have been no reports indicating that mosquitoes are involved in the spread of TMUV. In this study, we report the first isolation of TMUV from Culex mosquitoes. We describe the isolation and characterization of a field strain of TMUV from mosquitoes collected in Shandong Province, China. The virus isolate, named TMUV-SDMS, grows well in mosquito cell line C6/36, in Vero and duck embryo fibroblast (DEF) cell lines, and causes significant cytopathic effects in these cell cultures. The TMUV-SDMS genome is a single-stranded RNA, 10 989 nt in length, consisting of a single open reading frame encoding a polyprotein of 3410 amino acids, with 5' and 3' untranslated regions of 142 and 617 nt, respectively. Phylogenetic analysis of the E and NS5 genes revealed that the TMUV-SDMS is closely related to the TMUV YY5 and BYD strains which cause severe egg-drop in ducks. The 3'NTR of TMUV-SDMS contains two pairs of tandem repeat CS and one non-duplicate CS, which have sequence similarities to the same repeats in the YY5 and BYD strains. Our findings indicate that mosquitoes carrying the TMUV may play an important role in the spread of this virus and in disease outbreak. PMID:23711093

  4. Genome sequence of Oceanicaulis sp. strain HTCC2633, isolated from the Western Sargasso Sea.

    PubMed

    Oh, Hyun-Myung; Kang, Ilnam; Vergin, Kevin L; Lee, Kiyoung; Giovannoni, Stephen J; Cho, Jang-Cheon

    2011-01-01

    The genus Oceanicaulis represents dimorphic rods that were originally isolated from a marine dinoflagellate. Here, we announce the genome sequence of Oceanicaulis sp. strain HTCC2633, isolated by dilution-to-extinction culturing from the Sargasso Sea. The genome information of strain HTCC2633 indicates a chemoorganotrophic way of life of this strain.

  5. Draft Genome Sequences of Two Aspergillus fumigatus Strains, Isolated from the International Space Station.

    PubMed

    Singh, Nitin Kumar; Blachowicz, Adriana; Checinska, Aleksandra; Wang, Clay; Venkateswaran, Kasthuri

    2016-01-01

    Draft genome sequences of Aspergillus fumigatus strains (ISSFT-021 and IF1SW-F4), opportunistic pathogens isolated from the International Space Station (ISS), were assembled to facilitate investigations of the nature of the virulence characteristics of the ISS strains to other clinical strains isolated on Earth. PMID:27417828

  6. Genome sequence of Oceanicaulis sp. strain HTCC2633, isolated from the Western Sargasso Sea.

    PubMed

    Oh, Hyun-Myung; Kang, Ilnam; Vergin, Kevin L; Lee, Kiyoung; Giovannoni, Stephen J; Cho, Jang-Cheon

    2011-01-01

    The genus Oceanicaulis represents dimorphic rods that were originally isolated from a marine dinoflagellate. Here, we announce the genome sequence of Oceanicaulis sp. strain HTCC2633, isolated by dilution-to-extinction culturing from the Sargasso Sea. The genome information of strain HTCC2633 indicates a chemoorganotrophic way of life of this strain. PMID:21036991

  7. Draft Genome Sequences of Two Aspergillus fumigatus Strains, Isolated from the International Space Station.

    PubMed

    Singh, Nitin Kumar; Blachowicz, Adriana; Checinska, Aleksandra; Wang, Clay; Venkateswaran, Kasthuri

    2016-07-14

    Draft genome sequences of Aspergillus fumigatus strains (ISSFT-021 and IF1SW-F4), opportunistic pathogens isolated from the International Space Station (ISS), were assembled to facilitate investigations of the nature of the virulence characteristics of the ISS strains to other clinical strains isolated on Earth.

  8. Draft Genome Sequences of Two Aspergillus fumigatus Strains, Isolated from the International Space Station

    PubMed Central

    Singh, Nitin Kumar; Blachowicz, Adriana; Checinska, Aleksandra; Wang, Clay

    2016-01-01

    Draft genome sequences of Aspergillus fumigatus strains (ISSFT-021 and IF1SW-F4), opportunistic pathogens isolated from the International Space Station (ISS), were assembled to facilitate investigations of the nature of the virulence characteristics of the ISS strains to other clinical strains isolated on Earth. PMID:27417828

  9. Characterization of filamentous fungi isolated from Moroccan olive and olive cake: toxinogenic potential of Aspergillus strains.

    PubMed

    Roussos, Sevastianos; Zaouia, Nabila; Salih, Ghislane; Tantaoui-Elaraki, Abdelrhafour; Lamrani, Khadija; Cheheb, Mostafa; Hassouni, Hicham; Verhé, Fréderic; Perraud-Gaime, Isabelle; Augur, Christopher; Ismaili-Alaoui, Mustapha

    2006-05-01

    During the 2003 and 2004 olive oil production campaigns in Morocco, 136 samples from spoiled olive and olive cake were analyzed and 285 strains were isolated in pure culture. Strains included 167 mesophilic strains belonging to ten genera: Penicillium, Aspergillus, Geotrichum, Mucor, Rhizopus, Trichoderma, Alternaria, Acremonium, Humicola, Ulocladium as well as 118 thermophilic strains isolated in 2003 and 2004, mainly belonging to six species: Aspergillus fumigatus, Paecilomyces variotii, Mucor pusillus, Thermomyces lanuginosus, Humicola grisea, and Thermoascus aurantiacus. Penicillium and Aspergillus, respectively, 32.3 and 26.9% of total isolates represented the majority of mesophilic fungi isolated. When considering total strains (including thermotolerant strains) Aspergillus were the predominant strains isolated; follow-up studies on mycotoxins therefore focused primarily on aflatoxins (AFs) and ochratoxin A (OTA) from the latter strains. All isolated Aspergillus flavus strains (9) and Aspergillus niger strains (36) were studied in order to evaluate their capacity to produce AFs and OTA, respectively, when grown on starch-based culture media. Seven of the nine tested A. flavus strains isolated from olive and olive cake produced AF B1 at concentrations between 48 and 95 microg/kg of dry rice weight. As for the A. niger strains, 27 of the 36 strains produced OTA.

  10. Different distribution patterns of ten virulence genes in Legionella reference strains and strains isolated from environmental water and patients.

    PubMed

    Zhan, Xiao-Yong; Hu, Chao-Hui; Zhu, Qing-Yi

    2016-04-01

    Virulence genes are distinct regions of DNA which are present in the genome of pathogenic bacteria and absent in nonpathogenic strains of the same or related species. Virulence genes are frequently associated with bacterial pathogenicity in genus Legionella. In the present study, an assay was performed to detect ten virulence genes, including iraA, iraB, lvrA, lvrB, lvhD, cpxR, cpxA, dotA, icmC and icmD in different pathogenicity islands of 47 Legionella reference strains, 235 environmental strains isolated from water, and 4 clinical strains isolated from the lung tissue of pneumonia patients. The distribution frequencies of these genes in reference or/and environmental L. pneumophila strains were much higher than those in reference non-L. pneumophila or/and environmental non-L. pneumophila strains, respectively. L. pneumophila clinical strains also maintained higher frequencies of these genes compared to four other types of Legionella strains. Distribution frequencies of these genes in reference L. pneumophila strains were similar to those in environmental L. pneumophila strains. In contrast, environmental non-L. pneumophila maintained higher frequencies of these genes compared to those found in reference non-L. pneumophila strains. This study illustrates the association of virulence genes with Legionella pathogenicity and reveals the possible virulence evolution of non-L. pneumophia strains isolated from environmental water.

  11. Occurrence of Aeromonas hydrophila in wild birds.

    PubMed

    Glunder, G; Siegmann, O

    1989-10-01

    Aeromonas hydrophila was isolated from 135 of a total of 1226 wild birds. It was the only bacterial species in eight birds, while other bacteria, mainly enterobacteriaceae, staphylococci and/or streptococci were identified in all other birds. The rate of isolation from aquatic birds (18.5%) was higher (P<0.001) than from birds of terrestrial habitats (3.4%). Infection may also depend on dietary habits: 7.0% of the granivorous and herbivorous species, 8.4% of the omnivores and 12.0% of carnivorous and insectivorous birds were infected. A. hydrophila was isolated more frequently during the summer (12.9%) than the winter (8.9%).

  12. The First Vancomycin-Intermediate Staphylococcus aureus Strains Isolated from Patients in Thailand▿

    PubMed Central

    Lulitanond, Aroonlug; Engchanil, Chulapan; Chaimanee, Prajuab; Vorachit, Malai; Ito, Teruyo; Hiramatsu, Keiichi

    2009-01-01

    We screened 533 and 361 methicillin (meticillin)-resistant Staphylococcus aureus strains isolated in a university hospital in 2002 and 2003 and in 2006 and 2007, respectively, and identified 4 (0.8%) of the strains in the first group and 8 (2.2%) of the strains in second group as heterogeneous vancomycin-resistant S. aureus (heterogeneous VISA) strains and 3 (0.8%) of the strains in the second group as VISA strains. This is the first report of VISA strains isolated from patients in Thailand. PMID:19403764

  13. Advanced Strain-Isolation-Pad Material with Bonded Fibrous Construction

    NASA Technical Reports Server (NTRS)

    Seibold, R. W.; Saito, C. A.; Buller, B. W.

    1982-01-01

    The feasibility of utilizing air lay and liquid lay felt deposition techniques to fabricate strain isolation pad (SIP) materials for the Space Shuttle Orbiter was demonstrated. These materials were developed as candidate replacements for the present needled felt SIP used between the ceramic tiles and the aluminum skin on the undersurface of the Orbiter. The SIP materials that were developed consisted of high temperature aramid fibers deposited by controlled fluid (air or liquid) carriers to form low density unbonded felts. The deposited felts were then bonded at the fiber intersections with a small amount of high temperature polyimide resin. This type of bonded felt construction can potentially eliminate two of the problems associated with the present SIP, viz., transmittal of localized stresses into the tiles and load history dependent mechanical response. However, further work is needed to achieve adequate through thickness tensile strength in the bonded felts.

  14. High frequency of coinfecting enteropathogens in Aeromonas-associated diarrhea of hospitalized Peruvian infants.

    PubMed

    Pazzaglia, G; Sack, R B; Salazar, E; Yi, A; Chea, E; Leon-Barua, R; Guerrero, C E; Palomino, J

    1991-06-01

    Rectal swabs from 391 infants less than 18 months of age who were hospitalized with acute diarrhea and from 138 similarly aged healthy infants were examined for the etiologic agents of diarrhea. Aeromonas spp. were recovered from 205 of 391 (52.4%) diarrheic patients, whereas they were recovered from 12 of 138 (8.7%) controls (P less than 10(-11). Among the 205 Aeromonas-positive diarrheic patients, 118 (57.6%) were found to be coinfected with other common enteropathogens. Of the 164 Aeromonas-positive initial diarrheic specimens, 82 (50.0%) had one or more other enteropathogens present; 30 patients were coinfected with rotavirus, 20 with enterotoxigenic Escherichia coli, 16 with Campylobacter spp., 14 with Shigella spp., 13 with enteropathogenic E. coli, 4 with Vibrio spp., 1 with Salmonella spp., and 1 with Plesiomonas spp. of Aeromonas strains from cases compared with that from controls supports an etiologic role for this organism. However, frequent concomitant infections with other well-recognized enteropathogens and a lack of disease correlation with common Aeromonas phenotypes suggest that only a subset of Aeromonas strains may be diarrhea causing and that such strains may be common to several of the existing species.

  15. Patient isolates of Borrelia burgdorferi sensu lato with genotypic and phenotypic similarities of strain 25015.

    PubMed

    Picken, R N; Cheng, Y; Strle, F; Picken, M M

    1996-11-01

    Strain 25015 is an atypical tick isolate that belongs to a distinct genomic group (DN127) within the general taxon Borrelia burgdorferi sensu lato. Similarities between this strain and a white-footed mouse isolate from Illinois, strain CT39, have been reported. In the course of isolating B. burgdorferi sensu lato in culture from Slovenian patients, 9 isolates were identified with the same genetic profiles as strains 25015 and CT39, as evidenced by restriction enzyme MluI digestion patterns of genomic DNA. The aim of the present study was to molecularly characterize all 11 isolates to examine the extent of their genotypic and phenotypic similarity. The results of molecular studies suggest a close relationship between the patient isolates and strains 25015 and CT39. However, CT39 and several patient isolates possessed unique characteristics that reflect their discrete ontogeny. PMID:8896519

  16. Prevalence and transmission of antimicrobial resistance among Aeromonas populations from a duckweed aquaculture based hospital sewage water recycling system in Bangladesh.

    PubMed

    Rahman, Mokhlasur; Huys, Geert; Kühn, Inger; Rahman, Motiur; Möllby, Roland

    2009-10-01

    In order to investigate the influence of a duckweed aquaculture based hospital sewage water recycling plant on the prevalence and dissemination of antibiotic resistance, we made use of an existing collection of 1,315 Aeromonas isolates that were previously typed by the biochemical fingerprinting PhP-AE system. In these treatment plant, hospital raw sewage water is first collected in a settlement pond (referred to as sewage water in this study) and is then transferred to a lagoon, where the duckweed (Lemnaceae) is grown (referred to as lagoon). The duckweed is harvested and used as feed for the fish in a separate pond (referred to as fish pond). From this collection, representatives of 288 PhP types were subjected to antibiotic susceptibility testing for eight antimicrobials by broth microdilution method. The overall resistance rates among Aeromonas isolates from the treatment plant were highest for ampicillin (87%) and erythromycin (79%) followed by cephalothin (58%), nalidixic acid (52%), streptomycin (51%), tetracycline (31%), chloramphenicol (13%) and gentamicin (8%). A significantly lower prevalence of antibiotic resistance was found in Aeromonas from environmental control water, patient stool samples, duckweed and fish compared to sewage water isolates. The prevalence of resistance in the sewage water was not significantly reduced compared to the lagoon water and fish pond. Throughout the treatment system, the frequencies of resistant strains were found to diminish during the sewage water purification process, i.e. in the lagoon where sewage water is used to grow the duckweed. However, the frequency of resistant strains again increased in the fish pond where sewage grown duckweed is used for aquaculture. Among the selected isolates, two multiresistant clonal groups of Aeromonas caviae HG4 were identified that exhibited indistinguishable PhP and amplified fragment length polymorphism fingerprints and shared a common plasmid of approximately 5 kb

  17. Prevalence and transmission of antimicrobial resistance among Aeromonas populations from a duckweed aquaculture based hospital sewage water recycling system in Bangladesh.

    PubMed

    Rahman, Mokhlasur; Huys, Geert; Kühn, Inger; Rahman, Motiur; Möllby, Roland

    2009-10-01

    In order to investigate the influence of a duckweed aquaculture based hospital sewage water recycling plant on the prevalence and dissemination of antibiotic resistance, we made use of an existing collection of 1,315 Aeromonas isolates that were previously typed by the biochemical fingerprinting PhP-AE system. In these treatment plant, hospital raw sewage water is first collected in a settlement pond (referred to as sewage water in this study) and is then transferred to a lagoon, where the duckweed (Lemnaceae) is grown (referred to as lagoon). The duckweed is harvested and used as feed for the fish in a separate pond (referred to as fish pond). From this collection, representatives of 288 PhP types were subjected to antibiotic susceptibility testing for eight antimicrobials by broth microdilution method. The overall resistance rates among Aeromonas isolates from the treatment plant were highest for ampicillin (87%) and erythromycin (79%) followed by cephalothin (58%), nalidixic acid (52%), streptomycin (51%), tetracycline (31%), chloramphenicol (13%) and gentamicin (8%). A significantly lower prevalence of antibiotic resistance was found in Aeromonas from environmental control water, patient stool samples, duckweed and fish compared to sewage water isolates. The prevalence of resistance in the sewage water was not significantly reduced compared to the lagoon water and fish pond. Throughout the treatment system, the frequencies of resistant strains were found to diminish during the sewage water purification process, i.e. in the lagoon where sewage water is used to grow the duckweed. However, the frequency of resistant strains again increased in the fish pond where sewage grown duckweed is used for aquaculture. Among the selected isolates, two multiresistant clonal groups of Aeromonas caviae HG4 were identified that exhibited indistinguishable PhP and amplified fragment length polymorphism fingerprints and shared a common plasmid of approximately 5 kb

  18. Phenotypic and genotypic characterization of Vagococcus fluvialis, including strains isolated from human sources.

    PubMed Central

    Teixeira, L M; Carvalho, M G; Merquior, V L; Steigerwalt, A G; Brenner, D J; Facklam, R R

    1997-01-01

    This study presents phenotypic and genotypic data for seven isolates of Vagococcus fluvialis, including four strains recovered from human clinical sources, one strain isolated from an environmental source, and two strains isolated from pigs. On the basis of phenotypic characteristics, most isolates were initially classified as "unidentified enterococci," because they resembled atypical arginine-negative enterococcal species. All seven strains as well as the type strain of V. fluvialis reacted with the AccuProbe Enterococcus genetic probe. The seven isolates had virtually indistinguishable whole-cell protein profiles that were similar to that of the V. fluvialis type strain and distinct from those of Enterococcus and Lactococcus species. DNA-DNA reassociation experiments confirmed that the strains were V. fluvialis. They were 71% or more related to the V. fluvialis type strain under optimum and stringent conditions, with 2.5% or less divergence within related sequences. All strains were susceptible to ampicillin, cefotaxime, trimethoprim-sulfamethoxazole, and vancomycin and were resistant to clindamycin, lomefloxacin, and ofloxacin. Strain-to-strain variation was observed in relation to susceptibilities to 18 other antimicrobial agents. Chromosomal DNA was analyzed by pulsed-field gel electrophoresis (PFGE) after digestion with SmaI. Distinctive PFGE patterns were generated, suggesting the nonclonal nature of V. fluvialis strains. Although the number of strains was small, this report provides molecular characterization of V. fluvialis and the first evidence of a possible connection of this species with human infections. PMID:9350732

  19. Aeromonas hydrophila septic arthritis.

    PubMed

    Danaher, Patrick J; Mueller, William P

    2011-12-01

    Septic arthritis is a serious, life and limb threatening infection. If suspected, empiric treatment must begin immediately and account for the most likely pathogens. Eight days following left knee arthroscopic surgery, a 51-year-old active duty male spent approximately 1 hour driving a personal watercraft on Okaloosa Bay near the Gulf of Mexico. Eight days later, he presented to the emergency room with septic arthritis of that knee. Fluid aspirated from the joint yielded Aeromonas hydrophila. The infection resolved with surgical drainage and 21 days of levofloxacin. A. hydrophila is a rare cause of septic arthritis, and reported cases have involved exposure to water after trauma to the affected joint. Many U.S. military bases are located in coastal areas and military members frequently participate in activities which compromise skin integrity and place them at increased risk for contracting waterborne infections. We present the ninth case of A. hydrophila septic arthritis described in the English language literature, highlight the importance of considering this pathogen in at-risk populations, and review the diagnosis and management of septic arthritis.

  20. Molecular Mechanism of Nicotine Degradation by a Newly Isolated Strain, Ochrobactrum sp. Strain SJY1

    PubMed Central

    Yu, Hao; Zhu, Xiongyu; Li, Yangyang

    2014-01-01

    A newly isolated strain, SJY1, identified as Ochrobactrum sp., utilizes nicotine as a sole source of carbon, nitrogen, and energy. Strain SJY1 could efficiently degrade nicotine via a variant of the pyridine and pyrrolidine pathways (the VPP pathway), which highlights bacterial metabolic diversity in relation to nicotine degradation. A 97-kbp DNA fragment containing six nicotine degradation-related genes was obtained by gap closing from the genome sequence of strain SJY1. Three genes, designated vppB, vppD, and vppE, in the VPP pathway were cloned and heterologously expressed, and the related proteins were characterized. The vppB gene encodes a flavin-containing amine oxidase converting 6-hydroxynicotine to 6-hydroxy-N-methylmyosmine. Although VppB specifically catalyzes the dehydrogenation of 6-hydroxynicotine rather than nicotine, it shares higher amino acid sequence identity with nicotine oxidase (38%) from the pyrrolidine pathway than with its isoenzyme (6-hydroxy-l-nicotine oxidase, 24%) from the pyridine pathway. The vppD gene encodes an NADH-dependent flavin-containing monooxygenase, which catalyzes the hydroxylation of 6-hydroxy-3-succinoylpyridine to 2,5-dihydroxypyridine. VppD shows 62% amino acid sequence identity with the hydroxylase (HspB) from Pseudomonas putida strain S16, whereas the specific activity of VppD is ∼10-fold higher than that of HspB. VppE is responsible for the transformation of 2,5-dihydroxypyridine. Sequence alignment and phylogenetic analysis suggested that the VPP pathway, which evolved independently from nicotinic acid degradation, might have a closer relationship with the pyrrolidine pathway. The proteins and functional pathway identified here provide a sound basis for future studies aimed at a better understanding of molecular principles of nicotine degradation. PMID:25344232

  1. Molecular mechanism of nicotine degradation by a newly isolated strain, Ochrobactrum sp. strain SJY1.

    PubMed

    Yu, Hao; Tang, Hongzhi; Zhu, Xiongyu; Li, Yangyang; Xu, Ping

    2015-01-01

    A newly isolated strain, SJY1, identified as Ochrobactrum sp., utilizes nicotine as a sole source of carbon, nitrogen, and energy. Strain SJY1 could efficiently degrade nicotine via a variant of the pyridine and pyrrolidine pathways (the VPP pathway), which highlights bacterial metabolic diversity in relation to nicotine degradation. A 97-kbp DNA fragment containing six nicotine degradation-related genes was obtained by gap closing from the genome sequence of strain SJY1. Three genes, designated vppB, vppD, and vppE, in the VPP pathway were cloned and heterologously expressed, and the related proteins were characterized. The vppB gene encodes a flavin-containing amine oxidase converting 6-hydroxynicotine to 6-hydroxy-N-methylmyosmine. Although VppB specifically catalyzes the dehydrogenation of 6-hydroxynicotine rather than nicotine, it shares higher amino acid sequence identity with nicotine oxidase (38%) from the pyrrolidine pathway than with its isoenzyme (6-hydroxy-l-nicotine oxidase, 24%) from the pyridine pathway. The vppD gene encodes an NADH-dependent flavin-containing monooxygenase, which catalyzes the hydroxylation of 6-hydroxy-3-succinoylpyridine to 2,5-dihydroxypyridine. VppD shows 62% amino acid sequence identity with the hydroxylase (HspB) from Pseudomonas putida strain S16, whereas the specific activity of VppD is ∼10-fold higher than that of HspB. VppE is responsible for the transformation of 2,5-dihydroxypyridine. Sequence alignment and phylogenetic analysis suggested that the VPP pathway, which evolved independently from nicotinic acid degradation, might have a closer relationship with the pyrrolidine pathway. The proteins and functional pathway identified here provide a sound basis for future studies aimed at a better understanding of molecular principles of nicotine degradation. PMID:25344232

  2. Molecular mechanism of nicotine degradation by a newly isolated strain, Ochrobactrum sp. strain SJY1.

    PubMed

    Yu, Hao; Tang, Hongzhi; Zhu, Xiongyu; Li, Yangyang; Xu, Ping

    2015-01-01

    A newly isolated strain, SJY1, identified as Ochrobactrum sp., utilizes nicotine as a sole source of carbon, nitrogen, and energy. Strain SJY1 could efficiently degrade nicotine via a variant of the pyridine and pyrrolidine pathways (the VPP pathway), which highlights bacterial metabolic diversity in relation to nicotine degradation. A 97-kbp DNA fragment containing six nicotine degradation-related genes was obtained by gap closing from the genome sequence of strain SJY1. Three genes, designated vppB, vppD, and vppE, in the VPP pathway were cloned and heterologously expressed, and the related proteins were characterized. The vppB gene encodes a flavin-containing amine oxidase converting 6-hydroxynicotine to 6-hydroxy-N-methylmyosmine. Although VppB specifically catalyzes the dehydrogenation of 6-hydroxynicotine rather than nicotine, it shares higher amino acid sequence identity with nicotine oxidase (38%) from the pyrrolidine pathway than with its isoenzyme (6-hydroxy-l-nicotine oxidase, 24%) from the pyridine pathway. The vppD gene encodes an NADH-dependent flavin-containing monooxygenase, which catalyzes the hydroxylation of 6-hydroxy-3-succinoylpyridine to 2,5-dihydroxypyridine. VppD shows 62% amino acid sequence identity with the hydroxylase (HspB) from Pseudomonas putida strain S16, whereas the specific activity of VppD is ∼10-fold higher than that of HspB. VppE is responsible for the transformation of 2,5-dihydroxypyridine. Sequence alignment and phylogenetic analysis suggested that the VPP pathway, which evolved independently from nicotinic acid degradation, might have a closer relationship with the pyrrolidine pathway. The proteins and functional pathway identified here provide a sound basis for future studies aimed at a better understanding of molecular principles of nicotine degradation.

  3. Decolorization of textile azo dye and Congo red by an isolated strain of the dissimilatory manganese-reducing bacterium Shewanella xiamenensis BC01.

    PubMed

    Ng, I-Son; Chen, Tingting; Lin, Rong; Zhang, Xia; Ni, Chao; Sun, Dongzhe

    2014-03-01

    Shewanella xiamenensis BC01 (SXM) was isolated from sediment collected off Xiamen, China and was identified based on the phylogenetic tree of 16S rRNA sequences and the gyrB gene. This strain showed high activity in the decolorization of textile azo dyes, especially methyl orange, reactive red 198, and recalcitrant dye Congo red, decolorizing at rates of 96.2, 93.0, and 87.5%, respectively. SXM had the best performance for the specific decolorization rate (SDR) of azo dyes compared to Proteus hauseri ZMd44 and Aeromonas hydrophila NIU01 strains and had an SDR similar to Shewanella oneidensis MR-1 in Congo red decolorization. Luria-Bertani medium was the optimal culture medium for SXM, as it reached a density of 4.69 g-DCW L(-1) at 16 h. A mediator (manganese) significantly enhanced the biodegradation and flocculation of Congo red. Further analysis with UV-VIS, Fourier Transform Infrared spectroscopy, and Gas chromatography-mass spectrometry demonstrated that Congo red was cleaved at the azo bond, producing 4,4'-diamino-1,1'-biphenyl and 1,2'-diamino naphthalene 4-sulfonic acid. Finally, SEM results revealed that nanowires exist between the bacteria, indicating that SXM degradation of the azo dyes was coupled with electron transfer through the nanowires. The purpose of this work is to explore the utilization of a novel, dissimilatory manganese-reducing bacterium in the treatment of wastewater containing azo dyes.

  4. Malate dehydrogenase: a useful phylogenetic marker for the genus Aeromonas.

    PubMed

    Farfán, Maribel; Miñana-Galbis, David; Garreta, Albert; Lorén, J Gaspar; Fusté, M Carmen

    2010-12-01

    The reconstruction of correct genealogies among biological entities, the estimation of the divergence time between organisms or the study of the different events that occur along evolutionary lineages are not always based on suitable genes. For reliable results, it is necessary to look at full-length sequences of genes under stabilizing selection (neutral or purifying) and behaving as good molecular clocks. In bacteria it has been proved that the malate dehydrogenase gene (mdh) can be used to determine the inter- and intraspecies divergence, and hence this gene constitutes a potential marker for phylogeny and bacterial population genetics. We have sequenced the full-length mdh gene in 36 type and reference strains of Aeromonas. The species grouping obtained in the phylogenetic tree derived from mdh sequences was in agreement with that currently accepted for the genus Aeromonas. The maximum likelihood models applied to our sequences indicated that the mdh gene is highly conserved among the Aeromonas species and the main evolutionary force acting on it is purifying selection. Only two sites under potential diversifying selection were identified (T 108 and S 193). In order to determine if these two residues could have an influence on the MDH structure, we mapped them in a three-dimensional model constructed from the sequence of A. hydrophila using the human mitochondrial MDH as a template. The presence of purifying selection together with the linear relationship between substitutions and gene divergence makes the mdh an excellent candidate gene for a phylogeny of Aeromonas and probably for other bacterial groups.

  5. Selective enrichment media bias the types of Salmonella enterica strains isolated from mixed strain cultures and complex enrichment broths.

    PubMed

    Gorski, Lisa

    2012-01-01

    For foodborne outbreak investigations it can be difficult to isolate the relevant strain from food and/or environmental sources. If the sample is contaminated by more than one strain of the pathogen the relevant strain might be missed. In this study mixed cultures of Salmonella enterica were grown in one set of standard enrichment media to see if culture bias patterns emerged. Nineteen strains representing four serogroups and ten serotypes were compared in four-strain mixtures in Salmonella-only and in cattle fecal culture enrichment backgrounds using Salmonella enrichment media. One or more strain(s) emerged as dominant in each mixture. No serotype was most fit, but strains of serogroups C2 and E were more likely to dominate enrichment culture mixtures than strains of serogroups B or C1. Different versions of Rappaport-Vassiliadis (RV) medium gave different patterns of strain dominance in both Salmonella-only and fecal enrichment culture backgrounds. The fittest strains belonged to serogroups C1, C2, and E, and included strains of S. Infantis, S. Thompson S. Newport, S. 6,8:d:-, and S. Give. Strains of serogroup B, which included serotypes often seen in outbreaks such as S. Typhimurium, S. Saintpaul, and S. Schwarzengrund were less likely to emerge as dominant strains in the mixtures when using standard RV as part of the enrichment. Using a more nutrient-rich version of RV as part of the protocol led to a different pattern of strains emerging, however some were still present in very low numbers in the resulting population. These results indicate that outbreak investigations of food and/or other environmental samples should include multiple enrichment protocols to ensure isolation of target strains of Salmonella.

  6. Clinical Implications of Species Identification in Monomicrobial Aeromonas Bacteremia

    PubMed Central

    Wu, Chi-Jung; Chen, Po-Lin; Hsueh, Po-Ren; Chang, Ming-Chung; Tsai, Pei-Jane; Shih, Hsin-I; Wang, Hsuan-Chen; Chou, Pei-Hsin; Ko, Wen-Chien

    2015-01-01

    Background Advances in Aeromonas taxonomy have led to the reclassification of aeromonads. Hereon, we aimed to re-evaluate the characteristics of Aeromonas bacteremia, including those of a novel species, Aeromonas dhakensis. Methodology/Principal Findings A retrospective study of monomicrobial Aeromonas bacteremia at a medical center in southern Taiwan from 2004–2011 was conducted. Species identification was based on rpoB sequencing. Of bacteremia of 153 eligible patients, A. veronii (50 isolates, 32.7%), A. dhakensis (48, 31.4%), A. caviae (43, 28.1%), and A. hydrophila (10, 6.5%) were the principal causative species. A. dhakensis and A. veronii bacteremia were mainly community-acquired and presented as primary bacteremia, spontaneous bacterial peritonitis, or skin and soft-tissue infection, whereas A. caviae was associated with hospital-onset bacteremia. The distribution of the AmpC β-lactamase and metallo-β-lactamase genes was species-specific: blaAQU-1, blaMOX, or blaCepH was present in A. dhakensis, A. caviae, or A. hydrophila, respectively, and blaCphA was present in A. veronii, A. dhakensis, and A. hydrophila. The cefotaxime resistance rates of the A. caviae, A. dhakensis, and A. hydrophila isolates were higher than that of A. veronii (39.5%%, 25.0%, and 30% vs. 2%, respectively). A. dhakensis bacteremia was linked to the highest 14-day sepsis-related mortality rate, followed by A. hydrophila, A. veronii, and A. caviae bacteremia (25.5%, 22.2%, 14.0%, and 4.7%, respectively; P = 0.048). Multivariate analysis revealed that A. dhakensis bacteremia, active malignancies, and a Pitt bacteremia score ≥ 4 was an independent mortality risk factor. Conclusions/Significance Characteristics of Aeromonas bacteremia vary between species. A. dhakensis prevalence and its associated poor outcomes suggest it an important human pathogen. PMID:25679227

  7. Occurrence, molecular characterization, and antimicrobial susceptibility of Aeromonas spp. in marine species of shrimps cultured at inland low salinity ponds.

    PubMed

    Yano, Yutaka; Hamano, Kaoru; Tsutsui, Isao; Aue-Umneoy, Dusit; Ban, Masatoshi; Satomi, Masataka

    2015-05-01

    We aimed to document the risk of Aeromonas spp. in marine shrimp species cultured in inland low salinity ponds in Thailand. In 14 of 18 shrimp samples retrieved from inland grow-up ponds, Aeromonas spp. were detected at ranges from 4667 to 1,500,000 CFU/g body weight. The phylogenetic tree constructed with the gyrB and cpn60 concatenated sequences indicated that the 87 isolates consisted of Aeromonas veronii (70%), Aeromonas aquariorum (18%), Aeromonas caviae (7%), Aeromonas jandaei (2%), and Aeromonas schubertii (2%). The potential virulence of the isolates was examined by phenotypic and PCR assays. Hemolytic activity and the extracellular activity of lipase, DNase, and gelatinase were observed in most isolates (94-99%). PCR revealed the presence of 9 genes related to virulence in the 87 isolates: act (75%), aer (74%), alt (30%), ast (1%), ascV (34%), aexT (24%), fla (92%), ela (34%), and lip (24%). The susceptibility profiles to 14 antimicrobial agents of isolates were typical for the genus, but resistance to cefotaxime, a third-generation cephalosporin, and imipenem were found in two A. aquariorum and in three A. veronii isolates, respectively. These resistances were confirmed by determining minimum inhibitory concentrations. Our results indicate that the microbiological risk posed by Aeromonas should be considered for marine shrimp species that are cultured in low-salinity ponds. These shrimps may also be a vehicle for the transfer of different genotypes of Aeromonas and antibiotic-resistant determinants to regions worldwide through trade.

  8. Occurrence, molecular characterization, and antimicrobial susceptibility of Aeromonas spp. in marine species of shrimps cultured at inland low salinity ponds.

    PubMed

    Yano, Yutaka; Hamano, Kaoru; Tsutsui, Isao; Aue-Umneoy, Dusit; Ban, Masatoshi; Satomi, Masataka

    2015-05-01

    We aimed to document the risk of Aeromonas spp. in marine shrimp species cultured in inland low salinity ponds in Thailand. In 14 of 18 shrimp samples retrieved from inland grow-up ponds, Aeromonas spp. were detected at ranges from 4667 to 1,500,000 CFU/g body weight. The phylogenetic tree constructed with the gyrB and cpn60 concatenated sequences indicated that the 87 isolates consisted of Aeromonas veronii (70%), Aeromonas aquariorum (18%), Aeromonas caviae (7%), Aeromonas jandaei (2%), and Aeromonas schubertii (2%). The potential virulence of the isolates was examined by phenotypic and PCR assays. Hemolytic activity and the extracellular activity of lipase, DNase, and gelatinase were observed in most isolates (94-99%). PCR revealed the presence of 9 genes related to virulence in the 87 isolates: act (75%), aer (74%), alt (30%), ast (1%), ascV (34%), aexT (24%), fla (92%), ela (34%), and lip (24%). The susceptibility profiles to 14 antimicrobial agents of isolates were typical for the genus, but resistance to cefotaxime, a third-generation cephalosporin, and imipenem were found in two A. aquariorum and in three A. veronii isolates, respectively. These resistances were confirmed by determining minimum inhibitory concentrations. Our results indicate that the microbiological risk posed by Aeromonas should be considered for marine shrimp species that are cultured in low-salinity ponds. These shrimps may also be a vehicle for the transfer of different genotypes of Aeromonas and antibiotic-resistant determinants to regions worldwide through trade. PMID:25583334

  9. Molecular Detection, Quantification, and Toxigenicity Profiling of Aeromonas spp. in Source- and Drinking-Water

    PubMed Central

    Robertson, Boakai K; Harden, Carol; Selvaraju, Suresh B; Pradhan, Suman; Yadav, Jagjit S

    2014-01-01

    Aeromonas is ubiquitous in aquatic environments and has been associated with a number of extra-gastrointestinal and gastrointestinal illnesses. This warrants monitoring of raw and processed water sources for pathogenic and toxigenic species of this human pathogen. In this study, a total of 17 different water samples [9 raw and 8 treated samples including 4 basin water (partial sand filtration) and 4 finished water samples] were screened for Aeromonas using selective culturing and a genus-specific real-time quantitative PCR assay. The selective culturing yielded Aeromonas counts ranging 0 – 2 x 103CFU/ml and 15 Aeromonas isolates from both raw and treated water samples. The qPCR analysis indicated presence of a considerable nonculturable population (3.4 x 101 – 2.4 x 104 cells/ml) of Aeromonas in drinking water samples. Virulence potential of the Aeromonas isolates was assessed by multiplex/singleplex PCR-based profiling of the hemolysin and enterotoxin genes viz cytotoxic heat-labile enterotoxin (act), heat-labile cytotonic enterotoxin (alt), heat-stable cytotonic enterotoxin (ast), and aerolysin (aerA) genes. The water isolates yielded five distinct toxigenicity profiles, viz. act, alt, act+alt, aerA+alt, and aerA+alt+act. The alt gene showed the highest frequency of occurrence (40%), followed by the aerA (20%), act (13%), and ast (0%) genes. Taken together, the study demonstrated the occurrence of a considerable population of nonculturable Aeromonads in water and prevalence of toxigenic Aeromonas spp. potentially pathogenic to humans. This emphasizes the importance of routine monitoring of both source and drinking water for this human pathogen and role of the developed molecular approaches in improving the Aeromonas monitoring scheme for water. PMID:24949108

  10. Molecular Detection, Quantification, and Toxigenicity Profiling of Aeromonas spp. in Source- and Drinking-Water.

    PubMed

    Robertson, Boakai K; Harden, Carol; Selvaraju, Suresh B; Pradhan, Suman; Yadav, Jagjit S

    2014-01-01

    Aeromonas is ubiquitous in aquatic environments and has been associated with a number of extra-gastrointestinal and gastrointestinal illnesses. This warrants monitoring of raw and processed water sources for pathogenic and toxigenic species of this human pathogen. In this study, a total of 17 different water samples [9 raw and 8 treated samples including 4 basin water (partial sand filtration) and 4 finished water samples] were screened for Aeromonas using selective culturing and a genus-specific real-time quantitative PCR assay. The selective culturing yielded Aeromonas counts ranging 0 - 2 x 10(3)CFU/ml and 15 Aeromonas isolates from both raw and treated water samples. The qPCR analysis indicated presence of a considerable nonculturable population (3.4 x 10(1) - 2.4 x 10(4) cells/ml) of Aeromonas in drinking water samples. Virulence potential of the Aeromonas isolates was assessed by multiplex/singleplex PCR-based profiling of the hemolysin and enterotoxin genes viz cytotoxic heat-labile enterotoxin (act), heat-labile cytotonic enterotoxin (alt), heat-stable cytotonic enterotoxin (ast), and aerolysin (aerA) genes. The water isolates yielded five distinct toxigenicity profiles, viz. act, alt, act+alt, aerA+alt, and aerA+alt+act. The alt gene showed the highest frequency of occurrence (40%), followed by the aerA (20%), act (13%), and ast (0%) genes. Taken together, the study demonstrated the occurrence of a considerable population of nonculturable Aeromonads in water and prevalence of toxigenic Aeromonas spp. potentially pathogenic to humans. This emphasizes the importance of routine monitoring of both source and drinking water for this human pathogen and role of the developed molecular approaches in improving the Aeromonas monitoring scheme for water.

  11. Living in an Extremely Polluted Environment: Clues from the Genome of Melanin-Producing Aeromonas salmonicida subsp. pectinolytica 34melT

    PubMed Central

    Pavan, María Elisa; Pavan, Esteban E.; López, Nancy I.; Levin, Laura

    2015-01-01

    Aeromonas salmonicida subsp. pectinolytica 34melT can be considered an extremophile due to the characteristics of the heavily polluted river from which it was isolated. While four subspecies of A. salmonicida are known fish pathogens, 34melT belongs to the only subspecies isolated solely from the environment. Genome analysis revealed a high metabolic versatility, the capability to cope with diverse stress agents, and the lack of several virulence factors found in pathogenic Aeromonas. The most relevant phenotypic characteristics of 34melT are pectin degradation, a distinctive trait of A. salmonicida subsp. pectinolytica, and melanin production. Genes coding for three pectate lyases were detected in a cluster, unique to this microorganism, that contains all genes needed for pectin degradation. Melanin synthesis in 34melT is hypothesized to occur through the homogentisate pathway, as no tyrosinases or laccases were detected and the homogentisate 1,2-dioxygenase gene is inactivated by a transposon insertion, leading to the accumulation of the melanin precursor homogentisate. Comparative genome analysis of other melanogenic Aeromonas strains revealed that this gene was inactivated by transposon insertions or point mutations, indicating that melanin biosynthesis in Aeromonas occurs through the homogentisate pathway. Horizontal gene transfer could have contributed to the adaptation of 34melT to a highly polluted environment, as 13 genomic islands were identified in its genome, some of them containing genes coding for fitness-related traits. Heavy metal resistance genes were also found, along with others associated with oxidative and nitrosative stresses. These characteristics, together with melanin production and the ability to use different substrates, may explain the ability of this microorganism to live in an extremely polluted environment. PMID:26025898

  12. Living in an Extremely Polluted Environment: Clues from the Genome of Melanin-Producing Aeromonas salmonicida subsp. pectinolytica 34melT.

    PubMed

    Pavan, María Elisa; Pavan, Esteban E; López, Nancy I; Levin, Laura; Pettinari, M Julia

    2015-08-01

    Aeromonas salmonicida subsp. pectinolytica 34mel(T) can be considered an extremophile due to the characteristics of the heavily polluted river from which it was isolated. While four subspecies of A. salmonicida are known fish pathogens, 34mel(T) belongs to the only subspecies isolated solely from the environment. Genome analysis revealed a high metabolic versatility, the capability to cope with diverse stress agents, and the lack of several virulence factors found in pathogenic Aeromonas. The most relevant phenotypic characteristics of 34mel(T) are pectin degradation, a distinctive trait of A. salmonicida subsp. pectinolytica, and melanin production. Genes coding for three pectate lyases were detected in a cluster, unique to this microorganism, that contains all genes needed for pectin degradation. Melanin synthesis in 34mel(T) is hypothesized to occur through the homogentisate pathway, as no tyrosinases or laccases were detected and the homogentisate 1,2-dioxygenase gene is inactivated by a transposon insertion, leading to the accumulation of the melanin precursor homogentisate. Comparative genome analysis of other melanogenic Aeromonas strains revealed that this gene was inactivated by transposon insertions or point mutations, indicating that melanin biosynthesis in Aeromonas occurs through the homogentisate pathway. Horizontal gene transfer could have contributed to the adaptation of 34mel(T) to a highly polluted environment, as 13 genomic islands were identified in its genome, some of them containing genes coding for fitness-related traits. Heavy metal resistance genes were also found, along with others associated with oxidative and nitrosative stresses. These characteristics, together with melanin production and the ability to use different substrates, may explain the ability of this microorganism to live in an extremely polluted environment. PMID:26025898

  13. Living in an Extremely Polluted Environment: Clues from the Genome of Melanin-Producing Aeromonas salmonicida subsp. pectinolytica 34melT.

    PubMed

    Pavan, María Elisa; Pavan, Esteban E; López, Nancy I; Levin, Laura; Pettinari, M Julia

    2015-08-01

    Aeromonas salmonicida subsp. pectinolytica 34mel(T) can be considered an extremophile due to the characteristics of the heavily polluted river from which it was isolated. While four subspecies of A. salmonicida are known fish pathogens, 34mel(T) belongs to the only subspecies isolated solely from the environment. Genome analysis revealed a high metabolic versatility, the capability to cope with diverse stress agents, and the lack of several virulence factors found in pathogenic Aeromonas. The most relevant phenotypic characteristics of 34mel(T) are pectin degradation, a distinctive trait of A. salmonicida subsp. pectinolytica, and melanin production. Genes coding for three pectate lyases were detected in a cluster, unique to this microorganism, that contains all genes needed for pectin degradation. Melanin synthesis in 34mel(T) is hypothesized to occur through the homogentisate pathway, as no tyrosinases or laccases were detected and the homogentisate 1,2-dioxygenase gene is inactivated by a transposon insertion, leading to the accumulation of the melanin precursor homogentisate. Comparative genome analysis of other melanogenic Aeromonas strains revealed that this gene was inactivated by transposon insertions or point mutations, indicating that melanin biosynthesis in Aeromonas occurs through the homogentisate pathway. Horizontal gene transfer could have contributed to the adaptation of 34mel(T) to a highly polluted environment, as 13 genomic islands were identified in its genome, some of them containing genes coding for fitness-related traits. Heavy metal resistance genes were also found, along with others associated with oxidative and nitrosative stresses. These characteristics, together with melanin production and the ability to use different substrates, may explain the ability of this microorganism to live in an extremely polluted environment.

  14. Molecular characterization of the Israeli B. bigemina vaccine strain and field isolates.

    PubMed

    Molad, T; Erster, O; Fleiderovitz, L; Roth, A; Leibovitz, B; Wolkomirsky, R; Mazuz, M L; Behar, A; Markovics, A

    2015-09-15

    The present study demonstrated the genetic character of the Israeli Babesia bigemina vaccine strain and field isolates, based on rap-1a and rap-1c gene sequences. The RAP-1a of blood-derived Israeli B. bigemina field isolates shared 100% amino acid sequence identity. However, comparison of RAP-1c from various Israeli B. bigemina field isolates revealed that the total sequence identity among the field isolates ranged from 98.2 to 100%. High identity was observed when RAP-1a sequences from the Israeli vaccine strain and field isolates were compared with RAP-1a from Egypt, Syria, Mexico and South Africa, while, the Israeli RAP-1c sequences showed the highest identity to the Mexican isolate JG-29 and to the PR isolate from Puerto-Rico. Based on sequence variations between the rap-1a of the vaccine strain and that of the field isolate, and between the rap-1c of the vaccine strain and that of the field isolates, nPCR-RFLP procedures were developed that enable, for the first time differentiation between the Israeli B. bigemina vaccine strain and field-infection isolates. These assays could serve as fast and sensitive methods for detection and differentiation between Israeli B. bigemina vaccine strains and field isolates, as well as for epidemiological investigations.

  15. Prevalence and antibiotic resistance of Enterococcus strains isolated from poultry.

    PubMed

    Stępień-Pyśniak, Dagmara; Marek, Agnieszka; Banach, Tomasz; Adaszek, Łukasz; Pyzik, Ewelina; Wilczyński, Jarosław; Winiarczyk, Stanisław

    2016-06-01

    The aim of this study was to evaluate the frequency of occurrence of bacteria of the genus Enterococcus in poultry, to identify them by means of matrixassisted laser desorption/ionisation time-of-flight mass spectrometry (MALDITOF MS), and to analyse the antimicrobial susceptibility of the isolated strains to the drugs most frequently used in poultry. The material for the bacteriological tests was obtained mainly from the heart (97%) of the birds investigated. Of a total of 2,970 samples tested, 911 (30.7%) tested positive for Enterococcus spp. Enterococci were detected in broilers (88.1%), laying hens (5.3%), turkeys (3.9%), breeding hens (2.2%), and geese (0.4%). The most commonly identified species were Enterococcus (E.) faecalis (74.7%), E. faecium (10.1%), E. gallinarum (5.5%), E. hirae (4.6%), and E. cecorum (4.1%). The most frequent resistance properties were resistance to sulphamethoxazole/trimethoprim (88%), tylosin (71.4%), enrofloxacin (69.4%), doxycycline (67.3%), and lincomycin/spectinomycin (56.1%). Only one vancomycin-resistant Enterococcus, E. cecorum from a broiler, was found. PMID:27342087

  16. Prevalence and antibiotic resistance of Enterococcus strains isolated from poultry.

    PubMed

    Stępień-Pyśniak, Dagmara; Marek, Agnieszka; Banach, Tomasz; Adaszek, Łukasz; Pyzik, Ewelina; Wilczyński, Jarosław; Winiarczyk, Stanisław

    2016-06-01

    The aim of this study was to evaluate the frequency of occurrence of bacteria of the genus Enterococcus in poultry, to identify them by means of matrixassisted laser desorption/ionisation time-of-flight mass spectrometry (MALDITOF MS), and to analyse the antimicrobial susceptibility of the isolated strains to the drugs most frequently used in poultry. The material for the bacteriological tests was obtained mainly from the heart (97%) of the birds investigated. Of a total of 2,970 samples tested, 911 (30.7%) tested positive for Enterococcus spp. Enterococci were detected in broilers (88.1%), laying hens (5.3%), turkeys (3.9%), breeding hens (2.2%), and geese (0.4%). The most commonly identified species were Enterococcus (E.) faecalis (74.7%), E. faecium (10.1%), E. gallinarum (5.5%), E. hirae (4.6%), and E. cecorum (4.1%). The most frequent resistance properties were resistance to sulphamethoxazole/trimethoprim (88%), tylosin (71.4%), enrofloxacin (69.4%), doxycycline (67.3%), and lincomycin/spectinomycin (56.1%). Only one vancomycin-resistant Enterococcus, E. cecorum from a broiler, was found.

  17. Phylogenetic Relationships of Xylella fastidiosa Strains Isolated from Landscape Ornamentals in Southern California.

    PubMed

    Hernandez-Martinez, Rufina; de la Cerda, Karla A; Costa, Heather S; Cooksey, Donald A; Wong, Francis P

    2007-07-01

    ABSTRACT Xylella fastidiosa is an insect-borne, xylem-limited pathogenic bacterium that has been associated with a rise in incidence of diseased landscape ornamentals in southern California. The objective of this study was to genetically characterize strains isolated from ornamental hosts to understand their distribution and identity. Strains of X. fastidiosa isolated from ornamentals were characterized using a multiprimer polymerase chain reaction (PCR) system, random amplified polymorphic DNA (RAPD)-PCR, and sequence analysis of the 16S-23S rDNA intergenic spacer region (ISR). Based on RAPD-PCR and 16S-23S rDNA ISR, strains isolated from daylily, jacaranda, and magnolia clustered with members of X. fastidiosa subsp. sandyi and caused oleander leaf scorch but not Pierce's disease symptoms in glasshouse assays on oleander and grape, respectively. This demonstrated both that our groupings based on genetic characterization were valid and that strains of X. fastidiosa subsp. sandyi are present in hosts other than oleander. Strains isolated from Spanish broom, cherry, and one strain isolated from western redbud clustered with X. fastidiosa subsp. fastidiosa members. Strains isolated from purple-leafed plum, olive, peach, plum, sweetgum, maidenhair tree, crape myrtle, and another western redbud strain clustered with members of X. fastidiosa subsp. multiplex. All strains isolated from mulberry and one from heavenly bamboo formed a separate cluster that has not yet been defined as a subspecies. PMID:18943935

  18. Draft Genome of the Multidrug-Resistant Acinetobacter baumannii Strain A155 Clinical Isolate

    PubMed Central

    Arivett, Brock A.; Fiester, Steven E.; Ream, David C.; Centrón, Daniela; Ramírez, Maria S.; Tolmasky, Marcelo E.

    2015-01-01

    Acinetobacter baumannii is a bacterial pathogen with serious implications on human health, due to increasing reports of multidrug-resistant strains isolated from patients. Total DNA from the multidrug-resistant A. baumannii strain A155 clinical isolate was sequenced to greater than 65× coverage, providing high-quality contig assemblies. PMID:25814610

  19. Complete Genome Sequence of Lactobacillus fermentum CECT 5716, a Probiotic Strain Isolated from Human Milk▿

    PubMed Central

    Jiménez, Esther; Langa, Susana; Martín, Virginia; Arroyo, Rebeca; Martín, Rocío; Fernández, Leónides; Rodríguez, Juan M.

    2010-01-01

    Lactobacillus fermentum is a heterofermentative lactic acid bacterium and is frequently isolated from mucosal surfaces of healthy humans. Lactobacillus fermentum CECT 5716 is a well-characterized probiotic strain isolated from human milk and, at present, is used in commercial infant formulas. Here, we report the complete and annotated genome sequence of this strain. PMID:20639335

  20. Whole-genome sequencing of Salmonella enterica subsp. enterica serovar Cubana strains isolated from agricultural sources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report draft genomes of Salmonella enterica subsp. enterica Serovar Cubana strain CVM42234 isolated from chick feed in 2012 and Salmonella Cubana strain 76814 isolated from swine in 2004. The genome sizes are 4,975,046 and 4,936,251 base pairs, respectively....

  1. Detection of Aeromonas hydrophila in a drinking-water distribution system: a field and pilot study.

    PubMed

    Chauret, C; Volk, C; Creason, R; Jarosh, J; Robinson, J; Warnes, C

    2001-08-01

    A 16-month study was conducted on the presence of Aeromonas hydrophila in drinking water in Indiana, U.S.A. Enumeration was conducted in source water, in various sites within a water treatment plant, and in the distribution system in both bulk water and biofilm, as well as in a simulated (annular reactors) drinking-water distribution system. Presumptive Aeromonas spp. counts on source waters regularly approached 10(3)-10(4) CFU/100 mL, during summer months and granular activated carbon - filtered water counts ranged from <1 to 490 CFU/100 mL. In source water, presumptive Aeromonas levels were related to water temperature. Aeromonas hydrophila was never detected in the treatment plant effluent or distributed bulk water, showing disinfectant efficiency on suspended bacteria; however, isolates of A. hydrophila were identified in 7.7% of the biofilm samples, indicating a potential for regrowth and contamination of drinking-water distribution systems.

  2. Isolation of a Variant Strain of Pleurotus eryngii and the Development of Specific DNA Markers to Identify the Variant Strain.

    PubMed

    Lee, Hyun-Jun; Kim, Sang-Woo; Ryu, Jae-San; Lee, Chang-Yun; Ro, Hyeon-Su

    2014-03-01

    A degenerated strain of Pleurotus eryngii KNR2312 was isolated from a commercial farm. Random amplified polymorphic DNA analysis performed on the genomic DNA of the normal and degenerated strains of this species revealed differences in the DNA banding pattern. A unique DNA fragment (1.7 kbp), which appeared only in the degenerated strain, was isolated and sequenced. Comparing this sequence with the KNR2312 genomic sequence showed that the sequence of the degenerated strain comprised three DNA regions that originated from nine distinct scaffolds of the genomic sequence, suggesting that chromosome-level changes had occurred in the degenerated strain. Using the unique sequence, three sets of PCR primers were designed that targeted the full length, the 5' half, and the 3' half of the DNA. The primer sets P2-1 and P2-2 yielded 1.76 and 0.97 kbp PCR products, respectively, only in the case of the degenerated strain, whereas P2-3 generated a 0.8 kbp product in both the normal and the degenerated strains because its target region was intact in the normal strain as well. In the case of the P2-1 and P2-2 sets, the priming regions of the forward and reverse primers were located at distinct genomic scaffolds in the normal strain. These two primer sets specifically detected the degenerate strain of KNR2312 isolated from various mushrooms including 10 different strains of P. eryngii, four strains of P. ostreatus, and 11 other wild mushrooms. PMID:24808734

  3. [Protein fingerprinting as a method for strain-specific differentiation of technologically useful Lactobacillus strains from clinical isolates].

    PubMed

    Klein, G; Hack, B; Zimmermann, K; Reuter, G

    1994-09-01

    Lactobacilli are often used in products of animal origin because of their technological properties and as protective cultures against pathogenic microorganisms, however they are supposed to be related to human infections as well. Therefore 39 strains of species that are in biotechnological usage, including the type strains, and some clinical isolates were investigated. 9 strains of L. acidophilus, 7 of L. gasseri and 23 strains of L. rhamnosus were tested. Biochemical and physiological properties were proved by classical tests. Analysis of the total soluble cytoplasmatic protein patterns was performed with diamine silver staining, a technique not previously applied to lactobacilli. Classical tests were able to confirm all strains as belonging to one of the three species. Analysis of protein patterns allowed to differentiate between strains of the same species. In case of L. acidophilus biotechnologically used strains and clinical isolates were clustered separately. L. rhamnosus formed three clusters. SDS-PAGE of proteins together with diamine silver staining seems to be helpful to detect intra-species differences. It was stated, that technologically used strains of lactobacilli could clearly be differentiated from another and also from clinical isolates.

  4. O serogroups, biotypes, and eae genes in Escherichia coli strains isolated from diarrheic and healthy rabbits.

    PubMed Central

    Blanco, J E; Blanco, M; Blanco, J; Mora, A; Balaguer, L; Mouriño, M; Juarez, A; Jansen, W H

    1996-01-01

    A total of 305 Escherichia coli strains isolated from diarrheic and healthy rabbits in 10 industrial fattening farms from different areas of Spain were serotyped, biotyped, and tested for the presence of the eae gene and toxin production. The characteristics found in strains isolated from healthy rabbits were generally different from those observed in E. coli strains associated with disease. Thus, strains with the eae gene (74% versus 22%); strains belonging to serogroups O26, O49, O92, O103, and O128 (64% versus 12%); rhamnose-negative strains (51% versus 5%); and rhamnose-negative O103 strains with eae genes present (41% versus 1%) were significantly (P < 0.001 in all cases) more frequently detected in isolates from diarrheic animals than in those from healthy rabbits. Whereas a total of 35 serogroups and 17 biotypes were distinguished, the majority of the strains obtained from diarrheic rabbits belonged to only four serobiotypes, which in order of frequency were O103:B14 (72 strains), O103:B6 (16 strains), O26:B13 (12 strains), and O128:B30 (12 strains). These four serobiotypes accounted for 48% (112 of 231) and 5% (4 of 74) of the E. coli strains isolated from diarrheic and healthy rabbits, respectively. Only six strains were toxigenic (three CNF1+, two CNF2+, and one VT1+). We conclude that enteropathogenic E. coli strains that possess the eae gene are a common cause of diarrhea in Spanish rabbit farms and that the rhamnose-negative highly pathogenic strains of serotype O103:K-:H2 and biotype B14 are especially predominant. Detection of the eae gene is a useful method for the identification of enteropathogenic E. coli strains from rabbits. However, a combination of serogrouping and biotyping may be sufficient to accurately identify the highly pathogenic strains for rabbits. PMID:8940455

  5. Complete Genome Sequence of Lactococcus lactis subsp. lactis A12, a Strain Isolated from Wheat Sourdough.

    PubMed

    Guellerin, Maéva; Passerini, Delphine; Fontagné-Faucher, Catherine; Robert, Hervé; Gabriel, Valérie; Loux, Valentin; Klopp, Christophe; Le Loir, Yves; Coddeville, Michèle; Daveran-Mingot, Marie-Line; Ritzenthaler, Paul; Le Bourgeois, Pascal

    2016-01-01

    We report here the complete genome sequence of Lactococcus lactis subsp. lactis strain A12, a strain isolated from sourdough. The circular chromosome and the four plasmids reveal genes involved in carbohydrate metabolism that are potentially required for the persistence of this strain in such a complex ecosystem. PMID:27634985

  6. Biofilm production and resistance to disinfectants in Salmonella strains isolated from prickly pear, water, and soil.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to: i) determine the capacity of Salmonella isolated from prickly pear (10 strains), water samples (2 strains), and soil (3 strains) to form biofilms, and ii) evaluate the bactericidal effect of citric acid, lactic acid, and sodium hypochlorite on biofilm-forming st...

  7. Complete Genome Sequence of Lactococcus lactis subsp. lactis A12, a Strain Isolated from Wheat Sourdough

    PubMed Central

    Guellerin, Maéva; Passerini, Delphine; Fontagné-Faucher, Catherine; Robert, Hervé; Gabriel, Valérie; Loux, Valentin; Klopp, Christophe; Le Loir, Yves; Coddeville, Michèle; Daveran-Mingot, Marie-Line; Ritzenthaler, Paul

    2016-01-01

    We report here the complete genome sequence of Lactococcus lactis subsp. lactis strain A12, a strain isolated from sourdough. The circular chromosome and the four plasmids reveal genes involved in carbohydrate metabolism that are potentially required for the persistence of this strain in such a complex ecosystem. PMID:27634985

  8. Genome Sequence of Gluconacetobacter sp. Strain SXCC-1, Isolated from Chinese Vinegar Fermentation Starter▿

    PubMed Central

    Du, Xin-jun; Jia, Shi-ru; Yang, Yue; Wang, Shuo

    2011-01-01

    Gluconacetobacter strains are prominent bacteria during traditional vinegar fermentation. Here, we report a draft genome sequence of Gluconacetobacter sp. strain SXCC-1. This strain was isolated from a fermentation starter (Daqu) used for commercial production of Shanxi vinegar, the best-known vinegar of China. PMID:21551293

  9. Complete genome sequence of Brucella melitensis biovar 3 strain NI, isolated from an aborted bovine fetus.

    PubMed

    Liu, Wenxiao; Jing, Zhigang; Ou, Qixing; Cui, Buyun; He, Yongqun; Wu, Qingmin

    2012-11-01

    From an aborted bovine fetus in China, a bacterial strain named NI was isolated and identified as Brucella melitensis by a PCR assay. Strain NI was further characterized as B. melitensis biovar 3 using biochemical assays. Here we report the complete genome sequence of strain NI.

  10. Genome Sequences of Brucella abortus and Brucella suis Strains Isolated from Bovine in Zimbabwe

    PubMed Central

    Ledwaba, Betty; Mafofo, Joseph

    2014-01-01

    This is a report of whole-genome sequences of a Brucella abortus strain and two Brucella suis strains isolated from bovine in Zimbabwe. These strains were selected based on their origin and data obtained when using multiplex PCR assays, then sequenced using next-generation sequencing technologies. PMID:25342680

  11. Complete Genome Sequence of Aurantimicrobium minutum Type Strain KNCT, a Planktonic Ultramicrobacterium Isolated from River Water.

    PubMed

    Nakai, Ryosuke; Fujisawa, Takatomo; Nakamura, Yasukazu; Nishide, Hiroyo; Uchiyama, Ikuo; Baba, Tomoya; Toyoda, Atsushi; Fujiyama, Asao; Naganuma, Takeshi; Niki, Hironori

    2016-01-01

    Aurantimicrobium minutum type strain KNC(T) is a planktonic ultramicrobacterium isolated from river water in western Japan. Strain KNC(T) has an extremely small, streamlined genome of 1,622,386 bp comprising 1,575 protein-coding sequences. The genome annotation suggests that strain KNC(T) has an actinorhodopsin-based photometabolism. PMID:27365350

  12. Draft Genome Sequence of Rheinheimera sp. Strain SA_1 Isolated from Iron Backwash Sludge in Germany.

    PubMed

    Schröder, Josephin; Braun, Burga; Liere, Karsten; Szewzyk, Ulrich

    2016-01-01

    Rheinheimera sp. strain SA_1 is an iron-depositing bacterium for which we report a draft genome sequence. Strain SA_1 was isolated from iron backwash sludge of a waterworks in Germany. The Illumina MiSeq technique was used to sequence the genome of the strain. PMID:27540074

  13. Complete Genome Sequence of Lactococcus lactis subsp. lactis A12, a Strain Isolated from Wheat Sourdough.

    PubMed

    Guellerin, Maéva; Passerini, Delphine; Fontagné-Faucher, Catherine; Robert, Hervé; Gabriel, Valérie; Loux, Valentin; Klopp, Christophe; Le Loir, Yves; Coddeville, Michèle; Daveran-Mingot, Marie-Line; Ritzenthaler, Paul; Le Bourgeois, Pascal

    2016-09-15

    We report here the complete genome sequence of Lactococcus lactis subsp. lactis strain A12, a strain isolated from sourdough. The circular chromosome and the four plasmids reveal genes involved in carbohydrate metabolism that are potentially required for the persistence of this strain in such a complex ecosystem.

  14. Draft Genome Sequence of Rheinheimera sp. Strain SA_1 Isolated from Iron Backwash Sludge in Germany

    PubMed Central

    Schröder, Josephin; Liere, Karsten; Szewzyk, Ulrich

    2016-01-01

    Rheinheimera sp. strain SA_1 is an iron-depositing bacterium for which we report a draft genome sequence. Strain SA_1 was isolated from iron backwash sludge of a waterworks in Germany. The Illumina MiSeq technique was used to sequence the genome of the strain. PMID:27540074

  15. Genome sequences of two pseudoalteromonas strains isolated from the South china sea.

    PubMed

    Zeng, Zhenshun; Dai, Shikun; Xie, Yunchang; Tian, Xinpeng; Li, Jie; Wang, Xiaoxue

    2014-01-01

    Two Pseudoalteromonas strains, SCSIO 04301 and SCSIO 11900, were isolated from the South China Sea, and both strains form biofilms. Here we present the draft genome sequences of these two strains, which will aid the study of marine microbes that are adapted to marine sediments or are associated with eukaryotic hosts.

  16. [Plague in Algeria: about five strains of Yersinia pestis isolated during the outbreak of June 2003].

    PubMed

    Lounici, M; Lazri, M; Rahal, K

    2005-02-01

    In this study, we isolated and identified five strains of Yersinia pestis during an epidemic occurred in west of Algeria in June 2003. The bacteriological identification was confirmed by bacteriophage susceptibility. All these strains belonged to the biovar Orientalis (they did not ferment glycerol but did reduce nitrate to nitrite) which caused the current pandemic. The in vitro activities of antimicrobial agents used to treat plague and recommended for prophylaxis, showed that they are active against all strains. The comparison of these strains by plasmid profile analyse demonstrated that all isolates had three plasmids: 110, 70 and 9.5 kb, which are present in Y. pestis strains.

  17. Distribution of uropathogenic virulence factors among Escherichia coli strains isolated from dogs and cats.

    PubMed

    Yuri, K; Nakata, K; Katae, H; Yamamoto, S; Hasegawa, A

    1998-03-01

    A variety of virulence factors (VFs) such as type 1 fimbriae, pilus associated with pyelonephritis, S fimbriae, afimbrial adhesin, alpha-hemolysin, aerobactin and cytotoxic necrotizing factor 1 are associated with uropathogenic Escherichia coli. In this study, 80 uropathogenic E. coli strains in 50 dogs and 30 cats suffering from UTI. In addition, 60 E. coli strains were isolated from fecal samples from 30 each of healthy dogs and cats. The distribution of VFs of uropathogenic E. coli strains isolated from dogs and cats suffering from urinary tract infections (UTI) were examined by the colony hybridization test with seven DNA probes specific for VFs, and the results were compared with those obtained in the studies on strains from humans with UTI. In uropathogenic E. coli strains isolated from dogs and cats suffering from UTI, VFs were detected as frequently as in the strains isolated from humans with UTI. Although less frequently, genes encoding these VFs especially pap, sfa, hly, and cnf 1 genes were also associated with E. coli strains isolated from feces of healthy cats, in contrast to the distribution pattern of uropathogenic E. coli observed in humans. Furthermore, all VFs except pil were significantly more frequently detected in strains isolated from urine of animals with cystitis than in those isolated from feces of healthy humans. These results indicate that VFs of E. coli contribute to the pathogenesis of UTI in dogs and cats.

  18. Pathogenic properties of Escherichia coli strains isolated from diarrheic commercial rabbits.

    PubMed Central

    Peeters, J E; Pohl, P; Okerman, L; Devriese, L A

    1984-01-01

    Thirty-two different strains of Escherichia coli isolated from diarrheic commercial rabbits showing intestinal attachment of bacilli were studied. None of the strains produced thermostable or thermolabile enterotoxins, and none was invasive. Strains isolated from suckling rabbits attached in vitro to the brush borders of intestinal villi, whereas strains from weanling rabbits did not. After experimental infection of 5-week-old rabbits, the 26 strains isolated from weaned diarrheic rabbits attached to the epithelium of ileum, cecum, and colon, whereas only slight attachment was found after infection with the six strains isolated from suckling diarrheic rabbits. The former strains induced diarrhea in 87% of the rabbits, whereas the latter induced diarrhea in only 9% of inoculated rabbits. E. coli isolated from healthy rabbits did not cause diarrhea. Strains isolated from diarrheic suckling rabbits all belonged to serotype O109:K-:H2, whereas strains from diarrheic weaned rabbits belonged to at least eight different serogroups. It is suggested that two different mechanisms of E. coli enteropathy might exist in rabbits. PMID:6378965

  19. Identification and biochemical characterization of Leishmania strains isolated in Peru, Mexico, and Spain.

    PubMed

    Rodríguez-González, Isabel; Marín, Clotilde; Vargas, Franklin; Córdova, Ofelia; Barrera, Mario; Gutiérrez-Sánchez, Ramón; Alunda, Jose María; Sánchez-Moreno, Manuel

    2006-01-01

    Eight Leishmania promastigotes were isolated from different geographical areas: three (LP1, LP2, and LP3) from the provincial department La Libertad and the fourth (LP4) from the department of Cajamarca (northern Peru); another three (LM1, LM2, and LM3) in the province of Campeche (Mexico); and the last (LS1) from a clinical case of a dog in Madrid (Spain). The isolates were characterized by carbohydrate cell-surface residues using agglutinations with four purified lectins, by isoenzyme analysis using different isoenzymes, by analysis of kinetoplast DNA (kDNA) restriction fragment length polymorphism using four different restriction endonucleases and by the final metabolite patterns after in vitro culture. These isolates were compared with four reference strains and typified as: Leishmania (Leishmania) donovani, two strains of L. (L.) infantum, and one species of L. (Viania) peruviana. According to our results and the statistical study, the Peruvian isolates represent three different strains: one would be L. (V.) peruviana, another the strain isolated in Cajamarca (LP4) and the third would include the three strains from the department of La Libertad (LP1, LP2, and LP3), these latter three isolates being phylogenetically closer to the reference strain L. (L.) donovani. Meanwhile, the three isolates from Mexico form a group with close phylogenetic relationships to each other. The isolate from Spain belongs to the species L. (L.) infantum. Thus, a close correlation was drawn between the identity of each strain and its geographical origin.

  20. Human influenza A viruses isolated in South America: genetic relations, adamantane resistance and vaccine strain match.

    PubMed

    Goñi, Natalia; Russi, José; Cristina, Juan

    2009-03-01

    In order to gain insight into the genetic relations among H3N2 Influenza A virus (IAV) circulating in the South American region from 1999 to 2007, to investigate the presence of adamantane-resistant strains in this region, and to establish the genetic relations among that strains and vaccine strains recommended for the Southern hemisphere, 11 haemagglutinin (HA) H3 IAV sequences obtained from Uruguayan patients were aligned with corresponding sequences from 68 H3 IAV strains isolated in South America and 9 H3 IAV vaccine strains. Maximum likelihood phylogenetic tree analysis was performed using the GTR evolutionary model. The results of these studies indicate that multiple clades co-circulate during most influenza seasons in South America. Strikingly, one strain isolated in Uruguay in 2005 and all strains isolated in that country during the 2007 season bear an HA adamantane-resistant polymorphism. No other strain isolated in South America previous to the 2005 season bears that HA characteristic amino acid change. Only vaccine strains recommended for the 2007 season were assigned to the same cluster with all available IAV isolated in South America for that season. Evolution of IAV in this region appears to be shaped by re-introduction of new strains.

  1. Thiamethoxam degradation by Pseudomonas and Bacillus strains isolated from agricultural soils.

    PubMed

    Rana, Shivnam; Jindal, Vikas; Mandal, Kousik; Kaur, Gurpreet; Gupta, V K

    2015-05-01

    Twelve bacterial species were evaluated to know the degradation pattern of thiamethoxam in liquid medium. All the bacterial species could actively degrade phorate in a mineral salt medium containing phorate (50 μg ml(-1)) as sole carbon source. As these species have ability to degrade, we used these for the degradation of thiamethoxam--a neonicoitinoids. Screening of 12 active phorate-metabolizing bacterial species resulted in selection of Bacillus aeromonas strain IMBL 4.1 and Pseudomonas putida strain IMBL 5.2 causing 45.28 and 38.23 % thiamethoxam (50 μg ml(-1)) reduction, respectively, in 15 days as potential thiamethoxam degrading species. These two bacterial species grew optimally at 37 °C under shake culture conditions in MSMT medium raised with initial pH of 6.0-6.5 and use of these optimum cultural conditions resulted in improved thiamethoxam degradation by these bacterial species. These species caused maximum thiamethoxam degradation only in the presence of thiamethoxam as sole source of carbon and energy and the same was reduced in the presence of easily metabolize able carbon (C₀ and C₁) and nitrogen ((N₀, N₁ and N₂) sources. This could be attributed to involvement of repressible metabolic pathways, reactions of which are inhibited by the presence of easily available nutrients for growth. Besides above, qualitative analysis of thiamethoxam residues by gas liquid chromatography revealed complete metabolization of thiamethoxam without detectable accumulation of any known thiamethoxam metabolites. PMID:25917187

  2. DNA-DNA reassociation and phenotypic data indicate synonymy between Aeromonas enteropelogenes Schubert et al. 1990 and Aeromonas trota Carnahan et al. 1991.

    PubMed

    Huys, Geert; Denys, Rik; Swings, Jean

    2002-11-01

    Mainly on the basis of phylogenetic and genotypic evidence, it has been suggested previously that the species Aeromonas enteropelogenes Schubert et al. 1990 is identical to the species Aeromonas trota Carnahan et al. 1991. Probably because the description of A. enteropelogenes preceded the proposal of A. trota by only a few months, DNA-DNA hybridizations were never performed between representative strains of these two taxa. In the present study, new DNA-DNA hybridizations between the type strain of A. enteropelogenes, LMG 12646(T) (= DSM 6394(T)), and reference strains of A. trota, including its type strain LMG 12223(T)(= ATCC 49657(T)), showed a genomic relatedness of 81-99%. In addition, phenotypic characterization revealed that the two type strains exhibited identical API 20E and API 50CHE biochemical profiles and were both susceptible to ampicillin and carbenicillin. Collectively, our new DNA reassociation and phenotypic data confirm previous taxonomic data that indicate that the taxa A. enteropelogenes and A. trota are synonymous members of the same Aeromonas species. Although the species name A. enteropelogenes has nomenclatural priority, the authors would like to discourage the use of this name because the name A. trota has been cited much more frequently. The preferential use of A. trota in future publications may be the best option to avoid ambiguity in the description of ampicillinsusceptible aeromonads and to secure nomenclatural continuity in Aeromonas literature.

  3. Polymorphism of Beauveria bassiana (Deuteromycota: Hyphomycetes) strains isolated from Ixodes ricinus (Acari: Ixodidae) in Moldova.

    PubMed

    Mitina, G V; Tokarev, Y S; Movila, A A; Yli-Mattila, T

    2011-03-01

    Polymorphism of 10 Beauveria bassiana strains, isolated from Ixodes ricinus in Moldova, was evaluated using traditional (morphological and cultural properties) and molecular (RAPD patterns and ITS sequences) methods. The isolates differed greatly in morphological and cultural features, such as color, consistence, and growth rate. Four RAPD-PCR markers were used to evaluate genetic diversity of the strains. Phylogenetic neighbor-joining analysis of RAPD patterns divided strains into 3 major clades. The ITS sequences of 8 strains were identical to those of known B. bassiana strains. Two subsets (1 and 2) different by one nucleotide change were found in the ITS1 region. One strain of subset 1 was different from known B. bassiana strains by possessing 2 point mutations in the ITS region. RAPD-based clustering correlated to ITS sequence and colony morphology-based grouping of the strains.

  4. Enterotoxin production, phage typing and serotyping of Staphylococcus aureus strains isolated from clinical materials and food.

    PubMed Central

    Melconian, A. K.; Brun, Y.; Fleurette, J.

    1983-01-01

    The production of enterotoxins A, B, C and F by strains of Staphylococcus aureus isolated from various clinical sources and from isolates implicated in food poisoning was investigated. One hundred and ninety one of the 374 clinical strains (51.1%) were found to be enterotoxigenic; of these, 81 (27.7%) strains produced enterotoxin A, 57 (15.3%) strains produced enterotoxin B, 23 (6.2%) strains produced enterotoxin C, and 64 (17.1%) strains produced enterotoxin F. These enterotoxigenic strains were most frequently lysed by phages of group III (21.5%) or were not typable (22%). Eighteen of the 29 strains implicated in food poisoning were enterotoxigenic. The correlation of antigens and bacteriophage patterns with enterotoxigenicity was determined: enterotoxin A being related to a4 antigen, enterotoxin B to phages of 94/96 complex with c1, o antigens, and enterotoxin F to phages of group I with 2632, k1k2, m antigens. PMID:6227656

  5. Molecular characterization of Acidithiobacillus ferrooxidans and A. thiooxidans strains isolated from mine wastes in Brazil.

    PubMed

    Paulino, L C; Bergamo, R F; Garcia, O; de Mello, M P; Manfio, G P; Ottoboni, L M

    2001-10-01

    Nineteen strains of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans, including 12 strains isolated from coal, copper, gold and uranium mines in Brazil, strains isolated from similar sources in other countries and the type strains of the two species were characterized together with the type strain of A. caldus by using a combination of molecular systematic methods, namely ribotyping, BOX- and ERIC-PCR and DNA-DNA hybridization assays. Data derived from the molecular fingerprinting analyses showed that the tested strains encompassed a high degree of genetic variability. Two of the Brazilian A. ferrooxidans organisms (strains SSP and PCE) isolated from acid coal mine waste and uranium mine effluent, respectively, and A. thiooxidans strain DAMS, isolated from uranium mine effluent, were the most genetically divergent organisms. The DNA-DNA hybridization data did not support the allocation of Acidithiobacillus strain SSP to the A. ferrooxidans genomic species, as it shared only just over 40% DNA relatedness with the type strain of the species. Acidithiobacillus strain SSP was not clearly related to A. ferrooxidans in the 16S rDNA tree.

  6. Full-Genome Sequences of Seven Fatal Enterovirus 71 Strains Isolated in Shenzhen, China, in 2014.

    PubMed

    Chen, Long; He, Ya-Qing; Meng, Jun; Xiong, Ling-Hong; Wang, Chao; Yao, Xiang-Jie; Zhang, Hai-Long; Zhang, Ren-Li; Yang, Hong

    2016-01-01

    The whole-genome sequences of seven fatal enterovirus 71 (EV71) strains, isolated in southern China, in 2014, were determined. The complete genome sequences of these strains displayed close relationships to native EV71 strains and showed 94.2% to 99.8% identity to each other. All of these strains were assigned to subgenotype C4a based on phylogenetic analysis of the VP1 gene. PMID:27125487

  7. Full-Genome Sequences of Seven Fatal Enterovirus 71 Strains Isolated in Shenzhen, China, in 2014

    PubMed Central

    He, Ya-Qing; Meng, Jun; Xiong, Ling-Hong; Wang, Chao; Yao, Xiang-Jie; Zhang, Hai-Long; Zhang, Ren-Li

    2016-01-01

    The whole-genome sequences of seven fatal enterovirus 71 (EV71) strains, isolated in southern China, in 2014, were determined. The complete genome sequences of these strains displayed close relationships to native EV71 strains and showed 94.2% to 99.8% identity to each other. All of these strains were assigned to subgenotype C4a based on phylogenetic analysis of the VP1 gene. PMID:27125487

  8. Molecular characterization of Yersinia strains isolated from human and environmental sources.

    PubMed

    Marranzano, M; Agodi, A; Gulisano, M

    1993-01-01

    Thirty-seven strains of Yersinia isolated from human and environmental sources were investigated for virulence and molecular characteristics. Clinical isolates of Y. enterocolitica serotypes 0:3 and 0:9, harbouring the 45 MDa virulence plasmid were Ca++ dependent and responded positively to the CV-binding assay. The environmental Y. kristensenii strain, although harbouring a 45 MDa plasmid proved to be negative for both assays. All the environmental strains showed pyrazinamidase activity, while isolates from human sources proved negative. Two different plasmid profiles were disclosed: one Y. enterocolitica strain (serotype 0:7, 8) showed one plasmid of 67 MDa and one plasmid of 1.5 MDa. Eleven human isolates of Y. enterocolitica and one environmental strain of Y. krinstensenii showed only one plasmid of 45 MDa. Restriction endonuclease analysis of the 45 MDa plasmids supported the hypothesis that the environmental Y. krinstensenii plasmid is unrelated to the family of homologous virulence plasmids of Y. enterocolitica.

  9. [Aeromonas spp asociated to acute diarrheic disease in Cuba: case-control study].

    PubMed

    Bravo, Laura; Fernández, Anabel; Núñez, Fidel Á; Rivero, Luis A; Ramírez, Margarita; Aguila, Adalberto; Ledo, Yudith; Cruz, Yanaika; Hernández, Jenny

    2012-02-01

    The members of the genus Aeromonas are currently considered important gastrointestinal pathogens in different geographical areas. From February 1985 to January 2005 several case-control studies were coordinated by the National Reference Laboratory for Diarrheal Diseases from the Pedro Kouri Institute. The study purpose was to analyze a possible pathogenic role for Aeromonas spp in Cuban children with acute diarrhea. In that period 2,322 children less than 5 years old with acute diarrhea were studied for diarhoeal pathogens and another group of 2,072 non hospitalized children without diarrhea during the similar time from the same geographical areas and matched by ages were recruited. In the group of children with diarrheas (cases), Aeromonas spp. was isolated in 166 (7.15%) and in the control group the microorganism was found in only 35 (1.76%). When Aeromonas isolation rates were compared between both groups, we found that probability to isolate this specie was significantly higher in cases than in controls (OR = 4.48, 95% IC: 3.05-6.60; P < 0.001). The Aeromonas species more frequently isolated were A. caviae, A. hydrophila, and A. veronii bv sobria. Other enteric pathogens detected in children with diarrhea were: Shigella spp in 418 (18%) (P < 0.0001), Salmonella spp in 53 (2.3%) (P < 0.01), and enteropathogenic E. coli in 58 (2.49%) (P < 0.05).

  10. Phylogenetic diversity of Aeromonas from "alheira," a traditional Portuguese meat product.

    PubMed

    Fontes, M C; Martins, C; Martínez-Murcia, A J; Saavedra, M J

    2012-08-01

    "Alheira" is a traditional smoked meat sausage produced in the north of Portugal, representing an important economic resource for the region. This meat product has been subjected to research studies with the aim of detecting the presence of common foodborne pathogens, but, to our knowledge, isolation of emerging foodborne Aeromonas from alheira has never been previously described. Present work attempts to evaluate the Aeromonas species diversity of 84 isolates of Aeromonas spp. collected from 32 alheira samples. All presumptive Aeromonas isolates were subjected to genotyping by enterobacterial repetitive intergenic consensus-polymerase chain reaction analysis. The isolates presenting a different pattern were subjected to gyrB gene sequencing for species classification, and the species A. hydrophila, A. salmonicida, A. caviae, A. media, and A. allosaccharophila were identified. The Aeromonas species diversity found has not been previously described in any other meat product evaluated in previous studies. It is also important to highlight the presence of A. hydrophila and A. caviae because they were previously associated with illness in humans, including gastroenteritis.

  11. [Susceptibility to antibiotics and biochemical activity of strains of Acinetobacter sp. isolated from various sources].

    PubMed

    Gospodarek, E

    1993-01-01

    The study was performed on 576 Acinetobacter strains isolated from clinical material, objects from hospital, environment, soil, water and from animals. Applying API 20NE system identification was following: A. baumanii (61.1%), A. junii (19.4%), A. haemolyticus (4.3%), A. lwoffii (3.3%), A. johnsonii (0.52%) and not belonging to above genus strains (11.3%). Over 47% strains of Acinetobacter were isolated from clinical material as the only bacteria (mainly from samples received from intensive care units and surgical and urological wards). Out of 23 antibiotics and antimicrobials used for investigation of 535 strains of Acinetobacter, most active were imipenem (99%) of susceptible strains, ofloxacin and ciprofloxacin (95%) and netilmicin (88%). Multiple resistant strains were isolated more frequently from hospital environment than from other sources--these were mostly A. baumanii and A. junii. PMID:8189806

  12. Novel Chlamydiales strains isolated from a water treatment plant.

    PubMed

    Corsaro, Daniele; Feroldi, Veronica; Saucedo, Gemma; Ribas, Ferran; Loret, Jean-François; Greub, Gilbert

    2009-01-01

    Chlamydiae are obligate intracellular bacteria infecting free-living amoebae, vertebrates and some invertebrates. Novel members are regularly discovered, and there is accumulating evidence supporting a very important diversity of chlamydiae in the environment. In this study, we investigated the presence of chlamydiae in a drinking water treatment plant. Samples were used to inoculate Acanthamoeba monolayers (Acanthamoeba co-culture), and to recover autochthonous amoebae onto non-nutritive agar. Chlamydiae were searched for by a pan-chlamydia 16S rRNA gene PCR from both Acanthamoeba co-cultures and autochthonous amoebae, and phylotypes determined by 16S rRNA gene sequencing. Autochthonous amoebae also were identified by 18S rRNA gene amplification and sequencing. From a total of 79 samples, we recovered eight chlamydial strains by Acanthamoeba co-culture, but only one of 28 amoebae harboured a chlamydia. Sequencing results and phylogenetic analysis showed our strains belonging to four distinct chlamydial lineages. Four strains, including the strain recovered within its natural host, belonged to the Parachlamydiaceae; two closely related strains belonged to the Criblamydiaceae; two distinct strains clustered with Rhabdochlamydia spp.; one strain clustered only with uncultured environmental clones. Our results confirmed the usefulness of amoeba co-culture to recover novel chlamydial strains from complex samples and demonstrated the huge diversity of chlamydiae in the environment, by identifying several new species including one representing the first strain of a new family.

  13. Evaluating virulence of waterborne and clinical Aeromonas isolates using gene expression and mortality in neonatal mice followed by assessing cell culture’s ability to predict virulence based on transcriptional response

    SciTech Connect

    Hayes, S L; Rodgers, M R; Lye, D J; Stelma, G N; McKinstry, Craig A.; Malard, Joel M.; Vesper, Sephen J.

    2007-10-01

    Aims: To assess the virulence of Aeromonas spp. using two models, a neonatal mouse assay and a mouse intestinal cell culture. Methods and Results: After artificial infection with a variety of Aeromonas spp., mRNA extracts from the two models were processed and hydridized to murine microarrays to determine host gene response. Definition of virulence was determined based on host mRNA production in murine neonatal intestinal tissue and mortality of infected animals. Infections of mouse intestinal cell cultures were then performed to determine whether this simpler model system’s mRNA responses correlated to neonatal results and therefore be predictive of virulence of Aeromonas spp. Virulent aeromonads up-regulated transcripts in both models including multiple host defense gene products (chemokines, regulation of transcription and apoptosis and cell signalling). Avirulent species exhibited little or no host response in neonates. Mortality results correlated well with both bacterial dose and average fold change of up-regulated transcripts in the neonatal mice. Conclusions: Cell culture results were less discriminating but showed promise as potentially being able to be predictive of virulence. Jun oncogene up-regulation in murine cell culture is potentially predictive of Aeromonas virulence. Significance and Impact of the Study: Having the ability to determine virulence of waterborne pathogens quickly would potentially assist public health officials to rapidly assess exposure risks.

  14. Aeromonas hydrophila bacteraemia and portal pyaemia.

    PubMed

    Tulsidas, H; Ong, Y Y; Chan, K C

    2008-04-01

    The Aeromonas species uncommonly cause disease in humans. We report portal pyaemia secondary to Aeromonas hydrophila bacteraemia occurring in a 71-year-old Chinese man with no history of hepatobiliary disease or malignancy. He presented with fever, rigors and abdominal bloating for four days and was subsequently found to have Aeromonas hydrophila bacteraemia, portal vein thrombosis and a psoas abscess. He was treated with ciprofloxacin and had a good recovery. Aeromonas hydrophila infection is an uncommon cause of intestinal and extraintestinal infection in man, but must be suspected in immunocompromised hosts and in those exposed to brackish or salt water. PMID:18418529

  15. Levofloxacin resistance of Helicobacter pylori strains isolated from patients in southern Poland, between 2006-2012.

    PubMed

    Karczewska, Elzbieta; Klesiewicz, Karolina; Wojtas-Bonior, Izabela; Skiba, Iwona; Sito, Edward; Czajecki, Krzysztof; Zwolińska-Wcisło, Małgorzata; Budak, Alicja

    2014-01-01

    An increasing resistance of Helicobacter pylori (H. pylori) to antimicrobial agents leads to the need of regional monitoring of the prevalence resistant strains (according to the Maastricht/Florence consensus report, 2012). The aim of the study was to assess the resistance to levofloxacin of H. pylori strains isolated from adult patients of Małopolska region in Poland. Bioptates taken from gastric mucosa during gastroscopy constituted the material for the study. Two hundred ten H. pylori strains were isolated from 811 patients. A majority of strains (171) came from patients before the treatment of H. pylori infections while the remaining 39 strains were isolated from patients after the failed therapy. Susceptibility of H. pylori to levofloxacin was determined by strips impregnated with antibiotic gradient (E-test, bioMerieux). The obtained minimum inhibitory concentration (MIC) values ranged from 0.002 mg/L to 32 mg/L. The percentage of strains resistant to levofloxacin amounted to 8.10% (17/210). Among the group of strains isolated from patients before the treatment, 5.85% (10/171) of H. pylori strains were resistant to levofloxacin. In the group of strains isolated from patients after the treatment 17.95% (7/39) of strains were resistant. The difference in the frequency of H. pylori strains resistant to levofloxacin in patients before and after the treatment of the infection due to H. pylori was statistically significant (p = 0.0297). The low percentage of H. pylori strains resistant to levofloxacin justify that the introduction of a triple therapy with levofloxacin is a good alternative in the treatment of H. pylori infections, especially in regions with high prevalence of H. pylori strains resistant to clarithromycin (> 20%).

  16. [Study on 190 strains of "staphylococcus aureus" isolated in a department of ophthalmology (author's transl)].

    PubMed

    Rossolini, A; Bianchini, A M; Partini, N; Frezzotti, R; Guerra, R

    1978-01-01

    Biochemical features and sensitivity to chemotherapeutic agents of 190 strains of Staphylococcus isolated from pharinx and conjunctiva of ophtalmological patients and staff were studied. Each strain was investigated for: pigment, coagulase, hemolysis (alpha-toxin), phosphatase and penicillinase production and mannite fermentation. Twentyfour chemotherapeutic angents were used for sensitivity tests. The Authors emphasize that a positive coagulase test is the best laboratory evidence for pathogenicity of a given strain of Staphylococcus, and that the site of isolation of the examined strains is not related with their biochemical features and sensitivity to chemotherapeutic agents. PMID:755453

  17. PCR screening and sequence analysis of iol clusters in Lactobacillus casei strains isolated from koumiss.

    PubMed

    Zhang, W; Sun, Z; Sun, T; Zhang, H

    2010-11-01

    The iol cluster (consisting of genes involved in myo-inositol utilization) was investigated in Lactobacillus casei strains isolated from koumiss. Ten strains were tested for the presence of iol cluster by PCR screening; three strains encoded this cluster. Full-sequencing procedure was conducted; the iol cluster was identical to that of L. casei BL23 (GenBank access. no. FM177140) except for an upstream transposase. The iol cluster is not a common feature for L. casei strains isolated from koumiss. PMID:21253906

  18. EVALUATION OF THERMOTOLERANT ACETOBACTER PASTEURIANUS STRAINS ISOLATED FROM MOROCCAN FRUITS CATALYZING OXIDATIVE FERMENTATION AT HIGH TEMPERATURE.

    PubMed

    Mounir, M; Shafiei, R; Zarmehrkhorshid, R; Hamouda, A; Alaoui, M Ismaili; Thonart, P

    2015-01-01

    Six strains of acetic acid bacteria were isolated from Moroccan local products and their potential as industrial strains was evaluated in lab-bioreactor. Three of them, namely TAV01, AF01 and CV01, isolated from traditional apple vinegar, apple and cactus fruit, respectively were selected and their responses to high temperature were assessed. Morphological and biochemical identification confirmed that these strains belong to Acetobacter species. Their growth and acetic acid production were compared with the thermoresistant reference strain, Acetobacter senegalensis and mesophilic strains of Acetobacter pasteurianus. The two strains AF01 and CV01 showed abundant growth and noticeable acetic acid production ability at high temperatures (38 to 41°C). A thermophilic character was observed for AF01 strain. Indeed, this bacterium grew better at 38 than 30°C. PMID:26630753

  19. Cold Shock Exoribonuclease R(VacB) is involved in Aeromonas hydrophila Virulence

    EPA Science Inventory

    In this study, we cloned and sequenced a virulence-associated gene (vacB) from a clinical isolate SSU of Aeromonas hydrophila. We identified this gene based on our recently annotated genome sequence of the environmental isolate ATCC 7966T of A. hydrophila and the vacB gene of Shi...

  20. Cold Shock Exoribonuclease R (VacB) is Involved in Aeromonas hydrophila Pathogenesis

    EPA Science Inventory

    In this study, we cloned and sequenced a virulence-associated gene (vacB) from a clinical isolate SSU of Aeromonas hydrophila. We identified this gene based on our recently annotated genome sequence of the environmental isolate ATCC 7966T of A. hydrophila and the vacB gene of Shi...

  1. Biosynthesis of prodigiosin by white strains of Serratia marcescens isolated from patients.

    PubMed

    Ding, M J; Williams, R P

    1983-03-01

    Serratia marcescens isolated from infected adults generally does not synthesize prodigiosin. Other investigators have reported that most clinical strains form a pigment if furnished with 4-methoxy-2,2'-bipyrrole-5-carboxyaldehyde (MBC), a precursor of prodigiosin. To determine whether the pigment was prodigiosin, we studied 65 white strains of S. marcescens isolated from patients. On the basis of response to MBC, we assigned the strains to one of three classes: class 1 (14 strains), strains remaining white; class 2 (48 strains), strains becoming gray or pink; and class 3 (3 strains), strains becoming blue. Ethanol extracts of bacteria of classes 2 and 3 did not behave like prodigiosin when acidified or alkalinized, and the pigment spectra were not similar to prodigiosin spectra. If strains of class 3 were furnished with MBC plus 2-methyl-3-amylpyrrole (MAP), the other immediate precursor of prodigiosin, the pigment synthesized was characteristic of prodigiosin. Strains of classes 1 and 2 responded identically to MBC plus MAP and MBC alone. Although the majority of S. marcescens white strains from patients formed pigments in the presence of MBC, the pigments were not prodigiosin. A few strains did synthesize prodigiosin, but only if furnished with both MBC and MAP.

  2. Virulence of Yersinia spp. strains isolated from non-human sources.

    PubMed

    Apfel, M I; Noleto, A L

    1991-01-01

    1. Strains of Yersinia enterocolitica, Y. intermedia, Y. frederiksenii and Y. kristensenii from non-human sources were examined for virulence factors. Four of these strains were positive for autoagglutination, three were calcium dependent at 37 degrees C, three produced lipase, five had the ability to bind Congo red, six had pyrazinamidase activity, and two had a 42 MDa plasmid. 2. One strain (Y. enterocolitica 0:5) was lethal for mice and had the ability to invade guinea pig eyes and HeLa cells. After inoculation of mice by the intravenous route, this strain was isolated from the cecum. The spleen, liver, kidneys and lymph nodes presented necrosis. After intragastric inoculation, the strain was isolated from all of the organs and tissues examined. 3. Three of the remaining strains invaded HeLa cells but none caused guinea pig conjunctivitis. 4. After intragastric inoculation, all the strains were isolated from the cecum but disappeared between days 3 and 6. After intravenous infection, three strains produced necrosis of the spleen and were more invasive, eliciting infection in various organs. The remaining strains caused hypertrophy and hyperplasia of Peyer's patches and/or lymph nodes. 5. These results indicate that Y. enterocolitica 0:5 can be considered as virulent as typical European Y. enterocolitica strains. The remaining strains perhaps induce a weak immune response independent of virulence factors.

  3. The First Macrolide-Resistant Bordetella pertussis Strains Isolated From Iranian Patients

    PubMed Central

    Shahcheraghi, Fereshteh; Nakhost Lotfi, Masoumeh; Nikbin, Vajiheh Sadat; Shooraj, Fahimeh; Azizian, Reza; Parzadeh, Masoumeh; Allahyar Torkaman, Mohammad Reza; Zahraei, Seyed Mohsen

    2014-01-01

    Background: Whooping cough was considered as one of the major causes of childhood morbidity and mortality worldwide. Resistant isolates of Bordetella pertussis to macrolides in some countries have been recently reported. Objectives: Recent reports on macrolide-resistant B. pertussis isolates and lack of evidence for such resistance in clinical isolates of the Iranian patients led the authors of the current study to study antibiotic susceptibility of the collected isolates in the country. Susceptibility of the B. pertussis isolates to three antibiotics was studied. Relatedness of the strains recovered in this research was also examined. Materials and Methods: The antibacterial activities of erythromycin, azithromycin, and clarithromycin antibiotics against the recovered isolates of 779 nasopharyngeal swabs were examined using MIC (Minimum Inhibitory Concentration) method. Relationship of the strains was characterized by Pulsed-field Gel Electrophoresis (PFGE). Results: Among the specimens, 11 cases (1.4%) were culture-positive. Among these isolates, only two isolates had high MIC values for erythromycin and clarithromycin. Pulsed-field gel electrophoresis analysis of the isolates revealed 6 PFGE profiles (A-F) among which three and two isolates had the same patterns in profiles A and B, respectively. Conclusions: Azithromycin can be a good drug of choice to treat patients infected by B. pertussis in Iran. Clonal relationship of the isolates showed that the same B. pertussis strains were isolated from different patients in Iran. PMID:25371806

  4. Direct evidence of recombination in the recA gene of Aeromonas bestiarum.

    PubMed

    Sanglas, Ariadna; Albarral, Vicenta; Farfán, Maribel; Lorén, J Gaspar; Fusté, M Carmen

    2016-03-01

    Two hundred and twenty-one strains representative of all Aeromonas species were characterized using the recA gene sequence, assessing its potential as a molecular marker for the genus Aeromonas. The inter-species distance values obtained demonstrated that recA has a high discriminatory power. Phylogenetic analysis, based on full-length gene nucleotide sequences, revealed a robust topology with clearly separated clusters for each species. The maximum likelihood tree showed the Aeromonas bestiarum strains in a well-defined cluster, containing a subset of four strains of different geographical origins in a deep internal branch. Data analysis provided strong evidence of recombination at the end of the recA sequences in these four strains. Intergenomic recombination corresponding to partial regions of the two adjacent genes recA and recX (248 bp) was identified between A. bestiarum (major parent) and Aeromonas eucrenophila (minor parent). The low number of recombinant strains detected (1.8%) suggests that horizontal flow between recA sequences is relatively uncommon in this genus. Moreover, only a few nucleotide differences were detected among these fragments, indicating that recombination has occurred recently. Finally, we also determined if the recombinant fragment could have influenced the structure and basic functions of the RecA protein, comparing models reconstructed from the translated amino acid sequences of our A. bestiarum strains with known Escherichia coli RecA structures.

  5. Genotypic diversity of Lactobacillus sanfranciscensis strains isolated from French organic sourdoughs.

    PubMed

    Lhomme, Emilie; Onno, Bernard; Chuat, Victoria; Durand, Karine; Orain, Servane; Valence, Florence; Dousset, Xavier; Jacques, Marie-Agnès

    2016-06-01

    Lactobacillus sanfranciscensis is the predominant key lactic acid bacterium in traditionally fermented sourdoughs. Despite its prevalence, sourdough and their related breads could be different regarding their physicochemical and sensorial characteristics. The intraspecific diversity of L. sanfranciscensis might explain these observations. Fifty-nine strains isolated from French sourdoughs were typed by a polyphasic approach including Multilocus Sequence Typing (MLST) and Pulsed-field Gel Electrophoresis (PFGE), in order to study their genotypic diversity. MLST scheme can be reduced from six to four gene fragments (gdh, gyrA, nox and pta) without a major loss of discrimination between strains. The genes mapA and pgmA are not good candidates for inclusion in an MLST scheme to type L. sanfranciscensis strains, as they could not be amplified for a set of 18 strains among the 59 studied. This method revealed 20 sequence types (STs). Of these, 19 STs were grouped in one clonal complex, showing a strong relatedness between these strains. PFGE using SmaI discriminated 41 pulsotypes and so distinguished isolates better than the MLST scheme. Both genotypic methods indicate a low diversity between strains isolated from the same sourdough and a higher diversity between strains isolated from different sourdoughs, suggesting an influence of baker practices and/or environmental conditions on the selection of strains. The use of these two methods targeting genetic variations gives an optimal genotypic characterization of L.sanfranciscensis strains. PMID:27015297

  6. Isolation and in vitro selection of actinomycetes strains as potential probiotics for aquaculture

    PubMed Central

    Bernal, Milagro García; Campa-Córdova, Ángel Isidro; Saucedo, Pedro Enrique; González, Marlen Casanova; Marrero, Ricardo Medina; Mazón-Suástegui, José Manuel

    2015-01-01

    Aim: This study was designed to describe a series of in vitro tests that may aid the discovery of probiotic strains from actinomycetes. Materials and Methods: Actinomycetes were isolated from marine sediments using four different isolation media, followed by antimicrobial activity and toxicity assessment by the agar diffusion method and the hemolysis of human blood cells, respectively. Extracellular enzymatic production was monitored by the hydrolysis of proteins, lipids and carbohydrates. Tolerance to different pH values and salt concentrations was also determined, followed by hydrophobicity analysis and genetic identification of the most promising strains. Results: Five out of 31 isolated strains showed antimicrobial activity against three Vibrio species. Three non-hemolytic strains (N7, RL8 and V4) among these active isolates yielded positive results in hydrophobicity tests and exhibited good growth at salt concentrations ranging from 0% to 10%, except strain RL8, which required a salt concentration >0.6%. Although these strains did not grow at pH<3, they showed different enzymatic activities. Phylogenetic analysis revealed that strains N7 and V4 have more than 99% identity with several Streptomyces species, whereas the closest matches to strain RL8 are Streptomyces panacagri and Streptomyces flocculus, with 98% and 98.2% similarity, respectively. Conclusion: Three actinomycetes strains showing probiotic-like properties were discovered using several in vitro tests that can be easily implemented in different institutions around the world. PMID:27047067

  7. Genotypic diversity of Lactobacillus sanfranciscensis strains isolated from French organic sourdoughs.

    PubMed

    Lhomme, Emilie; Onno, Bernard; Chuat, Victoria; Durand, Karine; Orain, Servane; Valence, Florence; Dousset, Xavier; Jacques, Marie-Agnès

    2016-06-01

    Lactobacillus sanfranciscensis is the predominant key lactic acid bacterium in traditionally fermented sourdoughs. Despite its prevalence, sourdough and their related breads could be different regarding their physicochemical and sensorial characteristics. The intraspecific diversity of L. sanfranciscensis might explain these observations. Fifty-nine strains isolated from French sourdoughs were typed by a polyphasic approach including Multilocus Sequence Typing (MLST) and Pulsed-field Gel Electrophoresis (PFGE), in order to study their genotypic diversity. MLST scheme can be reduced from six to four gene fragments (gdh, gyrA, nox and pta) without a major loss of discrimination between strains. The genes mapA and pgmA are not good candidates for inclusion in an MLST scheme to type L. sanfranciscensis strains, as they could not be amplified for a set of 18 strains among the 59 studied. This method revealed 20 sequence types (STs). Of these, 19 STs were grouped in one clonal complex, showing a strong relatedness between these strains. PFGE using SmaI discriminated 41 pulsotypes and so distinguished isolates better than the MLST scheme. Both genotypic methods indicate a low diversity between strains isolated from the same sourdough and a higher diversity between strains isolated from different sourdoughs, suggesting an influence of baker practices and/or environmental conditions on the selection of strains. The use of these two methods targeting genetic variations gives an optimal genotypic characterization of L.sanfranciscensis strains.

  8. [Sensitivity to drugs of Escherichia coli strains isolated from poultry with coli septicemia].

    PubMed

    Giurov, B

    1985-01-01

    Investigations were carried out into the susceptibility of a total of 223 strains of Escherichia coli to therapeutic agents with the employment of the disk diffusion method. The organisms were isolated from internal organs and bone marrow of birds died of coli septicaemia. The serologic classification of the strains was defined with the use of 88 anti-group OK-agglutinating sera obtained through hyperimmunization of rabbits with the following Escherichia coli serotypes: 01-063, 068, 071, 073, 075, 078, 086, 0101, 0103, 0111-0114, 0119, 0124, 0129, 0135-0141, 0146, 0147, and 0149. It was found that serologically the strains referred as follows: 01-41 strains, 02-70 strains, 04-2 strains, 08-3 strains, 026-1 strain, 078-70 strains, 0111-2 strains, 0103-1 strain, 0141-1 strain. The number of untypable strains amounted to 32. Highest number of strains proved sensitive to colistin--96.06%, the remaining drugs following in a descending order: flumequine--95.65%, apramycin - 95.5%, gentamycin--93.72%, amoxicillin--93,8%, amikacin--88.57%, carbenicillin--86.88%, furazolidone--83,13%, and kanamycin--79.36%. High was the percent of strains resistant to tetracycline--66.17%, spectinomycin--61.67%, ampicillin--51.12%, chloramphenicol--50.23%, and streptomycin--44.84%.

  9. Draft Genome Sequence of Brazilian Leptospira noguchii Serogroup Panama Strain U73, Isolated from Cattle.

    PubMed

    Moreno, Luisa Z; Loureiro, Ana P; Miraglia, Fabiana; Matajira, Carlos E C; Kremer, Frederico S; Eslabao, Marcos R; Dellagostin, Odir A; Lilenbaum, Walter; Moreno, Andrea M

    2015-10-15

    Leptospira noguchii is a current zoonotic pathogen in Brazil. Here, we report the draft genome sequence of the Brazilian L. noguchii serogroup Panama strain U73, isolated from asymptomatic cattle urine.

  10. Complete genome sequence of a Dengue virus serotype 4 strain isolated in Roraima, Brazil.

    PubMed

    Naveca, Felipe G; Souza, Victor C; Silva, George A V; Maito, Rodrigo M; Granja, Fabiana; Siqueira, Thalita; Acosta, Pablo O A

    2012-02-01

    Dengue is the most important arboviral disease worldwide. We report the complete genome sequence of a dengue virus serotype 4, genotype II strain isolated in 2010 from a patient with classical dengue fever in Boa Vista, Roraima, Brazil.

  11. Draft Genome Sequence of Serratia sp. Strain DD3, Isolated from the Guts of Daphnia magna.

    PubMed

    Poehlein, Anja; Freese, Heike M; Daniel, Rolf; Simeonova, Diliana D

    2014-01-01

    We report the draft genome sequence of Serratia sp. strain DD3, a gammaproteobacterium from the family Enterobacteriaceae. It was isolated from homogenized guts of Daphnia magna. The genome size is 5,274 Mb.

  12. Draft Genome Sequence of Serratia sp. Strain DD3, Isolated from the Guts of Daphnia magna

    PubMed Central

    Poehlein, Anja; Freese, Heike M.; Daniel, Rolf

    2014-01-01

    We report the draft genome sequence of Serratia sp. strain DD3, a gammaproteobacterium from the family Enterobacteriaceae. It was isolated from homogenized guts of Daphnia magna. The genome size is 5,274 Mb. PMID:25212623

  13. Draft Genome Sequence of Brazilian Leptospira noguchii Serogroup Panama Strain U73, Isolated from Cattle

    PubMed Central

    Moreno, Luisa Z.; Loureiro, Ana P.; Miraglia, Fabiana; Matajira, Carlos E. C.; Kremer, Frederico S.; Eslabao, Marcos R.; Dellagostin, Odir A.; Lilenbaum, Walter

    2015-01-01

    Leptospira noguchii is a current zoonotic pathogen in Brazil. Here, we report the draft genome sequence of the Brazilian L. noguchii serogroup Panama strain U73, isolated from asymptomatic cattle urine. PMID:26472831

  14. Genome Sequence of a Lactococcus lactis Strain Isolated from Salmonid Intestinal Microbiota.

    PubMed

    Opazo, Rafael; Gajardo, Felipe; Ruiz, Mauricio; Romero, Jaime

    2016-08-25

    Lactococcus lactis is a common inhabitant of the intestinal microbiota of salmonids, especially those in aquaculture systems. Here, we present a genome sequence of a Lactococcus lactis strain isolated from the intestinal contents of rainbow trout reared in Chile.

  15. Genome Sequences of Three Oenococcus oeni Strains Isolated from Maipo Valley, Chile

    PubMed Central

    2015-01-01

    Oenococcus oeni is part of the microbial terroir involved in wine production. Here, we present three genome sequences of O. oeni strains isolated from spontaneous malolactic fermentation of cultivar Cabernet Sauvignon Maipo Valley, Chile. PMID:26272563

  16. Complete genome sequences of two waterfowl-origin tembusu virus strains isolated in shandong province, china.

    PubMed

    Chen, Hao; Liu, Xin; Tang, Yi; Zhang, Ying; Ti, Jinfeng; Gao, Xuhui; Diao, Youxiang

    2013-01-01

    Here, we report the complete genome sequences of two tembusu virus strains, ZC-1 and LQ-1, isolated from ducks and geese, respectively, in 2012. Phylogenetic analysis showed that the nucleotide and amino acid sequences of the two strains are closely related to those of the TMUV isolates around Shandong province. The full-length genome sequences of two waterfowl-origin TMUVs provided herein will help to understand the molecular epidemiology of tembusu virus in China, which deserves further investigation. PMID:24356821

  17. A strain of pathogenic Naegleria isolated from a human nasal swab.

    PubMed

    Chang, S L; Healy, G R; McCabe, L; Shumaker, J B; Schultz, M G

    1975-01-01

    The 161A strain of Naegleria isolated from a human nasal swab and reported earlier was further studied for its growth pattern, cyst-wall appearance, cytopathic effect on primary monkey kidney cells, and pathogenicity in mice. Results obtained in the study establish the pathogenic status of this strain. This constitutes the first isolation of a pathogenic Naegleria from a human nasal cavity. PMID:829906

  18. Characterisation of Clostridium difficile strains isolated from Groote Schuur Hospital, Cape Town, South Africa.

    PubMed

    Kullin, B; Brock, T; Rajabally, N; Anwar, F; Vedantam, G; Reid, S; Abratt, V

    2016-10-01

    The C. difficile infection rate in South Africa is concerning. Many strains previously isolated from diarrhetic patients at Groote Schuur Hospital were ribotype 017. This study further characterised these strains with respect to their clonal relationships, antibiotic susceptibility, toxin production and various attributes impacting on pathogen colonisation. Multilocus variable-number tandem-repeat analysis (MLVA) was used to characterise all C. difficile isolates. Antibiotic susceptibility was determined by E-test and PCR-based analysis of the ermB, gyrA and gyrB genes. Auto-aggregation of cells was measured in broth, and biofilm formation observed in 24-well plates. Toxins were measured using the Wampole C DIFF TOX A/B II kit. Most isolates belonged to the ribotype 017 group. Identical MLVA types occurred in different wards over time, and several patients were infected with identical strains. All isolates were susceptible to vancomycin and metronidazole, but some ribotype 017 isolates showed reduced metronidazole susceptibility (≥2 mg l(-1)). Sixty-nine percent of ribotype 017 isolates were resistant to moxifloxacin, and 94 % to erythromycin, compared to 0 % and 17 % resistance, respectively, in non-ribotype 017 isolates. The ermB gene and mutations in the gyrA and/or gyrB genes were linked to erythromycin and moxifloxacin resistance, respectively. Ribotype 017 isolates auto-aggregated more strongly than other isolates and produced lower levels of the TcdB toxin than a reference strain. Certain strains produced strong biofilms. Patient-to-patient transfer and unique infection events could cause the predominance of ribotype 017 strains in the cohort. Multi-drug resistant strains are a potential reservoir for future infections.

  19. Primary Isolation Strain Determines Both Phage Type and Receptors Recognised by Campylobacter jejuni Bacteriophages

    PubMed Central

    Sørensen, Martine C. Holst; Gencay, Yilmaz Emre; Birk, Tina; Baldvinsson, Signe Berg; Jäckel, Claudia; Hammerl, Jens A.; Vegge, Christina S.; Neve, Horst; Brøndsted, Lone

    2015-01-01

    In this study we isolated novel bacteriophages, infecting the zoonotic bacterium Campylobacter jejuni. These phages may be used in phage therapy of C. jejuni colonized poultry to prevent spreading of the bacteria to meat products causing disease in humans. Many C. jejuni phages have been isolated using NCTC12662 as the indicator strain, which may have biased the selection of phages. A large group of C. jejuni phages rely on the highly diverse capsular polysaccharide (CPS) for infection and recent work identified the O-methyl phosphoramidate modification (MeOPN) of CPS as a phage receptor. We therefore chose seven C. jejuni strains each expressing different CPS structures as indicator strains in a large screening for phages in samples collected from free-range poultry farms. Forty-three phages were isolated using C. jejuni NCTC12658, NCTC12662 and RM1221 as host strains and 20 distinct phages were identified based on host range analysis and genome restriction profiles. Most phages were isolated using C. jejuni strains NCTC12662 and RM1221 and interestingly phage genome size (140 kb vs. 190 kb), host range and morphological appearance correlated with the isolation strain. Thus, according to C. jejuni phage grouping, NCTC12662 and NCTC12658 selected for CP81-type phages, while RM1221 selected for CP220-type phages. Furthermore, using acapsular ∆kpsM mutants we demonstrated that phages isolated on NCTC12658 and NCTC12662 were dependent on the capsule for infection. In contrast, CP220-type phages isolated on RM1221 were unable to infect non-motile ∆motA mutants, hence requiring motility for successful infection. Hence, the primary phage isolation strain determines both phage type (CP81 or CP220) as well as receptors (CPS or flagella) recognised by the isolated phages. PMID:25585385

  20. Cross-Comparison of Leaching Strains Isolated from Two Different Regions: Chambishi and Dexing Copper Mines

    PubMed Central

    Ngom, Baba; Liang, Yili; Liu, Xueduan

    2014-01-01

    A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa) and Dexing copper mine (China, Asia), was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different strains were characterized and compared at physiological level. The results revealed that, except for copper tolerance, strains within species presented almost similar physiological traits with slight advantages of Chambishi strains. However, in terms of leaching efficiency, native strains always achieved higher cell density and greater iron and copper extraction rates than the foreign microorganisms. In addition, microbial community analysis revealed that the different mixed cultures shared almost the same profile, and At. ferrooxidans strains always outcompeted the other strains. PMID:25478575

  1. Cross-comparison of leaching strains isolated from two different regions: Chambishi and Dexing copper mines.

    PubMed

    Ngom, Baba; Liang, Yili; Liu, Xueduan

    2014-01-01

    A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa) and Dexing copper mine (China, Asia), was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different strains were characterized and compared at physiological level. The results revealed that, except for copper tolerance, strains within species presented almost similar physiological traits with slight advantages of Chambishi strains. However, in terms of leaching efficiency, native strains always achieved higher cell density and greater iron and copper extraction rates than the foreign microorganisms. In addition, microbial community analysis revealed that the different mixed cultures shared almost the same profile, and At. ferrooxidans strains always outcompeted the other strains.

  2. Origin and characteristics of enteroinvasive strains of Escherichia coli (EIEC) isolated in Germany.

    PubMed Central

    Beutin, L.; Gleier, K.; Kontny, I.; Echeverria, P.; Scheutz, F.

    1997-01-01

    Thirty-five E. coli strains belonging to O-serogroups with enteroinvasive types of Escherichia coli (EIEC) isolated in Germany between 1989 and 1995 were investigated for invasivity-associated DNA sequences. Only 11 strains were positive for ipaH and thus confirmed as EIEC. All 11 EIEC isolates originated from human infections which were imported to Germany from Eastern Europe. EIEC O124 were most frequent and originated from asymptomatic Romanians arriving at Rostock, Germany in 1992 and 1993. In January 1993, EIEC O124 were isolated from faeces of a laboratory technician with diarrhoea working at the enteric pathogen department of the Institute of Hygiene in Rostock. By comparing her E. coli O124 isolate with recently imported O124 strains for Xba I restriction fragment length polymorphisms (RFLP) the probable source of infection could be determined. Four major RFLP patterns were found in the group of O124 strains. O124 strains with identical RFLP patterns were found in the group of 0124 strains. 0124 strains with identical RFLP patterns were isolated from people who were in close contact to each other. PMID:9207729

  3. Comparative characterization of Acinetobacter strains isolated from different foods and clinical sources.

    PubMed

    Gennari, M; Lombardi, P

    1993-11-01

    Eighty-three Acinetobacter strains from clinical sources, and 170 from various foods (including fresh and spoiled meat and fish, vegetables, raw milk and cheese) were identified according to recently improved taxonomy, using a computer-assisted probabilistic method based on phenotyping tests. Apart from some atypical characters, most of the strains (94%) were identified to belong to the genospecies or groups of genospecies described in the literature. Among our strains from hospitals, the A. calcoaceticus- A. baumannii complex predominated, whereas the strains isolated from food were predominated by genospecies 7 (A. johnsonii), followed by genospecies 8/9 (A. lwoffii). The isolates from clinical environments showed a major incidence of antibiotic resistance, haemolytic strains and strains producing polysaccharidic material.

  4. [The relationship of plasmids from environmental Yersinia isolates and the virulence plasmid of enteropathogenic Yersinia strains].

    PubMed

    Hoffmann, B; Strauch, E; Appel, B; Nattermann, H

    2002-01-01

    The human pathogenic strains of Yersinia harbour a conserved plasmid carrying the Yop virulon. The virulence plasmid of Yersinia enterocolitica strains belonging to the serogroups O:3 and O:9 were used as probes to detect homologous sequences in plasmids of "avirulent" Yersinia strains. "Avirulent" Yersinia strains (Y. enterocolitica biogroup 1A, Y. intermedia, Y. kristensenii and Y. frederiksenii) lack the virulence plasmid. They are widely distributed in the environment and can frequently be isolated from clinical samples. Hybridisation experiments revealed a number of common genetic elements of the virulence plasmid and the plasmids of "avirulent" Yersinia strains. These elements were identified as genes involved in plasmid replication, as an endonuclease gene and as mobile genetic elements. However, none of the plasmid encoded virulence genes was present in the plasmids of "avirulent" Yersinia strains. The frequent occurrence and the possible etiological relevance of "avirulent" isolates will be discussed.

  5. Full-genome sequence analysis of a multirecombinant echovirus 3 strain isolated from sewage in Greece.

    PubMed

    Kyriakopoulou, Zaharoula; Dedepsidis, Evaggelos; Pliaka, Vaia; Tsakogiannis, Dimitris; Pratti, Anastassia; Levidiotou-Stefanou, Stamatina; Markoulatos, Panayotis

    2010-05-01

    An echovirus 3 (Echo3) strain (strain LR31G7) was isolated from a sewage treatment plant in Greece in 2005. Full-genome molecular, phylogenetic, and SimPlot analyses were conducted in order to reveal the evolutionary pathways of the isolate. Nucleotide and phylogenetic analyses of part of the VP1 genomic region revealed that the isolated strain correlates with Echo3 strains isolated during the same year in France and Japan, implying that the same virus circulated in Europe and Asia. LR31G7 was found to be a recombinant that shares the 3' part of its genome with an Echo25 strain isolated from asymptomatic infants in Norway in 2003. Nucleotide and SimPlot analyses of the VP1-2A junction, where the recombination was located, revealed the exact recombination breakpoint (nucleotides 3357 to 3364). Moreover, there is evidence that recombination events had occurred in 3B-3D region in the evolutionary history of the isolate. Our study indicates that recombination events play major roles in enterovirus evolution and that the circulation of multirecombinant strains with unknown properties could be potentially dangerous for public health.

  6. Variable Characteristics of Bacteriocin-Producing Streptococcus salivarius Strains Isolated from Malaysian Subjects

    PubMed Central

    Barbour, Abdelahhad; Philip, Koshy

    2014-01-01

    Background Salivaricins are bacteriocins produced by Streptococcus salivarius, some strains of which can have significant probiotic effects. S. salivarius strains were isolated from Malaysian subjects showing variable antimicrobial activity, metabolic profile, antibiotic susceptibility and lantibiotic production. Methodology/Principal Findings In this study we report new S. salivarius strains isolated from Malaysian subjects with potential as probiotics. Safety assessment of these strains included their antibiotic susceptibility and metabolic profiles. Genome sequencing using Illumina’s MiSeq system was performed for both strains NU10 and YU10 and demonstrating the absence of any known streptococcal virulence determinants indicating that these strains are safe for subsequent use as probiotics. Strain NU10 was found to harbour genes encoding salivaricins A and 9 while strain YU10 was shown to harbour genes encoding salivaricins A3, G32, streptin and slnA1 lantibiotic-like protein. Strain GT2 was shown to harbour genes encoding a large non-lantibiotic bacteriocin (salivaricin-MPS). A new medium for maximum biomass production buffered with 2-(N-morpholino)ethanesulfonic acid (MES) was developed and showed better biomass accumulation compared with other commercial media. Furthermore, we extracted and purified salivaricin 9 (by strain NU10) and salivaricin G32 (by strain YU10) from S. salivarius cells grown aerobically in this medium. In addition to bacteriocin production, S. salivarius strains produced levan-sucrase which was detected by a specific ESI-LC-MS/MS method which indicates additional health benefits from the developed strains. Conclusion The current study established the bacteriocin, levan-sucrase production and basic safety features of S. salivarius strains isolated from healthy Malaysian subjects demonstrating their potential for use as probiotics. A new bacteriocin-production medium was developed with potential scale up application for pharmaceuticals

  7. Genome Sequence of Marinobacter sp. Strain MCTG268 Isolated from the Cosmopolitan Marine Diatom Skeletonema costatum

    PubMed Central

    Whitman, William B.; Huntemann, Marcel; Copeland, Alex; Chen, Amy; Kyrpides, Nikos; Markowitz, Victor; Pillay, Manoj; Ivanova, Natalia; Mikhailova, Natalia; Ovchinnikova, Galina; Andersen, Evan; Pati, Amrita; Stamatis, Dimitrios; Reddy, T. B. K.; Ngan, Chew Yee; Chovatia, Mansi; Daum, Chris; Shapiro, Nicole; Cantor, Michael N.; Woyke, Tanja

    2016-01-01

    Marinobacter sp. strain MCTG268 was isolated from the cosmopolitan marine diatom Skeletonema costatum and can degrade oil hydrocarbons as sole sources of carbon and energy. Here, we present the genome sequence of this strain, which is 4,449,396 bp with 4,157 genes and an average G+C content of 57.0%. PMID:27609918

  8. Meroparamycin production by newly isolated Streptomyces sp. strain MAR01: taxonomy, fermentation, purification and structural elucidation.

    PubMed

    El-Naggar, Moustafa Y; El-Assar, Samy A; Abdul-Gawad, Sahar M

    2006-08-01

    Twelve actinomycete strains were isolated from Egyptian soil. The isolated actinomycete strains were then screened with regard to their potential to generate antibiotics. The most potent of the producer strains was selected and identified. The cultural and physiological characteristics of the strain identified the strain as a member of the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene (1.5 kb) of the most potent strain evidenced a 99% similarity with Streptomyces spp. and S. aureofaciens 16S rRNA genes, and the isolated strain was ultimately identified as Streptomyces sp. MAR01. The extraction of the fermentation broth of this strain resulted in the isolation of one major compound, which was active in vitro against gram-positive, gram-negative representatives and Candida albicans. The chemical structure of this bioactive compound was elucidated based on the spectroscopic data obtained from the application of MS, IR, UV, 1H NMR, 13C NMR, and elemental analysis techniques. Via comparison to the reference data in the relevant literature and in the database search, this antibiotic, which had a molecular formula of C19H29NO2 and a molecular weight of 303.44, was determined to differ from those produced by this genus as well as the available known antibiotics. Therefore, this antibiotic was designated Meroparamycin. PMID:16953179

  9. Draft Genome Sequence of an Oceanobacillus sp. Strain Isolated from Soil in a Burial Crypt

    PubMed Central

    Arizaga, Ylenia; Bikandi, Joseba; Garaizar, Javier; Ganau, Giulia; Paglietti, Bianca; Deligios, Massimo; Rubino, Salvatore

    2016-01-01

    We present the draft genome of an Oceanobacillus sp. strain isolated from spores found in soil samples from a burial crypt of the Cathedral of Sant'Antonio Abate in Castelsardo, Italy. The data obtained indicated the closest relation of the strain with Oceanobacillus caeni. PMID:27469952

  10. Six Pseudoalteromonas Strains Isolated from Surface Waters of Kabeltonne, Offshore Helgoland, North Sea

    PubMed Central

    Wichels, Antje; Sullivan, Matthew B.

    2016-01-01

    Draft genomes are presented for 6 Pseudoalteromonas sp. strains isolated from surface waters at Kabeltonne, Helgoland, a long-term ecological research station in the North Sea. These strains contribute knowledge of the genomic underpinnings of a developing model system to study phage-host dynamics of a particle-associated ocean copiotroph. PMID:26868390

  11. Draft Genome Sequence of Clostridium tyrobutyricum Strain DIVETGP, Isolated from Cow's Milk for Grana Padano Production.

    PubMed

    Soggiu, Alessio; Piras, Cristian; Gaiarsa, Stefano; Bendixen, Emøke; Panitz, Frank; Bendixen, Christian; Sassera, Davide; Brasca, Milena; Bonizzi, Luigi; Roncada, Paola

    2015-01-01

    We announce the draft genome sequence of Clostridium tyrobutyricum strain DIVETGP. This strain was isolated from cow's milk used for Grana Padano cheese production. The genome was obtained using Illumina HiSeq technology and comprises 45 contigs for 3,018,999 bp, with a G+C content of 30.8%.

  12. Genome assemblies for 11 Yersinia pestis strains isolated in the Caucasus region

    SciTech Connect

    Zhgenti, Ekaterine; Johnson, Shannon L.; Davenport, Karen W.; Chanturia, Gvantsa; Daligault, Hajnalka E.; Chain, Patrick S.; Nikolich, Mikeljon P.

    2015-09-17

    Yersinia pestis, the causative agent of plague, is endemic to the Caucasus region but few reference strain genome sequences from that region are available. We present the improved draft or finished assembled genomes from 11 strains isolated in the nation of Georgia and surrounding countries.

  13. Genome assemblies for 11 Yersinia pestis strains isolated in the Caucasus region

    DOE PAGES

    Zhgenti, Ekaterine; Johnson, Shannon L.; Davenport, Karen W.; Chanturia, Gvantsa; Daligault, Hajnalka E.; Chain, Patrick S.; Nikolich, Mikeljon P.

    2015-09-17

    Yersinia pestis, the causative agent of plague, is endemic to the Caucasus region but few reference strain genome sequences from that region are available. We present the improved draft or finished assembled genomes from 11 strains isolated in the nation of Georgia and surrounding countries.

  14. Draft Genome Sequence of Micromonospora sp. Strain HK10, Isolated from Kaziranga National Park, India

    PubMed Central

    Talukdar, Madhumita; Das, Dhrubajyoti; Borah, Chiranjeeta; Deka Boruah, Hari Prasanna; Bora, Tarun Chandra

    2016-01-01

    We report the 6.92-Mbp genome sequence of Micromonospora sp. HK10, isolated from soil samples collected from Kaziranga National Park, Assam, India. The full genome of strain Micromonospora sp. strain HK10 consists of 6,911,179 bp with 73.39% GC content, 6,196 protein-coding genes, and 86 RNAs. PMID:27516496

  15. Draft Genome Sequence of Pedobacter sp. Strain Hv1, an Isolate from Medicinal Leech Mucosal Castings

    PubMed Central

    Ott, Brittany M.; Beka, Lidia; Graf, Joerg

    2015-01-01

    The Pedobacter sp. Hv1 strain was isolated from the medicinal leech, Hirudo verbana, mucosal castings. These mucosal sheds have been demonstrated to play a role in horizontal symbiont transmission. Here, we report the draft 4.9 Mbp genome sequence of Pedobacter sp. strain Hv1. PMID:26679583

  16. Draft genome sequences of 26 porphyromonas strains isolated from the canine oral microbiome.

    PubMed

    Coil, David A; Alexiev, Alexandra; Wallis, Corrin; O'Flynn, Ciaran; Deusch, Oliver; Davis, Ian; Horsfall, Alexander; Kirkwood, Nicola; Jospin, Guillaume; Eisen, Jonathan A; Harris, Stephen; Darling, Aaron E

    2015-01-01

    We present the draft genome sequences for 26 strains of Porphyromonas (P. canoris, P. gulae, P. cangingavalis, P. macacae, and 7 unidentified) and an unidentified member of the Porphyromonadaceae family. All of these strains were isolated from the canine oral cavity, from dogs with and without early periodontal disease. PMID:25858832

  17. Complete genome sequence of Streptococcus salivarius PS4, a strain isolated from human milk.

    PubMed

    Martín, Virginia; Maldonado-Barragán, Antonio; Jiménez, Esther; Ruas-Madiedo, Patricia; Fernández, Leónides; Rodríguez, Juan M

    2012-08-01

    Streptococcus salivarius is a commensal species commonly found in the human oropharyngeal tract. Some strains of this species have been developed for use as oral probiotics, while others have been associated with a variety of opportunistic human infections. Here, we report the complete sequence of strain PS4, which was isolated from breast milk of a healthy woman. PMID:22843595

  18. Genome Sequences of 14 Firmicutes Strains Isolated from the Human Vagina.

    PubMed

    Deitzler, Grace E; Ruiz, Maria J; Weimer, Cory; Park, SoEun; Robinson, Lloyd; Hallsworth-Pepin, Kymberlie; Wollam, Aye; Mitreva, Makedonka; Lewis, Amanda L; Lewis, Warren G

    2016-01-01

    Research on vaginal infections is currently limited by a lack of available fully sequenced bacterial reference strains. Here, we present strains (now available through BEI Resources) and genome sequences for a set of 14 vaginal isolates from the phylum Firmicutes These genome sequences provide a valuable resource for future research in understanding the role of Gram-positive bacteria in vaginal health and disease.

  19. [Occurrence and antimicrobial susceptibility of Morganella morganii strains isolated from clinical samples].

    PubMed

    Zalas-Wiecek, Patrycja; Gospodarek, Eugenia; Wróblewska, Joanna

    2012-01-01

    The aim of this study was the evaluation of occurrence and antimicrobial susceptibility of M morganii rods isolated from clinical samples. This study included 201 strains isolated in the Clinical Microbiology Department of Dr. A. Jurasz University Hospital in 2008-2010. Identification to species was carried out on the basis of the results of biochemical reactions included in the tests ID 32E and VITEK2 GN. Antimicrobial susceptibility of M. morganii rods was determined by the disk-diffusion method on Mueller-Hinton II Agar. Strains of M morganii most commonly isolated from skin and soft tissue, and material taken from the urinary tract, mainly from patients of Anesthesiology and Intensive Care Unit, Department of General and Vascular Surgery and Department of General Surgery and Endocrinology. All of M morganii strains isolated during the three years were susceptible to carbapenems. We reported decrease of strains susceptible to piperacillin and chloramphenicol. In 2010 we showed a higher percentage of strains intermediate to tigecycline, compared with 2009. We observed increase in the percentage of strains resistant to cefoperazone with sulbactam and reported decrease in the percentage of strains resistant and intermediate to aminoglycosides. Extended Spectrum Beta-Lactamases were produced by 13 (6,5%) of M morganii strains.

  20. Genome sequence of Janthinobacterium sp. strain PAMC 25724, isolated from alpine glacier cryoconite.

    PubMed

    Kim, Su Jin; Shin, Seung Chul; Hong, Soon Gyu; Lee, Yung Mi; Lee, Hyoungseok; Lee, Jungeun; Choi, In-Geol; Park, Hyun

    2012-04-01

    The draft genome of Janthinobacterium sp. strain PAMC 25724, which is a violacein-producing psychrotolerant bacterium, was determined. The strain was isolated from glacier cryoconite of the Alps mountain permafrost region. The sequence will allow identification and characterization of the genetic determination of its cold-adaptive properties.

  1. Complete Genome Sequence of Photobacterium sp. Strain J15, Isolated from Seawater of Southwestern Johor, Malaysia

    PubMed Central

    Roslan, Noordiyanah Nadhirah; Oslan, Siti Nurbaya; Baharum, Syarul Nataqain; Leow, Thean Chor

    2016-01-01

    Here, we report the genome sequences of Photobacterium sp. strain J15, isolated from seawater in Johor, Malaysia, with the ability to produce lipase and asparaginase. The PacBio genome sequence analysis of Photobacterium sp. strain J15 generated revealed its potential in producing enzymes with different catalytic functions. PMID:27469962

  2. Complete Genome Sequence of Photobacterium sp. Strain J15, Isolated from Seawater of Southwestern Johor, Malaysia.

    PubMed

    Roslan, Noordiyanah Nadhirah; Sabri, Suriana; Oslan, Siti Nurbaya; Baharum, Syarul Nataqain; Leow, Thean Chor

    2016-01-01

    Here, we report the genome sequences of Photobacterium sp. strain J15, isolated from seawater in Johor, Malaysia, with the ability to produce lipase and asparaginase. The PacBio genome sequence analysis of Photobacterium sp. strain J15 generated revealed its potential in producing enzymes with different catalytic functions. PMID:27469962

  3. Complete Genome Sequences of Sulfurospirillum Strains UCH001 and UCH003 Isolated from Groundwater in Japan

    PubMed Central

    Miura, Takamasa; Uchino, Yoshihito; Tsuchikane, Keiko; Ohtsubo, Yoshiyuki; Ohji, Shoko; Hosoyama, Akira; Ito, Masako; Takahata, Yoh; Yamazoe, Atsushi; Suzuki, Ken-ichiro

    2015-01-01

    Sulfurospirillum strains UCH001 and UCH003 were isolated from anaerobic cis-1,2-dichloroethene-dechlorinating microbial consortia derived from groundwater in Japan. Here, we report the complete genome sequences of strains UCH001 and UCH003. PMID:25814615

  4. Complete Genome Sequence of Streptococcus salivarius PS4, a Strain Isolated from Human Milk

    PubMed Central

    Martín, Virginia; Maldonado-Barragán, Antonio; Jiménez, Esther; Ruas-Madiedo, Patricia; Fernández, Leónides

    2012-01-01

    Streptococcus salivarius is a commensal species commonly found in the human oropharyngeal tract. Some strains of this species have been developed for use as oral probiotics, while others have been associated with a variety of opportunistic human infections. Here, we report the complete sequence of strain PS4, which was isolated from breast milk of a healthy woman. PMID:22843595

  5. Draft Genome Sequences of Three Strains of Geobacillus stearothermophilus Isolated from a Milk Powder Manufacturing Plant

    PubMed Central

    Burgess, Sara A.; Cox, Murray P.; Flint, Steve H.; Lindsay, Denise

    2015-01-01

    Three strains of Geobacillus stearothermophilus (designated A1, P3, and D1) were isolated from a New Zealand milk powder manufacturing plant. Here, we describe their draft genome sequences. This information provided the first genomic insights into the nature of G. stearothermophilus strains present in the milk powder manufacturing environment. PMID:26472822

  6. Genome Sequence of Marinobacter sp. Strain MCTG268 Isolated from the Cosmopolitan Marine Diatom Skeletonema costatum.

    PubMed

    Gutierrez, Tony; Whitman, William B; Huntemann, Marcel; Copeland, Alex; Chen, Amy; Kyrpides, Nikos; Markowitz, Victor; Pillay, Manoj; Ivanova, Natalia; Mikhailova, Natalia; Ovchinnikova, Galina; Andersen, Evan; Pati, Amrita; Stamatis, Dimitrios; Reddy, T B K; Ngan, Chew Yee; Chovatia, Mansi; Daum, Chris; Shapiro, Nicole; Cantor, Michael N; Woyke, Tanja

    2016-01-01

    Marinobacter sp. strain MCTG268 was isolated from the cosmopolitan marine diatom Skeletonema costatum and can degrade oil hydrocarbons as sole sources of carbon and energy. Here, we present the genome sequence of this strain, which is 4,449,396 bp with 4,157 genes and an average G+C content of 57.0%. PMID:27609918

  7. Isolation and Characterization of Rhamnolipid-Producing Bacterial Strains from a Biodiesel Facility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Novel strains of rhamnolipid-producing bacteria were isolated from soils at a biodiesel facility on the basis of their ability to grow on glycerol as a sole carbon source. Strains were identified as Acinetobacter calcoaceticus, Enterobacter asburiae, E. hormaecheii, Pantoea stewartii and Pseudomona...

  8. Large scale analysis of virulence genes in Escherichia coli strains isolated from Avalon Bay, CA.

    PubMed

    Hamilton, Matthew J; Hadi, Asbah Z; Griffith, John F; Ishii, Satoshi; Sadowsky, Michael J

    2010-10-01

    Contamination of recreational waters with Escherichia coli and Enterococcus sp. is a widespread problem resulting in beach closures and loss of recreational activity. While E. coli is frequently used as an indicator of fecal contamination, and has been extensively measured in waterways, few studies have examined the presence of potentially pathogenic E. coli strains in beach waters. In this study, a combination of high-throughput, robot-assisted colony hybridization and PCR-based analyses were used to determine the genomic composition and frequency of virulence genes present in E. coli isolated from beach water in Avalon Bay, Santa Catalina Island, CA. A total of 24,493 E. coli isolates were collected from two sites at a popular swimming beach between August through September 2007 and from July through August 2008. All isolates were examined for the presence of shiga-like toxins (stx1/stx2), intimin (eaeA), and enterotoxins (ST/LT). Of the 24,493 isolates examined, 3.6% contained the eaeA gene, indicating that these isolates were potential EPEC strains. On five dates, however, greater than 10% of the strains were potential EPEC, suggesting that incidence of virulence genes at this beach has a strong temporal component. No STEC or ETEC isolates were detected, and only eight (<1.0%) of the potential EPEC isolates were found to carry the EAF plasmid. The potential EPEC isolates mainly belonged to E. coli phylogenetic groups B1 or B2, and carried the β intimin subtype. DNA fingerprint analyses of the potential EPEC strains indicated that the isolates belonged to several genetically diverse groups, although clonal isolates were frequently detected. While the presence of virulence genes alone cannot be used to determine the pathogenicity of strains, results from this study show that potential EPEC strains can be found in marine beach water and their presence needs to be considered as one of the factors used in decisions concerning beach closures. PMID:20643468

  9. Phenotypic characterization of Clostridium botulinum strains isolated from infant botulism cases in Argentina.

    PubMed

    Sagua, M D; Lúquez, C; Barzola, C P; Bianco, M I; Fernández, R A

    2009-01-01

    Infant botulism is the most common form of human botulism; however, its transmission has not been completely explained yet. Some of the most recognized potential sources of Clostridium botulinum spores are the soil, dust, honey and medicinal herbs. In Argentina, 456 cases of infant botulism were reported between 1982 and 2007. C. botulinum type A was identified in 455 of these cases whereas type B was identified in just one case. However, in Argentina, types A, B, E, F, G, and Af have been isolated from environmental sources. It is not clearly known if strains isolated from infant botulism cases have different characteristics from strains isolated from other sources. During this study, 46 C. botulinum strains isolated from infant botulism cases and from environmental sources were typified according to phenotypic characteristics. Biochemical tests, antimicrobial activity, and haemagglutinin-negative botulinum neurotoxin production showed uniformity among all these strains. Despite the variability observed in the botulinum neurotoxin's binding to cellular receptors, no correlation was found between these patterns and the source of the botulinum neurotoxin. However, an apparent geographical clustering was observed, since strains isolated from Argentina had similar characteristics to those isolated from Italy and Japan, but different to those isolated from the United States. PMID:19831311

  10. Rhodococcus baikonurensis BTM4c, a boron-tolerant actinobacterial strain isolated from soil.

    PubMed

    Yoon, Jaewoo; Miwa, Hiroki; Ahmed, Iftikhar; Yokota, Akira; Fujiwara, Toru

    2010-01-01

    By screening a bacterial population from the soil in Tokyo, Japan, we isolated a boron-tolerant bacterium, strain BTM4c. Strain BTM4c grew under the boron excess conditions with 100 mM boric acid, which is generally toxic to bacteria. Molecular phylogenetic, chemotaxonomic, and physiological data showed that the strain belongs to the genus Rhodococcus, and is to be identified as Rhodococcus baikonurensis. PMID:20057133

  11. Characterization of functional properties of Enterococcus faecium strains isolated from human gut.

    PubMed

    İspirli, Hümeyra; Demirbaş, Fatmanur; Dertli, Enes

    2015-11-01

    The aim of this work was to characterize the functional properties of Enterococcus faecium strains identified after isolation from human faeces. Of these isolates, strain R13 showed the best resistance to low pH, bile salts, and survival in the simulated in vitro digestion assay, and demonstrated an important level of adhesion to hexadecane as a potential probiotic candidate. Analysis of the antibiotic resistance of E. faecium strains indicated that in general these isolates were sensitive to the tested antibiotics and no strain appeared to be resistant to vancomycin. Examination of the virulence determinants for E. faecium strains demonstrated that all strains contained the virulence genes common in gut- and food-originated enterococci, and strain R13 harboured the lowest number of virulence genes. Additionally, no strain contained the genes related to cytolysin metabolism and showed hemolytic activity. The antimicrobial role of E. faecium strains was tested against several pathogens, in which different levels of inhibitory effects were observed, and strain R13 was inhibitory to all tested pathogens. PCR screening of genes encoding enterocin A and B indicated the presence of these genes in E. faecium strains. Preliminary characterization of bacteriocins revealed that their activity was lost after proteolytic enzyme treatments, but no alteration in antimicrobial activity was observed at different pHs (3.5 to 9.5) and after heat treatments. In conclusion, this study revealed the functional characteristics of E. faecium R13 as a gut isolate, and this strain could be developed as a new probiotic after further tests.

  12. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese.

    PubMed

    Martino, Gabriela P; Quintana, Ingrid M; Espariz, Martín; Blancato, Victor S; Gallina Nizo, Gabriel; Esteban, Luis; Magni, Christian

    2016-02-04

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production.

  13. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese

    PubMed Central

    Martino, Gabriela P.; Quintana, Ingrid M.; Espariz, Martín; Blancato, Victor S.; Gallina Nizo, Gabriel; Esteban, Luis

    2016-01-01

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production. PMID:26847907

  14. [Virulence and biochemical activity of Aspergillus fumigatus strains isolated from cow fetuses].

    PubMed

    Venev, S

    1977-01-01

    Tested was the virulence of 20 strains of Aspergillus fumigatus isolated from cow fetuses. All laboratory mice injected with them died, and the pregnant guinea pigs aborted. It was demonstrated that these strains contain exogenic and endotoxic substances which are extracted effectively with alcohol and ether. The mould cultures showed proteolytic, amylolytic, cellulose, and organic acid activity. The biochemical and pathogenic potential of the strains were of great importance for causing abortion. PMID:339512

  15. Virulent Aeromonas hydrophila in channel catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we investigated factors that predisposed catfish to motile aeromonas septicemia (MAS) caused by virulent Aeromonas hydrophila (vAh). Our results revealed that wounding on fish body surface was a prerequisite for vAh infection and disease development. A reproducible waterborne challeng...

  16. Clonal analysis of Staphylococcus hominis strains isolated from hospitalized patients.

    PubMed

    Szczuka, Ewa; Trawczyński, Krzysztof; Kaznowski, Adam

    2014-01-01

    Staphylococcus hominis is a part of normal skin flora, but it is also a cause of nosocomial infections. The aim of this study was to investigate the genetic relatedness of 62 strains of S. hominis obtained from hospitalised patients during an 11-year period. For the discrimination of these clinical strains we used repetitive sequence-based PCR method (BOX-PCR) and multiple-locus variable-number tandem repeat analysis (MLVA). BOX-PCR analysis revealed a large genetic diversity among clinical strains and we did not find a predominant clone with the ability to persist in a hospital environment. MLVA is not as discriminatory as BOX fingerprinting and would not be a useful method for epidemiological studies.

  17. Detection of Aeromonas caviae in the common housefly Musca domestica by culture and polymerase chain reaction.

    PubMed

    Nayduch, D; Honko, A; Noblet, G P; Stutzenberger, F

    2001-12-01

    Aeromonas caviae has been implicated in diarrhoeal disease of livestock and humans. The potential role of houseflies in the epidemiology of this pathogen was investigated by examining the prevalence of A. caviae in houseflies collected from two South Carolina farms and one restaurant. Isolation was accomplished by culture of flies in alkaline peptone water followed by identification with Aeromonas-specific PCR using novel primers (APW-PCR). All isolates cultured from houseflies were identified as A. caviae by biochemical characteristics and direct sequencing approximately 800 bp of the 16S rRNA gene. Aeromonas caviae was detected in 78% (272/349) dairy farm flies, 55% (54/99) pig farm flies and 39% (77/200) restaurant flies. Faeces from cows and pigs at the farms also were positive for A. caviae (58% and 100%, respectively). The APW PCR method provided a rapid, convenient way to identify A. caviae from faeces and houseflies that contained hundreds of bacterial species.

  18. [Aeromonas hydrophila in waters of Lake San Roque and its tributaries].

    PubMed

    Fracchia de Salvay, Y

    1986-01-01

    The presence of Aeromonas hydrophila in 72 samples of water of Lake San Roque and two rivers that flow into it, situated in Punilla Valley, Córdoba was investigated. Water-peptone Alkaline (enrichment medium) and Rippey Cabelli Agar without ampicillin (selective and differential medium for Aeromonas hydrophila) were used for isolation. The colonies obtained were assayed by oxidase test and subsequent oxidation-fermentation of Hugh Leifson, motility, urease, mannitol and trehalose fermentation, ornithine and lysine decarboxylation. Voges Proskauer and gas production from glucose and glycerol. Aeromonas hydrophila was isolated in 13% of water samples obtained in days with high temperature. Although this finding is not alarming, its presence should be taken into account because of its potential pathogenesis.

  19. Resistance patterns of Campylobacter spp. strains isolated from poultry carcasses in a big Swiss poultry slaughterhouse.

    PubMed

    Frediani-Wolf, V; Stephan, R

    2003-12-31

    The aim of this study was to determine resistance patterns of strains of Campylobacter spp. isolated from poultry carcasses in one of the two big Swiss poultry slaughterhouses. A variety of antibiotics with clinical relevance in human and/or in veterinary medicine was tested. In addition, the results of the disc diffusion method, E-test and microdilution broth methods were compared. Of the 195 Campylobacter jejuni strains isolated from 195 poultry carcasses from 21 flocks, 134 strains were susceptible in vitro to all tested antibiotics. Sixty-one strains (31.3%, from eight flocks) showed resistance. Forty-one strains were resistant to a single antibiotic-34 to streptomycin, 6 to ampicillin and 1 to ciprofloxacin. Eighteen strains (from two flocks) showed combined resistance to erythromycin and streptomycin, two strains to ciprofloxacin and streptomycin. None of the isolates was resistant to tetracycline. The data of this first study in Switzerland show a favourable resistance situation for C. jejuni strains against erythromycin, tetracycline and ciprofloxacin. The disc diffusion method was found to be a reliable and easy tool for monitoring the prevalence of resistant C. jejuni strains. For surveillance of changes in the susceptibility concentration levels to antimicrobial agents, however, a MIC method should be used. Further investigations along the whole poultry production chain (farm, slaughterhouse and retail levels) are now necessary in order to confirm the resistance situation.

  20. Nitrogen-Fixing Rhizobial Strains Isolated from Common Bean Seeds: Phylogeny, Physiology, and Genome Analysis

    PubMed Central

    Mora, Yolanda; Díaz, Rafael; Vargas-Lagunas, Carmen; Peralta, Humberto; Guerrero, Gabriela; Aguilar, Alejandro; Encarnación, Sergio; Girard, Lourdes

    2014-01-01

    Rhizobial bacteria are commonly found in soil but also establish symbiotic relationships with legumes, inhabiting the root nodules, where they fix nitrogen. Endophytic rhizobia have also been reported in the roots and stems of legumes and other plants. We isolated several rhizobial strains from the nodules of noninoculated bean plants and looked for their provenance in the interiors of the seeds. Nine isolates were obtained, covering most known bean symbiont species, which belong to the Rhizobium and Sinorhizobium groups. The strains showed several large plasmids, except for a Sinorhizobium americanum isolate. Two strains, one Rhizobium phaseoli and one S. americanum strain, were thoroughly characterized. Optimal symbiotic performance was observed for both of these strains. The S. americanum strain showed biotin prototrophy when subcultured, as well as high pyruvate dehydrogenase (PDH) activity, both of which are key factors in maintaining optimal growth. The R. phaseoli strain was a biotin auxotroph, did not grow when subcultured, accumulated a large amount of poly-β-hydroxybutyrate, and exhibited low PDH activity. The physiology and genomes of these strains showed features that may have resulted from their lifestyle inside the seeds: stress sensitivity, a ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) complex, a homocitrate synthase (usually present only in free-living diazotrophs), a hydrogenase uptake cluster, and the presence of prophages. We propose that colonization by rhizobia and their presence in Phaseolus seeds may be part of a persistence mechanism that helps to retain and disperse rhizobial strains. PMID:25002426

  1. Isolating and evaluating lactic acid bacteria strains for effectiveness of Leymus chinensis silage fermentation.

    PubMed

    Zhang, Q; Li, X J; Zhao, M M; Yu, Z

    2014-10-01

    Five LAB strains were evaluated using the acid production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. All five strains (LP1, LP2, LP3, LC1 and LC2) grew at pH 4·0, and LP1 grew at 15°C. Strains LP1, LP2 and LP3 were identified as Lactobacillus plantarum, whereas LC1 and LC2 were classified as Lactobacillus casei by sequencing 16S rDNA. The five isolated strains and two commercial inoculants (PS and CL) were added to native grass and Leymus chinensis (Trin.) Tzvel. for ensiling. All five isolated strains decreased the pH and ammonia nitrogen content, increased the lactic acid content and LP1, LP2 and LP3 increased the acetic content and lactic/acetic acid ratio of L. chinensis silage significantly. The five isolated strains and two commercial inoculants decreased the butyric acid content of the native grass silage. LP2 treatment had lower butyric acid content and ammonia nitrogen content than the other treatments. The five isolated strains improved the quality of L. chinensis silage. The five isolated strains and the two commercial inoculants were not effective in improving the fermentation quality of the native grass silage, but LP2 performed better comparatively. Significance and impact of the study: Leymus chinensis is an important grass in China and Russia, being the primary grass of the short grassland 'steppe' regions of central Asia. However, it has been difficult to make high-quality silage of this species because of low concentration of water-soluble carbohydrates (WSC). Isolating and evaluating lactic acid bacteria strains will be helpful for improving the silage quality of this extensively grown species. PMID:24888497

  2. Complete Genome Sequence of Campylobacter iguaniorum Strain RM11343, Isolated from an Alpaca

    PubMed Central

    Yee, Emma; Huynh, Stephen; Chapman, Mary H.; Parker, Craig T.

    2016-01-01

    Campylobacter iguaniorum is a member of the C. fetus group of campylobacters and is one of two Campylobacter taxa isolated from reptiles. This study describes the whole-genome sequence of the C. iguaniorum strain RM11343, which was isolated from a California alpaca fecal sample. PMID:27365359

  3. Complete Genome Sequence of Bifidobacterium breve CECT 7263, a Strain Isolated from Human Milk

    PubMed Central

    Jiménez, Esther; Villar-Tajadura, M. Antonia; Marín, María; Fontecha, Javier; Requena, Teresa; Arroyo, Rebeca; Fernández, Leónides

    2012-01-01

    Bifidobacterium breve is an actinobacterium frequently isolated from colonic microbiota of breastfeeding babies. Here, we report the complete and annotated genome sequence of a B. breve strain isolated from human milk, B. breve CECT 7263. The genome sequence will provide new insights into the biology of this potential probiotic organism and will allow the characterization of genes related to beneficial properties. PMID:22740680

  4. Complete Genome Sequence of a Rat Hepatitis E Virus Strain Isolated in the United States

    PubMed Central

    Debing, Yannick; Emerson, Suzanne U.; Purcell, Robert H.; Dallmeier, Kai

    2014-01-01

    Hepatitis E virus is a common cause of acute hepatitis in humans. Related viruses have been isolated from multiple animal species, including rats, but their impact on human health is unclear. We present the first full-length genome sequence of a rat hepatitis E virus strain isolated in the United States (LA-B350). PMID:25377700

  5. Complete genome sequence of the Campylobacter iguaniorum strain RM11343, isolated from an alpaca

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter iguaniorum is a member of the C. fetus group of campylobacters and is one of two Campylobacter taxa isolated from reptiles. This study describes the whole-genome sequence of the C. iguaniorum strain RM11343, which was isolated from a California alpaca fecal sample....

  6. Complete genome sequence of the Campylobacter iguaniorum strain RM11343, isolated from an alpaca.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter iguaniorum is a member of the C. fetus group of campylobacters and is one of two Campylobacter taxa isolated from reptiles. This study describes the whole-genome sequence of the C. iguaniorum strain RM11343, which was isolated from a California alpaca fecal sample....

  7. Complete Genome Sequence of Campylobacter iguaniorum Strain RM11343, Isolated from an Alpaca.

    PubMed

    Miller, William G; Yee, Emma; Huynh, Stephen; Chapman, Mary H; Parker, Craig T

    2016-01-01

    Campylobacter iguaniorum is a member of the C. fetus group of campylobacters and is one of two Campylobacter taxa isolated from reptiles. This study describes the whole-genome sequence of the C. iguaniorum strain RM11343, which was isolated from a California alpaca fecal sample. PMID:27365359

  8. Emergence of high level azithromycin-resistant Neisseria gonorrhoeae strain isolated in Argentina.

    PubMed

    Galarza, Patricia G; Alcalá, Belén; Salcedo, Celia; Canigia, Liliana Fernández; Buscemi, Luis; Pagano, Irene; Oviedo, Claudia; Vázquez, Julio A

    2009-12-01

    One Neisseria gonorrhoeae strains highly resistant to azithromycin AzHLR (MIC >2048 mg/L) was isolated in Argentina in 2001 and it has been characterized by N. gonorrhoeae multiantigen sequence typing (NG-MAST) as ST696, suggesting a different event to other isolates in Europe. Neither, mtrR mutations or presence of mef gene were detected.

  9. Phenotypic, antigenic, and molecular characterization of Pasteurella piscicida strains isolated from fish.

    PubMed Central

    Magariños, B; Romalde, J L; Bandín, I; Fouz, B; Toranzo, A E

    1992-01-01

    We compared Pasteurella piscicida strains isolated from different fish species in several European countries with strains isolated in Japan and the United States. The taxonomic analysis revealed that, regardless of the geographic origin and source of isolation, all the strains exhibited the same biochemical and physiological characteristics. Serological assays with different rabbit antisera demonstrated a high level of antigenic similarity among strains, with cross-agglutination titers of 20,480 to 40,960. This serological homogeneity was supported by the lipopolysaccharide (LPS) and membrane protein profiles. All the P. piscicida strains had the same electrophoretic LPS pattern, showing O side chains with a ladder-like structure, and shared at least four major outer membrane proteins, of 20, 30, 42, and 53 kDa. Western blot (immunoblot) analysis with LPS and protein indicated that all the P. piscicida strains are immunologically related. In addition, the chromosomal DNA fingerprint patterns obtained for the European strains with the enzymes EcoRI and BamHI were practically identical to those of the Japanese and U.S. strains. Although some differences were found in the plasmid profiles of P. piscicida, a large number of strains possessed in common plasmid bands of 20 and 7 MDa. In addition, a plasmid of 50 MDa was present in the majority of the European strains. Restriction endonuclease analysis demonstrated the genetic homology of the plasmid bands shared by most of the European strains. All the P. piscicida strains had the same drug resistance patterns, indicating that a correlation between plasmid carriage and resistance to a specific antimicrobial agent cannot be established. The high levels of phenotypic, serological, and genetic homogeneity found among the P. piscicida strains should facilitate the development of DNA probes with diagnostic purposes as well as the design of effective vaccines. Images PMID:1444366

  10. Identification of a cyprinid fish, the tench Tinca tinca L., as a carrier of the bacterium Aeromonas salmonicida, causative agent of furunculosis in salmonids.

    PubMed

    Bernoth, E M; Körting, W

    1992-10-01

    A typical, pigment-producing strain of Aeromonas salmonicida (A. sal.), the causative agent of furunculosis in salmonid fish species, was isolated from a cyprinid species, the tench Tinca tinca L. with papilloma-like skin alterations. Histopathology of the papilloma-like skin alterations in tench revealed "round holes", distinctly lined by thick layers of epithelial cells, but no bacteria. The organism was isolated from skin, gills and fins, but not internal organs. The isolate proved highly virulent for both juvenile tench and brown trout Salmo trutta L. in experimental infection, but it did not reproduce the clinical picture. The causative role of A. sal. for the surface lesions remains questionable. However, there is a perceived risk of the organism's transmission between tench and other susceptible species of fish, especially farmed trout. PMID:1462724

  11. Biological control of Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) using Aeromonas phage PAS-1.

    PubMed

    Kim, J H; Choresca, C H; Shin, S P; Han, J E; Jun, J W; Park, S C

    2015-02-01

    The potential control efficacy of Aeromonas phage PAS-1 was evaluated against Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) model in this study. The phage was co-cultured with the virulent A. salmonicida subsp. salmonicida strain AS05 that possesses the type III secretion system (TTSS) ascV gene, and efficient bacteriolytic activity was observed against the bacteria. The administration of PAS-1 in rainbow trout demonstrated that the phage was cleared from the fish within 200 h post-administration, and a temporal neutralizing activity against the phage was detected in the sera of phage-administrated fish. The administration of PAS-1 (multiplicity of infection: 10 000) in A. salmonicida subsp. salmonicida infected rainbow trout model showed notable protective effects, with increased survival rates and mean times to death. These results demonstrated that Aeromonas phage PAS-1 could be considered as an alternative biological control agent against A. salmonicida subsp. salmonicida infections in rainbow trout culture.

  12. Isolation of Dickeya dadantii strains from potato disease and biocontrol by their bacteriophages

    PubMed Central

    Soleimani-Delfan, Abbas; Etemadifar, Zahra; Emtiazi, Giti; Bouzari, Majid

    2015-01-01

    One of the most economically important bacterial pathogens of plants and plant products is Dickeya dadantii. This bacterium causes soft rot disease in tubers and other parts of the potato and other plants of the Solanaceae family. The application of restricted host range bacteriophages as biocontrol agents has recently gained widespread interest. This study purposed to isolate the infectious agent of the potato and evaluate its biocontrol by bacteriophages. Two phytopathogenic strains were isolated from infected potatoes, identified based on biochemical and 16S rRNA gene sequencing, and submitted to GenBank as D. dadantii strain pis3 (accession no. HQ423668) and D. dadantii strain sip4 (accession no. HQ423669). Their bacteriophages were isolated from Caspian Sea water by enriching the water filtrate with D. dadantii strains as hosts using spot or overlay methods. On the basis of morphotypes, the isolated bacteriophages were identified as members of the Myoviridae and Siphoviridae families and could inhibit the growth of antibiotic resistant D. dadantii strains in culture medium. Moreover, in Dickeya infected plants treated with bacteriophage, no disease progression was detected. No significant difference was seen between phage-treated and control plants. Thus, isolated bacteriophages can be suggested for the biocontrol of plant disease caused by Dickeya strains. PMID:26413062

  13. Isolation of Dickeya dadantii strains from potato disease and biocontrol by their bacteriophages.

    PubMed

    Soleimani-Delfan, Abbas; Etemadifar, Zahra; Emtiazi, Giti; Bouzari, Majid

    2015-01-01

    One of the most economically important bacterial pathogens of plants and plant products is Dickeya dadantii. This bacterium causes soft rot disease in tubers and other parts of the potato and other plants of the Solanaceae family. The application of restricted host range bacteriophages as biocontrol agents has recently gained widespread interest. This study purposed to isolate the infectious agent of the potato and evaluate its biocontrol by bacteriophages. Two phytopathogenic strains were isolated from infected potatoes, identified based on biochemical and 16S rRNA gene sequencing, and submitted to GenBank as D. dadantii strain pis3 (accession no. HQ423668) and D. dadantii strain sip4 (accession no. HQ423669). Their bacteriophages were isolated from Caspian Sea water by enriching the water filtrate with D. dadantii strains as hosts using spot or overlay methods. On the basis of morphotypes, the isolated bacteriophages were identified as members of the Myoviridae and Siphoviridae families and could inhibit the growth of antibiotic resistant D. dadantii strains in culture medium. Moreover, in Dickeya infected plants treated with bacteriophage, no disease progression was detected. No significant difference was seen between phage-treated and control plants. Thus, isolated bacteriophages can be suggested for the biocontrol of plant disease caused by Dickeya strains.

  14. Novel insights into the pathogenicity of epidemic Aeromonas hydrophila ST251 clones from comparative genomics

    PubMed Central

    Pang, Maoda; Jiang, Jingwei; Xie, Xing; Wu, Yafeng; Dong, Yuhao; Kwok, Amy H. Y.; Zhang, Wei; Yao, Huochun; Lu, Chengping; Leung, Frederick C.; Liu, Yongjie

    2015-01-01

    Outbreaks in fish of motile Aeromonad septicemia (MAS) caused by Aeromonas hydrophila have caused a great concern worldwide. Here, for the first time, we provide two complete genomes of epidemic A. hydrophila strains isolated in China. To gain an insight into the pathogenicity of epidemic A. hydrophila, we performed comparative genomic analyses of five epidemic strains belonging to sequence type (ST) 251, together with the environmental strain ATCC 7966T. We found that the known virulence factors, including a type III secretion system, a type VI secretion system and lateral flagella, are not required for the high virulence of the ST251 clonal group. Additionally, our work identifies three utilization pathways for myo-inositol, sialic acid and L-fucose providing clues regarding the factors that underlie the epidemic and virulent nature of ST251 A. hydrophila. Based on the geographical distribution and biological resources of the ST251 clonal group, we conclude that ST251 is a high-risk clonal group of A. hydrophila which may be responsible for the MAS outbreaks in China and the southeastern United States. PMID:26014286

  15. Beta-lactamase-free penicillin amidase from Alcaligenes sp.: isolation strategy, strain characteristics, and enzyme immobilization.

    PubMed

    Pal, A; Samanta, T B

    1999-11-01

    Isolation and characterization of a beta-lactamase (EC 3.5.2.6)-free, penicillin amidase (penicillin amidohydrolase, EC 3.5.1. 11)-producing organism is reported. The test strain was isolated by an enrichment technique with a substrate other than penicillins. The isolated strain belongs to the genus Alcaligenes. Phenylacetic acid was found to be the inducer of penicillin amidase. The amidase has a broad substrate spectrum. It is very active against penicillin G and semisynthetic cephalosporins, whereas penicillin V and semisynthetic penicillins acted moderately as a substrate. Immobilized cells of Alcaligenes sp. were shown to act as a reversible enzyme. PMID:10489431

  16. [Isolation and characterization of wild Sporothrix schenkii strains and investigation of sporototrichin reactors].

    PubMed

    Sánchez-Alemán, Miguel Angel; Araiza, Javier; Bonifaz, Alexandro

    2004-01-01

    We conducted a study in the southern mountains of the Mexican State of Oaxaca that consisted of isolation of wild Sporothrix schenckii strains obtained from soil samples and investigation of positive reactors to skin test reaction with sprotrichin antigen. The study was conducted by means of recollection of soil samples and processing of these with dilution methods and fungal isolation in ordinary culture media Sabouraud simple Agar with and without antibiotics (SS, SA). Suspected strains underwent dimorphism, melanin formation, and virulence confirmation tests. Investigation of positive reactors to sporotrichin Y (yeast) was also conducted. Three supposed strains were identified due to their reproductive characteristics, melanin production, and virulence. In the community, 144 individuals were studied, of whom 6.25% were positive to sporotichin. Isolation of virulent strains of Sporothrix schenkii from nature (soil) and primoinfection of a percentage of the studied population were confirmed.

  17. Diversity of Geotrichum candidum Strains Isolated from Traditional Cheesemaking Fabrications in France

    PubMed Central

    Marcellino, N.; Beuvier, E.; Grappin, R.; Guéguen, M.; Benson, D. R.

    2001-01-01

    The diversity of French fungus-ripened cheeses is due partly to the succession of fungi that colonize the cheese during ripening. Geotrichum candidum appears in the early stages of ripening on soft cheeses such as Camembert and semihard cheeses such as St. Nectaire and Reblochon. Its lipases and proteases promote flavor development, and its aminopeptidases reduce bitterness imparted by low-molecular-weight peptides in cheese. We assessed the genetic diversity of G. candidum strains by using random amplification of polymorphic DNA (RAPD)-PCR correlated with phenotypic tests for carbon assimilation and salt tolerance. Strains were isolated from milk, curd, and cheese collected in seven major cheesemaking regions of France. Sixty-four isolates were characterized. We found high genetic diversity of G. candidum even within the same cheesemaking regions. Strains did not group according to region. All of the strains from the Haute-Savoie were able to assimilate lactate as the sole source of carbon, while lactate assimilation varied among strains from the Auvergne. Strains varied in d-mannitol assimilation, and none used citrate as the sole source of carbon. Yeast-like colony morphology predominated in Reblochon, while all of the strains isolated from St. Nectaire were filamentous. The RAPD-PCR technique readily differentiated Geotrichum fragrans isolated from milk and curd in a St. Nectaire cheesemaking facility. This study reveals an enormous diversity of G. candidum that has been empirically selected through the centuries by the cheesemakers of France. PMID:11571181

  18. Molecular characterisation of quinolone-resistant Shigella strains isolated in Tehran, Iran.

    PubMed

    Ranjbar, Reza; Behnood, Vahid; Memariani, Hamed; Najafi, Ali; Moghbeli, Majid; Mammina, Caterina

    2016-06-01

    Over the past few years, the number of Shigella strains resistant to nalidixic acid has increased and has made the selection of effective antimicrobial therapy more difficult. The purpose of this study was to investigate the molecular mechanism of quinolone resistance in Shigella strains. Shigella strains isolated from 1100 diarrhoeal patients in Tehran, Iran, were assessed for their susceptibility to nalidixic acid prior to PCR-RFLP and sequence analysis of their quinolone resistance genes. Among 73 Shigella strains isolated, 23 (31.5%) were resistant to nalidixic acid. The most common Shigella spp. was Shigella sonnei (54; 74.0%). Of the 23 quinolone-resistant isolates, 4 (17.4%) (including 2 Shigella flexneri, 1 S. sonnei and 1 Shigella boydii) contained the qnrS gene. However, none of the isolates harboured qnrA or qnrB genes. PCR-RFLP analysis of gyrA showed a mutation profile in two nalidixic acid-resistant strains, including one S. sonnei and one S. flexneri. Sequencing of mutant gyrA genes revealed a point mutation at position 83, resulting in the replacement of serine by leucine. In conclusion, molecular mechanisms of resistance to quinolones were identified in 6 of 23 Shigella isolates. Other possible mechanisms of resistance should also be investigated for better characterisation of quinolone-resistant Shigella isolates. PMID:27436462

  19. Molecular characterization of a Class I Newcastle disease virus strain isolated from a pigeon in China.

    PubMed

    Ren, Shanhui; Xie, Xiumei; Wang, Yanping; Tong, Lina; Gao, Xiaolong; Jia, Yanqing; Wang, Haixin; Fan, Mengfei; Zhang, Shuxia; Xiao, Sa; Wang, Xinglong; Yang, Zengqi

    2016-08-01

    Constant monitoring is performed to elucidate the role of natural hosts in the ecology of Newcastle disease virus (NDV). In this study, an NDV strain isolated from an asymptomatic pigeon was sequenced and analysed. Results showed that the full-length genomes of this isolate were 15,198 nucleotides with the gene order of 3'-NP-P-M-F-HN-L-5'. This NDV isolate was lentogenic, with an intracerebral pathogenicity index of 0.00 and a mean time of death more than 148 h. The isolate possessed a motif of -(112)E-R-Q-E-R-L(117)- at the F protein cleavage site. In addition, 7 and 13 amino acid substitutions were identified in the functional domains of fusion protein (F) and haemagglutinin-neuraminidase protein (HN) proteins, respectively. Analysis of the amino acids of neutralizing epitopes of F and HN proteins showed 3 and 10 amino acid substitutions, respectively, in the isolate. Phylogenetic analysis classified the isolate into genotype Ib in Class I. This isolate shared high homologies with the NDV strains isolated from wild birds and waterfowl in southern and eastern parts of China from 2005 to 2013. To our knowledge, this study is the first to report a NDV strain isolated from pigeon that belongs to genotype Ib in Class I, rather than to the traditional genotype VI or other sub-genotypes in Class II. This study provides information to elucidate the distribution and evolution of Class I viruses for further NDV prevention.

  20. Isolation and characterization of a Bacillus strain capable of degrading the extracellular glucan from Cellulomonas flavigena strain KU.

    PubMed

    Bertram, P A; Buller, C S; Stewart, G C; Akagi, J M

    1993-04-01

    Bacteria capable of utilizing the water-insoluble purified extracellular (1-->3)-beta-D-glucan (curdlan) from Cellulomonas flavigena strain KU by extracellular enzymes, were isolated and characterized. Enrichment cultures from a Winogradsky column were incubated anaerobically at 55 degrees C with curdlan as the sole source of carbon. Colonies surrounded by zones of clearing were selected from subcultures on solid curdlan media. One of the isolates was chosen for further study and identified by conventional methods, API-tests with calculation of similarity coefficients and ID-scores, estimation of mol% (G+C) and DNA-DNA liquid hybridization. The isolate is a facultatively anaerobic, facultatively thermophilic Bacillus sp. Identification at the species-level was not achieved. The isolate was characterized by some rare traits among bacilli, but it remains unresolved whether it defines a new taxon.

  1. Molecular typing of Leptospira spp. strains isolated from field mice confirms a link to human leptospirosis.

    PubMed

    Li, S J; Wang, D M; Zhang, C C; Li, X W; Yang, H M; Tian, K C; Wei, X Y; Liu, Y; Tang, G P; Jiang, X G; Yan, J

    2013-11-01

    In recent years, human leptospirosis has been reported in Jinping and Liping counties, Guizhou province, but the leptospires have never been isolated. To track the source of infection and understand the aetiological characteristics, we performed surveillance for field mice carriage of leptospirosis in 2011. Four strains of leptospire were isolated from Apodemus agrarius. PCR confirmed the four isolates as pathogenic. Multiple-locus variable-number tandem repeat analysis (MLVA) showed that the four strains were closely related to serovar Lai strain 56601 belonging to serogroup Icterohaemorrhagiae, which is consistent with the antibody detection results from local patients. Furthermore, the diversity of leptospiral isolates from different hosts and regions was demonstrated with MLVA. Our results suggest that A. agrarius may be the main carrier of Leptospira in Jinping and Liping counties, and the serogroup Icterohaemorrhagiae serovar may be the epidemic serogroup of Leptospira. This will contribute to the control and prevention of leptospirosis in these localities. PMID:23406882

  2. [Isolation and characteristics of Panax ginseng autotoxin-degrading bacterial strains].

    PubMed

    Zhao, Dong-Yue; Li, Yong; Ding, Wan-Long

    2013-06-01

    In this study, traditional plate culturing method was used to isolate autotoxin-degrading microbial strains, and which were then identified by 16S rDNA homological analysis and morphological characteristics. Furthermore, the growth and autotoxin-degrading efficiency of them were analyzed by liquid culturing method and GC-MS to illustrate their autotoxin-degradation characteristics. As a result, five bacterial strains having autotoxin-degrading activity were isolated from 6-years ginseng nonrhizospheric soil successfully, and which can growth successfully by taking autotoxins added artificially as carbon source in liquid culturing condition. Results indicated that it was feasible to isolate autotoxin-degrading bacteria from ginseng nonrhizospheric soil, and the isolated bacterial strains can be used to degrade autotoxins in soils once planted Panax ginseng.

  3. Isolation and characterization of a Neisseria strain from the liver of a Chinese Peking duck.

    PubMed

    Wang, Hanqing; Chen, Zongyan; Wang, Xiaoxu; Li, Ning; Wei, Jianzhong; Sun, Pei; Wang, Guijun; Liu, Guangqing

    2014-07-01

    A Neisseria strain, Neisseria sp. AH-N10, was isolated from liver of a Chinese Peking duck and characterized using a number of phenotypic and genotypic approaches. Based on scanning electron microscopy examination, the isolated strain has the typical structure of Neisseria species. Sequence comparison of 16S rRNA gene and phylogenetic analysis suggest that Neisseria sp. AH-N10 is closely related to Neisseria canis, which was previously isolated from a human dog bite wound. Animal infection experiments demonstrated that the isolated Neisseria sp. AH-N10 is pathogenic in ducks and mice. The pathogenicity to humans and evolutional origin of this Neisseria strain should be further investigated.

  4. Characterization of Erysipelothrix rhusiopathiae strains isolated from acute swine erysipelas outbreaks in Eastern China.

    PubMed

    Zou, Yao; Zhu, Xiaoming; Muhammad, Hassan Mushtaq; Jiang, Ping; Li, Yufeng

    2015-06-01

    Recently, a series of acute swine erysipelas outbreaks occurred in Eastern China. Eight strains isolated from cases of septicemia were determined as serotype 1a, and 4 of the isolates were resistant to acriflavine. One isolate strain named HX130709 was attenuated on agar media containing acriflavine dye. The 432-bp hypervariable region in spaA gene of the field and attenuated strains were amplified and sequenced. It was further compared with the vaccine strain G4T10, and thus, the eight field strains can be divided into four spaA-types. The partial spaA gene analysis also showed that no point mutations occurred among different archived passages of HX130709 during the attenuation. Results of pulsed-field gel electrophoresis showed that eight distinct patterns with 22 to 30 DNA fragment bands were produced from field strains, and twelve distinct patterns with 23 to 27 DNA fragment bands were produced from different passages of the attenuated strains. Mouse pathogenicity test showed that the mortality of the mice infected with 10(4) CFU field strains was 100% and the attenuation of strain HX130709 occurred between 46 and 50 passages. All the field and attenuated strains were highly sensitive to β-lactam antibiotics, tetracyclines and macrolides. So, we can make conclusions that the acute swine erysipelas outbreaks in Eastern China were caused by serotype 1a E. rhusiopathiae strains with different biochemical characteristics, and the virulence of serotype 1a E. rhusiopathiae strains is unrelated with some point mutations in 432-bp hypervariable region of the spaA gene.

  5. Characterization of Erysipelothrix rhusiopathiae strains isolated from acute swine erysipelas outbreaks in Eastern China

    PubMed Central

    ZOU, Yao; ZHU, Xiaoming; MUHAMMAD, Hassan Mushtaq; JIANG, Ping; LI, Yufeng

    2015-01-01

    Recently, a series of acute swine erysipelas outbreaks occurred in Eastern China. Eight strains isolated from cases of septicemia were determined as serotype 1a, and 4 of the isolates were resistant to acriflavine. One isolate strain named HX130709 was attenuated on agar media containing acriflavine dye. The 432-bp hypervariable region in spaA gene of the field and attenuated strains were amplified and sequenced. It was further compared with the vaccine strain G4T10, and thus, the eight field strains can be divided into four spaA-types. The partial spaA gene analysis also showed that no point mutations occurred among different archived passages of HX130709 during the attenuation. Results of pulsed-field gel electrophoresis showed that eight distinct patterns with 22 to 30 DNA fragment bands were produced from field strains, and twelve distinct patterns with 23 to 27 DNA fragment bands were produced from different passages of the attenuated strains. Mouse pathogenicity test showed that the mortality of the mice infected with 104 CFU field strains was 100% and the attenuation of strain HX130709 occurred between 46 and 50 passages. All the field and attenuated strains were highly sensitive to β-lactam antibiotics, tetracyclines and macrolides. So, we can make conclusions that the acute swine erysipelas outbreaks in Eastern China were caused by serotype 1a E. rhusiopathiae strains with different biochemical characteristics, and the virulence of serotype 1a E. rhusiopathiae strains is unrelated with some point mutations in 432-bp hypervariable region of the spaA gene. PMID:25649849

  6. Isolation of Rhodococcus sp. Strain ECU0066, a New Sulfide Monooxygenase-Producing Strain for Asymmetric Sulfoxidation▿ †

    PubMed Central

    Li, Ai-Tao; Zhang, Jian-Dong; Xu, Jian-He; Lu, Wen-Ya; Lin, Guo-Qiang

    2009-01-01

    A new and efficient sulfide monooxygenase-producing strain, ECU0066, was isolated and identified as a Rhodococcus sp. that could transform phenylmethyl sulfide (PMS) to (S)-sulfoxide with 99% enantiomeric excess via two steps of enantioselective oxidations. Its enzyme activity could be effectively induced by adding PMS or phenylmethyl sulfoxide (PMSO) directly to a rich medium at the early log phase (6 h) of fermentation, resulting in over 10-times-higher production of the enzyme. This bacterial strain also displayed fairly good activity and enantioselectivity toward seven other sulfides, indicating a good potential for practical application in asymmetric synthesis of chiral sulfoxides. PMID:18836022

  7. Draft Genome Sequences of Mycobacterium setense Type Strain DSM-45070 and the Nonpathogenic Strain Manresensis, Isolated from the Bank of the Cardener River in Manresa, Catalonia, Spain

    PubMed Central

    Vilaplana, Cristina; Velasco, Juan; Pluvinet, Raquel; Santín, Sheila; Prat, Cristina; Julián, Esther; Alcaide, Fernando; Comas, Iñaki; Sumoy, Lauro; Cardona, Pere-Joan

    2015-01-01

    We present here the draft genome sequences of two Mycobacterium setense strains. One of them corresponds to the M. setense type strain DSM-45070, originally isolated from a patient with a posttraumatic chronic skin abscess. The other one corresponds to the nonpathogenic M. setense strain Manresensis, isolated from the Cardener River crossing Manresa, Catalonia, Spain. A comparative genomic analysis shows a smaller genome size and fewer genes in M. setense strain Manresensis relative to those of the type strain, and it shows the genome segments unique to each strain. PMID:25657273

  8. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

    PubMed Central

    Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

    2015-01-01

    Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons. PMID:26339653

  9. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater.

    PubMed

    Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

    2015-01-01

    Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons.

  10. High-frequency rugose exopolysaccharide production by Vibrio cholerae strains isolated in Haiti.

    PubMed

    Rahman, Mustafizur; Jubair, Mohammad; Alam, Meer T; Weppelmann, Thomas A; Azarian, Taj; Salemi, Marco; Sakharuk, Ilya A; Rashid, Mohammed H; Johnson, Judith A; Yasmin, Mahmuda; Morris, J Glenn; Ali, Afsar

    2014-01-01

    In October, 2010, epidemic cholera was reported for the first time in Haiti in over 100 years. Establishment of cholera endemicity in Haiti will be dependent in large part on the continued presence of toxigenic V. cholerae O1 in aquatic reservoirs. The rugose phenotype of V. cholerae, characterized by exopolysaccharide production that confers resistance to environmental stress, is a potential contributor to environmental persistence. Using a microbiologic medium promoting high-frequency conversion of smooth to rugose (S-R) phenotype, 80 (46.5%) of 172 V. cholerae strains isolated from clinical and environmental sources in Haiti were able to convert to a rugose phenotype. Toxigenic V. cholerae O1 strains isolated at the beginning of the epidemic (2010) were significantly less likely to shift to a rugose phenotype than clinical strains isolated in 2012/2013, or environmental strains. Frequency of rugose conversion was influenced by incubation temperature and time. Appearance of the biofilm produced by a Haitian clinical rugose strain (altered biotype El Tor HC16R) differed from that of a typical El Tor rugose strain (N16961R) by confocal microscopy. On whole-genome SNP analysis, there was no phylogenetic clustering of strains showing an ability to shift to a rugose phenotype. Our data confirm the ability of Haitian clinical (and environmental) strains to shift to a protective rugose phenotype, and suggest that factors such as temperature influence the frequency of transition to this phenotype.

  11. Unexpected detection of animal VP7 genes among common rotavirus strains isolated from children in Mexico.

    PubMed

    Laird, A R; Ibarra, V; Ruiz-Palacios, G; Guerrero, M L; Glass, R I; Gentsch, J R

    2003-09-01

    In the course of characterizing 103 rotaviruses from children in Mexico, we found that the majority of strains were globally common types (55.4% of total), while uncommon types represented 5.7%, mixed infections with common types represented 14.8%, and partially or fully nontypeable isolates represented about 24%. Serotype G9 was detected for the first time in Mexico. We sequenced a subset of strains that were G nontypeable by reverse transcriptase PCR and found surprisingly that two strains having common human rotavirus P genotypes (8 and 6) had serotype G3 and G4 VP7 gene sequences that shared closer homology with canine and porcine strains, respectively, than with human strains, suggesting that these isolates represented reassortants between human and animal rotaviruses.

  12. Unexpected detection of animal VP7 genes among common rotavirus strains isolated from children in Mexico.

    PubMed

    Laird, A R; Ibarra, V; Ruiz-Palacios, G; Guerrero, M L; Glass, R I; Gentsch, J R

    2003-09-01

    In the course of characterizing 103 rotaviruses from children in Mexico, we found that the majority of strains were globally common types (55.4% of total), while uncommon types represented 5.7%, mixed infections with common types represented 14.8%, and partially or fully nontypeable isolates represented about 24%. Serotype G9 was detected for the first time in Mexico. We sequenced a subset of strains that were G nontypeable by reverse transcriptase PCR and found surprisingly that two strains having common human rotavirus P genotypes (8 and 6) had serotype G3 and G4 VP7 gene sequences that shared closer homology with canine and porcine strains, respectively, than with human strains, suggesting that these isolates represented reassortants between human and animal rotaviruses. PMID:12958276

  13. Aeromonas presence in drinking water from collective reservoirs and wells in peri-urban area in Brazil.

    PubMed

    Pepe Razzolini, Maria Tereza; Risso Günther, Wanda Maria; Martone-Rocha, Solange; Duarte de Luca, Heloísa; Alves Cardoso, Maria Regina

    2010-07-01

    Aeromonas genus is considered an emerging pathogen and its presence in drinking water supplies is a reason to public health concern. This study investigated the occurrence of Aeromonas in samples from collective reservoirs and wells used as drinking water sources in a peri-urban area. A total of 35 water samples were collected from collective reservoirs and 32 from wells bimonthly, from September 2007 to September 2008. Aeromonas spp determination was carried out using a Multiple-Tube Technique. Samples were inoculated into alkaline peptone water and the superficial film formed was transferred to blood agar plates amended with ampicillin. Typical Aeromonas colonies were submitted to a biochemical screening and then to biochemical tests for species differentiation. Aeromonas was detected in 13 (19%) of the 69 samples examined (6 from collective reservoirs and 7 from wells). Concentrations of Aeromonas in collective reservoirs ranged from <0.3 to 1.2 x10(2)MPN/100mL and, in wells, from <0.3 to 2.4 x10(2)MPN/100mL. The most frequent specie in the collective reservoir samples was Aeromonas spp (68%), followed by A. encheleia (14%) and A. allosaccharophila (8%) and A. hydrophila (8%). Aeromonas spp (87%) was the most frequent specie isolated from well samples, followed by A. allosacchariphila (8%), A. encheleia (2%) and A. jandaei (5%). These data show the presence and diversity of Aeromonas genus in the samples analyzed and highlight that its presence in drinking water poses a significant public health concern.

  14. Phylogeny of bacteria isolated from Rhabditis sp. (Nematoda) and identification of novel entomopathogenic Serratia marcescens strains.

    PubMed

    Tambong, James T

    2013-02-01

    Twenty-five bacterial strains isolated from entomopathogenic nematodes were characterized to the genus level by 16S rRNA phylogeny and BLAST analyses. Bacteria strains isolated could be affiliated with seven genera. Microbacterium-like isolates phylogenetically affiliated with M. oxydans while those of Serratia were highly similar to S. marcescens. 16S rRNA sequences of Bacillus isolates matched those of both B. mycoides and B. weihenstephanesis. One isolate each matched Pseudomonas mosselii, Rheinheimera aquimaris, Achromobacter marplatensis, or Staphylococcus hominis. Serratia isolates were examined further for their pathogenicity to Galleria mellonella larvae. All the Serratia isolates exhibited potent pathogenicity toward G. mellonella larvae and possessed a metalloprotease gene encoding for a novel serralysin-like protein. The nucleotide sequence of the metalloprotease gene had 60 synonymous and 8 nonsynonymous substitutions when compared to the closest genBank entry, S. marcescens E-15, with an insertion of a new aspartic acid residue. Tajima's test for equality of evolutionary rate was significant between the metalloprotease gene sequence of S. marcescens strain DOAB 216-82 (this study) and strain E-15. This new insecticidal metalloprotease gene and/or its product could have applications in agricultural biotechnology.

  15. Full Genome Sequence of Egg Drop Syndrome Virus Strain FJ12025 Isolated from Muscovy Duckling.

    PubMed

    Fu, Guanghua; Chen, Hongmei; Huang, Yu; Cheng, Longfei; Fu, Qiuling; Shi, Shaohua; Wan, Chunhe; Chen, Cuiteng; Lin, Jiansheng

    2013-01-01

    Egg drop syndrome virus (EDSV) strain FJ12025 was isolated from a 9-day-old Muscovy duckling. The results of the sequence showed that the genome of strain FJ12025 is 33,213 bp in length, with a G+C content of 43.03%. When comparing the genome sequence of strain FJ12025 to that of laying duck original strain AV-127, we found 50 single-nucleotide polymorphisms (SNPs) between the two viral genome sequences. A genomic sequence comparison of FJ12025 and AV-127 will help to understand the phenotypic differences between the two viruses. PMID:23969050

  16. Isolation and characterization of a new strain of lymphocytic choriomeningitis virus from rodents in southwestern France.

    PubMed

    Yama, Ines N; Cazaux, Benoite; Britton-Davidian, Janice; Moureau, Grégory; Thirion, Laurence; de Lamballerie, Xavier; Dobigny, Gauthier; Charrel, Rémi N

    2012-10-01

    A total of 821 tissue samples from rodents trapped during field campaigns organized in Europe and Africa were screened for the presence of arenaviruses by molecular methods and cell culture inoculation when feasible. Two Mus musculus domesticus trapped in the southwestern part of France were infected with a potentially new strain of lymphocytic choriomeningitis virus (LCMV), here referred to as LCMV strain HP65-2009, which was isolated and genetically characterized by whole genome sequencing. Genetic and phylogenetic analyses comparing LCMV HP65-2009 with 26 other LCMV strains showed that it represents a novel highly-divergent strain within the group of Mus musculus-associated LCMV.

  17. Plasmid Profiles of Virulent Rhodococcus equi Strains Isolated from Infected Foals in Poland.

    PubMed

    Kalinowski, Marcin; Grądzki, Zbigniew; Jarosz, Łukasz; Kato, Kiyoko; Hieda, Yu; Kakuda, Tsutomu; Takai, Shinji

    2016-01-01

    Rhodococcus equi is an important bacterial pathogen in foals up to 6 months old, widespread in horse farms all over the world. It was found that only virulent R. equi strains expressing 15-17 kDa virulence-associated protein (VapA) and having large virulence plasmid of 85-90 kb containing vapA gene are pathogenic for horses. To date, 12 plasmid types have been reported in VapA positive strains from horses. There are no data concerning plasmid types of Polish field R. equi strains isolated from horses and horse farm environment. The aim of the study is to determine plasmid profiles of virulent R. equi strains isolated in Poland from dead foals as well as from soil samples taken from horse breeding farms. Plasmid profiles of 10 clinical strains derived from 8 farms and 11 environmental strains from 3 farms, confirmed as virulent by PCR, were compared with 12 reference strains containing the known plasmid size and type. Plasmid DNAs were analysed by digestion with the restriction endonucleases BamHI, EcoRI, EcoT22I, and HindIII for detailed comparison and estimation of plasmid sizes. The results of RFLP analysis revealed that all except one isolates used in the study are classified as VapA 85 kb type I plasmid. One strain harboured VapA 87 kb type I plasmid. This is the first report of plasmid types of Polish field R. equi strains. The results of our preliminary investigations on horse farms located in central and eastern Poland indicate that the virulent R. equi strains thus far isolated from diseased foals and horse farms environment represent a highly uniform plasmid pattern. PMID:27074033

  18. Plasmid Profiles of Virulent Rhodococcus equi Strains Isolated from Infected Foals in Poland

    PubMed Central

    Kalinowski, Marcin; Grądzki, Zbigniew; Jarosz, Łukasz; Kato, Kiyoko; Hieda, Yu; Kakuda, Tsutomu; Takai, Shinji

    2016-01-01

    Rhodococcus equi is an important bacterial pathogen in foals up to 6 months old, widespread in horse farms all over the world. It was found that only virulent R. equi strains expressing 15–17 kDa virulence-associated protein (VapA) and having large virulence plasmid of 85–90 kb containing vapA gene are pathogenic for horses. To date, 12 plasmid types have been reported in VapA positive strains from horses. There are no data concerning plasmid types of Polish field R. equi strains isolated from horses and horse farm environment. The aim of the study is to determine plasmid profiles of virulent R. equi strains isolated in Poland from dead foals as well as from soil samples taken from horse breeding farms. Plasmid profiles of 10 clinical strains derived from 8 farms and 11 environmental strains from 3 farms, confirmed as virulent by PCR, were compared with 12 reference strains containing the known plasmid size and type. Plasmid DNAs were analysed by digestion with the restriction endonucleases BamHI, EcoRI, EcoT22I, and HindIII for detailed comparison and estimation of plasmid sizes. The results of RFLP analysis revealed that all except one isolates used in the study are classified as VapA 85 kb type I plasmid. One strain harboured VapA 87 kb type I plasmid. This is the first report of plasmid types of Polish field R. equi strains. The results of our preliminary investigations on horse farms located in central and eastern Poland indicate that the virulent R. equi strains thus far isolated from diseased foals and horse farms environment represent a highly uniform plasmid pattern. PMID:27074033

  19. Chemical modification of polyvinyl chloride and silicone elastomer in inhibiting adhesion of Aeromonas hydrophila.

    PubMed

    Kregiel, Dorota; Berlowska, Joanna; Mizerska, Urszula; Fortuniak, Witold; Chojnowski, Julian; Ambroziak, Wojciech

    2013-07-01

    Disease-causing bacteria of the genus Aeromonas are able to adhere to pipe materials, colonizing the surfaces and forming biofilms in water distribution systems. The aim of our research was to study how the modification of materials used commonly in the water industry can reduce bacterial cell attachment. Polyvinyl chloride and silicone elastomer surfaces were activated and modified with reactive organo-silanes by coupling or co-crosslinking silanes with the native material. Both the native and modified surfaces were tested using the bacterial strain Aeromonas hydrophila, which was isolated from the Polish water distribution system. The surface tension of both the native and modified surfaces was measured. To determine cell viability and bacterial adhesion two methods were used, namely plate count and luminometry. Results were expressed in colony-forming units (c.f.u.) and in relative light units (RLU) per cm(2). Almost all the chemically modified surfaces exhibited higher anti-adhesive and anti-microbial properties in comparison to the native surfaces. Among the modifying agents examined, poly[dimethylsiloxane-co-(N,N-dimethyl-N-n-octylammoniopropyl chloride) methylsiloxane)] terminated with hydroxydimethylsilyl groups (20 %) in silicone elastomer gave the most desirable results. The surface tension of this modifier, was comparable to the non-polar native surface. However, almost half of this value was due to the result of polar forces. In this case, in an adhesion analysis, only 1 RLU cm(-2) and less than 1 c.f.u. cm(-2) were noted. For the native gumosil, the results were 9,375 RLU cm(-2) and 2.5 × 10(8) c.f.u. cm(-2), respectively. The antibacterial activity of active organo-silanes was associated only with the carrier surface because no antibacterial compounds were detected in liquid culture media, in concentrations that were able to inhibit cell growth.

  20. Protection of ornamental gold fish Carassius auratus against Aeromonas hydrophila by treating Ixora coccinea active principles.

    PubMed

    Anusha, Paulraj; Thangaviji, Vijayaragavan; Velmurugan, Subramanian; Michaelbabu, Mariavincent; Citarasu, Thavasimuthu

    2014-02-01

    Herbals such as Ixora coccinea, Daemia extensa and Tridax procumbens were selected to screen in vitro antibacterial and immunostimulant activity against the freshwater fish pathogen Aeromonas hydrophila using different organic polar and non-polar solvents. Initial screening results revealed that, ethyl acetate extracts and its purified fraction of I. coccinea was able to suppress the A. hydrophila strains at more than 15 mm of zone of inhibition and positive immunostimulant activity. The purified active fraction, which eluted from H40: EA60 mobile phase was structurally characterized by GC-MS analysis. Two compounds such as Diethyl Phthalate (1,2-Benzene dicarboxylic acid, monobutyl ester) and Dibutyl Phthalate were characterized using NIST database search. In order to study the in vivo immunostimulant influence of the compounds, the crude extracts (ICE) and purified fractions (ICF) were incorporated to the artificial diets at the concentration of 400 mg kg⁻¹ and fed to the ornamental gold fish Carassius auratus for 30 days. After termination of feeding experiment, they were challenged with highly virulent A. hydrophila AHV-1 which was isolated from infected gold fish and studied the survival, specific bacterial load reduction, serum biochemistry, haematology, immunology and histological parameters. The control diet fed fishes succumbed to death within five days at 100% mortality whereas ICE and ICF fed groups survived 60 and 80% respectively after 10 days. The diets also helped to decrease the Aeromonas load after challenge and significantly (P ≤ 0.01) improved the serum albumin, globulin and protein. The diets also helped to increase the RBC and haemoglobin level significantly (P ≤ 0.05) from the control group. Surprisingly the immunological parameters like phagocytic activity, serum bactericidal activity and lysozyme activity were significantly increased (P ≤ 0.001) in the experimental diets. Macrophages and erythrocytes were abundantly expressed in the

  1. Chemical modification of polyvinyl chloride and silicone elastomer in inhibiting adhesion of Aeromonas hydrophila.

    PubMed

    Kregiel, Dorota; Berlowska, Joanna; Mizerska, Urszula; Fortuniak, Witold; Chojnowski, Julian; Ambroziak, Wojciech

    2013-07-01

    Disease-causing bacteria of the genus Aeromonas are able to adhere to pipe materials, colonizing the surfaces and forming biofilms in water distribution systems. The aim of our research was to study how the modification of materials used commonly in the water industry can reduce bacterial cell attachment. Polyvinyl chloride and silicone elastomer surfaces were activated and modified with reactive organo-silanes by coupling or co-crosslinking silanes with the native material. Both the native and modified surfaces were tested using the bacterial strain Aeromonas hydrophila, which was isolated from the Polish water distribution system. The surface tension of both the native and modified surfaces was measured. To determine cell viability and bacterial adhesion two methods were used, namely plate count and luminometry. Results were expressed in colony-forming units (c.f.u.) and in relative light units (RLU) per cm(2). Almost all the chemically modified surfaces exhibited higher anti-adhesive and anti-microbial properties in comparison to the native surfaces. Among the modifying agents examined, poly[dimethylsiloxane-co-(N,N-dimethyl-N-n-octylammoniopropyl chloride) methylsiloxane)] terminated with hydroxydimethylsilyl groups (20 %) in silicone elastomer gave the most desirable results. The surface tension of this modifier, was comparable to the non-polar native surface. However, almost half of this value was due to the result of polar forces. In this case, in an adhesion analysis, only 1 RLU cm(-2) and less than 1 c.f.u. cm(-2) were noted. For the native gumosil, the results were 9,375 RLU cm(-2) and 2.5 × 10(8) c.f.u. cm(-2), respectively. The antibacterial activity of active organo-silanes was associated only with the carrier surface because no antibacterial compounds were detected in liquid culture media, in concentrations that were able to inhibit cell growth. PMID:23397109

  2. Characterization of rumen bacterial strains isolated from enrichments of rumen content in the presence of propolis.

    PubMed

    de Aguiar, Sílvia Cristina; Zeoula, Lucia Maria; do Prado, Odimari Pricila Pires; Arcuri, Pedro Braga; Forano, Evelyne

    2014-11-01

    Propolis presents many biological properties, including antibacterial activities, and has been proposed as an additive in ruminant nutrition. Twenty bacterial strains, previously isolated from enrichments of Brazilian cow rumen contents in the presence of different propolis extracts (LLOS), were characterized using phenotyping and 16S rRNA identification. Seven strains were assigned to Streptococcus sp., most likely S. bovis, and were all degrading starch. One amylolytic lactate-utilizing strain of Selenomonas ruminantium was also found. Two strains of Clostridium bifermentans were identified and showed proteolytic activity. Two strains were assigned to Mitsuokella jalaludinii and were saccharolytic. One strain belonged to a Bacillus species and seven strains were affiliated with Escherichia coli. All of the 20 strains were able to use many sugars, but none of them were able to degrade the polysaccharides carboxymethylcellulose and xylans. The effect of three propolis extracts (LLOS B1, C1 and C3) was tested on the in vitro growth of four representative isolates of S. bovis, E. coli, M. jalaludinii and C. bifermentans. The growth of S. bovis, E. coli and M. jalaludinii was not affected by the three propolis extracts at 1 mg ml(-1). C. bifermentans growth was completely inhibited at this LLOS concentration, but this bacterium was partially resistant at lower concentrations. LLOS C3, with the lower concentration of phenolic compounds, was a little less inhibitory than B1 and C1 on this strain.

  3. Isolation of Rhizobium loti Strain-Specific DNA Sequences by Subtraction Hybridization

    PubMed Central

    Bjourson, A. J.; Cooper, J. E.

    1988-01-01

    Mixed-phase (heterogeneous) and single-phase (homogeneous) DNA subtraction-hybridization methods were used to isolate specific DNA probes for closely related Rhizobium loti strains. In the heterogeneous method, DNA from the prospective probe strain was repeatedly hybridized to a mixture of DNA from cross-hybridizing strains (subtracter DNA) which was immobilized on an epoxy-activated cellulose matrix. Probe strain sequences which shared homology with the matrix-bound subtracter DNA hybridized to it, leaving unique probe strain sequences in the mobile phase. In the homogeneous method, probe strain sequences were hybridized in solution to biotinylated, mercurated subtracter DNA. Biotinylated, mercurated subtracer DNA and probe strain sequences hybridized to it were removed by two-step affinity chromatography on streptavidin-agarose and thiol-Sepharose. The specificity of the sequences remaining after subtraction hybridization by both methods was assessed and compared by colony hybridization with R. loti strains. Both methods allowed the rapid isolation of strain-specific DNA fragments which were suitable for use as probes. Images PMID:16347782

  4. Probiotic features of Lactobacillus strains isolated from Ragusano and Pecorino Siciliano cheeses.

    PubMed

    Caggia, C; De Angelis, M; Pitino, I; Pino, A; Randazzo, C L

    2015-09-01

    In the present study 177 Lactobacillus spp. strains, isolated from Ragusano and Pecorino Siciliano cheeses, were in vitro screened for probiotic traits, and their characteristics were compared to those of Lactobacillus rhamnosus GG, commercial strain. Based on acidic and bile salt resistance, thirteen Lactobacillus strains were selected. The multiplex-PCR application revealed that nine strains belonged to L. rhamnosus species and four to Lactobacillus paracasei species. All selected strains were further investigated for transit tolerance in simulated upper gastrointestinal tract (GI), for adhesion capacity to human intestinal cell lines, for hydrophobicity, for co-aggregation and auto-aggregation and for antimicrobial activities. Moreover, antibiotic resistance, hemolytic and bile salt hydrolase activities were investigated for safety assessment. Viable counts after simulated gastric and duodenal transit revealed that overall the selected lactobacilli tolerated better pancreatic juice and bile salts than acidic juice. In particular, three L. rhamnosus strains (FS10, FS2, and PS11) and one L. paracasei strain (PM8) increased their cell density after the simulated GI transit. The same strains showed also high percentage of auto-aggregation and co-aggregation with Escherichia coli. All strains were effective against both Staphylococcus aureus and E. coli and variability was achieved versus Listeria monocytogenes and Enterococcus faecalis used as pathogenic indicator strains. Different behavior was revealed by strains for adhesion ability and hydrophobicity, which are not always linked each other and are strongly strain-dependent. From the safety point of view, no isolate showed hemolytic and bile salt hydrolase activities, except one, and most of the strains were sensitive to a broad range of clinical antibiotics. This work showed that the L. rhamnosus FS10 and the L. paracasei PM8 are good promising probiotic candidates for further in vivo investigations.

  5. Low virulent oral Candida albicans strains isolated from smokers.

    PubMed

    de Azevedo Izidoro, Ana Claudia Santos; Semprebom, Andressa Marafon; Baboni, Fernanda Brasil; Rosa, Rosimeire Takaki; Machado, Maria Angela Naval; Samaranayake, Lakshman Perera; Rosa, Edvaldo Antonio Ribeiro

    2012-02-01

    It is widely accepted that tabagism is a predisposing factor to oral candidosis and cumulate data suggest that cigarette compounds may increase candidal virulence. To verify if enhanced virulence occurs in Candida albicans from chronic smokers, a cohort of 42 non-smokers and other of 58 smokers (all with excellent oral conditions and without signs of candidosis) were swabbed on tong dorsum and jugal mucosa. Results showed that oral candidal loads do not differ between smoker and non-smokers. Activities of secreted aspartyl-protease (Sap), phospholipase, chondroitinase, esterase-lipase, and haemolysin secretions were screened for thirty-two C. albicans isolates. There were detected significant increments in phospholipasic and chondroitinasic activities in isolates from non-smokers. For other virulence factors, no differences between both cohorts were achieved. PMID:21924704

  6. [Bacteriological study of the strains isolated from ocular infections].

    PubMed

    Hajoui, Fatima-Zahra; Daoudi, Naima; Kabbaj, Hakima; Alaoui, Ahmed; Seffar, Myriam

    2012-01-01

    Isolation of bacteria involved in eye infections and their susceptibility pattern to various antibiotics in vitro eye were studied. Different ocular samples were obtained from 354 patients hospitalized in ophthalmology unit. The samples were inoculated directly onto appropriate culture media. Biochemical tests have been performed and microorganisms were identified according to standard procedure. The in vitro susceptibility of pathogens to antibiotics has been studied as recommended by the CA-SFM; 129 bacteria were isolated with a prevalence rate of 36.4%. The conjunctival swabs were predominant in 70.5% (n=91). In conjunctivitis and keratitis, the main causal agent was coagulase-negative staphylococci followed by alpha hemolytic streptococci. Bacteria from contact lenses were represented mostly by Enterobacteriaceae (50%). In uveitis and cellulite, different bacteria were isolated. The pathogens studied were susceptible to most antibiotics tested except Staphylococcus aureus that showed resistance to penicillin G, Pseudomonas sp expressed an average sensitivity to piperacillin and ticarcillin. The alpha hemolytic streptococci showed very low sensitivity to ciprofloxacin. In conclusion many species could be responsible for eye infections. They were sensitive to most antibiotics tested exceptions. PMID:23207815

  7. Phenotypic and genotypic characterization of Bordetella bronchiseptica strains isolated from pigs in Poland.

    PubMed

    Stepniewska, K; Urbaniak, K; Markowska-Daniel, I

    2014-01-01

    A total of 209 Bordetella bronchiseptica (Bbr) strains isolated from pigs were examined. Phenotypic study included: biochemical characterization (motility, catalase, oxidase, urease activity, nitrate reduction and growth on MacConkey agar) and antimicrobial susceptibility (disc diffusion method). Genotypic studies based on detection of three genes encoded virulence factors, such as: flagella (fla), dermonecrotoxin (dnt), and exogenous ferric siderophore receptor (bfrZ), using PCR. Most of the Bbr strains tested had a homogeneous biochemical profile. 97.6% of them provided suitable results in biochemical tests. All Bbr isolates tested showed high resistance to penicillin (100%), linco-spectin (100%) and ceftiofur (97.9%). Over 57% and 43% of Bbr strains were resistant to ampicillin and amoxicillin, respectively. All Bbr isolates showed high sensitivity to most chemotherapeutics used such as enrofloxacin (97.9%), tetracycline (97.9%), oxytetracycline (97.9%), amoxicillin with clavulonic acid (95.8%), florfenicol (90.4%), and gentamicine (77.6%). Over of 94% of Bbr strains were moderately susceptible to norfloxacine. Molecular analysis confirmed that almost all evaluated Bbr strains (94.7%) possessed the fla gene. A lower percentage of isolates had the dnt gene (72.7%) and the lowest percentage of strains (51.7%), had the bfrZ gene. PMID:24724472

  8. Identification of novel anti-inflammatory probiotic strains isolated from pulque.

    PubMed

    Torres-Maravilla, Edgar; Lenoir, Marion; Mayorga-Reyes, Lino; Allain, Thibault; Sokol, Harry; Langella, Philippe; Sánchez-Pardo, María E; Bermúdez-Humarán, Luis G

    2016-01-01

    Probiotics are live microorganisms which when administered in adequate amounts, confer health benefits on the host. Their use is more and more widespread for both prevention and treatment of diseases, including traveler’s diarrhea and inflammatory bowel diseases (IBDs). In this work, we isolated and characterized novel candidate probiotic strains from pulque (xaxtle), a traditional Mexican alcoholic fermented beverage. A total of 14 strains were obtained from xaxtle samples isolated from three different Mexican regions. Species identification was performed by biochemical methods and 16S rRNA gene targeted PCR. The isolates belonged to the Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, and Lactobacillus composti phylogenetic groups, with L. brevis being the most dominant group. Bacteria were tested for lysozyme, low pH, and bile acid resistance. Moreover, the strains were tested for adherence to human intestinal epithelial cells and screened for their immunomodulatory properties using a cellular model. Selected bacterial strains with anti-inflammatory properties were then tested in vivo in a dinitro-benzene sulfonic acid (DNBS)-induced chronic colitis mouse model, and weight loss, gut permeability, and cytokine profiles were measured as readouts of inflammation. One of the selected strains, Lactobacillus sanfranciscensis LBH1068, improved mice health as observed by a reduction of weight loss, significant decreases in gut permeability, and cytokine modulation. Altogether, our results highlighted the potential of lactobacilli isolated from pulque and in particular the strain L. sanfranciscensis LBH1068 as a novel probiotic to treat IBD.

  9. [Studies on Vibrio vulnificus infection: molecular epidemiology of environment-derived strains and clinical isolates].

    PubMed

    Oonaka, Kenji; Furuhata, Katsunori; Hara, Motonobu; Fukuyama, Masafumi

    2007-01-01

    To clarify the route and source of Vibrio vulnificus infection, we conducted molecular epidemiological investigation by DNA analysis of 355 environmental isolates (seawater-derived strain: 86, sea mud-derived strain:36, and oyster-derived strain: 233) and 65 human clinical isolates, for a total of 420 isolates, using pulse field gel electrophoresis (PFGE), with the following results. 1. When DNA was cleaved with 2 enzymes, Not I and Sfi I, and subjected to PFGE, Not I DNA interpretation was 76.9%, and Sfi I cleavage was 97.9%, showing that Sfi I was superior in cleaving DNA of this bacteria. 2. Sfi I-interpreted strains were subjected to PFGE and migration patterns were analyzed by UPGMA, but close classification was not possible because similarity was low, this infectious disease clearly originated from multiple rather than a single-clone. In this cluster, we concluded that this infectious disease was acquired through contact between the environment and human beings and viceversa. We identified an assortment of clinical isolates and environment-derived strains among more than 89% of strain groups tested, none of which could be expected to have the same origin. We conclued DNA analysis on these two types of restriction enzymes using PFGE, but were unable to classify test results in detail due to the proliferation of migration patterns and low degree of similarity.

  10. Probiotic potential of selected lactic acid bacteria strains isolated from Brazilian kefir grains.

    PubMed

    Leite, A M O; Miguel, M A L; Peixoto, R S; Ruas-Madiedo, P; Paschoalin, V M F; Mayo, B; Delgado, S

    2015-06-01

    A total of 34 lactic acid bacteria isolates from 4 different Brazilian kefir grains were identified and characterized among a group of 150 isolates, using the ability to tolerate acidic pH and resistance to bile salts as restrictive criteria for probiotic potential. All isolates were identified by amplified ribosomal DNA restriction analysis and 16S rDNA sequencing of representative amplicons. Eighteen isolates belonged to the species Leuconostoc mesenteroides, 11 to Lactococcus lactis (of which 8 belonged to subspecies cremoris and 3 to subspecies lactis), and 5 to Lactobacillus paracasei. To exclude replicates, a molecular typing analysis was performed by combining repetitive extragenic palindromic-PCR and random amplification of polymorphic DNA techniques. Considering a threshold of 90% similarity, 32 different strains were considered. All strains showed some antagonistic activity against 4 model food pathogens. In addition, 3 Lc. lactis strains and 1 Lb. paracasei produced bacteriocin-like inhibitory substances against at least 2 indicator organisms. Moreover, 1 Lc. lactis and 2 Lb. paracasei presented good total antioxidative activity. None of these strains showed undesirable enzymatic or hemolytic activities, while proving susceptible or intrinsically resistant to a series of clinically relevant antibiotics. The Lb. paracasei strain MRS59 showed a level of adhesion to human Caco-2 epithelial cells comparable with that observed for Lactobacillus rhamnosus GG. Taken together, these properties allow the MRS59 strain to be considered a promising probiotic candidate.

  11. Phenotypic and genotypic characterization of Bordetella bronchiseptica strains isolated from pigs in Poland.

    PubMed

    Stepniewska, K; Urbaniak, K; Markowska-Daniel, I

    2014-01-01

    A total of 209 Bordetella bronchiseptica (Bbr) strains isolated from pigs were examined. Phenotypic study included: biochemical characterization (motility, catalase, oxidase, urease activity, nitrate reduction and growth on MacConkey agar) and antimicrobial susceptibility (disc diffusion method). Genotypic studies based on detection of three genes encoded virulence factors, such as: flagella (fla), dermonecrotoxin (dnt), and exogenous ferric siderophore receptor (bfrZ), using PCR. Most of the Bbr strains tested had a homogeneous biochemical profile. 97.6% of them provided suitable results in biochemical tests. All Bbr isolates tested showed high resistance to penicillin (100%), linco-spectin (100%) and ceftiofur (97.9%). Over 57% and 43% of Bbr strains were resistant to ampicillin and amoxicillin, respectively. All Bbr isolates showed high sensitivity to most chemotherapeutics used such as enrofloxacin (97.9%), tetracycline (97.9%), oxytetracycline (97.9%), amoxicillin with clavulonic acid (95.8%), florfenicol (90.4%), and gentamicine (77.6%). Over of 94% of Bbr strains were moderately susceptible to norfloxacine. Molecular analysis confirmed that almost all evaluated Bbr strains (94.7%) possessed the fla gene. A lower percentage of isolates had the dnt gene (72.7%) and the lowest percentage of strains (51.7%), had the bfrZ gene.

  12. Biodegradation of Ochratoxin A by Bacterial Strains Isolated from Vineyard Soils

    PubMed Central

    De Bellis, Palmira; Tristezza, Mariana; Haidukowski, Miriam; Fanelli, Francesca; Sisto, Angelo; Mulè, Giuseppina; Grieco, Francesco

    2015-01-01

    Ochratoxin A (OTA) is a mycotoxin with a main nephrotoxic activity contaminating several foodstuffs. In the present report, five soil samples collected from OTA-contaminated vineyards were screened to isolate microorganisms able to biodegrade OTA. When cultivated in OTA-supplemented medium, OTA was converted in OTα by 225 bacterial isolates. To reveal clonal relationships between isolates, molecular typing by using an automated rep-PCR system was carried out, thus showing the presence of 27 different strains (rep-PCR profiles). The 16S-rRNA gene sequence analysis of an isolate representative of each rep-PCR profiles indicated that they belonged to five bacterial genera, namely Pseudomonas, Leclercia, Pantoea, Enterobacter, and Acinetobacter. However, further evaluation of OTA-degrading activity by the 27 strains revealed that only Acinetobacter calcoaceticus strain 396.1 and Acinetobacter sp. strain neg1, consistently conserved the above property; their further characterization showed that they were able to convert 82% and 91% OTA into OTα in six days at 24 °C, respectively. The presence of OTα, as the unique OTA-degradation product was confirmed by LC-HRMS. This is the first report on OTA biodegradation by bacterial strains isolated from agricultural soils and carried out under aerobic conditions and moderate temperatures. These microorganisms might be used to detoxify OTA-contaminated feed and could be a new source of gene(s) for the development of a novel enzymatic detoxification system. PMID:26633497

  13. Characterization of Yersinia enterocolitica Biotype 1A Strains Isolated from Swine Slaughterhouses and Markets

    PubMed Central

    Paixão, Renata; Moreno, Luisa Zanolli; Sena de Gobbi, Débora Dirani; Raimundo, Daniele Cristine; Hofer, Ernesto; Matté, Maria Helena; Ferreira, Thais Sebastiana Porfida; Gomes, Vasco Tulio de Moura; Costa, Barbara Leticia Pereira; Moreno, Andrea Micke

    2013-01-01

    Yersinia enterocolitica is an important foodborne pathogen that causes illness in humans and animals. Y. enterocolitica is also the most heterogeneous species of the genus and is divided into distinct serotypes and over six biotypes. Y. enterocolitica biotype 1A strains are classically considered as nonpathogenic; however, some biotype 1A isolates have been considered as causative of gastrointestinal disease, yielding symptoms indistinguishable from those produced by pathogenic biotypes. Even after decades of isolation of clinical strains, the pathogenic mechanisms of these isolates are still not fully understood. In the present study, 122 Yersinia enterocolitica biotype 1A strains isolated from swine slaughterhouses and meat markets in Sao Paulo, Brazil, were characterized according to the presence of the virulence genes ail, virF, and ystA. A total of 94 strains were positive to at least one virulence gene (77.05%), and 67 were positive to all of them (54.92%). Twenty-two strains were submitted to PFGE genotyping resulting in 22 distinct pulsotypes, varying from 50% to 84% of genetic similarity. Any clustering tendency among pulsotypes related to origin, isolation site, or even virulence profile was not observed. The present study reports an important contamination of the environment in swine slaughterhouses, meat markets, and pork, by potentially virulent Y. enterocolitica biotype 1A. PMID:23476146

  14. Biodegradation of Ochratoxin A by Bacterial Strains Isolated from Vineyard Soils.

    PubMed

    De Bellis, Palmira; Tristezza, Mariana; Haidukowski, Miriam; Fanelli, Francesca; Sisto, Angelo; Mulè, Giuseppina; Grieco, Francesco

    2015-12-01

    Ochratoxin A (OTA) is a mycotoxin with a main nephrotoxic activity contaminating several foodstuffs. In the present report, five soil samples collected from OTA-contaminated vineyards were screened to isolate microorganisms able to biodegrade OTA. When cultivated in OTA-supplemented medium, OTA was converted in OTα by 225 bacterial isolates. To reveal clonal relationships between isolates, molecular typing by using an automated rep-PCR system was carried out, thus showing the presence of 27 different strains (rep-PCR profiles). The 16S-rRNA gene sequence analysis of an isolate representative of each rep-PCR profiles indicated that they belonged to five bacterial genera, namely Pseudomonas, Leclercia, Pantoea, Enterobacter, and Acinetobacter. However, further evaluation of OTA-degrading activity by the 27 strains revealed that only Acinetobacter calcoaceticus strain 396.1 and Acinetobacter sp. strain neg1, consistently conserved the above property; their further characterization showed that they were able to convert 82% and 91% OTA into OTα in six days at 24 °C, respectively. The presence of OTα, as the unique OTA-degradation product was confirmed by LC-HRMS. This is the first report on OTA biodegradation by bacterial strains isolated from agricultural soils and carried out under aerobic conditions and moderate temperatures. These microorganisms might be used to detoxify OTA-contaminated feed and could be a new source of gene(s) for the development of a novel enzymatic detoxification system. PMID:26633497

  15. Antibiotic Resistance Determinants in a Pseudomonas putida Strain Isolated from a Hospital

    PubMed Central

    Duque, Estrella; Fernández, Matilde; Molina-Santiago, Carlos; Roca, Amalia; Porcel, Mario; de la Torre, Jesús; Segura, Ana; Plesiat, Patrick; Jeannot, Katy; Ramos, Juan-Luis

    2014-01-01

    Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267) kills insects and is resistant to the majority of the antibiotics used in laboratories and hospitals, including aminoglycosides, ß-lactams, cationic peptides, chromoprotein enediyne antibiotics, dihydrofolate reductase inhibitors, fluoroquinolones and quinolones, glycopeptide antibiotics, macrolides, polyketides and sulfonamides. Similar to other P. putida clinical isolates the strain was sensitive to amikacin. To shed light on the broad pattern of antibiotic resistance, which is rarely found in clinical isolates of this species, the genome of this strain was sequenced and analysed. The study revealed that the determinants of multiple resistance are both chromosomally-borne as well as located on the pPC9 plasmid. Further analysis indicated that pPC9 has recruited antibiotic and biocide resistance genes from environmental microorganisms as well as from opportunistic and true human pathogens. The pPC9 plasmid is not self-transmissible, but can be mobilized by other bacterial plasmids making it capable of spreading antibiotic resistant determinants to new hosts. PMID:24465371

  16. Isolation and screening of strains producing high amounts of rutin degrading enzymes from Fagopyrum tataricum seeds.

    PubMed

    Zheng, Ya-Di; Luo, Qing-Lin; Zhou, Mei-Liang; Wang, De-Zhou; Zhang, Ye-Dong; Shao, Ji-Rong; Zhu, Xue-Mei; Tang, Yu

    2013-02-01

    The rutin degrading enzyme (RDE) was isolated and purified from tartary buckwheat seeds. The RDE was purified about 11.34-fold and its final yield was 3.5%, which was very low, due to our purification strategy of giving priority to purity over yield. The RDE molecular weight was estimated to be about 60 kDa. When rutin was used as substrate, an optimal enzyme activity was seen at around pH 5.0 and 40 °C. Strains isolation strategy characterized by the use of rutin as sole carbon source in enrichment cultures was used to isolate RDE-producing strains. Then the active strains were identified by morphology characterization and 18s rDNA-ITS (Internal Transcribed Spacer) gene sequencing. Three isolates coded as B3, W2, Y2 were successfully isolated from fusty Fagopyrum tataricum flour cultures. Strain B3 possessed the highest unit activity among these three strains, and its total activity reached up to 171.0 Unit. The active isolate (B3) could be assigned to Penicillium farinosum. When the Penicillium farinosum strains were added to tartary buckwheat flour cultures at pH 5.0, 30 °C after 5 days fermentation, the quercetin production raised up to 1.78 mg/l, almost 5.1 times higher than the fermentation without the above active strains. Hence, a new approach was available to utilize microorganism-aided fermentation for effective quercetin extraction from Fagopyrum tataricum seeds.

  17. Characterization and probiotic potential of Lactobacillus plantarum strains isolated from cheeses.

    PubMed

    Zago, Miriam; Fornasari, Maria Emanuela; Carminati, Domenico; Burns, Patricia; Suàrez, Viviana; Vinderola, Gabriel; Reinheimer, Jorge; Giraffa, Giorgio

    2011-08-01

    Ninety-eight Lactobacillus plantarum strains isolated from Italian and Argentinean cheeses were evaluated for probiotic potential. After a preliminary subtractive screening based on the presence of msa and bsh genes, 27 strains were characterized. In general, the selected strains showed high resistance to lysozyme, good adaptation to simulated gastric juice, and a moderate to low bile tolerance. The capacity to agglutinate yeast cells in a mannose-specific manner, as well as the cell surface hydrophobicity was found to be variable among strains. Very high β-galactosidase activity was shown by a considerable number of the tested strains, whereas variable prebiotic utilization ability was observed. Only tetracycline resistance was observed in two highly resistant strains which harbored the tetM gene, whereas none of the strains showed β-glucuronidase activity or was capable of inhibiting pathogens. Three strains (Lp790, Lp813, and Lp998) were tested by in vivo trials. A considerable heterogeneity was found among a number of L. plantarum strains screened in this study, leading to the design of multiple cultures to cooperatively link strains showing the widest range of useful traits. Among the selected strains, Lp790, Lp813, and Lp998 showed the best probiotic potential and would be promising candidates for inclusion as starter cultures for the manufacture of probiotic fermented foods. PMID:21569949

  18. Antimicrobial activities of rhizobacterial strains of Pseudomonas and Bacillus strains isolated from rhizosphere soil of carnation (Dianthus caryophyllus cv. Sunrise).

    PubMed

    Sharma, Sapna; Kaur, Mohinder

    2010-06-01

    Under the present study, an attempt was made to characterize rhizobacteria i.e. Pseudomonas and Bacillus species isolated from rhizosphere of carnation to evaluate their growth promoting effect on carnation so as to select and develop more efficient indigenous plant growth promoting and disease suppressing bioagents of specific soil type and specific plant type. Maximum strains of Pseudomonas and Bacillus sp. showed significant antimicrobial activities against most of the microorganisms tested. On the basis of in vitro antagonistic activities, the best strains were selected and used in field trial to study the influence of these strains on the growth of carnation. Results have shown marked effect on growth parameters and disease incidence has also been reduced significantly.

  19. Genotypes of Leptospira spp. strains isolated from dogs in Buenos Aires, Argentina.

    PubMed

    Grune Loffler, Sylvia; Passaro, Diego; Samartino, Luis; Soncini, Analía; Romero, Graciela; Brihuega, Bibiana

    2014-01-01

    Leptospirosis is an infectious disease of wide global distribution, which is endemic in Argentina. The objective of this study was to obtain the genetic profiles of Leptospira spp. strains isolated from clinical cases of dogs in the province of Buenos Aires by the multiple-locus variable-number tandem repeat analysis (MLVA). Eight isolated canine strains were genotyped by MLVA, obtaining the identical profile of Leptospira interrogans serovar Canicola Hond Utrecht IV in the strains named Dogy and Mayo. The strains named Bel, Sarmiento, La Plata 4581 and La Plata 5478 were identical to the profile of the genotype of L. interrogans serovar Portlandvere MY 1039.The strain named Avellaneda was identical to the genotype profile of L. interrogans serovar Icterohaemorrhagiae RGA and the strain named SB had the same profile as the L. interrogans serovar Pomona Baires genotype and was similar to the profile of serovar Pomona Pomona genotype. It would be useful to include a larger number of isolates from different dog populations in various provinces of Argentina and to characterize the genetic profiles of the strains circulating in the country. The information obtained will be useful for the control of leptospirosis in the dog population.

  20. Permissiveness of freshly isolated environmental strains of amoebae for growth of Legionella pneumophila.

    PubMed

    Dupuy, Mathieu; Binet, Marie; Bouteleux, Celine; Herbelin, Pascaline; Soreau, Sylvie; Héchard, Yann

    2016-03-01

    Legionella pneumophila is a pathogenic bacterium commonly found in water and responsible for severe pneumonia. Free-living amoebae are protozoa also found in water, which feed on bacteria by phagocytosis. Under favorable conditions, some L. pneumophila are able to resist phagocytic digestion and even multiply within amoebae. However, it is not clear whether L. pneumophila could infect at a same rate a large range of amoebae or if there is some selectivity towards specific amoebal genera or strains. Also, most studies have been performed using collection strains and not with freshly isolated strains. In our study, we assess the permissiveness of freshly isolated environmental strains of amoebae, belonging to three common genera (i.e. Acanthamoeba, Naegleria and Vermamoeba), for growth of L. pneumophila at three different temperatures. Our results indicated that all the tested strains of amoebae were permissive to L. pneumophila Lens and that there was no significant difference between the strains. Intracellular proliferation was more efficient at a temperature of 40°C. In conclusion, our work suggests that, under favorable conditions, virulent strains of L. pneumophila could equally infect a large number of isolates of common freshwater amoeba genera.

  1. Permissiveness of freshly isolated environmental strains of amoebae for growth of Legionella pneumophila.

    PubMed

    Dupuy, Mathieu; Binet, Marie; Bouteleux, Celine; Herbelin, Pascaline; Soreau, Sylvie; Héchard, Yann

    2016-03-01

    Legionella pneumophila is a pathogenic bacterium commonly found in water and responsible for severe pneumonia. Free-living amoebae are protozoa also found in water, which feed on bacteria by phagocytosis. Under favorable conditions, some L. pneumophila are able to resist phagocytic digestion and even multiply within amoebae. However, it is not clear whether L. pneumophila could infect at a same rate a large range of amoebae or if there is some selectivity towards specific amoebal genera or strains. Also, most studies have been performed using collection strains and not with freshly isolated strains. In our study, we assess the permissiveness of freshly isolated environmental strains of amoebae, belonging to three common genera (i.e. Acanthamoeba, Naegleria and Vermamoeba), for growth of L. pneumophila at three different temperatures. Our results indicated that all the tested strains of amoebae were permissive to L. pneumophila Lens and that there was no significant difference between the strains. Intracellular proliferation was more efficient at a temperature of 40°C. In conclusion, our work suggests that, under favorable conditions, virulent strains of L. pneumophila could equally infect a large number of isolates of common freshwater amoeba genera. PMID:26832643

  2. Study of Corynebacterium diphtheriae strains isolated in Romania, northwestern Russia and the Republic of Moldova.

    PubMed

    Damian, Maria; Grimont, Francine; Narvskaya, Olga; Straut, Monica; Surdeanu, Maria; Cojocaru, Radu; Mokrousov, Igor; Diaconescu, Angela; Andronescu, Constantin; Melnic, Anatol; Mutoi, Ludmila; Grimont, Patrick A D

    2002-03-01

    A selection of 167 Corynebacterium diphtheriae strains isolated in Romania, the Russian Federation and the Republic of Moldova were analysed by biotyping, phage typing, the toxin production test and by molecular techniques such as ribotyping, pulsed field gel electrophoresis and random amplified polymorphic DNA, in order to establish the epidemiological relatedness, genetic divergence and strain circulation within and between the bordering countries. Using a set of five digoxigenin-labeled oligonucleotides and BstEII digestion, 34 ribotypes were identified. The strains isolated in the epidemic areas (Russia and Moldova) were very closely related but different from those isolated in Romania. C1 and C5 were the main ribotypes identified in these areas. Neither ribotype was found in Romania, where the main circulating types were C3 and C7. Field inversion gel electrophoresis was more discriminative than ribotyping and revealed 54 macrorestriction profiles after SfiI restriction. Both methods showed a significant homogeneity of the strains from epidemic areas and a large diversity among the Romanian strains. Random amplification was useful as an identification method for the epidemic strains, but not for the Romanian ones which displayed a large number of amplification profiles. The phenotypic methods associated with molecular typing techniques enabled distinguishing between strains, detecting the epidemic clone, and sustaining the absence of transmission across borders.

  3. Genotypes of Leptospira spp. strains isolated from dogs in Buenos Aires, Argentina.

    PubMed

    Grune Loffler, Sylvia; Passaro, Diego; Samartino, Luis; Soncini, Analía; Romero, Graciela; Brihuega, Bibiana

    2014-01-01

    Leptospirosis is an infectious disease of wide global distribution, which is endemic in Argentina. The objective of this study was to obtain the genetic profiles of Leptospira spp. strains isolated from clinical cases of dogs in the province of Buenos Aires by the multiple-locus variable-number tandem repeat analysis (MLVA). Eight isolated canine strains were genotyped by MLVA, obtaining the identical profile of Leptospira interrogans serovar Canicola Hond Utrecht IV in the strains named Dogy and Mayo. The strains named Bel, Sarmiento, La Plata 4581 and La Plata 5478 were identical to the profile of the genotype of L. interrogans serovar Portlandvere MY 1039.The strain named Avellaneda was identical to the genotype profile of L. interrogans serovar Icterohaemorrhagiae RGA and the strain named SB had the same profile as the L. interrogans serovar Pomona Baires genotype and was similar to the profile of serovar Pomona Pomona genotype. It would be useful to include a larger number of isolates from different dog populations in various provinces of Argentina and to characterize the genetic profiles of the strains circulating in the country. The information obtained will be useful for the control of leptospirosis in the dog population. PMID:25444128

  4. Antibiotic susceptibility, antibacterial activity and characterisation of Enterococcus faecium strains isolated from breast milk

    PubMed Central

    Kıvanç, Sertaç Argun; Kıvanç, Merih; Yiğit, Tülay

    2016-01-01

    Enterococci, which have useful biotechnological applications, produce bacteriocins, including those that exert anti-Listerial activity. The present study aimed to determine the antibiotic susceptibility patterns and antimicrobial activity of Enterococcus faecium strains isolated from human breast milk. The strains were identified using carbohydrate fermentation tests and ribotyping. Subsequently, the antibacterial activity of the isolates was investigated, and the quantities of lactic acid and hydrogen peroxide produced, and the proteolytic activity of E. faecium, were determined. In addition, biofilm formation by E. faecium strains was assessed. E. faecium strains exhibited antimicrobial activity against food-borne and clinical bacterial isolates. Furthermore, following 24 h incubation, the tested strains exhibited resistance to a pH range of 2.0–9.5 and tolerance of bile acid, lysozyme activity and phenol. Supernatants of the E. faecium TM13, TM15, TM17 and TM18 strains were shown to be effective against Listeria monocytogenes, and were also resistant to heat. Further studies are required in order to determine whether certain strains of E. faecium may be used for the development of novel antibacterial agents. PMID:27602088

  5. Antibiotic susceptibility, antibacterial activity and characterisation of Enterococcus faecium strains isolated from breast milk

    PubMed Central

    Kıvanç, Sertaç Argun; Kıvanç, Merih; Yiğit, Tülay

    2016-01-01

    Enterococci, which have useful biotechnological applications, produce bacteriocins, including those that exert anti-Listerial activity. The present study aimed to determine the antibiotic susceptibility patterns and antimicrobial activity of Enterococcus faecium strains isolated from human breast milk. The strains were identified using carbohydrate fermentation tests and ribotyping. Subsequently, the antibacterial activity of the isolates was investigated, and the quantities of lactic acid and hydrogen peroxide produced, and the proteolytic activity of E. faecium, were determined. In addition, biofilm formation by E. faecium strains was assessed. E. faecium strains exhibited antimicrobial activity against food-borne and clinical bacterial isolates. Furthermore, following 24 h incubation, the tested strains exhibited resistance to a pH range of 2.0–9.5 and tolerance of bile acid, lysozyme activity and phenol. Supernatants of the E. faecium TM13, TM15, TM17 and TM18 strains were shown to be effective against Listeria monocytogenes, and were also resistant to heat. Further studies are required in order to determine whether certain strains of E. faecium may be used for the development of novel antibacterial agents.

  6. Molecular characterization of two Bordetella bronchiseptica strains isolated from children with coughs.

    PubMed Central

    Stefanelli, P; Mastrantonio, P; Hausman, S Z; Giuliano, M; Burns, D L

    1997-01-01

    During a surveillance program associated with the Italian clinical trial for the evaluation of new acellular pertussis vaccines, two bacterial isolates were obtained in cultures of samples from immunocompetent infants who had episodes of cough. Both clinical isolates were identified as Bordetella bronchiseptica by biochemical criteria, although both strains agglutinated with antisera specific for Bordetella parapertussis, suggesting that the strains exhibited some characteristics of both B. bronchiseptica and B. parapertussis. Both children from whom these strains were isolated exhibited an increase in serum antibody titer to pertussis toxin (PT), a protein that is produced by Bordetella pertussis but that is not thought to be produced by B. bronchiseptica. We therefore examined whether the clinical isolates were capable of producing PT. Neither strain produced PT under laboratory conditions, although both strains appeared to contain a portion of the ptx region that encodes the structural subunits of PT. In order to determine whether the ptx genes may encode functional proteins, we inserted an active promoter directly upstream of the ptx region of one of these strains. Biologically active PT was produced, suggesting that this strain contains the genetic information necessary to encode an active PT molecule. Sequence analysis of the ptx promoter region of both strains indicated that, while they shared homology with the B. bronchiseptica ATCC 4617 sequence, they contained certain sequence motifs that are characteristic of B. parapertussis and certain motifs that are characteristic of B. pertussis. Taken together, these findings suggest that variant strains of B. bronchiseptica exist and might be capable of causing significant illness in humans. PMID:9163480

  7. Comparative virulence studies and transcriptome analysis of Staphylococcus aureus strains isolated from animals

    PubMed Central

    Iqbal, Zahid; Seleem, Mohamed N.; Hussain, Hafiz Iftikhar; Huang, Lingli; Hao, Haihong; Yuan, Zonghui

    2016-01-01

    Several studies have been conducted to check the prevalence of methicillin-resistant strains of Staphylococcus aureus (MRSA) in animals and animal-derived food products but limited data are available regarding their virulence and associated gene expression profile. In the present study, antibiotic resistance and virulence of MRSA and methicillin-sensitive S. aureus animal isolates were determined in vitro by agar dilution, biofilm formation, adhesion, invasion and intracellular survivability assays. In addition, the pathogenicity of these isolates was examined in a murine model of S. aureus sepsis. MRSA1679a, a strain isolated from chicken, was observed to be highly virulent, in cell culture and in mouse model, and exhibited extensive resistant profile. Comparative gene expression profile of MRSA1679a and the reference human MRSA strain (ATCC 29213) was performed using Illumina-based transcriptome and RT-qPCR analyses. Several virulence elements including 22 toxin genes were detected in MRSA animal-isolate. In addition, we observed enhanced expression of crucial virulence regulators, such as sarA and KdpDE in MRSA animal-isolate compared to the human isolate. Collectively, gene expression profile including several virulence and drug-resistance factors confirmed the unique and highly virulent determinants of the MRSA strain of poultry origin which warrants further attention due to significant threat to public health. PMID:27739497

  8. Assessment of potentially probiotic properties of Lactobacillus strains isolated from chickens.

    PubMed

    Kizerwetter-Świda, M; Binek, M

    2016-01-01

    This study was performed in order to isolate lactobacilli from chicken droppings and to select strains with the most promising probiotic properties. Lactobacillus strains were isolated from a flock of healthy laying hens. The first selection criterion was the ability to inhibit the growth of Salmonella Enteritidis. Then the tolerance to low pH and bile salt, the ability to coaggregate with pathogenic bacteria and hydrogen peroxide production were evaluated. Four isolates showing the best antagonistic activity against Salmonella Enetritidis were selected for further research. All isolates tested tolerated low pH and bile salt, likewise all produced hydrogen peroxide. They efficiently coaggregated with C. perfringens and relatively less with E. coli. Isolate 03'04 displayed above-average results in all criteria, thus it is considered as a potential probiotic for chickens, and will be further evaluated for health promoting effect in animals. The results presented in this study confirm the strain specific probiotic properties and prove the probiotic potential of isolate 03'04. Strong antagonistic properties against C. perfringens exhibited by certain Lactobacillus strains indicate the possibility to use them as a component of probiotic supplement in necrotic enteritis of poultry. PMID:27096783

  9. Draft Genome Sequences of 40 Salmonella enterica Serovar Typhimurium Strains Isolated from Humans and Food in Brazil

    PubMed Central

    Almeida, Fernanda; Medeiros, Marta Inês Cazentini; Rodrigues, Dália Prazeres; Payne, Justin; Timme, Ruth E.

    2016-01-01

    Salmonellosis is an important health problem worldwide and Salmonella enterica serovar Typhimurium is one of the most common isolated serovars. Here, we reported the draft genomes of 40 S. Typhimurium strains isolated from humans and food in Brazil. These draft genomes will improve phylogenetic analysis and will help enhance our understanding of strains of this serovar isolated in Brazil. PMID:27660768

  10. Draft Genome Sequences of 40 Salmonella enterica Serovar Typhimurium Strains Isolated from Humans and Food in Brazil.

    PubMed

    Almeida, Fernanda; Medeiros, Marta Inês Cazentini; Rodrigues, Dália Prazeres; Payne, Justin; Timme, Ruth E; Allard, Marc W; Falcão, Juliana Pfrimer

    2016-01-01

    Salmonellosis is an important health problem worldwide and Salmonella enterica serovar Typhimurium is one of the most common isolated serovars. Here, we reported the draft genomes of 40 S Typhimurium strains isolated from humans and food in Brazil. These draft genomes will improve phylogenetic analysis and will help enhance our understanding of strains of this serovar isolated in Brazil. PMID:27660768

  11. Characterization of Vibrio tapetis strains isolated from diseased cultured Wedge sole (Dicologoglossa cuneata Moreau).

    PubMed

    López, J R; Balboa, S; Núñez, S; de la Roca, E; de la Herran, R; Navas, J I; Toranzo, A E; Romalde, J L

    2011-04-01

    The first isolation of Vibrio tapetis from Wedge sole (Dicologoglossa cuneata) is reported. The bacterium was recovered from ulcers of ailing cultured fish, from two different outbreaks occurred in spring 2005. The four isolates found (a200, a201, a204 and a255) were biochemically, genetically and serologically characterized and diagnosis was confirmed by PCR V. tapetis specific primers and multilocus sequencing analysis (MLSA). The isolates constituted a homogeneous phenotypic and genotypic group, being distinct to the already serological and genetic groups defined within the species. A virulence evaluation of the isolate a255 was also carried out; however this strain was unable to induce disease in fry and juvenile Wedge sole.

  12. Necrotizing fasciitis caused by Aeromonas caviae.

    PubMed

    Kumar, Simit; Mukhopadhyay, Prabir; Chatterjee, Mitali; Bandyopadhyay, Manas K; Bandyopadhyay, Maitreyi; Ghosh, Tapashi; Samaddar, Debopriyo

    2012-10-01

    Aeromonads are rarely associated with human intestinal and extra-intestinal diseases and syndromes, ranging from relatively mild illnesses such as acute gastroenteritis to life-threatening conditions, including septicemia, necrotizing fasciitis, and myonecrosis. Among the aeromonas species known to cause human infection, Aeromonas caviae has been associated with septicemia and only one reported case of human soft tissue infection. Most of the infections due to aeromonas occur in immunocompromised patients. Herein we describe a successfully treated case of post-traumatic skin and soft-tissue infections due to A. caviae in an otherwise immunocompetent individual.

  13. Immunization with recombinant aerolysin and hemolysin protected channel catfish against virulent Aeromonas hydrophila

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila is emerging as one of the major concerns in catfish aquaculture in the Southeastern United States due to recent outbreaks of motile aeromonad septicemia (MAS) caused by virulent clonal isolates. There is no effective vaccine currently available for the prevention of MAS. In this...

  14. Comparative genomics of two newly isolated Dehalococcoides strains and an enrichment using a genus microarray

    PubMed Central

    Lee, Patrick K H; Cheng, Dan; Hu, Ping; West, Kimberlee A; Dick, Gregory J; Brodie, Eoin L; Andersen, Gary L; Zinder, Stephen H; He, Jianzhong; Alvarez-Cohen, Lisa

    2011-01-01

    Comparative genomics of Dehalococcoides strains and an enrichment were performed using a microarray targeting genes from all available sequenced genomes of the Dehalococcoides genus. The microarray was designed with 4305 probe sets to target 98.6% of the open-reading frames from strains 195, CBDB1, BAV1 and VS. The microarrays were validated and applied to query the genomes of two recently isolated Dehalococcoides strains, ANAS1 and ANAS2, and their enrichment source (ANAS) to understand the genome–physiology relationships. Strains ANAS1 and ANAS2 can both couple the reduction of trichloroethene, cis-dichloroethene (DCE) and 1,1-DCE, but not tetrachloroethene and trans-DCE with growth, whereas only strain ANAS2 couples vinyl chloride reduction to growth. Comparative genomic analysis showed that the genomes of both strains are similar to each other and to strain 195, except for genes that are within the previously defined integrated elements or high-plasticity regions. Combined results of the two isolates closely matched the results obtained using genomic DNA of the ANAS enrichment. The genome similarities, together with the distinct chlorinated ethene usage of strains ANAS1, ANAS2 and 195 demonstrate that closely phylogenetically related strains can be physiologically different. This incongruence between physiology and core genome phylogeny seems to be related to the presence of distinct reductive dehalogenase-encoding genes with assigned chlorinated ethene functions (pceA, tceA in strain 195; tceA in strain ANAS1; vcrA in strain ANAS2). Overall, the microarrays are a valuable high-throughput tool for comparative genomics of unsequenced Dehalococcoides-containing samples to provide insights into their gene content and dechlorination functions. PMID:21228894

  15. Isolation and characterization of thermotolerant Gluconobacter strains catalyzing oxidative fermentation at higher temperatures.

    PubMed

    Moonmangmee, D; Adachi, O; Ano, Y; Shinagawa, E; Toyama, H; Theeragool, G; Lotong, N; Matsushita, K

    2000-11-01

    Thermotolerant acetic acid bacteria belonging to the genus Gluconobacter were isolated from various kinds of fruits and flowers from Thailand and Japan. The screening strategy was built up to exclude Acetobacter strains by adding gluconic acid to a culture medium in the presence of 1% D-sorbitol or 1% D-mannitol. Eight strains of thermotolerant Gluconobacter were isolated and screened for D-fructose and L-sorbose production. They grew at wide range of temperatures from 10 degrees C to 37 degrees C and had average optimum growth temperature between 30-33 degrees C. All strains were able to produce L-sorbose and D-fructose at higher temperatures such as 37 degrees C. The 16S rRNA sequences analysis showed that the isolated strains were almost identical to G. frateurii with scores of 99.36-99.79%. Among these eight strains, especially strains CHM16 and CHM54 had high oxidase activity for D-mannitol and D-sorbitol, converting it to D-fructose and L-sorbose at 37 degrees C, respectively. Sugar alcohols oxidation proceeded without a lag time, but Gluconobacter frateurii IFO 3264T was unable to do such fermentation at 37 degrees C. Fermentation efficiency and fermentation rate of the strains CHM16 and CHM54 were quite high and they rapidly oxidized D-mannitol and D-sorbitol to D-fructose and L-sorbose at almost 100% within 24 h at 30 degrees C. Even oxidative fermentation of D-fructose done at 37 degrees C, the strain CHM16 still accumulated D-fructose at 80% within 24 h. The efficiency of L-sorbose fermentation by the strain CHM54 at 37 degrees C was superior to that observed at 30 degrees C. Thus, the eight strains were finally classified as thermotolerant members of G. frateurii.

  16. [Frequency of isolation and antibiotic sensitivity of strains of coli bacilli from urinary tract infections isolated in private laboratories].

    PubMed

    Bourlioux, P; Bourlioux, N; Bournaud, M

    1983-06-01

    Frequency of isolation and antibiotic susceptibility of E. coli strains isolated from urinary tract infections in private laboratory. The urinary tract infections are not the most frequent infections in man. However cytobacteriological analysis are often required for the diagnosis. The critical evaluation of 3000 analysis brings the followed conclusions: 1) 16% of the analysis correspond to a urinary tract infection; 2) the most frequently isolated germs are E. coli (65%) and Proteus mirabilis (11%); 3) E. coli is always very susceptible to antibiotics especially aminosides (100%) polymyxine E (92%), cotrimoxazole (91%) and quinolones (90%); 4) hospital bacteria can be found with a low frequency. However, in our study, Staphylococcus aureus has been isolated in 6% of the cases. This seems to be in relation with the passage of patients in an obstetric clinic.

  17. MLVA typing reveals higher genetic homogeneity among S. Enteritidis strains isolated from food, humans and chickens in Brazil in comparison to the North American strains.

    PubMed

    Campioni, Fábio; Davis, Margaret; Medeiros, Marta Inês C; Falcão, Juliana P; Shah, Devendra H

    2013-03-15

    Salmonella Enteritidis (S. Enteritidis) is a major causative agent of food-borne gastroenteritis associated with the consumption of contaminated poultry products. In this study we used multilocus variable number of tandem repeats (VNTRs) analysis (MLVA) to discriminate a total of 188 S. Enteritidis strains recovered from human (n=67), food (n=61) and chickens (n=60) during a 24 year period (1986 through 2010) in Brazil. MLVA profiles of the 188 strains from Brazil were compared to the MLVA profiles of 100 human clinical (n=52) and poultry-associated (n=48) strains isolated in North America between 1986 and 2008. MLVA typing led to classification of the 288 strains from Brazil and North America into two major clusters named A and B with 35% of similarity. Cluster A consisted of a vast majority of strains isolated from North America (n=71) and only three strains isolated from Brazil which included two pre-pandemic strains (SE5 and SE4). In contrast, cluster B consisted of all of the post-pandemic strains isolated from Brazil (n=185) and fewer strains isolated from North America (n=29). In general, MLVA typing showed that the North American strains were more genetically diverse whereas Brazilian strains were more genetically clonal. The clustering of pre-pandemic strains from Brazil with the North American strains suggests the possibility that the pre-pandemic strains were more likely genetically diverse; however after 1993 a new and prevalent subtype of S. Enteritidis was introduced in this country. This is the first study describing MLVA genotyping of the S. Enteritidis strains isolated from Brazil.

  18. Isolation and characterization of novel bacterial strains exhibiting ligninolytic potential

    PubMed Central

    2011-01-01

    Background To expand on the range of products which can be obtained from lignocellulosic biomass, the lignin component should be utilized as feedstock for value-added chemicals such as substituted aromatics, instead of being incinerated for heat and energy. Enzymes could provide an effective means for lignin depolymerization into products of interest. In this study, soil bacteria were isolated by enrichment on Kraft lignin and evaluated for their ligninolytic potential as a source of novel enzymes for waste lignin valorization. Results Based on 16S rRNA gene sequencing and phenotypic characterization, the organisms were identified as Pandoraea norimbergensis LD001, Pseudomonas sp LD002 and Bacillus sp LD003. The ligninolytic capability of each of these isolates was assessed by growth on high-molecular weight and low-molecular weight lignin fractions, utilization of lignin-associated aromatic monomers and degradation of ligninolytic indicator dyes. Pandoraea norimbergensis LD001 and Pseudomonas sp. LD002 exhibited best growth on lignin fractions, but limited dye-decolourizing capacity. Bacillus sp. LD003, however, showed least efficient growth on lignin fractions but extensive dye-decolourizing capacity, with a particular preference for the recalcitrant phenothiazine dye class (Azure B, Methylene Blue and Toluidene Blue O). Conclusions Bacillus sp. LD003 was selected as a promising source of novel types of ligninolytic enzymes. Our observations suggested that lignin mineralization and depolymerization are separate events which place additional challenges on the screening of ligninolytic microorganisms for specific ligninolytic enzymes. PMID:21995752

  19. Genomic Diversity between Strains of the Same Serotype and Multilocus Sequence Type among Pneumococcal Clinical Isolates

    PubMed Central

    Silva, Nuno A.; McCluskey, Jackie; Jefferies, Johanna M. C.; Hinds, Jason; Smith, Andrew; Clarke, Stuart C.; Mitchell, Tim J.; Paterson, Gavin K.

    2006-01-01

    The important human pathogen Streptococcus pneumoniae is known to be a genetically diverse species. We have used comparative genome hybridization (CGH) microarray analysis to investigate this diversity in a collection of clinical isolates including several capsule serotype 14 pneumococci, a dominant serotype among disease isolates. We have identified three new regions of diversity among pneumococcal isolates and, importantly, clearly demonstrate genetic differences between strains of the same multilocus sequence type (ST) and capsule serotype. CGH may therefore, under certain circumstances, prove to be a valuable tool to supplement current typing methods. Finally, we show that these clonal strains with the same serotype and ST behave differently in an animal model. Strains of the same ST and serotype therefore have important genetic and phenotypic differences. PMID:16714583

  20. [Antimicrobial resistance and molecular epidemiology of Staphylococcus pseudintermedius strains isolated from dog clinical samples].

    PubMed

    Vigo, Germán B; Giacoboni, Gabriela I; Gagetti, Paula S; Pasterán, Fernando G; Corso, Alejandra C

    2015-01-01

    Twenty-eight strains isolated from dog clinical samples identified as Staphylococcus pseudintermedius by mass spectrometry (MALDI-TOF) were studied to assess antimicrobial susceptibility by the diffusion method and clonal relationship by pulsed field gel electrophoresis (PFGE). Methicillin resistance (3/28 isolates; 10,7%) was evaluated by mecA PCR. Fifteen strains (53.6%) were resistant to at least one of the antibiotics tested, and eleven of them (39.3%) showed multiple resistance (3 or more antimicrobial families). Eleven isolates (39.3%) were resistant to erythromycin due to the presence of ribosomal methylase ermB, whereas clindamycin inducible resistance was not detected. Twenty-seven (27) clonal types were differentiated by PFGE, suggesting high clonal diversity. We emphasize that the finding of multiresistant S. psedintermedius strains is an emerging problem to be considered in veterinary diagnostic laboratory treatment of canine infections and in public health settings.