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Sample records for aeromonas salmonicida yersinia

  1. Historical record of Yersinia ruckeri and Aeromonas salmonicida among sea-run Atlantic salmon (Salmo salar) in the Penobscot River

    USGS Publications Warehouse

    Cipriano, R.C.; Coll, J.

    2005-01-01

    Despite restoration efforts, only about 2,000 Atlantic salmon (Salmo salar) salmon have annually returned to New England Rivers and more than 71% of these fish migrate to the Penobscot River alone. This report provides a historical compilation on the prevalence's of both Yersinia ruckeri, cause of enteric redmouth disease, and Aeromonas salmonicida, cause of furunculosis, among mature sea-run Atlantic salmon that returned to the Penobscot River from 1976 to 2003. Aeromonas salmonicida was detected in 28.6% and Yersinia ruckeri was detected among 50% of the yearly returns. Consequently, Atlantic salmon that return to the river are potential reservoirs of infection.

  2. Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid.

    PubMed

    Meinelt, Thomas; Phan, Thy-My; Behrens, Sascha; Wienke, Andreas; Pedersen, Lars-Flemming; Liu, Dibo; Straus, David L

    2015-04-08

    Peracetic acid (PAA) is a therapeutic agent used for disinfection in aquaculture, but it must be investigated thoroughly in order to mitigate diseases without harming the fish. Successful disinfectants (like PAA) should not leave dangerous residues in the environment in order to successfully contribute to sustainable aquaculture. The aim of our study was to compare the effectiveness of 6 commercial PAA products with different molecular PAA:H2O2 ratios to reduce bacterial growth of Aeromonas salmonicida and Yersinia ruckeri and to determine effective concentrations and exposure times. All products reduced colony-forming units (CFUs) of A. salmonicida and Y. ruckeri. Products with higher molecular PAA:H2O2 ratios inhibited growth better than products with lower molecular PAA:H2O2 ratios at the same PAA concentration; this indicates that H2O2 is not the driving force in the reduction of A. salmonicida and Y. ruckeri growth by PAA in vitro. The practical application of the products with high molecular PAA:H2O2 ratios should be prioritized if these pathogens are diagnosed.

  3. Simultaneous Detection of Aeromonas salmonicida, Flavobacterium psychrophilum, and Yersinia ruckeri, Three Major Fish Pathogens, by Multiplex PCR

    PubMed Central

    del Cerro, A.; Marquez, I.; Guijarro, J. A.

    2002-01-01

    A multiplex PCR assay based on the 16S rRNA genes was developed for the simultaneous detection of three major fish pathogens, Aeromonas salmonicida, Flavobacterium psychrophilum, and Yersinia ruckeri. The assay proved to be specific and as sensitive as each single PCR assay, with detection limits in the range of 6, 0.6, and 27 CFU for A. salmonicida, F. psychrophilum, and Y. ruckeri, respectively. The assay was useful for the detection of the bacteria in artificially infected fish as well as in fish farm outbreaks. Results revealed that this multiplex PCR system permits a specific, sensitive, reproducible, and rapid method for the routine laboratory diagnosis of infections produced by these three bacteria. PMID:12324372

  4. Optimization of nested polymerase chain reaction assays for identification of Aeromonas salmonicida, Yersinia ruckeri and Flavobacterium psychrophilum

    USGS Publications Warehouse

    Taylor, P.W.; Winton, J.R.

    2002-01-01

    Nested polymerase chain reaction (PCR) assays were developed using first-round primers complementary to highly conserved regions within the bacterial 16S ribosomal RNA (rRNA) gene (universal eubacterial primers) and second-round primers specific for sequences within the 16S rRNA genes of Aeromonas salmonicida, Yersinia ruckeri, andFlavobacterium psychrophilum. Following optimization of the MgCl2 concentration and primer annealing temperature, PCR employing the universal eubacterial primers was used to amplify a 1,500-base-pair (bp) product visible in agarose gels stained with ethidium bromide. The calculated detection limit of this single-round assay was less than 1.4 × 104 colony-forming units (CFU) per reaction for all bacterial species tested. Single-round PCR using primer sets specific for A. salmonicida, Y. ruckeri, and F. psychrophilumamplified bands of 271, 575, and 1,100 bp, respectively, with detection limits of less than 1.4 × 104, 1.4 × 105, and 1.4 × 105 CFU per reaction. Using the universal eubacterial primers in the first round and the species-specific primer sets in the second round of nested PCR assays improved the detection ability by approximately four orders of magnitude to fewer than 14 CFU per sample for each of the three bacterial species. Such nested assays could be adapted to a wide variety of bacterial fish pathogens for which 16S sequences are available.

  5. Aeromonas salmonicida grown in vivo.

    PubMed Central

    Garduño, R A; Thornton, J C; Kay, W W

    1993-01-01

    The virulent fish pathogen Aeromonas salmonicida was rapidly killed in vivo when restricted inside a diffusion chamber implanted intraperitoneally in rainbow trout. After a period of regrowth, the survivors had acquired resistance to host-mediated bacteriolysis, phagocytosis, and oxidative killing, properties which were subsequently lost by growth in vitro. Resistance to bacteriolysis and phagocytosis was associated with a newly acquired capsular layer revealed by acidic polysaccharide staining and electron microscopy. This capsular layer shielded the underlying, regular surface array (S-layer) from immunogold labeling with a primary antibody to the S-layer protein. Resistance to oxidative killing was mediated by a mechanism not associated with the presence of the capsular layer. An attenuated vaccine strain of A. salmonicida grown in vivo failed to express the capsular layer. Consequently, the in vivo-grown cells of this attenuated strain remained as sensitive to bacteriolysis, and as avidly adherent to macrophages, as the in vitro-grown cells. The importance of these new virulence determinants and their relation to the known virulence factors of A. salmonicida are discussed. Images PMID:8359906

  6. Clustering subspecies of Aeromonas salmonicida using IS630 typing

    PubMed Central

    2013-01-01

    Background The insertion element IS630 found in Aeromonas salmonicida belongs to the IS630-Tc1-mariner superfamily of transposons. It is present in multiple copies and represents approximately half of the IS present in the genome of A. salmonicida subsp. salmonicida A449. Results By using High Copy Number IS630 Restriction Fragment Length Polymorphism (HCN-IS630-RFLP), strains of various subspecies of Aeromonas salmonicida showed conserved or clustering patterns, thus allowing their differentiation from each other. Fingerprints of A. salmonicida subsp. salmonicida showed the highest homogeneity while ‘atypical’ A. salmonicida strains were more heterogeneous. IS630 typing also differentiated A. salmonicida from other Aeromonas species. The copy number of IS630 in Aeromonas salmonicida ranges from 8 to 35 and is much lower in other Aeromonas species. Conclusions HCN-IS630-RFLP is a powerful tool for subtyping of A. salmonicida. The high stability of IS630 insertions in A. salmonicida subsp. salmonicida indicates that it might have played a role in pathoadaptation of A. salmonicida which has reached an optimal configuration in the highly virulent and specific fish pathogen A. salmonicida subsp. salmonicida. PMID:23406017

  7. Analysis of a ferric uptake regulator (Fur) knockout mutant in Aeromonas salmonicida subsp. salmonicida.

    PubMed

    Ebanks, Roger O; Goguen, Michel; Knickle, Leah; Dacanay, Andrew; Leslie, Andrew; Ross, Neil W; Pinto, Devanand M

    2013-03-23

    Aeromonas salmonicida subsp. salmonicida is the etiological agent of furunculosis; a serious infectious disease in aquaculture raised salmonids. Iron acquisition has been shown to be critical for the survival of pathogenic bacteria during the course of infection. Previous work has demonstrated that A. salmonicida expresses iron-repressible IROMP proteins, suggesting the presence of iron acquisition systems that are under the control of a ferric uptake regulator (Fur). In this study, the A. salmonicida fur has been sequenced and a fur deletion strain generated. The A. salmonicida fur gene has an open reading frame of 428 bp, coding for a protein of 143 amino acids, and with high homology to previously described Fur proteins. The Fur protein product had a 94% sequence identity and 96% sequence similarity to the Aeromonas hydrophila Fur protein product. Transcription of the A. salmonicida fur gene was not regulated by the iron status of the bacterium and is not autoregulated, as in Escherichia coli. Proteomic analysis of the A. salmonicida fur mutant, fails to repress iron-regulated outer membrane proteins in the presence of iron. The A. salmonicida fur::KO mutant shows significantly reduced pathogenicity compared to the wild-type parental strain. In addition, the A. salmonicida fur mutant provides an important tool for further investigation of the iron acquisition mechanisms utilized by A. salmonicida.

  8. 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.

  9. Aeromonas salmonicida subsp. salmonicida in the light of its type-three secretion system

    PubMed Central

    Vanden Bergh, Philippe; Frey, Joachim

    2014-01-01

    Aeromonas salmonicida subsp. salmonicida is an important pathogen in salmonid aquaculture and is responsible for the typical furunculosis. The type-three secretion system (T3SS) is a major virulence system. In this work, we review structure and function of this highly sophisticated nanosyringe in A. salmonicida. Based on the literature as well as personal experimental observations, we document the genetic (re)organization, expression regulation, anatomy, putative functional origin and roles in the infectious process of this T3SS. We propose a model of pathogenesis where A. salmonicida induces a temporary immunosuppression state in fish in order to acquire free access to host tissues. Finally, we highlight putative important therapeutic and vaccine strategies to prevent furunculosis of salmonid fish. PMID:24119189

  10. 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

  11. Effects of temperature on biochemical reactions and drug resistance of virulent and avirulent Aeromonas salmonicida

    USGS Publications Warehouse

    Hahnel, G.B.; Gould, R.W.

    1982-01-01

    Incubation temperatures of 11°, 18° and 28° did not substantially affect biochemical reactions of either virulent or avirulent forms of Aeromonas salmonicida subspecies salmonicida. The only change observed, amygdalin fermentation, was positive at 11° and 18° but negative at 28°C. Several isolates utilized sucrose, a characteristic not normally recognized for A. salmonicida subspecies salmonicida.Antimicrobial susceptibility screening indicated resistance to novobiocin increased at the higher incubation temperatures. Standardized drug sensitivity testing procedures and precise zone diameter interpretive standards for bacterial fish pathogens are needed.

  12. Triclosan Resistance in a Bacterial Fish Pathogen, Aeromonas salmonicida subsp. salmonicida, is Mediated by an Enoyl Reductase, FabV.

    PubMed

    Khan, Raees; Lee, Myung Hwan; Joo, Hae-Jin; Jung, Yong-Hoon; Ahmad, Shabir; Choi, Jin-Hee; Lee, Seon-Woo

    2015-04-01

    Triclosan, the widely used biocide, specifically targets enoyl-acyl carrier protein reductase (ENR) in the bacterial fatty acid synthesis system. Although the fish pathogen Aeromonas salmonicida subsp. salmonicida exhibits triclosan resistance, the nature of this resistance has not been elucidated. Here, we aimed to characterize the triclosan resistance of A. salmonicida subsp. salmonicida causing furunculosis. The fosmid library of triclosan-resistant A. salmonicida subsp. salmonicida was constructed to select a fosmid clone showing triclosan resistance. With the fosmid clone showing triclosan resistance, a subsequent secondary library search resulted in the selection of subclone pTSR-1. DNA sequence analysis of pTSR-1 revealed the presence of a chromosomal-borne fabV-encoding ENR homolog. The ENR of A. salmonicida (FabVas) exhibited significant homology with previously known FabV, including the catalytic domain YX(8)K. fabVas introduction into E. coli dramatically increased its resistance to triclosan. Heterologous expression of FabVas might functionally replace the triclosan-sensitive FabI in vivo to confer E. coli with triclosan resistance. A genome-wide search for fabVas homologs revealed the presence of an additional fabV gene (fabVas2) paralog in A. salmonicida strains and the fabVas orthologs from other gram-negative fish pathogens. Both of the potential FabV ENRs expressed similarly with or without triclosan supplement. This is the first report about the presence of two potential FabV ENRs in a single pathogenic bacterium. Our result suggests that triclosan-resistant ENRs are widely distributed in various bacteria in nature, and the wide use of this biocide can spread these triclosan-tolerant ENRs among fish pathogens and other pathogenic bacteria.

  13. Two Catechol Siderophores, Acinetobactin and Amonabactin, Are Simultaneously Produced by Aeromonas salmonicida subsp. salmonicida Sharing Part of the Biosynthetic Pathway.

    PubMed

    Balado, Miguel; Souto, Alba; Vences, Ana; Careaga, Valeria P; Valderrama, Katherine; Segade, Yuri; Rodríguez, Jaime; Osorio, Carlos R; Jiménez, Carlos; Lemos, Manuel L

    2015-12-18

    The iron uptake mechanisms based on siderophore synthesis used by the fish pathogen Aeromonas salmonicida subsp. salmonicida are still not completely understood, and the precise structure of the siderophore(s) is unknown. The analysis of genome sequences revealed that this bacterium possesses two gene clusters putatively involved in the synthesis of siderophores. One cluster is a candidate to encode the synthesis of acinetobactin, the siderophore of the human pathogen Acinetobacter baumannii, while the second cluster shows high similarity to the genes encoding amonabactin synthesis in Aeromonas hydrophila. Using a combination of genomic analysis, mutagenesis, biological assays, chemical purification, and structural determination procedures, here we demonstrate that most A. salmonicida subsp. salmonicida strains produce simultaneously the two siderophores, acinetobactin and amonabactin. Interestingly, the synthesis of both siderophores relies on a single copy of the genes encoding the synthesis of the catechol moiety (2,3-dihydroxybenzoic acid) and on one encoding a phosphopantetheinyl transferase. These genes are present only in the amonabactin cluster, and a single mutation in any of them abolishes production of both siderophores. We could also demonstrate that some strains, isolated from fish raised in seawater, produce only acinetobactin since they present a deletion in the amonabactin biosynthesis gene amoG. Our study represents the first evidence of simultaneous production of acinetobactin and amonabactin by a bacterial pathogen and reveals the plasticity of bacterial genomes and biosynthetic pathways. The fact that the same siderophore is produced by unrelated pathogens highlights the importance of these systems and their interchangeability between different bacteria.

  14. Draft Genome Sequence of Pseudomonas fluorescens ML11A, an Endogenous Strain from Brook Charr with Antagonistic Properties against Aeromonas salmonicida subsp. salmonicida

    PubMed Central

    Charette, Steve J.; Derome, Nicolas

    2017-01-01

    ABSTRACT Pseudomonas fluorescens ML11A, isolated from brook charr, showed a strong in vitro inhibitory effect against Aeromonas salmonicida subsp. salmonicida, a bacterial fish pathogen. Its genome harbors gene clusters for siderophore and bacteriocin biosynthesis and shares 99% whole-genome identity with P. fluorescens A506, a biological control strain used in agriculture. PMID:28254983

  15. Diversity and Homogeneity among Small Plasmids of Aeromonas salmonicida subsp. salmonicida Linked with Geographical Origin

    PubMed Central

    Attéré, Sabrina A.; Vincent, Antony T.; Trudel, Mélanie V.; Chanut, Romain; Charette, Steve J.

    2015-01-01

    Furunculosis, which is caused by Aeromonas salmonicida subsp. salmonicida, is a major salmonid disease in fish farms worldwide. Several plasmids found in this bacterium confer phenotypes such drug resistance and virulence. Small plasmids (pAsa1, pAsa2, pAsa3, and pAsal1) related to ColE1- and ColE2-type replicons are usually present in its normal plasmidome. In the present study, with the objective to investigate if these plasmids display particularities related to the origin of the isolates bearing them, a total of 153 isolates, including 78 new and 75 previously described, were analyzed for the presence of small plasmids by PCR and DNA restriction fragment profiling. A geographical dichotomy between Canadian and European isolates for their propensity to do not have pAsa3 or pAsal1 was found. In addition, the genotyping analysis led to the identification of two European isolates harboring an unusual pAsal1. An investigation by next-generation sequencing (NGS) of these two isolates shed light on two pAsal1 variants (pAsal1C and pAsal1D). As with pAsal1B, another pAsal1 variant previously described, these two new variants bore a second insertion sequence (ISAS5) in addition to the usual ISAS11. The characterization of these variants suggested that they could predominate over the wild-type pAsal1 in stressful conditions such as growth at temperatures of 25°C and above. To obtain a comprehensive portrait of the mutational pressure on small plasmids, 26 isolates whose DNA had been sequenced by NGS were investigated. pAsa3 and pAsal1 were more prone to mutations than pAsa1 and pAsa2, especially in the mobA gene, which encodes a relaxase and a primase. Lastly, the average copy number of each plasmid per cell was assessed using raw sequencing data. A clear trend with respect to the relative proportion per cell of each plasmid was identified. Our large-scale study revealed a geographical dichotomy in small plasmid repertoire in addition to a clear trend for pAsa3 and p

  16. The mosaic architecture of Aeromonas salmonicida subsp. salmonicida pAsa4 plasmid and its consequences on antibiotic resistance

    PubMed Central

    Tanaka, Katherine H.; Vincent, Antony T.; Trudel, Mélanie V.; Paquet, Valérie E.; Frenette, Michel

    2016-01-01

    Aeromonas salmonicida subsp. salmonicida, the causative agent of furunculosis in salmonids, is an issue especially because many isolates of this bacterium display antibiotic resistances, which limit treatments against the disease. Recent results suggested the possible existence of alternative forms of pAsa4, a large plasmid found in A. salmonicida subsp. salmonicida and bearing multiple antibiotic resistance genes. The present study reveals the existence of two newly detected pAsa4 variants, pAsa4b and pAsa4c. We present the extensive characterization of the genomic architecture, the mobile genetic elements and the antimicrobial resistance genes of these plasmids in addition to the reference pAsa4 from the strain A449. The analysis showed differences between the three architectures with consequences on the content of resistance genes. The genomic plasticity of the three pAsa4 variants could be partially explained by the action of mobile genetic elements like insertion sequences. Eight additional isolates from Canada and Europe that bore similar antibiotic resistance patterns as pAsa4-bearing strains were genotyped and specific pAsa4 variants could be attributed to phenotypic profiles. pAsa4 and pAsa4c were found in Europe, while pAsa4b was found in Canada. In accordance with their content in conjugative transfer genes, only pAsa4b and pAsa4c can be transferred by conjugation in Escherichia coli. The plasticity of pAsa4 variants related to the acquisition of antibiotic resistance indicates that these plasmids may pose a threat in terms of the dissemination of antimicrobial-resistant A. salmonicida subsp. salmonicida bacteria. PMID:27812409

  17. Comparative genomics profiling of clinical isolates of Aeromonas salmonicida using DNA microarrays

    PubMed Central

    Nash, John HE; Findlay, Wendy A; Luebbert, Christian C; Mykytczuk, Oksana L; Foote, Simon J; Taboada, Eduardo N; Carrillo, Catherine D; Boyd, Jessica M; Colquhoun, Duncan J; Reith, Michael E; Brown, Laura L

    2006-01-01

    Background Aeromonas salmonicida has been isolated from numerous fish species and shows wide variation in virulence and pathogenicity. As part of a larger research program to identify virulence genes and candidates for vaccine development, a DNA microarray was constructed using a subset of 2024 genes from the draft genome sequence of A. salmonicida subsp. salmonicida strain A449. The microarray included genes encoding known virulence-associated factors in A. salmonicida and homologs of virulence genes of other pathogens. We used microarray-based comparative genomic hybridizations (M-CGH) to compare selected A. salmonicida sub-species and other Aeromonas species from different hosts and geographic locations. Results Results showed variable carriage of virulence-associated genes and generally increased variation in gene content across sub-species and species boundaries. The greatest variation was observed among genes associated with plasmids and transposons. There was little correlation between geographic region and degree of variation for all isolates tested. Conclusion We have used the M-CGH technique to identify subsets of conserved genes from amongst this set of A. salmonicida virulence genes for further investigation as potential vaccine candidates. Unlike other bacterial characterization methods that use a small number of gene or DNA-based functions, M-CGH examines thousands of genes and/or whole genomes and thus is a more comprehensive analytical tool for veterinary or even human health research. PMID:16522207

  18. 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.

  19. The Aeromonas salmonicida Lipopolysaccharide Core from Different Subspecies: The Unusual subsp. pectinolytica.

    PubMed

    Merino, Susana; Tomás, Juan M

    2016-01-01

    Initial hydridization tests using Aeromonas salmonicida typical and atypical strains showed the possibility of different lipopolysaccharide (LPS) outer cores among these strains. By chemical structural analysis, LPS-core SDS-PAGE gel migration, and functional and comparative genomics we demonstrated that typical A. salmonicida (subsp. salmonicida) strains and atypical subsp. masoucida and probably smithia strains showed the same LPS outer core. A. salmonicida subsp. achromogenes strains show a similar LPS outer core but lack one of the most external residues (a galactose linked α1-6 to heptose), not affecting the O-antigen LPS linkage. A. salmonicida subsp. pectinolytica strains show a rather changed LPS outer core, which is identical to the LPS outer core from the majority of the A. hydrophila strains studied by genomic analyses. The LPS inner core in all tested A. salmonicida strains, typical and atypical, is well-conserved. Furthermore, the LPS inner core seems to be conserved in all the Aeromonas (psychrophilic or mesophilic) strains studied by genomic analyses.

  20. Development of a SYBR green I real-time PCR assay for specific identification of the fish pathogen Aeromonas salmonicida subspecies salmonicida.

    PubMed

    Fernández-Álvarez, Clara; González, Santiago F; Santos, Ysabel

    2016-12-01

    A SYBR Green I real-time polymerase chain reaction protocol for specific detection of the fish pathogen Aeromonas salmonicida subsp. salmonicida was developed and validated for rapid diagnosis of typical furunculosis. The sequence of the aopO gene of A. salmonicida subsp. salmonicida, which encodes for a serine/threonine protein kinase linked to virulence, was chosen for primer design. The selected primers amplified a 119-bp internal fragment of the aopO gene. The specificity test proved that 100 % (40/40) of the A. salmonicida subsp. salmonicida strains tested showed a positive amplification with subspecies-specific melting temperatures (Tm) of 80.75 ± 0.35 °C. Atypical A. salmonicida subspecies and other non-related bacterial fish pathogens did not amplify or showed unspecific melting profiles, except for one strain of A. salmonicida subsp. achromogenes and one strain of A. salmonicida subsp. smithia. The detection sensitivity was 21 fg of purified bacterial DNA per reaction, corresponding to 1-2 bacterial cells and 6-60 bacteria per reaction for seeded kidney and blood. The assay was highly reproducible with low variation coefficient values for intra-run and inter-run assays. The assay also allowed the specific detection of A. salmonicida subsp. salmonicida in tissues of fish naturally and experimentally infected. No amplification was detected when tissues from healthy fish or fish affected by other diseases were tested. The SYBR Green real-time PCR and melt curve analysis developed in this study is a rapid and accurate method for the specific identification of A. salmonicida subsp. salmonicida isolates and its detection on tissues of fish affected by furunculosis.

  1. Subunit vaccine candidates against Aeromonas salmonicida in rainbow trout Oncorhynchus mykiss

    PubMed Central

    Jørgensen, Louise von Gersdorff; Skov, Jakob; Chettri, Jiwan Kumar; Holm Mattsson, Andreas; Dalsgaard, Inger; Kania, Per Walter; Buchmann, Kurt

    2017-01-01

    Aeromonas salmonicida subsp. salmonicida is the etiological agent of furunculosis and a major fish health problem in salmonid aquaculture worldwide. Injection vaccination with commercial mineral oil-adjuvanted bacterin vaccines has been partly successful in preventing the disease but in Danish rainbow trout (Oncorhynchus mykiss, Walbaum) aquaculture furunculosis outbreaks still occur. In this study we tested the efficacy of experimental subunit vaccines against A. salmonicida infection in rainbow trout. We utilized in silico screening of the proteome of A. salmonicida subsp. salmonicida strain A449 and identified potential protective protein antigens that were tested by in vivo challenge trial. A total of 14 proteins were recombinantly expressed in Escherichia coli and prepared in 3 different subunit vaccine combinations to immunize 3 groups of rainbow trout by intraperitoneal (i.p.) injection. The fish were exposed to virulent A. salmonicida 7 weeks after immunization. To assess the efficacy of the subunit vaccines we evaluated the immune response in fish after immunization and challenge infection by measuring the antibody levels and monitoring the survival of fish in different groups. The survival of fish at 3 weeks after challenge infection showed that all 3 groups of fish immunized with 3 different protein combinations exhibited significantly lower mortalities (17–30%) compared to the control groups (48% and 56%). The ELISA results revealed significantly elevated antibody levels in fish against several protein antigens, which in some cases were positively correlated to the survival. PMID:28182704

  2. The impact of quorum sensing on the virulence of Aeromonas hydrophila and Aeromonas salmonicida towards burbot (Lota lota L.) larvae.

    PubMed

    Natrah, F M I; Alam, Md Iftakharul; Pawar, Sushant; Harzevili, A Shiri; Nevejan, Nancy; Boon, Nico; Sorgeloos, Patrick; Bossier, Peter; Defoirdt, Tom

    2012-09-14

    In this study, the link between quorum sensing in Aeromonas spp. and its virulence towards burbot (Lota lota) was investigated. High mortality occurred in burbot juveniles challenged with Aeromonas salmonicida HN-00, but not in juveniles challenged with Aeromonas hydrophila AH-1N. Meanwhile, both A. hydrophila AH-1N and A. salmonicida HN-00 were virulent towards larvae. The effect of quorum sensing on the virulence of A. hydrophila AH-1N towards burbot larvae was further investigated using quorum sensing mutants (N-(butyryl)-L-homoserine lactone production and receptor mutants). Challenge with these mutants resulted in higher survival of burbot larvae when compared to challenge with the wild type, and the addition of the signal molecule N-butyryl-L-homoserine lactone restored the virulence of the quorum sensing production mutant. Moreover, quorum sensing inhibitors protected the burbot larvae from both Aeromonas strains. Finally, the freshwater micro-algae Chlorella saccharophila and Chlamydomonas reinhardtii, which are able to interfere with quorum sensing, also protected burbot from the pathogens. However, QS interference was unlikely to be the only mechanism. This study revealed that the virulence of Aeromonas spp. towards burbot is regulated by quorum sensing and that quorum sensing inhibitors and micro-algae are promising biocontrol agents.

  3. Precipitating antibody against Aeromonas salmonicida in serums of inbred albino Rainbow Trout (Salmo gairdneri)

    USGS Publications Warehouse

    Anderson, Douglas P.; Klontz, George W.

    1970-01-01

    Precipitins in albino rainbow trout serums were demonstrated by gel diffusion after a single parenteral exposure to the soluble antigens of Aeromonas salmonicida. The fraction of the serum containing antibody activity against the presented antigens was shown by immunoelectrophoresis to be in the nonmigrating region. This corresponded to the beta-2 fraction of rabbit serum. An antibody-containing component comparable with rabbit gamma globulin was not detected.

  4. Aeromonas salmonicida Ati2 is an effector protein of the type three secretion system.

    PubMed

    Dallaire-Dufresne, Stéphanie; Barbeau, Xavier; Sarty, Darren; Tanaka, Katherine H; Denoncourt, Alix M; Lagüe, Patrick; Reith, Michael E; Charette, Steve J

    2013-09-01

    The bacterium Aeromonas salmonicida, a fish pathogen, uses the type three secretion system (TTSS) to inject effector proteins into host cells to promote the infection. The study of the genome of A. salmonicida has revealed the existence of Ati2, a potential TTSS effector protein. In the present study, a structure-function analysis of Ati2 has been done to determine its role in the virulence of A. salmonicida. Biochemical assays revealed that Ati2 is secreted into the medium in a TTSS-dependent manner. Protein sequence analyses, molecular modelling and biochemical assays demonstrated that Ati2 is an inositol polyphosphate 5-phosphatase, which hydrolyses PtdIns(4,5)P2 and PtdIns(3,4,5)P3 in a way similar to VPA0450, a protein from Vibrio parahaemolyticus having high sequence similarity with Ati2. Mutants of Ati2 with altered amino acids at two different locations in the catalytic site displayed no phosphatase activity. Wild-type and mutant forms of Ati2 were cloned into expression systems for Dictyostelium discoideum, a soil amoeba used as an alternative host to study A. salmonicida virulence. Expression tests allowed us to demonstrate that Ati2 is toxic for the host cell in a catalytic-dependent manner. Finally, this study demonstrated the existence of a new TTSS effector protein in A. salmonicida.

  5. Detection and quantification of Aeromonas salmonicida in fish tissue by real-time PCR.

    PubMed

    Bartkova, S; Kokotovic, B; Skall, H F; Lorenzen, N; Dalsgaard, I

    2017-02-01

    Furunculosis, a septicaemic infection caused by the bacterium Aeromonas salmonicida subsp. salmonicida, currently causes problems in Danish seawater rainbow trout production. Detection has mainly been achieved by bacterial culture, but more rapid and sensitive methods are needed. A previously developed real-time PCR assay targeting the plasmid encoded aopP gene of A. salmonicida was, in parallel with culturing, used for the examination of five organs of 40 fish from Danish freshwater and seawater farms. Real-time PCR showed overall a higher frequency of positives than culturing (65% of positive fish by real-time PCR compared to 30% by a culture approach). Also, no real-time PCR-negative samples were found positive by culturing. A. salmonicida was detected by real-time PCR, though not by culturing, in freshwater fish showing no signs of furunculosis, indicating possible presence of carrier fish. In seawater fish examined after an outbreak and antibiotics treatment, real-time PCR showed the presence of the bacterium in all examined organs (1-482 genomic units mg(-1) ). With a limit of detection of 40 target copies (1-2 genomic units) per reaction, a high reproducibility and an excellent efficiency, the present real-time PCR assay provides a sensitive tool for the detection of A. salmonicida.

  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. 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

  8. The impact of Aeromonas salmonicida infection on innate immune parameters of Atlantic salmon (Salmo salar L).

    PubMed

    Du, Yishuai; Yi, Mengmeng; Xiao, Peng; Meng, Lingjie; Li, Xian; Sun, Guoxiang; Liu, Ying

    2015-05-01

    Enzyme activities and gene expression of a number of innate immune parameters in the serum, mucus and skin of Atlantic salmon (Salmo salar) were investigated after challenge with a pathogenic strain of Aeromonas salmonicida (A. salmonicida). Fish were injected in the dorsal muscle with either 100 μl bacterium solution, about 3.05 × 10(7) CFU/ml A. salmonicida, or 100 μl 0.9% NaCl (as control group) and tissue samples were collected at days 0, 2, 4 and 6 post-injection. Lysozyme (LSZ) and alkaline phosphatase (AKP) activities in serum, mucus and skin, and LSZ and AKP mRNA expression in skin of the challenged fish were higher than those of the control at most of the experimental time, with significant differences at several time points (P < 0.05), indicating the involvement of LSZ and AKP in the innate immunity of Atlantic salmon to A. salmonicida. Superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities in mucus and skin, along with the SOD, POD and CAT mRNA expression in skin significantly decreased at day 4 and 6, indicating the decreased antioxidant capacity of the challenged fish. Glutamate pyruvate transaminase (GPT) and glutamic oxalacetic transaminase (GOT) activities in serum, mucus and skin of the challenged group were all higher than those of the control after the injection, and at several time points significant differences were found between the two groups, suggesting organs of fish were impaired after the pathogen infection. The changes of the GPT and GOT activities could be used as potential biomarkers for the impairment of physiological functions caused by the pathogen infection. Identified biomarkers of the immune responses will contribute to the early-warning system of the disease. So this study will not only provide a theoretical basis for vaccine development, but also provide basic data for the establishment of early warning systems for diseases caused by A. salmonicida in Atlantic salmon rearing.

  9. Evaluation of commercially prepared transport systems for nonlethal detection of Aeromonas salmonicida in salmonid fish

    USGS Publications Warehouse

    Cipriano, R.C.; Bullock, G.L.

    2001-01-01

    In vitro studies indicated that commercially prepared transport systems containing Amies, Stuart's, and Cary-Blair media worked equally well in sustaining the viability of the fish pathogen Aeromonas salmonicida, which causes furunculosis. The bacterium remained viable without significant increase or decrease in cell numbers for as long as 48 h of incubation at 18-20??C in Stuart's transport medium; consequently, obtaining mucus samples in such tubes were comparable to on-site detection of A. salmonicida by dilution plate counts on Coomassie Brilliant Blue agar. In three different assays of 100 samples of mucus from Atlantic salmon Salmo salar infected subclinically with A. salmonicida, dilution counts conducted on-site proved more reliable for detecting the pathogen than obtaining the samples in the transport system. In the on-site assays, dilution counts detected the pathogen in 34, 41, and 22 samples, whereas this was accomplished in only 15, 15, and 3 of the respective samples when the transport system was used. In an additional experiment, Arctic char Salvelinus alpinus sustaining a frank epizootic of furunculosis were sampled similarly. Here, too, dilution counts were more predictive of the prevalence of A. salmonicida and detected the pathogen in 46 mucus samples; in comparison, only 6 samples collected by using the transport system were positive. We also observed that the transport system supported the growth of the normal mucus bacterial flora. Particularly predominant among these were motile aeromonads and Pseudomonas fluorescens. In studies of mixed culture growth, two representatives of both of the latter genera of bacteria outgrew A. salmonicida - in some cases, to the total exclusion of the pathogen itself.

  10. Interaction of the fish pathogen Aeromonas salmonicida with rainbow trout macrophages.

    PubMed Central

    Garduño, R A; Kay, W W

    1992-01-01

    A procedure was developed to culture rainbow trout macrophages (M phi) on supported glass coverslips. Using this method and a variety of well-characterized Aeromonas salmonicida strains with normal or altered cell surfaces, we investigated the role of this unusual bacterial surface in the bacterium-M phi interaction. An intact crystalline protein array, the A-layer, mediated adherence of A. salmonicida cells to M phi even in the absence of opsonins. In contrast, unopsonized cells of an A-layer-negative (A-) mutant with a smooth lipopolysaccharide (LPS) layer were unable to interact with M phi. However, this ability was recovered when the A-layer was reconstituted onto the smooth LPS surface of these A- LPS+ cells. Two A. salmonicida mutants possessing the A-layer in different disorganized states had a reduced ability to interact with M phi. A+ cells grown under calcium limitation produced A-layers locked into an alternative conformation which mediated the highest levels of M phi association in the absence of opsonins or any other surface coating. Coating A+ cells with hemin greatly increased their levels of M phi association, and bacterial cells grown on trout blood agar plates also had a dramatic increase in their ability to interact with M phi. Only A+ A. salmonicida cells were highly cytotoxic to trout M phi, especially after being coated with hemin, presumably due to a more focused targeting of the bacterial cell onto the M phi surface and/or into the intracellular regions of the M phi. Images PMID:1398975

  11. Infection routes of Aeromonas salmonicida in rainbow trout monitored in vivo by real-time bioluminescence imaging.

    PubMed

    Bartkova, S; Kokotovic, B; Dalsgaard, I

    2017-01-01

    Recent development of imaging tools has facilitated studies of pathogen infections in vivo in real time. This trend can be exemplified by advances in bioluminescence imaging (BLI), an approach that helps to visualize dissemination of pathogens within the same animal over several time points. Here, we employ bacterial BLI for examining routes of entry and spread of Aeromonas salmonicida susbp. salmonicida in rainbow trout. A virulent Danish A. salmonicida strain was tagged with pAKgfplux1, a dual-labelled plasmid vector containing the mutated gfpmut3a gene from Aequorea victoria and the luxCDABE genes from the bacterium Photorhabdus luminescens. The resulting A. salmonicida transformant exhibited growth properties and virulence identical to the wild-type A. salmonicida, which made it suitable for an experimental infection, mimicking natural conditions. Fish were infected with pAKgfplux1 tagged A. salmonicida via immersion bath. Colonization and subsequent tissue dissemination was followed over a 24-h period using the IVIS spectrum imaging workstation. Results suggest the pathogen's colonization sites are the dorsal and pectoral fin and the gills, followed by a progression through the internal organs and an ensuing exit via the anal opening. This study provides a tool for visualizing colonization of A. salmonicida and other bacterial pathogens in fish.

  12. Identification of the Ferric-Acinetobactin Outer Membrane Receptor in Aeromonas salmonicida subsp. salmonicida and Structure-Activity Relationships of Synthetic Acinetobactin Analogues.

    PubMed

    Balado, Miguel; Segade, Yuri; Rey, Diego; Osorio, Carlos R; Rodríguez, Jaime; Lemos, Manuel L; Jiménez, Carlos

    2017-02-17

    Aeromonas salmonicida subsp. salmonicida, the causative agent of furunculosis in several fish species, produces acinetobactin and amonabactin as siderophores. In a previous study, we chemically characterized these siderophores and proposed a biosynthetic pathway based on genetic analysis. However, the internalization mechanisms of ferric-acinetobactin and ferric-amonabactin remain largely unknown. In the present study, we demonstrate that the outer membrane protein FstB is the ferric-acinetobactin receptor in A. salmonicida since an fstB defective mutant is unable to grow under iron limitation and does not use acinetobactin as an iron source. In order to study the effect that structural changes in acinetobactin have on its siderophore activity, a collection of acinetobactin-based analogues was synthesized, including its enantiomer and four demethylated derivatives. The biological activity of these analogues on an fstB(+) strain compared to an fstB(-) strain allowed structure-activity relationships to be elucidated. We found a lack of enantiomer preference on the siderophore activity of acinetobactin over A. salmonicida or on the molecular recognition by FstB protein receptor. In addition, it was observed that A. salmonicida could not use acinetobactin analogues when imidazole or a similar heterocyclic ring was absent from the structure. Surprisingly, removal of the methyl group at the isoxazolidinone ring induced a higher biological activity, thus suggesting alternative route(s) of entry into the cell that must be further investigated. It is proposed that some of the synthetic acinetobactin analogues described here could be used as starting points in the development of novel drugs against A. salmonicida and probably against other acinetobactin producers like the human pathogen Acinetobacter baumannii.

  13. Quarantine of Aeromonas salmonicida-harboring ebonyshell mussels (Fusconaia ebena) prevents transmission of the pathogen to brook trout (Salvelinus fontinalis)

    USGS Publications Warehouse

    Starliper, C.E.

    2005-01-01

    Furunculosis, caused by the bacterium Aeromonas salmonicida, was artificially induced in brook trout (Salvelinus fontinalis) in an experimental tank. Ebonyshells (Fusconaia ebena) were placed to cohabit with these fish to acquire the pathogen through siphoning. After 2 wk of cohabitation, 10 of the mussels were assayed by bacterial culture and all were found to harbor A. salmonicida. The mean cell count from soft tissue homogenates was 1.84 ?? 105 cfu/g, which comprised an average 14.41% of the total bacteria isolated from tissues. From the fluids, a mean of 2.84 ?? 105 A. salmonicida cfu/mL was isolated, which comprised an average of 17.29% of the total bacterial flora. The mussels were removed from the cohabitation tank and distributed equally among five previously disinfected tanks, 35 per tank. The F. ebena in each tank were allowed to depurate A. salmonicida for various durations: 1, 5, 10, 15 or 30 days. After each group had depurated for their assigned time, 10 were assayed for bacteria, tank water was tested, and 20 pathogen-free bioindicator brook trout were added to cohabit with the remaining mussels. Depuration was considered successful if A. salmonicida was not isolated from tank water or the mussels, and there was no infection or mortality to bioindicator fish. After 1 day of depuration, A. salmonicida was not isolated from the soft tissues; however, it was isolated from one of the paired fluids (10% prevalence). The tank water tested positive, and the bioindicator fish became infected and died. From the 5-day depuration group, A. salmonicida was not isolated from soft tissues, but was isolated from three fluids (30%; mean = 1.56 ?? 102 cfu/mL). Tank water from the 5-day group was negative, and there was no mortality among the bioindicator fish. However, A. salmonicida was isolated from 2 of 20 fish at the end of the 14-day observation period. One F. ebena fluid sample was positive for A. salmonicida from the 10-day depuration group, but none of the

  14. In vitro studies of Lactobacillus delbrueckii subsp. lactis in Atlantic salmon (Salmo salar L.) foregut: tissue responses and evidence of protection against Aeromonas salmonicida subsp. salmonicida epithelial damage.

    PubMed

    Salinas, Irene; Myklebust, Reidar; Esteban, Maria Angeles; Olsen, Rolf Erik; Meseguer, José; Ringø, Einar

    2008-04-01

    Probiotic bacteria increase the host health status and protect mucosal tissue against pathogen-caused damage in mammalian models. Using an in vitro (intestinal sac) method this study aimed to address (a) the in vitro ability of Lactobacillus delbrueckii subsp. lactis to remain in the gastrointestinal tract of Atlantic salmon (Salmo salar L.) and (b) its ability to prevent cellular damage caused by successive incubation with Aeromonas salmonicida subsp. salmonicida the causative agent of furunculosis. Short in vitro incubation of salmon foregut with (TRITC)-labelled L. delbrueckii subsp. lactis showed that the probiont was able to colonize the enterocyte surface as studied by confocal microscopy. Furthermore, foregut incubated with the probiotic bacteria only, resulted in a healthy intestinal barrier whereas exposure to A. salmonicida disrupted its integrity. However, pre-treatment of salmon intestine with L. delbrueckii subsp. lactis prevented Aeromonas damaging effects. These results are promising in the context of the use of non-autochthonous probiotic bacteria as prophylactic agents against fish bacterial infections in the gastrointestinal tract.

  15. Occurrence and significance of atypical Aeromonas salmonicida in non-salmonid and salmonid fish species: a review.

    PubMed

    Wiklund, T; Dalsgaard, I

    1998-02-26

    Bacterial strains of Aeromonas salmonicida included in the recognized subsp. acromogenes, subsp. masoucida, and subsp. smithia in addition to the large number of strains not included in any of the described subspecies are referred to as atypical A. salmonicida. The atypical strains form a very heterogeneous group with respect to biochemical characteristics, growth conditions, and production of extracellular proteasess. Consequently, the present taxonomy of the species A. salmonicida is rather ambiguous. Atypical A. salmonicida has been isolated from a wide range of cultivated and wild fish species, non-salmonids as well as salmonids, inhabiting fresh water, brackish water and marine environments in northern and central Europe, South Africa, North America, Japan and Australia. In non-salmonid fish species, infections with atypical strains often manifest themselves as superficial skin ulcerations. The best known diseases associated with atypical A. salmonicida are carp Cyprinus carpio erythrodermatitis, goldfish Carassius auratus ulcer disease, and ulcer disease of flounder Platichthys flesus, but atypical strains are apparently involved in more disease outbreaks than previously suspected. Macroscopical and microscopical studies of ulcerated fish indicate internal organs are infrequently invaded by atypical A. salmonicida. This view is supported by the fact that atypical strains are irregularly isolated from visceral organs of ulcerated fish. High mortality caused by atypical A. salmonicida has been observed in populations of wild non-salmonids and farmed salmonids, although the association between the mortality in the wild fish stocks and atypical A. salmonicida has not always been properly assessed. In injection experiments the pathogenicity of the atypical strains examined showed large variation. An extacellular A-layer has been detected in different atypical strains, but virulence mechanisms different from those described for (typical) A. salmonicida subsp

  16. Differential partition of virulent Aeromonas salmonicida and attenuated derivatives possessing specific cell surface alterations in polymer aqueous-phase systems

    NASA Technical Reports Server (NTRS)

    Van Alstine, J. M.; Trust, T. J.; Brooks, D. E.

    1986-01-01

    Two-polymer aqueous-phase systems in which partitioning of biological matter between the phases occurs according to surface properties such as hydrophobicity, charge, and lipid composition are used to compare the surface properties of strains of the fish pathogen Aeromonas salmonicida. The differential ability of strains to produce a surface protein array crucial to their virulence, the A layer, and to produce smooth lipopolysaccharide is found to be important in the partitioning behavior of Aeromonas salmonicida. The presence of the A layer is shown to decrease the surface hydrophilicity of the pathogen, and to increase specifically its surface affinity for fatty acid esters of polyethylene glycol. The method has application to the analysis of surface properties crucial to bacterial virulence, and to the selection of strains and mutants with specific surface characteristics.

  17. QTL detection for Aeromonas salmonicida resistance related traits in turbot (Scophthalmus maximus)

    PubMed Central

    2011-01-01

    Background Interactions between fish and pathogens, that may be harmless under natural conditions, often result in serious diseases in aquaculture systems. This is especially important due to the fact that the strains used in aquaculture are derived from wild strains that may not have had enough time to adapt to new disease pressures. The turbot is one of the most promising European aquaculture species. Furunculosis, caused by the bacterium Aeromonas salmonicida, produces important losses to turbot industry. An appealing solution is to achieve more robust broodstock, which can prevent or diminish the devastating effects of epizooties. Genomics strategies have been developed in turbot to look for candidate genes for resistance to furunculosis and a genetic map with appropriate density to screen for genomic associations has been also constructed. In the present study, a genome scan for QTL affecting resistance and survival to A. salmonicida in four turbot families was carried out. The objectives were to identify consistent QTL using different statistical approaches (linear regression and maximum likelihood) and to locate the tightest associated markers for their application in genetic breeding strategies. Results Significant QTL for resistance were identified by the linear regression method in three linkage groups (LGs 4, 6 and 9) and for survival in two LGs (6 and 9). The maximum likelihood methodology identified QTL in three LGs (5, 6 and 9) for both traits. Significant association between disease traits and genotypes was detected for several markers, some of them explaining up to 17% of the phenotypic variance. We also identified candidate genes located in the detected QTL using data from previously mapped markers. Conclusions Several regions controlling resistance to A. salmonicida in turbot have been detected. The observed concordance between different statistical methods at particular linkage groups gives consistency to our results. The detected associated

  18. Aeromonas salmonicida Binds Differentially to Mucins Isolated from Skin and Intestinal Regions of Atlantic Salmon in an N-Acetylneuraminic Acid-Dependent Manner

    PubMed Central

    Padra, János T.; Sundh, Henrik; Jin, Chunsheng; Karlsson, Niclas G.; Sundell, Kristina

    2014-01-01

    Aeromonas salmonicida subsp. salmonicida infection, also known as furunculosis disease, is associated with high morbidity and mortality in salmonid aquaculture. The first line of defense the pathogen encounters is the mucus layer, which is predominantly comprised of secreted mucins. Here we isolated and characterized mucins from the skin and intestinal tract of healthy Atlantic salmon and studied how A. salmonicida bound to them. The mucins from the skin, pyloric ceca, and proximal and distal intestine mainly consisted of mucins soluble in chaotropic agents. The mucin density and mucin glycan chain length from the skin were lower than were seen with mucin from the intestinal tract. A. salmonicida bound to the mucins isolated from the intestinal tract to a greater extent than to the skin mucins. The mucins from the intestinal regions had higher levels of sialylation than the skin mucins. Desialylating intestinal mucins decreased A. salmonicida binding, whereas desialylation of skin mucins resulted in complete loss of binding. In line with this, A. salmonicida also bound better to mammalian mucins with high levels of sialylation, and N-acetylneuraminic acid appeared to be the sialic acid whose presence was imperative for binding. Thus, sialylated structures are important for A. salmonicida binding, suggesting a pivotal role for sialylation in mucosal defense. The marked differences in sialylation as well as A. salmonicida binding between the skin and intestinal tract suggest interorgan differences in the host-pathogen interaction and in the mucin defense against A. salmonicida. PMID:25287918

  19. Effect of a phytogenic feed additive on the susceptibility of Onchorhynchus mykiss to Aeromonas salmonicida.

    PubMed

    Menanteau-Ledouble, S; Krauss, I; Santos, G; Fibi, S; Weber, B; El-Matbouli, M

    2015-06-29

    In recent years, feed additives have increasingly been adopted by the aquaculture industry. These supplements not only offer an alternative to antibiotics but have also been linked to enhanced growth performance. However, the literature is still limited and provides contradictory information on their effectiveness. This is mainly due to the wide variety of available products and their complex mechanisms of action. Phytogenic feed additives have been shown to have antimicrobial effects and can improve growth performance. In the present study, we investigated the susceptibility of several fish pathogenic bacteria to a phytogenic essential oil product in vitro. In addition, we determined the protective effect of a commercial phytogenic feed additive containing oregano, anis and citrus oils on the resistance of rainbow trout Oncorhynchus mykiss to infection by Aeromonas salmonicida. The bacterium was administered through 3 different routes: intra-peritoneal injection, immersion in a bacterial solution and cohabitation with infected fish. Mortality rates were significantly lower in infected rainbow trout that had received the feed additive: the overall mortality rate across all routes of infection was 18% in fish fed a diet containing the additive compared to 37% in fish that received unsupplemented feed. The route of infection also significantly impacted mortality, with average mortality rates of 60, 17.5 and 5% for intra-peritoneal injection, immersion and cohabitation, respectively. In general, fish were better protected against infection by immersion than infection by injection.

  20. Antimicrobial effect of the Biotronic® Top3 supplement and efficacy in protecting rainbow trout (Oncorhynchus mykiss) from infection by Aeromonas salmonicida subsp. salmonicida.

    PubMed

    Menanteau-Ledouble, Simon; Krauss, Ines; Goncalves, Rui Alexandre; Weber, Barbara; Santos, Gonçalo Abreu; El-Matbouli, Mansour

    2017-03-18

    Demand for more environmentally friendly practices have led to the adoption of several feed supplements by the fish farming industry. In the present study, we investigated a commercially available formula that includes a mixture of three compounds: organic acids, a phytochemical and Biomin® Permeabilizing Complex. This mixture demonstrated antimicrobial properties in vitro and was able to inhibit growth of multiple species of aquatic bacterial pathogens, including Aeromonas salmonicida. Bacterial challenge was performed using A. salmonicida and three exposure routes: intra-peritoneal injection, immersion, and cohabitation. Mortality rates following infection by injection were significantly decreased in the fish that had received the supplemented feed. Fish infected through the other routes did not show a significant difference in mortality. In term of farming performance, while the fish that had received the feed supplement showed an improvement in weight gain and final weight, these changes were not found to be statistically significant. Similarly, no significant difference was observed in the feed conversion ratio. The results of this study suggest that this feed supplement may be effective at protecting rainbow trout from fish furunculosis.

  1. Survival of two bacterial fish pathogens (Aeromonas salmonicida and the Enteric Redmouth Bacterium) in ozonated, chlorinated, and untreated waters

    USGS Publications Warehouse

    Wedemeyer, Gary A.; Nelson, Nancy C.

    1977-01-01

    Ozone and chlorine inactivation curves were determined in three water types at 20 °C for the destruction of the fish pathogens Aeromonas salmonicida, the etiologic agent of furunculosis, and the enteric redmouth bacterium (ERM). In phosphate-buffered distilled water, 0.01 mg/ℓ ozone inactivated 103 cells/ml of ERM and A. salmonicida in 1/2 and 10 min, respectively. Chlorine at this concentration had little effect on either pathogen and a residual of at least 0.05 mg/ℓ was needed to achieve a complete kill within a 10-min contact time. In soft lake water (30 mg/ℓ as CaCO3) a chlorine residual of 0.1 mg/ℓ rapidly  inactivated A. salmonicida and ERM but in hard water (120 mg/ℓ) A. salmonicida was more resistant and 0.2 mg/ℓ chlorine was required. Ozonation of the two lake waters at 90 mg O3∙h−1∙ℓ−1 (equivalent to a 0.01 mg/ℓ residual in ozone demand-free water) was required to destroy both pathogens within 10 min.In untreated soft lake water 103 cells/ml of A. salmonicida survived only 2 days, while the ERM bacterium (103 cells/ml) survived even after 20 day s in soft and hard untreated lake waters.

  2. Immunization of pacific salmon: comparison of intraperitoneal injection and hyperosmotic infiltration of Vibrio anguillarum and Aeromonas salmonicida bacterins

    USGS Publications Warehouse

    Antipa, Ross; Amend, Donald F.

    1977-01-01

    Two methods of immunizing fish, intraperitoneal (i.p.) injection and hyperosmotic infiltration, were compared for control of vibriosis and furunculosis in pen-reared coho salmon (Oncorhynchus kisutch) and chinook salmon (O. tshawytscha). Both methods provided significant protection against vibriosis under field test conditions. In coho salmon, hyperosmotic infiltration provided the best protection and fastest rise in antibody titer of seven treatments tested. In chinook salmon, hyperosmotic infiltration of Vibrio anguillarum and Aeromonas salmonicida vaccines resulted in 83.3% survival in comparison with 28.7% survival in controls. Both i.p. injection and hyperosmotic infiltration of V. anguillarum and A. salmonicida bacterins resulted in production of serum antibodies specific for each respective pathogen. Vaccination with bivalent V. anguillarum–A.salmonicida vaccines produced antibodies to both pathogens, and provided protection against vibriosis. Growth rates of vaccinated coho salmon were not significantly different from controls.

  3. Recovery of a fish pathogenic bacterium, Aeromonas salmonicida, from ebonyshell mussels Fusconaia ebena using nondestructive sample collection procedures

    USGS Publications Warehouse

    Starliper, C.E.

    2008-01-01

    Refugia are increasingly being used to maintain and propagate imperiled freshwater mussels for future population augmentations. Success for this endeavor is dependent on good husbandry, including a holistic program of resource health management. A significant aspect to optimal health is the prevention or control of infectious diseases. Describing and monitoring pathogens and diseases in mussels involves examination of tissues or samples collected from an appropriate number of individuals that satisfies a certain confidence level for expected prevalences of infections. In the present study, ebonyshell mussels Fusconaia ebena were infected with a fish pathogenic bacterium, Aeromonas salmonicida, through their cohabitation with diseased brook trout Salvelinus fontinalis. At a 100% prevalence of infection, the F. ebena were removed from the cohabitation tank to clean tanks that were supplied with pathogen-free water, which initiated their depuration of A. salmonicida. Three samples (nondestructive fluid, mantle, hemolymph) collected using nondestructive procedures were compared with fluids and soft tissue homogenates collected after sacrificing the mussels for recovery of the bacterium during this period of depuration. Nondestructive sample collections, especially ND fluid, provide a comparable alternative to sacrificing mussels to determine pathogen status.

  4. Screening microorganisms for insulin binding reveals binding by Burkholderia multivorans and Burkholderia cenocepacia and novel attachment of insulin to Aeromonas salmonicida via the A-layer.

    PubMed

    Nisr, Raid B; Moody, A John; Gilpin, Martyn L

    2012-03-01

    Exposure to microorganisms is considered an environmental factor that can contribute to Type 1 diabetes. Insulin-binding proteins (IBPs) on microorganisms may induce production of antibodies that can react with the human insulin receptor (HIR) with possible consequences in developing a diabetic autoimmune response against HIR and insulin. The interaction of insulin with microorganisms was studied by screening 45 microbial species for their ability to bind insulin. Binding assays were performed using labelled insulin to identify insulin-binding components on the microorganisms. Burkholderia multivorans and Burkholderia cenocepacia isolated from patients with cystic fibrosis (CF) and the fish pathogen Aeromonas salmonicida were the only strains of those tested, which showed insulin-binding components on their cell surfaces. Further work with A. salmonicida suggested that the insulin-binding activity of A. salmonicida is due to the A-layer. A mutant of A. salmonicida lacking the A-layer showed binding, but at a much reduced rate suggesting another insulin-binding component in addition to the high affinity of the A-protein. Soluble protein lysates were subjected to Western ligand blotting using peroxidase-labelled insulin to detect IBPs. Two positive IBPs were apparent at approximately 30 and 20 kDa in lysates from Burkholderia strains, but no IBP was detected in A. salmonicida lysates.

  5. Antimicrobial susceptibility testing of aquatic bacteria: quality control disk diffusion ranges for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 at 22 and 28 degrees C.

    PubMed

    Miller, R A; Walker, R D; Baya, A; Clemens, K; Coles, M; Hawke, J P; Henricson, B E; Hsu, H M; Mathers, J J; Oaks, J L; Papapetropoulou, M; Reimschuessel, R

    2003-09-01

    Quality control (QC) ranges for disk diffusion susceptibility testing of aquatic bacterial isolates were proposed as a result of a multilaboratory study conducted according to procedures established by the National Committee for Clinical Laboratory Standards (NCCLS). Ranges were proposed for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 at 22 and 28 degrees C for nine different antimicrobial agents (ampicillin, enrofloxacin, erythromycin, florfenicol, gentamicin, oxolinic acid, oxytetracycline, ormetoprim-sulfadimethoxine, and trimethoprim-sulfamethoxazole). All tests were conducted on standard Mueller-Hinton agar. With >/=95% of all data points fitting within the proposed QC ranges, the results from this study comply with NCCLS guidelines and have been accepted by the NCCLS Subcommittee for Veterinary Antimicrobial Susceptibility Testing. These QC guidelines will permit greater accuracy in interpreting results and, for the first time, the ability to reliably compare susceptibility test data between aquatic animal disease diagnostic laboratories.

  6. Antimicrobial Susceptibility Testing of Aquatic Bacteria: Quality Control Disk Diffusion Ranges for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 at 22 and 28°C

    PubMed Central

    Miller, R. A.; Walker, R. D.; Baya, A.; Clemens, K.; Coles, M.; Hawke, J. P.; Henricson, B. E.; Hsu, H. M.; Mathers, J. J.; Oaks, J. L.; Papapetropoulou, M.; Reimschuessel, R.

    2003-01-01

    Quality control (QC) ranges for disk diffusion susceptibility testing of aquatic bacterial isolates were proposed as a result of a multilaboratory study conducted according to procedures established by the National Committee for Clinical Laboratory Standards (NCCLS). Ranges were proposed for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 at 22 and 28°C for nine different antimicrobial agents (ampicillin, enrofloxacin, erythromycin, florfenicol, gentamicin, oxolinic acid, oxytetracycline, ormetoprim-sulfadimethoxine, and trimethoprim-sulfamethoxazole). All tests were conducted on standard Mueller-Hinton agar. With ≥95% of all data points fitting within the proposed QC ranges, the results from this study comply with NCCLS guidelines and have been accepted by the NCCLS Subcommittee for Veterinary Antimicrobial Susceptibility Testing. These QC guidelines will permit greater accuracy in interpreting results and, for the first time, the ability to reliably compare susceptibility test data between aquatic animal disease diagnostic laboratories. PMID:12958263

  7. The adjuvant effect of low frequency ultrasound when applied with an inactivated Aeromonas salmonicida vaccine to rainbow trout (Oncorhynchus mykiss).

    PubMed

    Cobo Labarca, Cristóbal; Makhutu, Mary; Lumsdon, Alexander E; Thompson, Kim D; Jung, Rainer; Kloas, Werner; Knopf, Klaus

    2015-03-10

    Vaccine adjuvants are classified according to their properties of either inducing the persistence of antigens within the animal after immunisation and/or activation of the animal's immune response. The adjuvant effect of low intensity low frequency sonophoresis (LFS) was tested in rainbow trout using an Aeromonas salmonicida bacterin vaccine administered by immersion vaccination using LFS at 37 kHz. The adjuvant effect obtained with LFS was compared with that of normal immersion or intraperitoneal injection vaccination. Quantitative PCR was used to measure bacterial DNA in vaccinated fish up to 35 days post-vaccination, while RT-qPCR was used to assess gene expression during the early and late immune response post-vaccination. Results showed that antigen uptake in the gills was significantly higher in the group exposed to low intensity LFS compared to the other two vaccination groups 15 min post-vaccination, but this initially high uptake did not persist over the rest of the experiment. In the kidney, by comparison, the vast majority of the samples analysed did not show the presence or persistence of the bacterin. Showing that the route of vaccine uptake using the A. salmonicida bacterin, does not influence the persistence of the bacterin in the gills or the kidney. On the other hand, LFS induced a higher inflammatory response and T-helper cell activation, characterized by a significant up-regulation of interleukin-8 (IL-8), IL-1ß and CD-4, respectively. The expression of Ig-M, Ig-T and Ig-D was up-regulated in gills (being significant for Ig-M), but not in the spleen and kidney of the sonicated group. Conversely, Ig-M was up-regulated in the spleen of the non-sonicated groups, but not in the sonicated group. This highlights the ability of ultrasound to enhance mucosal immunity. It remains to be established whether the up-regulation of Ig-M in gills would be sufficient to offer protection in fish infected with A. salmonicida.

  8. 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

  9. Integron-containing IncU R plasmids pRAS1 and pAr-32 from the fish pathogen Aeromonas salmonicida.

    PubMed

    Sørum, Henning; L'Abée-Lund, Trine M; Solberg, Asta; Wold, Anette

    2003-04-01

    A 45-kb R plasmid, pRAS1, that confers resistance to tetracyclines, trimethoprim, and sulfonamides was isolated in 1989 from an atypical strain of the fish pathogen Aeromonas salmonicida. This plasmid could be transferred by conjugation to Escherichia coli with a high degree of efficiency (frequency, 0.48). The following year pRAS1 was isolated from A. salmonicida subsp. salmonicida in the same area. Incompatibility group U plasmid pRAS1 contained a drug resistance-determining region of 12 kb consisting of a class 1 integron similar to In4 of Tn1696 but with a dfrA16 gene cassette inserted. Close to IS6100 at the right end of Tn4 was a truncated Tn1721. Restriction enzyme analysis showed that R plasmid pAr-32, isolated from A. salmonicida in Japan in 1970, had the same backbone structure as pRAS1, while the drug resistance-determining region contained a complex class 1 integron with an aadA2 cassette; the chloramphenicol resistance gene catA2, as in In6 of pSa; and a duplicate of the 3' conserved segment of the integron.

  10. Detection of Aeromonas salmonicida, causal agent of furunculosis in salmonid fish, from the tank effluent of hatchery-reared Atlantic salmon smolts.

    PubMed Central

    O'Brien, D; Mooney, J; Ryan, D; Powell, E; Hiney, M; Smith, P R; Powell, R

    1994-01-01

    The fish pathogen, Aeromonas salmonicida, could be detected only by bacteriological culture from the kidney of dead or moribund fish in one tank in a hatchery rearing Atlantic salmon (Salmo salar L.) smolts. However, by using a DNA probe specific for this species, allied to a PCR assay, the pathogen could be detected in water, feces and effluent samples taken from this fish tank. Also, the presence of the pathogen was found in effluent samples from two fish tanks containing apparently healthy fish. Subsequently, the presence of pathogen in these tanks was confirmed by an increase in the daily mortality rate and by a plate culture from moribund fish. Images PMID:7527205

  11. Enhanced Aeromonas salmonicida bacterin uptake and side effects caused by low frequency sonophoresis in rainbow trout (Oncorhynchus mykiss).

    PubMed

    Cobo, Cristóbal; Makosch, Katarzyna; Jung, Rainer; Kohlmann, Klaus; Knopf, Klaus

    2014-02-01

    Low frequency sonophoresis (LFS) has been recognized as one of the most advanced technologies in transdermal delivery of substances, due to the modification of the stratum corneum lipid bilayer, in focal skin applications in mammals. Based on these findings, LFS has been suggested as a potential technology to be used for enhancement in immersion fish vaccination. In contrast to mammals where LFS is applied to discrete regions of the skin, in fish the whole individual needs to be exposed for practical purposes. The current study evaluated the impact of LFS at 37 kHz on the uptake of an Aeromonas salmonicida bacterin and side effects of the treatment in rainbow trout. Quantitative real time PCR (qPCR) and immunohistochemistry were used to examine the bacterin uptake into skin and gill tissue. Side effects were assessed by behavioural examination, histology and blood serum analysis. The sonication intensity of 171 mW/cm² was enough for increasing skin permeability, but caused heavy erratic swimming and gill haemorrhages. Sonication intensities as low as 105 mW/cm² did not modify skin permeability and enhanced the bacterin uptake into the gill tissue by factor 15 compared to conventional immersion. Following sonication, the gill permeability for the bacterin decreased after 20 min and 120 min by factor 3 and 2, respectively. However, during sonication, erratic swimming of the fish raised some concerns. Further reduction of the sonication intensity to 57 mW/cm² did not induce erratic swimming, and the bacterin uptake into the gill tissue was still increased by factor 3. In addition, a decreasing albumin-globulin ratio in the serum of the rainbow trout within 40 min revealed that LFS leads to an inflammatory response. Consequently, based on both increased bacterin uptake and the inflammatory response, low intensity LFS has the potential to enhance vaccine immunity without significant side effects.

  12. Differences in detection of Aeromonas salmonicida in covertly infected salmonid fishes by the stress-inducible furunculosis test and culture-based assays

    USGS Publications Warehouse

    Cipriano, R.C.; Ford, L.A.; Smith, D.R.; Schachte, J.H.; Petrie, C.J.

    1997-01-01

    Accurate detection of Aeromonas salmonicida subsp. salmonicida (the cause of furunculosis disease) in covertly infected salmonids is difficult and is a cause of concern for those involved in fish health inspection and resource management programs. In this study, we examined populations of brook trout Salvelinus fontinalis, Atlantic salmon Salmo salar, and lake trout Salvelinus namaycush that previously sustained natural episodes of furunculosis. Consequently, the sampled fish were presumed to harbor latent infections. Mucus, gill, liver, kidney, heart, spleen, and intestine samples (N = 100 fish per group sampled) were processed and examined by (1) direct dilution counts and (2) quadrant streaking after a 48-h pre-enrichment in trypticase soy broth (TSB). Another subsample of fish from each group was then subjected to stress-inducible furunculosis tests. Stress tests detected A. salmonicida in three of four groups of fish that were examined whereas the pathogen was detected in only two of the groups analyzed with culture-based assays. Although pre-enrichment in TSB enhanced detection within internal sampling sites including the liver, heart, spleen, and kidney, enrichment did not enhance detection from mucus, gill, or intestinal samples.

  13. Rapid biochemical screening for Salmonella, Shigella, Yersinia, and Aeromonas isolates from stool specimens.

    PubMed

    De Ryck, R; Struelens, M J; Serruys, E

    1994-06-01

    Four screens for the rapid (4 to 6 h) biochemical detection of pathogens from enteric isolation media are described. The Salmonella screen consisted of Kligler iron agar (KIA), motility-indole-urea-tryptophan-deamination semisolid medium (MIU-TDA), and the o-nitrophenyl-beta-D-galactopyranoside (ONPG) test; the Shigella screen consisted of KIA, MIU-TDA, the ONPG test, and the lysine decarboxylation-indole test; the Yersinia screen consisted of a rhamnose broth; the Aeromonas screen consisted of a xylose agar plate. When tested on 2,102 fresh isolates and 71 stock strains, the screens correctly detected 212 enteric pathogens (sensitivity, 100%), with a specificity of 98.1%.

  14. Quorum sensing in Aeromonas hydrophila and Aeromonas salmonicida: identification of the LuxRI homologs AhyRI and AsaRI and their cognate N-acylhomoserine lactone signal molecules.

    PubMed Central

    Swift, S; Karlyshev, A V; Fish, L; Durant, E L; Winson, M K; Chhabra, S R; Williams, P; Macintyre, S; Stewart, G S

    1997-01-01

    Spent culture supernatants from both Aeromonas hydrophila and Aeromonas salmonicida activate a range of biosensors responsive to N-acylhomoserine lactones (AHLs). The genes for a quorum sensing signal generator and a response regulator were cloned from each Aeromonas species and termed ahyRI and asaRI, respectively. Protein sequence homology analysis places the gene products within the growing family of LuxRI homologs. ahyR and asaR are transcribed divergently from ahyI and asaI, respectively, and in both Aeromonas species, the genes downstream have been identified by DNA sequence and PCR analysis. Downstream of both ahyI and asaI is a gene with close homology to iciA, an inhibitor of chromosome replication in Escherichia coli, a finding which implies that in Aeromonas, cell division may be linked to quorum sensing. The major signal molecule synthesized via both AhyI and AsaI was purified from spent culture supernatants and identified as N-(butanoyl)-L-homoserine lactone (BHL) by thin-layer chromatography, high-pressure liquid chromatography analysis, and mass spectrometry. In addition, a second, minor AHL, N-hexanoyl-L-homoserine lactone, was identified. Transcriptional reporter studies with ahyI::luxCDABE fusions indicate that AhyR and BHL are both required for ahyI transcription. For A. salmonicida, although the addition of exogenous BHL gives only a small stimulation of the production of serine protease with comparison to the control culture, the incorporation of a longer-chain AHL, N-(3-oxodecanoyl)-L-homoserine lactone, reduced the final level (by approximately 50%) and delayed the appearance (from an A650 of 0.9 in the control to an A650 of 1.2 in the test) of protease in the culture supernatant. These data add A. hydrophila and A. salmonicida to the growing family of gram-negative bacteria now known to control gene expression through quorum sensing. PMID:9286976

  15. Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peracetic acid (PAA) is an agent used for disinfection in aquaculture. PAA contributes to sustainable aquaculture, because it releases no harmful residue in the environment. However, there is lack of guideline about the effective application of different PAA products against various pathogens in p...

  16. Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peracetic acid is a therapeutic agent used for disinfection in aquaculture, but it must be investigated thoroughly in order to mitigate diseases without harmful effects to fish. These agents should not leave dangerous residues in the environment in order to successfully contribute to sustainable aq...

  17. Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peracetic acid is a therapeutic agent used for disinfection, but it must be investigated in order to mitigate diseases without harmful effects to the fish. These agents should not leave dangerous residues in the environment in order to successfully contribute to sustainable aquaculture. The aim of ...

  18. Effect of dietary β-glucan on growth, survival and regulation of immune processes in rainbow trout (Oncorhynchus mykiss) infected by Aeromonas salmonicida.

    PubMed

    Ji, Liqin; Sun, Guoxiang; Li, Jun; Wang, Yi; Du, Yishuai; Li, Xian; Liu, Ying

    2017-03-07

    The present study evaluated the effects of dietary β-glucan (0, 0.05%, 0.1%, and 0.2%) on growth performance after 42 days of feeding. Thereafter, rainbow trout (Oncorhynchus mykiss) were infected with Aeromonas salmonicida, and survival rates as well as the regulating processes of stress- and immune-related factors were analyzed. In general, higher dietary β-glucan levels obviously improved specific growth rate (SGR), weight gain (WG) and feed efficiency (FE) (P ≤ 0.05). Survival rates in β-glucan groups increased significantly compared with the control group after A. salmonicida infection (P ≤ 0.05). Serum total superoxide dimutase (T-SOD), peroxidase (POD) as well as catalase (CAT) activities, and their mRNA expressions in the head kidney of fish in the β-glucan groups generally increased to higher levels after infection, and more quickly, compared with in the control group. Serum lysozyme (LSZ) and its expression in the head kidney in β-glucan groups reached a higher peak earlier than in the control group. Serum glutamic oxalacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) levels in the β-glucan groups were significantly lower than in the control group (P ≤ 0.05). The peak of heat shock protein 70 (HSP70) expression in the 0.2% β-glucan group was higher and occurred earlier than in other groups (P ≤ 0.05). These results confirm that 0.1% and 0.2% dietary β-glucan are beneficial for promoting growth in rainbow trout and enhancing resistance against A. salmonicida. Furthermore, β-glucan could play an important role in regulating stress- and immune-related factors in rainbow trout to more quickly fight against bacterial infection.

  19. Efficacy of an extract from garlic, Allium sativum, against infection with the furunculosis bacterium, Aeromonas salmonicida, in rainbow trout, Oncorhynchus mykiss

    USGS Publications Warehouse

    Breyer, Kate E.; Getchell, Rodman G.; Cornwell, Emily R.; Wooster, Gregory A.; Ketola, H. George; Bowser, Paul R.

    2015-01-01

    Juvenile rainbow trout, Oncorhynchus mykiss, were fed diets containing 0, 0.5, 1.0, and 2.0% of a garlic extract, challenged with a modified 50% lethal dose of Aeromonas salmonicida and monitored for 28 d. There were significant increases in survival of trout fed 0.5 and 1.0% garlic extract as compared to the control and 2.0% garlic extract groups. A target animal safety study was performed at varying increments using the target dose of 0.5% garlic extract at 0× (0% garlic extract), 1× (0.5% garlic extract), 3× (1.5% garlic extract), and 5× (2.5% garlic extract) for 3× (6 wk) the duration of the original study. There was a significant increase in the level of circulating lymphocytes and a significant decrease in the level of circulating monocytes. The latter correlated to an increased level of pigment-containing macrophage centers within the renal tissue as garlic extract dosing increased, denoting a potential deleterious inflammatory effect as macrophage infiltration became severe at the highest dose. These studies suggest that feeding low-dose (0.5% or 1.0%) garlic extract improves survivability in rainbow trout when challenged with A. salmonicida and appears safe; however, higher levels do not appear to be effective and may cause deleterious effects on health.

  20. Characterization of susceptibility and carrier status of burbot, Lota lota (L.), to IHNV, IPNV, Flavobacterium psychrophilum, Aeromonas salmonicida and Renibacterium salmoninarum.

    PubMed

    Polinski, M P; Fehringer, T R; Johnson, K A; Snekvik, K R; Lapatra, S E; Lafrentz, B R; Ireland, S C; Cain, K D

    2010-07-01

    In this study, susceptibility and potential carrier status of burbot, Lota lota, were assessed for five important fish pathogens. Burbot demonstrated susceptibility and elevated mortality following challenge with infectious haematopoietic necrosis virus (IHNV) by immersion and to Aeromonas salmonicida by intraperitoneal (i.p.) injection. IHNV persisted in fish for at least 28 days, whereas A. salmonicida was not re-isolated beyond 17 days post-challenge. In contrast, burbot appeared refractory to Flavobacterium psychrophilum following intramuscular (i.m.) injection and to infectious pancreatic necrosis virus (IPNV) by immersion. However, i.p injection of IPNV resulted in re-isolation of virus from fish for the duration of the 28 day challenge. Renibacterium salmoninarum appeared to induce an asymptomatic carrier state in burbot following i.p. injection, but overt manifestation of disease was not apparent. Viable bacteria persisted in fish for at least 41 days, and bacterial DNA isolated by diagnostic polymerase chain reaction was detected from burbot kidney tissue 90 days after initial exposure. This study is the first to investigate susceptibility of burbot to selected fish pathogens, and this information will aid in efforts to culture and manage this species.

  1. Use of human cDNA microarrays for identification of differentially expressed genes in Atlantic salmon liver during Aeromonas salmonicida infection.

    PubMed

    Tsoi, Stephen C M; Cale, Jacqueline M; Bird, Ian M; Ewart, Vanya; Brown, Laura L; Douglas, Susan

    2003-01-01

    Commercially available human complementary DNA microarrays were used to compare differential expression in the livers of Atlantic salmon ( Salmo salar) infected with Aeromonas salmonicida and of healthy fish. Complementary DNA probes were prepared from total RNA isolated from livers of control salmon and infected salmon by reverse transcription in the presence of (33)P-dCTP and independently hybridized to human GENE-FILTERS GF211 microarrays. Of the 4131 known genes on the microarray, 241 spots gave clearly detectable signals using labeled RNA from the control salmon liver. Of these, 4 spots were consistently found to have a greater than 2-fold increase in infected salmon compared with controls when using the same pair of filters to generate hybridization data from triplicates. These up-regulated genes were ADP/ATP translocase (AAT2), Na(+)/K(+) ATPase, acyloxyacyl hydrolase (AOAH), and platelet-derived growth factor (PDFG-A). A BlastN search revealed an AAT2 homolog from Atlantic salmon, and a reverse transcriptase polymerase chain reaction assay using primers based on this sequence confirmed its up-regulation (approx. 1.8-fold) during early infection. This work demonstrates the feasibility of using human microarrays to facilitate the discovery of differentially expressed genes in Atlantic salmon, for which no homologous microarrays are available.

  2. Lipopolysaccharides isolated from Aeromonas salmonicida and Vibrio anguillarum show quantitative but not qualitative differences in inflammatory outcome in Sparus aurata (Gilthead seabream).

    PubMed

    Boltaña, S; Tridico, R; Teles, M; Mackenzie, S; Tort, L

    2014-08-01

    In fish, the defence system recognises pathogenic microorganisms via pathogen recognition receptors (PRRs) that sense particular structures of the pathogens; the so-called pathogen associated molecular patterns (PAMPs) such as bacterial lipopolysaccharides (LPSs). The result of the PAMP-PRR interactions leads to complex and orchestrated immune responses. In this study, Sparus aurata (Gilthead seabream) were intraperitoneally injected with purified lipopolysaccharide (LPS) from Aeromonas salmonicida (As)- and Vibrio anguillarum (Va) (1 mg*Kgfish(-1)), both Gram negative bacteria responsible for vibriosis and furunculosis respectively, therefore causing an impact upon marine fish cultures. Head-kidney, intestine, spleen, liver and blood samples were collected at 3, 6, 12 and 24 h post-injection. Plasma levels of cortisol, prostaglandins and lactate were measured and were significantly increased after As-LPS and Va-LPS treatment. Furthermore, tissue-specific differences of the gene regulatory patterns were evident for each LPS. When monocyte/macrophage cell cultures were challenged with As-LPS and Va-LPS, the pro-inflammatory cytokine mRNA abundances present a similar pattern of response. However, As-LPS always triggered a stronger response concerning TNFα, IL1β and cyclooxygenase-2 (COX2) mRNA abundance as well as PGE2 levels in the supernatant. Overall, the results indicate that specific LPSs do not activate different pro-inflammatory responses and that the observed gene expression pattern is tissue and concentration dependent.

  3. Steelhead trout Oncorhynchus mykiss metabolic rate is affected by dietary Aloe vera inclusion but not by mounting an immune response against formalin-killed Aeromonas salmonicida.

    PubMed

    Zanuzzo, F S; Urbinati, E C; Nash, G W; Gamperl, A K

    2015-07-01

    The oxygen consumption (MO2) of two groups of 10° C acclimated steelhead trout Oncorhynchus mykiss was measured for 72 h after they were given a 100 µl kg(-1) intraperitoneal injection of formalin-killed Aeromonas salmonicida (ASAL) or phosphate-buffered saline (PBS). In addition, plasma cortisol levels were measured in fish from both groups prior to, and 1 and 3 h after, they were given a 30 s net stress. The first group was fed an unaltered commercial diet for 4 weeks, whereas the second group was fed the same diet but with 0·5% (5 g kg(-1) ) Aloe vera powder added; A. vera has potential as an immunostimulant for use in aquaculture, but its effects on basal and acute phase response (APR)-related metabolic expenditures and stress physiology, are unknown. Injection of ASAL v. PBS had no measurable effect on the MO2 of O. mykiss indicating that the APR in this species is not associated with any net increase in energy expenditure. In contrast, incorporating 0·5% A. vera powder into the feed decreased routine metabolic rate by c. 8% in both injection groups and standard metabolic rate in the ASAL-injected group (by c. 4 mg O2 kg(-1) h(-1) ; 5%). Aloe vera fed fish had resting cortisol levels that were approximately half of those in fish on the commercial diet (c. 2·5 v. 5·0 ng ml(-1) ), but neither this difference nor those post-stress reached statistical significance (P > 0·05).

  4. Distribution and retention of antigens of Aeromonas salmonicida in Atlantic salmon (Salmo salar L.) vaccinated with a DeltaaroA mutant or formalin-inactivated bacteria in oil-adjuvant.

    PubMed

    Grove, S; Høie, S; Evensen, Ø

    2003-10-01

    In this study we report the differences in distribution and retention of Aeromonas salmonicida antigens after vaccination with two different vaccines. Parr of Atlantic salmon (Salmo salar) were given intraperitoneal injections of either a commercial, monovalent furunculosis vaccine (Apoject) or live, attenuated A. salmonicida (DeltaaroA). Fish were sampled at weeks 2, 4 and 12 post-vaccination and head kidney and spleen were collected. Presence of LPS and 16S rDNA in isolated leukocytes were investigated by immunocytochemistry and polymerase chain reaction (PCR).16S rDNA was detected in head kidney and spleen of all DeltaaroA vaccinated and most Apoject-vaccinated fish at weeks 2 and 4. At week 12, 16S rDNA was detected in none of the DeltaaroA vaccinated fish, but it was detected in head kidney of 75% of Apoject-vaccinated fish. LPS was detected in both vaccination groups at all sampling times, but most frequently in the DeltaaroA vaccinated fish (in head kidney 75-83% vs. 50%, in spleen 58-67% vs. 17-25%).

  5. Inhibitory activity of monoacylglycerols on biofilm formation in Aeromonas hydrophila, Streptococcus mutans, Xanthomonas oryzae, and Yersinia enterocolitica.

    PubMed

    Ham, Youngseok; Kim, Tae-Jong

    2016-01-01

    Biofilm provides a bacterial hiding place by forming a physical barrier and causing physiological changes in cells. The elimination of biofilm is the main goal of hygiene. Chemicals that are inhibitory to biofilm formation have been developed for use in food, personal hygiene products, and medical instruments. Monoacylglycerols are recognized as safe and are used in food as emulsifiers. In this study, the inhibitory activity of monoacylglycerols on bacterial biofilm formation was evaluated systematically with four bacterial strains, Aeromonas hydrophila, Streptococcus mutans, Xanthomonas oryzae, and Yersinia enterocolitica. Monoacylglycerols with two specific lengths of fatty acid moiety, monolaurin and monobehenin, were found to have strong inhibitory activity toward bacterial biofilm formation of S. mutans, X. oryzae, and Y. enterocolitica in a strain specific manner. First, this result suggested that biofilm formation was not inhibited by the detergent characteristics of monoacylglycerols. This suggestion was supported by the inhibitory action of monolaurin on biofilm development but not on the initial cell attachment of Y. enterocolitica in flow cytometric observation. Second, it was also suggested that two distinct response mechanisms to monoacylglycerols existed in bacteria. The existence of these two inhibitory response mechanisms was bacterial strain specific.

  6. Bactericidal activity of juvenile chinook salmon macrophages against Aeromonas salmonicida after exposure to live or heat-killed Renibacterium salmoninarum or to soluble proteins produced by R. salmoninarum

    USGS Publications Warehouse

    Siegel, D.C.; Congleton, J.L.

    1997-01-01

    Macrophages isolated from the anterior kidney of juvenile chinook salmon Oncorhynchus tshawytscha in 96-well microtiter plates were exposed for 72 h to 0, 105, or 106 live or heat-killed Renibacterium salmoninarum cells per well or to 0, 0.1, 1.0, or 10 ??g/mL of R. salmoninarum soluble proteins. After treatment, the bactericidal activity of the macrophages against Aerornonas salmonicida was determined by a colorimetric assay based on the reduction of the tetrazolium dye MTT to formazan by viable bacteria. The MTT assay was modified to allow estimation of the percentage of bacteria killed by reference to a standard curve relating the number of bacteria added to microtiter wells to absorbance by formazan at 600 nm. The live and heat-killed R. salmoninarum treatments significantly (P < 0.001) increased killing of A. salmonicida by chinook salmon macrophages. In each of the five trials, significantly (P < 0.05) greater increases in killing occurred after exposure to 105 R. salmoninarum cells than to 106 R. salmoninarum cells per well. In contrast, treatment of macrophages with 10 ??g/mL R. salmoninarum soluble proteins significantly (P < 0.001) decreased killing of A. salmonicida, but treatment with lower doses did not. These results show that the bactericidal activity of chinook salmon macrophages is stimulated by exposure to R. salmoninarum cells at lower dose levels but inhibited by exposure to R. salmoninarum cells or soluble proteins at higher dose levels.

  7. In vitro antibacterial activities of ethanol extract of iranian propolis (EEIP) against fish pathogenic bacteria (Aeromonas hydrophila, Yersinia ruckeri & Streptococcus iniae).

    PubMed

    Tukmechi, Amir; Ownagh, Abdolghaffar; Mohebbat, Ali

    2010-10-01

    The "in vitro" antibacterial activity of ethanol extract of propolis (EEIP) from Urmia, Iran was investigated against three prevalent species of fish bacterial pathogens including: Aeromonas hydrophila LMG 3770, Yersinia ruckeri LMG 3279 and Streptococcus iniae LMG 14520. In this study two standard susceptibility testing techniques (Micro-broth dilution method and Agar-well diffusion method) were used to evaluation of the antibacterial activity of EEIP against the mentioned micro-organisms. Also the chemical composition of propolis was determined by the method of Gas chromatography-mass spectrometry (GC-MS). Twenty-six compounds were identified by gas chromatography-mass spectrometry analysis. Results showed Chemical composition of EEIP contained significant amounts of flavonoids, Sesquiterpenes - mainly Eudesmol and Caryophyllene oxide - aromatic acid, and low amounts of aldehydes and triterpens. Furthermore the ethanol extract of propolis inhibited the growth of all examined micro-organisms with the highest antimicrobial activity against Gram-positive bacteria Streptococcus iniae. Ethanol did not influence the antimicrobial effect of EEIP. These antibacterial properties would warrant further studies on the clinical applications of propolis in aquaculture field.

  8. Histopathological findings in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with 3 different Aeromonas species.

    PubMed

    Zepeda-Velázquez, Andrea Paloma; Vega-Sánchez, Vicente; Salgado-Miranda, Celene; Soriano-Vargas, Edgardo

    2015-07-01

    This study describes the macroscopic and microscopic lesions in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with genetically identified Aeromonas salmonicida, A. hydrophila, and A. veronii species. The genus Aeromonas includes bacteria that naturally inhabit both waterways and organisms. At least 27 Aeromonas species have been identified to date, some of which can cause significant economic losses in aquaculture. As up to 68.8% of Aeromonas isolates may be misidentified in routine biochemical and phenotypic tests, however, reported cases of Aeromonas infection in fish may be wrongly identified. Our findings confirmed that the 3 Aeromonas species studied are associated with septicemia and dermal lesions in rainbow trout.

  9. Histopathological findings in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with 3 different Aeromonas species

    PubMed Central

    Zepeda-Velázquez, Andrea Paloma; Vega-Sánchez, Vicente; Salgado-Miranda, Celene; Soriano-Vargas, Edgardo

    2015-01-01

    This study describes the macroscopic and microscopic lesions in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with genetically identified Aeromonas salmonicida, A. hydrophila, and A. veronii species. The genus Aeromonas includes bacteria that naturally inhabit both waterways and organisms. At least 27 Aeromonas species have been identified to date, some of which can cause significant economic losses in aquaculture. As up to 68.8% of Aeromonas isolates may be misidentified in routine biochemical and phenotypic tests, however, reported cases of Aeromonas infection in fish may be wrongly identified. Our findings confirmed that the 3 Aeromonas species studied are associated with septicemia and dermal lesions in rainbow trout. PMID:26130859

  10. Aeromonas phages encode tRNAs for their overused codons.

    PubMed

    Prabhakaran, Ramanandan; Chithambaram, Shivapriya; Xia, Xuhua

    2014-01-01

    The GC-rich bacterial species, Aeromonas salmonicida, is parasitised by both GC-rich phages (Aeromonas phages - phiAS7 and vB_AsaM-56) and GC-poor phages (Aeromonas phages - 25, 31, 44RR2.8t, 65, Aes508, phiAS4 and phiAS5). Both the GC-rich Aeromonas phage phiAS7 and Aeromonas phage vB_AsaM-56 have nearly identical codon usage bias as their host. While all the remaining seven GC-poor Aeromonas phages differ dramatically in codon usage from their GC-rich host. Here, we investigated whether tRNA encoded in the genome of Aeromonas phages facilitate the translation of phage proteins. We found that tRNAs encoded in the phage genome correspond to synonymous codons overused in the phage genes but not in the host genes.

  11. Yersinia enterocolitica organism (image)

    MedlinePlus

    This picture shows the organism Yersinia enterocolitica . Yersinia organisms cause a wide range of disease but are most often associated with diarrhea or gastrointestinal symptoms. Yersinia infection is ...

  12. 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.

  13. Pathogenicity of Mexican isolates of Aeromonas sp. in immersion experimentally-infected rainbow trout (Oncorhynchus mykiss, Walbaum 1792).

    PubMed

    Zepeda-Velázquez, Andrea Paloma; Vega-Sánchez, Vicente; Ortega-Santana, César; Rubio-Godoy, Miguel; de Oca-Mira, Dany Montes; Soriano-Vargas, Edgardo

    2017-05-01

    Ten species of Aeromonas have been previously identified in farmed rainbow trout from Mexico. The aim of the current study was to investigate the pathogenicity of 10 Aeromonas isolates belonging to 10 different Aeromonas species in immersion experimentally-infected rainbow trout fry. Isolates of A. bestiarum, A. hydrophila, A. salmonicida, and A. veronii produced significant mortality (8.8%, 12.2%, 18.8%, and 8.8%, respectively). Isolates of A. caviae and A. sobria produced no significantly mortality (3.3% and 1.1%, respectively). No mortality was recorded in fish infected with A. allosaccharophila, A. lusitana, A. media, or A. popoffii. Microscopic lesions and bacterial reisolation were registered in liver of fish infected with the ten different Aeromonas isolates. Our results suggest that all Aeromonas species included in the study have the ability to colonize the liver. The results have confirmed that species A. bestiarum, A. hydrophila, A. salmonicida, and A. veronii affected fish as elsewhere reported. In conclusion, the variation in pathogenicity of Aeromonas isolates included in the study, emphasizes the importance of active, on-going monitoring of Aeromonas in the Mexican rainbow trout farming.

  14. 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...

  15. 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).

  16. Yersinia enterocolitica

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The detection of plasmid-bearing (pYV) human pathogenic strains of Yersinia enterocolitica depends on the expression of various pYV-associated virulence characteristics. However, diagnostic techniques based on pYV encoded phenotypes have limited reliability due to the unstable nature of pYV. Two r...

  17. Hydrogenosomes in the diplomonad Spironucleus salmonicida

    PubMed Central

    Jerlström-Hultqvist, Jon; Einarsson, Elin; Xu, Feifei; Hjort, Karin; Ek, Bo; Steinhauf, Daniel; Hultenby, Kjell; Bergquist, Jonas; Andersson, Jan O.; Svärd, Staffan G.

    2013-01-01

    Acquisition of the mitochondrion is a key event in the evolution of the eukaryotic cell, but diversification of the organelle has occurred during eukaryotic evolution. One example of such mitochondria-related organelles (MROs) are hydrogenosomes, which produce ATP by substrate-level phosphorylation with hydrogen as a byproduct. The diplomonad parasite Giardia intestinalis harbours mitosomes, another type of MRO. Here we identify MROs in the salmon parasite Spironucleus salmonicida with similar protein import and Fe–S cluster assembly machineries as in Giardia mitosomes. We find that hydrogen production is prevalent in the diplomonad genus Spironucleus, and that S. salmonicida MROs contain enzymes characteristic of hydrogenosomes. Evolutionary analyses of known hydrogenosomal components indicate their presence in the diplomonad ancestor, and subsequent loss in Giardia. Our results suggest that hydrogenosomes are metabolic adaptations predating the split between parabasalids and diplomonads, which is deeper than the split between animals and fungi in the eukaryotic tree. PMID:24042146

  18. 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.

  19. An investigation of the bactericidal activity of selected essential oils to Aeromonas spp.

    USGS Publications Warehouse

    Starliper, Clifford E.; Ketolab, Henry G.; Noyes, Andrew D.; Schill, William B.; Henson, Fred G.; Chalupnicki, Marc A.; Dittman, Dawn E.

    2015-01-01

    Diseases of fishes caused by Aeromonas spp. are common, have broad host ranges and may cause high mortality. Treatments for captive-reared populations using antimicrobials are limited with concerns for bacterial resistance development and environmental dissemination. This study was done to determine if selected plant-derived essential oils were bactericidal to Aeromonas spp. Initially, twelve essential oils were evaluated using a disk diffusion assay to an isolate of A. salmonicida subsp. salmonicida, cause of fish furunculosis. The greatest zones of inhibition were obtained with oils of cinnamon Cinnamomum cassia, oregano Origanum vulgare, lemongrass Cymbopogon citratus and thyme Thymus vulgaris. Minimum bactericidal concentrations (MBC’s) were determined for these four oils, Allimed® (garlic extract, Allium sativum) and colloidal silver to sixty-nine isolates representing nine Aeromonas spp. The lowest mean MBC’s (0.02 to 0.04%) were obtained with three different sources of cinnamon oil. MBC’s for three sources of oregano and lemongrass oils ranged from 0.14 to 0.30% and 0.10 to 0.65%, respectively, and for two thyme oils were 2.11 and 2.22%. The highest concentration (5%) of Allimed® tested resulted in MBC’s to twelve isolates. A concentration of silver greater than 15 mg/L would be required to determine MBC’s for all but one isolate

  20. An investigation of the bactericidal activity of selected essential oils to Aeromonas spp.

    USGS Publications Warehouse

    Starliper, Clifford E.; Ketola, H. George; Noyes, Andrew D.; Schill, William B.; Henson, Fred G.; Chalupnicki, Marc; Dittman, Dawn E.

    2015-01-01

    Diseases of fishes caused by Aeromonas spp. are common, have broad host ranges and may cause high mortality. Treatments of captive-reared populations using antimicrobials are limited with concerns for bacterial resistance development and environmental dissemination. This study was done to determine whether selected plant-derived essential oils were bactericidal to Aeromonas spp. Initially, twelve essential oils were evaluated using a disk diffusion assay to an isolate of A. salmonicida subsp. salmonicida, cause of fish furunculosis. The greatest zones of inhibition were obtained with oils of cinnamon Cinnamomum cassia, oregano Origanum vulgare, lemongrass Cymbopogon citratus and thyme Thymus vulgaris. Minimum bactericidal concentrations (MBC’s) were determined for these four oils, Allimed® (garlic extract, Allium sativum) and colloidal silver to sixty-nine isolates representing nine Aeromonas spp. The lowest mean MBCs (0.02–0.04%) were obtained with three different sources of cinnamon oil. MBCs for three sources of oregano and lemongrass oils ranged from 0.14% to 0.30% and 0.10% to 0.65%, respectively, and for two thyme oils were 2.11% and 2.22%. The highest concentration (5%) of Allimed® tested resulted in MBCs to twelve isolates. A concentration of silver greater than 15 mg/L would be required to determine MBCs for all but one isolate.

  1. An investigation of the bactericidal activity of selected essential oils to Aeromonas spp.

    PubMed

    Starliper, Clifford E; Ketola, Henry G; Noyes, Andrew D; Schill, William B; Henson, Fred G; Chalupnicki, Marc A; Dittman, Dawn E

    2015-01-01

    Diseases of fishes caused by Aeromonas spp. are common, have broad host ranges and may cause high mortality. Treatments of captive-reared populations using antimicrobials are limited with concerns for bacterial resistance development and environmental dissemination. This study was done to determine whether selected plant-derived essential oils were bactericidal to Aeromonas spp. Initially, twelve essential oils were evaluated using a disk diffusion assay to an isolate of A. salmonicida subsp. salmonicida, cause of fish furunculosis. The greatest zones of inhibition were obtained with oils of cinnamon Cinnamomum cassia, oregano Origanum vulgare, lemongrass Cymbopogon citratus and thyme Thymus vulgaris. Minimum bactericidal concentrations (MBC's) were determined for these four oils, Allimed® (garlic extract, Allium sativum) and colloidal silver to sixty-nine isolates representing nine Aeromonas spp. The lowest mean MBCs (0.02-0.04%) were obtained with three different sources of cinnamon oil. MBCs for three sources of oregano and lemongrass oils ranged from 0.14% to 0.30% and 0.10% to 0.65%, respectively, and for two thyme oils were 2.11% and 2.22%. The highest concentration (5%) of Allimed® tested resulted in MBCs to twelve isolates. A concentration of silver greater than 15 mg/L would be required to determine MBCs for all but one isolate.

  2. An investigation of the bactericidal activity of selected essential oils to Aeromonas spp.

    PubMed Central

    Starliper, Clifford E.; Ketola, Henry G.; Noyes, Andrew D.; Schill, William B.; Henson, Fred G.; Chalupnicki, Marc A.; Dittman, Dawn E.

    2014-01-01

    Diseases of fishes caused by Aeromonas spp. are common, have broad host ranges and may cause high mortality. Treatments of captive-reared populations using antimicrobials are limited with concerns for bacterial resistance development and environmental dissemination. This study was done to determine whether selected plant-derived essential oils were bactericidal to Aeromonas spp. Initially, twelve essential oils were evaluated using a disk diffusion assay to an isolate of A. salmonicida subsp. salmonicida, cause of fish furunculosis. The greatest zones of inhibition were obtained with oils of cinnamon Cinnamomum cassia, oregano Origanum vulgare, lemongrass Cymbopogon citratus and thyme Thymus vulgaris. Minimum bactericidal concentrations (MBC’s) were determined for these four oils, Allimed® (garlic extract, Allium sativum) and colloidal silver to sixty-nine isolates representing nine Aeromonas spp. The lowest mean MBCs (0.02–0.04%) were obtained with three different sources of cinnamon oil. MBCs for three sources of oregano and lemongrass oils ranged from 0.14% to 0.30% and 0.10% to 0.65%, respectively, and for two thyme oils were 2.11% and 2.22%. The highest concentration (5%) of Allimed® tested resulted in MBCs to twelve isolates. A concentration of silver greater than 15 mg/L would be required to determine MBCs for all but one isolate. PMID:25685547

  3. 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.

  4. Rare Infections: Yersinia Enterocolitica and Yersinia Pseudotuberculosis

    MedlinePlus

    ... Pediatrician Health Issues Conditions Abdominal ADHD Allergies & Asthma Autism Cancer Chest & Lungs Chronic Conditions Cleft & Craniofacial Developmental ... Yersinia infections. Last Updated 11/21/2015 Source Immunizations & Infectious Diseases: An Informed Parent's Guide (Copyright © 2006 ...

  5. 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.

  6. 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

  7. 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...

  8. Aeromonas Diversity and Antimicrobial Susceptibility in Freshwater—An Attempt to Set Generic Epidemiological Cut-Off Values

    PubMed Central

    Baron, Sandrine; Granier, Sophie A.; Larvor, Emeline; Jouy, Eric; Cineux, Maelan; Wilhelm, Amandine; Gassilloud, Benoit; Le Bouquin, Sophie; Kempf, Isabelle; Chauvin, Claire

    2017-01-01

    The importance of the role of environment in the dissemination of antimicrobial resistant bacteria is now well recognized. Thus, bacterial indicators to monitor the phenomena are required. The Aeromonas genus is autochthonous in the aquatic environment and easy to detect in any water type, such as freshwater, or wastewater. These microorganisms are also causing infections in humans and animals (including fish). Furthermore, as Aeromonas spp. is able to acquire antimicrobial resistance mechanisms, it is candidate for indicator bacteria to follow antimicrobial resistance dissemination in aquatic environments. Unfortunately, to date, interpretation criteria for Aeromonas spp. for antimicrobial susceptibility tests are scarce in the literature. No epidemiological cut-off values for Aeromonas are currently available at EUCAST to interpret Minimum Inhibitory Concentrations (MIC). The only interpretation criteria available are clinical breakpoints from CLSI that are adapted from Enterobacteriaceae. Based on the results of MIC distributions obtained for a collection of environmental isolates of Aeromonas, this study aimed at proposing tentative epidemiological cut-off values (COWT) for Aeromonas spp. assessing whether the genus is an acceptable level of definition. Thus, 233 isolates collected from 16 rivers were identified at species level using Maldi-Tof (Bruker). Eleven different species were identified, the most abundant were A. bestiarum (n = 54), A. salmonicida (n = 45), A. sobria (n = 41), and A. eucrenophila (n = 37). 96-well micro-plates containing different concentrations of 15 antimicrobials, namely cefotaxime, ceftazidime, chloramphenicol, colistin, enrofloxacin, erythromycin, florfenicol, flumequine, gentamicin, nalidixic acid, oxolinic acid, streptomycin, temocillin, tetracycline, and trimethoprim-sulfamethoxazole, were prepared. The broth micro-dilution method was used to determine the antimicrobial susceptibility of each isolate. The estimation of COWT

  9. RFLP-PCR analysis of the aroA gene as a taxonomic tool for the genus Aeromonas.

    PubMed

    Cascón Soriano, A; Anguita Castillo, J; Hernanz Moral, C; Sánchez Salazar, M; Yugueros Marcos, J; Naharro Carrasco, G

    1997-11-15

    The aroA gene has been identified as a target in screening for the presence of most Aeromonas species so far described by PCR. Synthetic oligonucleotide primers of 24 and 25 nucleotides were used by PCR assay to amplify a sequence of the aroA gene, which encodes 3-phosphoshikimate-1-carboxyvinyltransferase, a key enzyme of aromatic amino acids and folate biosynthetic pathway. A 1236-bp DNA fragment, representing most of the aroA gene, according to the nucleotide sequence of A. salmonicida, was amplified from all Aeromonas species tested, which represented most of the 14 hybridization groups. HaeII digestion of the 1236-bp fragment generated a restriction fragment length polymorphisms which could be used as a powerful tool for identification of aeromonads to the genus level.

  10. Yersinia nurmii sp. nov.

    PubMed

    Murros-Kontiainen, Anna; Fredriksson-Ahomaa, Maria; Korkeala, Hannu; Johansson, Per; Rahkila, Riitta; Björkroth, Johanna

    2011-10-01

    This study was set up to identify three Gram-negative, rod-shaped strains originating from broiler meat packaged under a modified atmosphere. A polyphasic taxonomic approach, including multilocus sequence analysis (MLSA) of five genes (16S rRNA, glnA, gyrB, recA and HSP60), DNA-DNA reassociation between the closest phylogenetic neighbours and determination of relevant phenotypic properties, was applied. Phylogenetic analysis of the 16S rRNA gene sequences grouped these strains together and within the genus Yersinia. MLSA of the 16S rRNA gene and four housekeeping genes showed that the strains formed a monophyletic group separate from other Yersinia species in all phylogenetic trees constructed. The strains had a phenotypic profile different from those of other representatives of the genus Yersinia, but most similar to that of Yersinia ruckeri. Typical virulence markers for pathogenic Yersinia were not detected. Based on phylogenetic, phenotypic and DNA-DNA reassociation data, a novel species, Yersinia nurmii sp. nov., is proposed for the isolated strains. The type strain is APN3a-c(T) ( = DSM 22296(T)  = LMG 25213(T)).

  11. Dynamics of Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae in a sewage treatment pond.

    PubMed Central

    Monfort, P; Baleux, B

    1990-01-01

    The spatiotemporal dynamics of Aeromonas spp. and fecal coliforms in the sewage treatment ponds of an urban wastewater center were studied after 20 months of sampling from five stations in these ponds. Isolation and identification of 247 Aeromonas strains were undertaken over four seasons at the inflow and outflow of this pond system. The hemolytic activity of these strains was determined. The Aeromonas spp. and the fecal coliform distributions showed seasonal cycles, the amplitude of which increased at distances further from the wastewater source, so that in the last pond there was an inversion of the Aeromonas spp. cycle in comparison with that of fecal coliforms. The main patterns in these cycles occurred simultaneously at all stations, indicating control of these bacterial populations by seasonal factors (temperature, solar radiation, phytoplankton), the effects of which were different on each bacterial group. The analysis of the Aeromonas spp. population structure showed that, regardless of the season, Aeromonas caviae was the dominant species at the pond system inflow. However at the outflow the Aeromonas spp. population was dominated by A. caviae in winter, whereas Aeromonas sobria was the dominant species in the treated effluent from spring to fall. Among the Aeromonas hydrophila and A. sobria strains, 100% produced hemolysin; whereas among the A. caviae strains, 96% were nonhemolytic. Images PMID:2389929

  12. Cytotoxic activity of Aeromonas hydrophila.

    PubMed Central

    Donta, S T; Haddow, A D

    1978-01-01

    Most strains of Aeromonas hydrophila tested demonstrated cytotoxic activity on several tissue-cultured cell lines. The cytotoxin is heat-labile, non-dialyzable, and immunologically distinct from that of Shigella dysenteriae and Clostridium perfringens. None of the aeromonas isolates was found to be enterotoxigenic by either tissue culture or rabbit ileal loop assays. Images PMID:711344

  13. 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

  14. Translocated effectors of Yersinia

    PubMed Central

    Matsumoto, Hiroyuki; Young, Glenn M.

    2009-01-01

    Summary Currently, all known translocated effectors of Yersinia are delivered into host cells by type III secretion systems (T3SSs). Pathogenic Yersinia maintain the plasmid-encoded Ysc T3SS for the specific delivery of the well-studied Yop effectors. New horizons for effector biology have opened with the discovery of the Ysps of Y. enterocolitica Biovar 1B, which are translocated into host cells by the chromosome-endoded Ysa T3SS. The reported arsenal of effectors is likely to expand since genomic analysis has revealed gene-clusters in some Yersinia that code for other T3SSs. These efforts also revealed possible type VI secretion (T6S) systems, which may indicate translocation of effectors occurs by multiple mechanisms. PMID:19185531

  15. Evidence of Increased Antibiotic Resistance in Phylogenetically-Diverse Aeromonas Isolates from Semi-Intensive Fish Ponds Treated with Antibiotics

    PubMed Central

    Patil, Hemant J.; Benet-Perelberg, Ayana; Naor, Alon; Smirnov, Margarita; Ofek, Tamir; Nasser, Ahmed; Minz, Dror; Cytryn, Eddie

    2016-01-01

    The genus Aeromonas is ubiquitous in aquatic environments encompassing a broad range of fish and human pathogens. Aeromonas strains are known for their enhanced capacity to acquire and exchange antibiotic resistance genes and therefore, are frequently targeted as indicator bacteria for monitoring antimicrobial resistance in aquatic environments. This study evaluated temporal trends in Aeromonas diversity and antibiotic resistance in two adjacent semi-intensive aquaculture facilities to ascertain the effects of antibiotic treatment on antimicrobial resistance. In the first facility, sulfadiazine-trimethoprim was added prophylactically to fingerling stocks and water column-associated Aeromonas were monitored periodically over an 11-month fish fattening cycle to assess temporal dynamics in taxonomy and antibiotic resistance. In the second facility, Aeromonas were isolated from fish skin ulcers sampled over a 3-year period and from pond water samples to assess associations between pathogenic strains to those in the water column. A total of 1200 Aeromonas isolates were initially screened for sulfadiazine resistance and further screened against five additional antimicrobials. In both facilities, strong correlations were observed between sulfadiazine resistance and trimethoprim and tetracycline resistances, whereas correlations between sulfadiazine resistance and ceftriaxone, gentamicin, and chloramphenicol resistances were low. Multidrug resistant strains as well as sul1, tetA, and intI1 gene-harboring strains were significantly higher in profiles sampled during the fish cycle than those isolated prior to stocking and these genes were extremely abundant in the pathogenic strains. Five phylogenetically distinct Aeromonas clusters were identified using partial rpoD gene sequence analysis. Interestingly, prior to fingerling stocking the diversity of water column strains was high, and representatives from all five clusters were identified, including an A. salmonicida cluster

  16. The FlgT Protein Is Involved in Aeromonas hydrophila Polar Flagella Stability and Not Affects Anchorage of Lateral Flagella

    PubMed Central

    Merino, Susana; Tomás, Juan M.

    2016-01-01

    Aeromonas hydrophila sodium-driven polar flagellum has a complex stator-motor. Consist of two sets of redundant and non-exchangeable proteins (PomA/PomB and PomA2/PomB2), which are homologs to other sodium-conducting polar flagellum stator motors; and also two essential proteins (MotX and MotY), that they interact with one of those two redundant pairs of proteins and form the T-ring. In this work, we described an essential protein for polar flagellum stability and rotation which is orthologs to Vibrio spp. FlgT and it is encoded outside of the A. hydrophila polar flagellum regions. The flgT was present in all mesophilic Aeromonas strains tested and also in the non-motile Aeromonas salmonicida. The A. hydrophila ΔflgT mutant is able to assemble the polar flagellum but is more unstable and released into the culture supernatant from the cell upon completion assembly. Presence of FlgT in purified polar hook-basal bodies (HBB) of wild-type strain was confirmed by Western blotting and electron microscopy observations showed an outer ring of the T-ring (H-ring) which is not present in the ΔflgT mutant. Anchoring and motility of proton-driven lateral flagella was not affected in the ΔflgT mutant and specific antibodies did not detect FlgT in purified lateral HBB of wild type strain. PMID:27507965

  17. Salmonella, Shigella, and Yersinia

    PubMed Central

    Dekker, John; Frank, Karen

    2015-01-01

    Synopsis Salmonella, Shigella, and Yersinia cause a well-characterized spectrum of disease in humans, ranging from asymptomatic carriage to hemorrhagic colitis and fatal typhoidal fever. These pathogens are responsible for millions of cases of food-borne illness in the U.S. each year, with substantial costs measured in hospitalizations and lost productivity. In the developing world, illness caused by these pathogens is not only more prevalent, but is also associated with a greater case-fatality rate. Classical methods for identification rely on selective media and serology, but newer methods based on mass spectrometry and PCR show great promise for routine clinical testing. PMID:26004640

  18. Potential of the Melanophore Pigment Response for Detection of Bacterial Toxicity ▿

    PubMed Central

    Dukovcic, Stephanie R.; Hutchison, Janine R.; Trempy, Janine E.

    2010-01-01

    Chromatophore cells have been investigated as potential biodetectors for function-based detection of chemically and biologically toxic substances. Oncorhynchus tshawytscha (chinook salmon) melanophores, a chromatophore cell type containing brown pigment, rapidly detect the salmonid pathogens Aeromonas salmonicida, Yersinia ruckeri, and Flavobacterium psychrophilum and the human pathogen Bacillus cereus. PMID:20952639

  19. The Genome of Spironucleus salmonicida Highlights a Fish Pathogen Adapted to Fluctuating Environments

    PubMed Central

    Xu, Feifei; Jerlström-Hultqvist, Jon; Einarsson, Elin; Ástvaldsson, Ásgeir; Svärd, Staffan G.; Andersson, Jan O.

    2014-01-01

    Spironucleus salmonicida causes systemic infections in salmonid fish. It belongs to the group diplomonads, binucleated heterotrophic flagellates adapted to micro-aerobic environments. Recently we identified energy-producing hydrogenosomes in S. salmonicida. Here we present a genome analysis of the fish parasite with a focus on the comparison to the more studied diplomonad Giardia intestinalis. We annotated 8067 protein coding genes in the ∼12.9 Mbp S. salmonicida genome. Unlike G. intestinalis, promoter-like motifs were found upstream of genes which are correlated with gene expression, suggesting a more elaborate transcriptional regulation. S. salmonicida can utilise more carbohydrates as energy sources, has an extended amino acid and sulfur metabolism, and more enzymes involved in scavenging of reactive oxygen species compared to G. intestinalis. Both genomes have large families of cysteine-rich membrane proteins. A cluster analysis indicated large divergence of these families in the two diplomonads. Nevertheless, one of S. salmonicida cysteine-rich proteins was localised to the plasma membrane similar to G. intestinalis variant-surface proteins. We identified S. salmonicida homologs to cyst wall proteins and showed that one of these is functional when expressed in Giardia. This suggests that the fish parasite is transmitted as a cyst between hosts. The extended metabolic repertoire and more extensive gene regulation compared to G. intestinalis suggest that the fish parasite is more adapted to cope with environmental fluctuations. Our genome analyses indicate that S. salmonicida is a well-adapted pathogen that can colonize different sites in the host. PMID:24516394

  20. Homology analysis of pathogenic Yersinia species Yersinia enterocolitica, Yersinia pseudotuberculosis, and Yersinia pestis based on multilocus sequence typing.

    PubMed

    Duan, Ran; Liang, Junrong; Shi, Guoxiang; Cui, Zhigang; Hai, Rong; Wang, Peng; Xiao, Yuchun; Li, Kewei; Qiu, Haiyan; Gu, Wenpeng; Du, Xiaoli; Jing, Huaiqi; Wang, Xin

    2014-01-01

    We developed a multilocus sequence typing (MLST) scheme and used it to study the population structure and evolutionary relationships of three pathogenic Yersinia species. MLST of these three Yersinia species showed a complex of two clusters, one composed of Yersinia pseudotuberculosis and Yersinia pestis and the other composed of Yersinia enterocolitica. Within the first cluster, the predominant Y. pestis sequence type 90 (ST90) was linked to Y. pseudotuberculosis ST43 by one locus difference, and 81.25% of the ST43 strains were from serotype O:1b, supporting the hypothesis that Y. pestis descended from the O:1b serotype of Y. pseudotuberculosis. We also found that the worldwide-prevalent serotypes O:1a, O:1b, and O:3 were predominated by specific STs. The second cluster consisted of pathogenic and nonpathogenic Y. enterocolitica strains, two of which may not have identical STs. The pathogenic Y. enterocolitica strains formed a relatively conserved group; most strains clustered within ST186 and ST187. Serotypes O:3, O:8, and O:9 were separated into three distinct blocks. Nonpathogenic Y. enterocolitica STs were more heterogeneous, reflecting genetic diversity through evolution. By providing a better and effective MLST procedure for use with the Yersinia community, valuable information and insights into the genetic evolutionary differences of these pathogens were obtained.

  1. Homology analysis and cross-immunogenicity of OmpA from pathogenic Yersinia enterocolitica, Yersinia pseudotuberculosis and Yersinia pestis.

    PubMed

    Chen, Yuhuang; Duan, Ran; Li, Xu; Li, Kewei; Liang, Junrong; Liu, Chang; Qiu, Haiyan; Xiao, Yuchun; Jing, Huaiqi; Wang, Xin

    2015-12-01

    The outer membrane protein A (OmpA) is one of the intra-species conserved proteins with immunogenicity widely found in the family of Enterobacteriaceae. Here we first confirmed OmpA is conserved in the three pathogenic Yersinia: Yersinia pestis, Yersinia pseudotuberculosis and pathogenic Yersinia enterocolitica, with high homology at the nucleotide level and at the amino acid sequence level. The identity of ompA sequences for 262 Y. pestis strains, 134 Y. pseudotuberculosis strains and 219 pathogenic Y. enterocolitica strains are 100%, 98.8% and 97.7% similar. The main pattern of OmpA of pathogenic Yersinia are 86.2% and 88.8% identical at the nucleotide and amino acid sequence levels, respectively. Immunological analysis showed the immunogenicity of each OmpA and cross-immunogenicity of OmpA for pathogenic Yersinia where OmpA may be a vaccine candidate for Y. pestis and other pathogenic Yersinia.

  2. Characterization of integrons and tetracycline resistance determinants in Aeromonas spp. isolated from South African aquaculture systems.

    PubMed

    Jacobs, Liezl; Chenia, Hafizah Y

    2007-03-20

    An increasing incidence of multidrug resistance amongst Aeromonas spp. isolates, which are both fish pathogens and emerging opportunistic human pathogens, has been observed worldwide. This can be attributed to the horizontal transfer of mobile genetic elements, viz.: plasmids and class 1 integrons. The antimicrobial susceptibilities of 37 Aeromonas spp. isolates, from tilapia, trout and koi aquaculture systems, were determined by disc-diffusion testing. The plasmid content of each isolate was examined using the alkaline lysis protocol. Tet determinant type was determined by amplification using two degenerate primer sets and subsequent HaeIII restriction. The presence of integrons was determined by PCR amplification of three integrase genes, as well as gene cassettes, and the qacEDelta1-sulI region. Thirty-seven Aeromonas spp. isolates were differentiated into six species by aroA PCR-RFLP, i.e., A. veronii biovar sobria, A. hydrophila, A. encheleia, A. ichtiosoma, A. salmonicida, and A. media. High levels of resistance to tetracycline (78.3%), amoxicillin (89.2%), and augmentin (86.5%) were observed. Decreased susceptibility to erythromycin was observed for 67.6% of isolates. Although 45.9% of isolates displayed nalidixic acid resistance, majority of isolates were susceptible to the fluoroquinolones. The MAR index ranged from 0.12 to 0.59, with majority of isolates indicating high-risk contamination originating from humans or animals where antibiotics are often used. Plasmids were detected in 21 isolates, with 14 of the isolates displaying multiple plasmid profiles. Single and multiple class A family Tet determinants were observed in 27% and 48.7% of isolates, respectively, with Tet A being the most prevalent Tet determinant type. Class 1 integron and related structures were amplified and carried different combinations of the antibiotic resistance gene cassettes ant(3'')Ia, aac(6')Ia, dhfr1, oxa2a and/or pse1. Class 2 integrons were also amplified, but the

  3. 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...

  4. 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

  5. Molecular cloning, nucleotide sequence, and expression in Escherichia coli of a hemolytic toxin (aerolysin) gene from Aeromonas trota

    SciTech Connect

    Khan, A.A.; Kim, E.; Cerniglia, C.E.

    1998-07-01

    Aeromonas trota AK2, which was derived from ATCC 49659 and produces the extracellular pore-forming hemolytic toxin aerolysin, was mutagenized with the transposon mini-Tn5Km1 to generate a hemolysin-deficient mutant, designated strain AK253. Southern blotting data indicated that an 8.7-kb NotI fragment of the genomic DNA of strain AK253 contained the kanamycin resistance gene of mini-Tn5Km1. The 8.7-kb NotI DNA fragment was cloned into the vector pGEM5Zf({minus}) by selecting for kanamycin resistance, and the resultant clone, pAK71, showed aerolysin activity in Escherichia coli JM109. The nucleotide sequence of the aerA gene, located on the 1.8-kb ApaI-EcoRI fragment, was determined to consist of 1,479 bp and to have an ATG initiation codon and a TAA termination codon. An in vitro coupled transcription-translation analysis of the 1.8-kb region suggested that the aerA gene codes for a 54-kDa protein, in agreement with nucleotide sequence data. The deduced amino acid sequence of the aerA gene product of A. trota exhibited 99% homology with the amino acid sequence of the aerA product of Aeromonas sobria AB3 and 57% homology with the amino acid sequences of the products of the aerA genes of Aeromonas salmonicida 17-2 and A. sobria 33.

  6. Environmental Regulation of Yersinia Pathophysiology

    PubMed Central

    Chen, Shiyun; Thompson, Karl M.; Francis, Matthew S.

    2016-01-01

    Hallmarks of Yersinia pathogenesis include the ability to form biofilms on surfaces, the ability to establish close contact with eukaryotic target cells and the ability to hijack eukaryotic cell signaling and take over control of strategic cellular processes. Many of these virulence traits are already well-described. However, of equal importance is knowledge of both confined and global regulatory networks that collaborate together to dictate spatial and temporal control of virulence gene expression. This review has the purpose to incorporate historical observations with new discoveries to provide molecular insight into how some of these regulatory mechanisms respond rapidly to environmental flux to govern tight control of virulence gene expression by pathogenic Yersinia. PMID:26973818

  7. Experimental induction of motile Aeromonas septicemia in channel catfish by waterborne challenge with virulent Aeromonas hydrophila

    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 catfish aquaculture in the Southeastern United States. Predisposing conditions leading to vAh infection in catfish were however largely unknown. The objective of thi...

  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. [The occurrence of Escherichia coli, Aeromonas hydrophila, Plesiomonas shigelloides and Clostridium perfringens in the intestinal flora of gray herons (Ardea cinerea)].

    PubMed

    Glünder, G

    1989-05-01

    The flora of the large intestine of 92 grey herons was examined for the frequency of aerobic and microaerobic growing bacteria. Clostridium perfringens, Aeromonas hydrophila, Plesiomonas shigelloides and E. coli were isolated from 55%, 48%, 14% and 35% of the birds, respectively. It could be demonstrated that the findings of these bacteria in the intestinal flora are depending on the age of the birds. The percentage of carriers of Clostridium perfringens, Aeromonas hydrophila and Plesiomonas shigelloides was highest in nestlings younger than 18 days, less high in older nestlings and lowest in adult grey herons. Contrary to those bacteria, E. coli was found more often in the intestinal flora at increasing age of the birds. Salmonella spp. were isolated from 6 birds. Two birds yielded positive for Yersinia enterocolitica and Campylobacter spp., respectively. Other aerobic and microaerobic bacteria play a less significant role as part of the intestinal flora.

  10. Aeromonas flagella and colonisation mechanisms.

    PubMed

    Lowry, Rebecca; Balboa, Sabela; Parker, Jennifer L; Shaw, Jonathan G

    2014-01-01

    Aeromonas species are inhabitants of aquatic environments and are able to cause disease in humans and fish among other animals. In aquaculture, they are responsible for the economically important diseases of furunculosis and motile Aeromonas septicaemia (MAS). Whereas gastroenteritis and wound infections are the major human diseases associated with the genus. As they inhabit and survive in diverse environments, aeromonads possess a wide range of colonisation factors. The motile species are able to swim in liquid environments through the action of a single polar flagellum, the flagellin subunits of which are glycosylated; although essential for function the biological role of glycan addition is yet to be determined. Approximately 60% of aeromonads possess a second lateral flagella system that is expressed in viscous environments for swarming over surfaces; both flagellar systems have been shown to be important in the initial colonisation of surfaces. Subsequently, other non-flagellar colonisation factors are employed; these can be both filamentous and non-filamentous. The aeromonads possess a number of fimbrial systems with the bundle-forming MSHA type IV pilus system, having a major role in human cell adherence. Furthermore, a series of outer-membrane proteins have also been implicated in the aeromonad adhesion process. A number of strains are also capable of cell invasion and that maybe linked with the more invasive diseases of bacteraemia or wound infections. These strains employ cell surface factors that allow the colonisation of these niches that protect them from the host's immune system such as S-layers, capsules or particular lipopolysaccharides.

  11. Recombinant expression and purification of an ATP-dependent DNA ligase from Aliivibrio salmonicida.

    PubMed

    Williamson, Adele; Pedersen, Hege

    2014-05-01

    The genome of the psychrophilic fish-pathogen Aliivibrio salmonicida encodes a putative ATP-dependent DNA ligase in addition to a housekeeping NAD-dependent enzyme. In order to study the structure and activity of the ATP dependent ligase in vitro we have undertaken its recombinant production and purification from an Escherichia coli based expression system. Expression and purification of this protein presented two significant challenges. First, the gene product was moderately toxic to E. coli cells, second it was necessary to remove the large amounts of E. coli DNA present in bacterial lysates without contamination of the protein preparation by nucleases which might interfere with future assaying. The toxicity problem was overcome by fusion of the putative ligase to large solubility tags such as maltose-binding protein (MBP) or Glutathione-S-transferase (GST), and DNA was removed by treatment with a nuclease which could be inhibited by reducing agents. As the A. salmonicida ATP-dependent DNA ligase gene encodes a predicted leader peptide, both the full-length and mature forms of the protein were produced. Both possessed ATP-dependent DNA ligase activity, but the truncated form was significantly more active. Here we detail the first reported production, purification and preliminary characterization of active A. salmonicida ATP-dependent DNA ligase.

  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. Aeromonas aquariorum Is Widely Distributed in Clinical and Environmental Specimens and Can Be Misidentified as Aeromonas hydrophila▿†

    PubMed Central

    Aravena-Román, Max; Harnett, Gerald B.; Riley, Thomas V.; Inglis, Timothy J. J.; Chang, Barbara J.

    2011-01-01

    Genotypic characterization of 215 Aeromonas strains (143 clinical, 52 environmental, and 20 reference strains) showed that Aeromonas aquariorum (60 strains, 30.4%) was the most frequently isolated species in clinical and water samples and could be misidentified as Aeromonas hydrophila by phenotypic methods. PMID:21697316

  14. Characterization of Aeromonas hydrophila Wound Pathotypes by Comparative Genomic and Functional Analyses of Virulence Genes

    PubMed Central

    Grim, Christopher J.; Kozlova, Elena V.; Sha, Jian; Fitts, Eric C.; van Lier, Christina J.; Kirtley, Michelle L.; Joseph, Sandeep J.; Read, Timothy D.; Burd, Eileen M.; Tall, Ben D.; Joseph, Sam W.; Horneman, Amy J.; Chopra, Ashok K.; Shak, Joshua R.

    2013-01-01

    ABSTRACT Aeromonas hydrophila has increasingly been implicated as a virulent and antibiotic-resistant etiologic agent in various human diseases. In a previously published case report, we described a subject with a polymicrobial wound infection that included a persistent and aggressive strain of A. hydrophila (E1), as well as a more antibiotic-resistant strain of A. hydrophila (E2). To better understand the differences between pathogenic and environmental strains of A. hydrophila, we conducted comparative genomic and functional analyses of virulence-associated genes of these two wound isolates (E1 and E2), the environmental type strain A. hydrophila ATCC 7966T, and four other isolates belonging to A. aquariorum, A. veronii, A. salmonicida, and A. caviae. Full-genome sequencing of strains E1 and E2 revealed extensive differences between the two and strain ATCC 7966T. The more persistent wound infection strain, E1, harbored coding sequences for a cytotoxic enterotoxin (Act), a type 3 secretion system (T3SS), flagella, hemolysins, and a homolog of exotoxin A found in Pseudomonas aeruginosa. Corresponding phenotypic analyses with A. hydrophila ATCC 7966T and SSU as reference strains demonstrated the functionality of these virulence genes, with strain E1 displaying enhanced swimming and swarming motility, lateral flagella on electron microscopy, the presence of T3SS effector AexU, and enhanced lethality in a mouse model of Aeromonas infection. By combining sequence-based analysis and functional assays, we characterized an A. hydrophila pathotype, exemplified by strain E1, that exhibited increased virulence in a mouse model of infection, likely because of encapsulation, enhanced motility, toxin secretion, and cellular toxicity. PMID:23611906

  15. Seasonal prevalence of nosocomial Aeromonas hydrophila infection related to aeromonas in hospital water.

    PubMed

    Picard, B; Goullet, P

    1987-09-01

    A seasonal variation in nosocomial Aeromonas hydrophila infection was correlated with the number of aeromonas in the hospital water supply. The high summer prevalence of A. hydrophila infection coincided with periods when water counts from storage tanks were highest. The waterborne origin of these infections highlights the importance of maintaining clean water supplies, especially where storage tanks are used. Monitoring A. hydrophila in hospital water, particularly during the summer months, may prove helpful.

  16. Microgravity Effects on Yersinia Pestis Virulence

    NASA Astrophysics Data System (ADS)

    Lawal, A.; Abogunde, O.; Jejelowo, O.; Rosenzweig, J.-A.

    2010-04-01

    Microgravity effects on Yersinia pestis proliferation, cold growth, and type three secretion system function were evaluated in macrophage cell infections, HeLa cell infections, and cold growth plate assays.

  17. A Novel lux Operon in the Cryptically Bioluminescent Fish Pathogen Vibrio salmonicida Is Associated with Virulence▿

    PubMed Central

    Nelson, Eric J.; Tunsjø, Hege S.; Fidopiastis, Pat M.; Sørum, Henning; Ruby, Edward G.

    2007-01-01

    The cold-water-fish pathogen Vibrio salmonicida expresses a functional bacterial luciferase but produces insufficient levels of its aliphatic-aldehyde substrate to be detectably luminous in culture. Our goals were to (i) better explain this cryptic bioluminescence phenotype through molecular characterization of the lux operon and (ii) test whether the bioluminescence gene cluster is associated with virulence. Cloning and sequencing of the V. salmonicida lux operon revealed that homologs of all of the genes required for luminescence are present: luxAB (luciferase) and luxCDE (aliphatic-aldehyde synthesis). The arrangement and sequence of these structural lux genes are conserved compared to those in related species of luminous bacteria. However, V. salmonicida strains have a novel arrangement and number of homologs of the luxR and luxI quorum-sensing regulatory genes. Reverse transcriptase PCR analysis suggests that this novel arrangement of quorum-sensing genes generates antisense transcripts that may be responsible for the reduced production of bioluminescence. In addition, infection with a strain in which the luxA gene was mutated resulted in a marked delay in mortality among Atlantic salmon relative to infection with the wild-type parent in single-strain challenge experiments. In mixed-strain competition between the luxA mutant and the wild type, the mutant was attenuated up to 50-fold. It remains unclear whether the attenuation results from a direct loss of luciferase or a polar disturbance elsewhere in the lux operon. Nevertheless, these findings document for the first time an association between a mutation in a structural lux gene and virulence, as well as provide a new molecular system to study Vibrio pathogenesis in a natural host. PMID:17277225

  18. Pan-genome analysis of Aeromonas hydrophila, Aeromonas veronii and Aeromonas caviae indicates phylogenomic diversity and greater pathogenic potential for Aeromonas hydrophila.

    PubMed

    Ghatak, Sandeep; Blom, Jochen; Das, Samir; Sanjukta, Rajkumari; Puro, Kekungu; Mawlong, Michael; Shakuntala, Ingudam; Sen, Arnab; Goesmann, Alexander; Kumar, Ashok; Ngachan, S V

    2016-07-01

    Aeromonas species are important pathogens of fishes and aquatic animals capable of infecting humans and other animals via food. Due to the paucity of pan-genomic studies on aeromonads, the present study was undertaken to analyse the pan-genome of three clinically important Aeromonas species (A. hydrophila, A. veronii, A. caviae). Results of pan-genome analysis revealed an open pan-genome for all three species with pan-genome sizes of 9181, 7214 and 6884 genes for A. hydrophila, A. veronii and A. caviae, respectively. Core-genome: pan-genome ratio (RCP) indicated greater genomic diversity for A. hydrophila and interestingly RCP emerged as an effective indicator to gauge genomic diversity which could possibly be extended to other organisms too. Phylogenomic network analysis highlighted the influence of homologous recombination and lateral gene transfer in the evolution of Aeromonas spp. Prediction of virulence factors indicated no significant difference among the three species though analysis of pathogenic potential and acquired antimicrobial resistance genes revealed greater hazards from A. hydrophila. In conclusion, the present study highlighted the usefulness of whole genome analyses to infer evolutionary cues for Aeromonas species which indicated considerable phylogenomic diversity for A. hydrophila and hitherto unknown genomic evidence for pathogenic potential of A. hydrophila compared to A. veronii and A. caviae.

  19. [Prevalence of Aeromonas spp. in surface water].

    PubMed

    Hernández, P; Rodríguez de García, R

    1997-03-01

    Some Aeromonas strains are well recognized enteropathogens according to microbiological, clinical, immunological and epidemiological evidence. The main source of infection seems to be untreated water, these microorganisms can be found in virtually all aquatic environments. Additionally, some Aeromonas, which include enterotoxigenic strains, are capable of rapid growth at 5 degrees C and even of producing toxins. Vegetable products irrigated with contaminated water may reach critical Aeromonas levels after being kept under refrigeration, this could represent a public health risk when they are consumed as uncooked salads. This study was pursued to evaluate such risk. Surface water samples were streaked on starch ampicillin and inositol-brilliant green-bile salts agar dishes. In addition, 100 ml of each sample were filtered through a 0.45 micron Millipore membrane filter. The filters were incubated on alkaline peptone water as enrichment media during 24 h at 35 degrees C. Enrichment broth was then streaked on the selective agars above mentioned. Isolates from both tests were identified using the API 20 E System. The prevalence of Aeromonas strains in the analyzed samples was 17.8%. A higher isolation rate was observed after the enrichment technique. Starch ampicillin agar showed a higher recuperation rate. A Veronii biotype sobria (formerly A. sobria) was isolated with higher frequency. Since this species has been associated with the greatest virulence, the use of contaminated water to irrigate vegetable products that are to be kept under refrigeration and consumed without ulterior cooking may represent a risk to the public health.

  20. Association of Aeromonas sobria with human infection.

    PubMed Central

    Daily, O P; Joseph, S W; Coolbaugh, J C; Walker, R I; Merrell, B R; Rollins, D M; Seidler, R J; Colwell, R R; Lissner, C R

    1981-01-01

    Fifteen Aeromonas isolates from various human infections and nine isolates from polluted water were identified as either Aeromonas hydrophila or Aeromonas sobria and examined for cytotoxigenicity, enterotoxigenicity, adherence to epithelial cells, and other virulence-associated factors, including proteases, lipases, elastases, and hemolysins. Two groups of organisms (I and II) were distinguishable based on differences in median lethal doses in mice and cytotoxicity for Y-1 adrenal cells. Group I clinical and environmental strains had median lethal doses of less than 10(7) colony-forming units, were cytotoxic, frequently possessed several virulence-associated factors, and had lysine decarboxylase-positive or Voges-Proskauer-positive phenotypes or both. Piliation of Aeromonas was associated strongly with ability to adhere to human buccal cells, and these characteristics were associated with group I strains. Group II clinical and environmental strains had median lethal doses of greater than or equal to 10(7) colony-forming units, were not cytotoxic, and usually were lysine decarboxylase negative or Voges-Proskauer negative or both. Clinical strains in group II exhibited enterotoxigenicity, which was not detected in group II environmental strains. A sobria was more frequently associated with human infections; 13 of the 15 clinical strains were A. sobria, and 2 were A. hydrophila. On the other hand, the majority of the environmental strains (seven of nine) were A. hydrophila. Images PMID:6112237

  1. MONITORING FOR AEROMONAS SPECIES AFTER TREATMENT WITH COMMON DRINKING WATER DISINFECTANTS

    EPA Science Inventory

    The sensitivity of Aeromonas spp. To free chlorine, chloramine and ultraviolet (UV) disinfection was determined. Aeromonas hydrophila is a contaminant listed on the USEPA's 1998 Contaminant Candidate List (CCL). Experiments using free chlorine indicated that the Aeromonas spp. ...

  2. Virulence factors in clinical and food isolates of Aeromonas species.

    PubMed

    Pin, C; Marín, M L; Selgas, M D; García, M L; Tormo, J; Casas, C

    1994-01-01

    Virulence factors were compared in 15 Aeromonas spp. isolated from faeces of patients with Aeromonas-associated gastroenteritis and in 81 strains isolated from food. Strains from food did not show differences in the distribution of virulence factors when compared with strains isolated from faeces. However, 88.8% of Aeromonas strains isolated from food were capable of producing possible virulence factors. Characterization of 28 autoagglutinating (AA+) Aeromonas spp. indicated that the human strains differed from the food strains in hemagglutinating and hemolytic capacities. These results suggest that autoagglutination associated with hemagglutinating and hemolytic capacities in food strains may be a helpful indicator of potential pathogenicity.

  3. 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

  4. The Genus Aeromonas: Taxonomy, Pathogenicity, and Infection

    PubMed Central

    Janda, J. Michael; Abbott, Sharon L.

    2010-01-01

    Summary: Over the past decade, the genus Aeromonas has undergone a number of significant changes of practical importance to clinical microbiologists and scientists alike. In parallel with the molecular revolution in microbiology, several new species have been identified on a phylogenetic basis, and the genome of the type species, A. hydrophila ATCC 7966, has been sequenced. In addition to established disease associations, Aeromonas has been shown to be a significant cause of infections associated with natural disasters (hurricanes, tsunamis, and earthquakes) and has been linked to emerging or new illnesses, including near-drowning events, prostatitis, and hemolytic-uremic syndrome. Despite these achievements, issues still remain regarding the role that Aeromonas plays in bacterial gastroenteritis, the extent to which species identification should be attempted in the clinical laboratory, and laboratory reporting of test results from contaminated body sites containing aeromonads. This article provides an extensive review of these topics, in addition to others, such as taxonomic issues, microbial pathogenicity, and antimicrobial resistance markers. PMID:20065325

  5. Incidence and virulence characteristics of Aeromonas spp. in fish

    PubMed Central

    Abd-El-Malek, Ashraf M.

    2017-01-01

    Aim: This study was conducted to evaluate the presence of Aeromonas spp. in raw and ready-to-eat (RTE) fish commonly consumed in Assiut city, Egypt, and to determine virulence factors due to they play a key role in their pathogenicity. Materials and Methods: A total of 125 samples of raw and RTE fish samples were taken from different fish markets and fish restaurants in Assiut Governorate and screened for the presence of Aeromonas spp. by enrichment on tryptic soy broth then incubated at 30°C for 24 h. Plating unto the sterile Petri dishes containing Aeromonas agar base to which Aeromonas selective supplement was added. The plates were incubated at 37°C for 24 h. Presumptive Aeromonas colonies were biochemically confirmed and analyzed for pathogenicity by hemolysin production, protease, and lipase detection. Results: The results indicated that raw fish were contaminated with Aeromonas spp. (40% in wild and 36% in cultured Nile tilapia). Regarding RTE, Aeromonas spp. could be isolated with the percentage of 16%, 28% and 20% in fried Bolti, grilled Bolti and fried Bayad, respectively. Out of 35 isolates obtained, 22 were categorized as Aeromonas hydrophila, 12 were classified as Aeromonas sobria and Aeromonas caviae were found in only one isolate. The virulence factors of Aeromonas spp. were detected and the results showed that all isolates produced of hemolysin (91.4%), protease (77.1%), and lipase enzyme (17.1%). Conclusion: This study indicates that the presence of A. hydrophila with virulence potential in fresh and RTE fish may be a major threat to public health. PMID:28246446

  6. [Bacteremia and meningitis caused by Yersinia spp].

    PubMed

    Robert, J; Moreno, A; Martínez, J A; Almela, M; Jiménez de Anta, M T; Soriano, E

    2000-07-01

    Yersinia spp infection in human people are increasing attention last thirty years. We have reviewed the bacteremia in our hospital last five years. Three episodes were Yersinia spp bacteremia. Presence of disease or predisponent therapy were present in most of episodes. All patients were more than seventy years old. The septic metastasis were present in all the cases: one with meningitis, other with liver abscess and one with septic arthritis. We have documented a good clinical evolution, though the mortality in different reports is around 50%. The election therapy for all episodes were cephalosporins, and in two cases we added quinolones.

  7. OVERVIEW: DISINFECTION OF HELICOBACTER PYLORI AND AEROMONAS SPECIES

    EPA Science Inventory

    Helicobacter pylori and Aeromonas hydrophila are contaminants listed on the USEPA's 1998 Contaminant Candidate List (CCL).The sensitivity of H. pylori to chlorine and of Aeromonas spp. to inactivation by free chlorine, chloramine and ultraviolet (UV) was examined. Selective and...

  8. Draft genome sequence of Aeromonas hydrophila TN97-08

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila is an opportunistic Gram-negative species causing disease in fish and mammals. The genus Aeromonas affects a variety of aquatic organisms and lives in diverse aquatic ecosystems (1). There are 39 A. hydrophila genomes currently available in GenBank. In the current study, we repo...

  9. Chitin degradation and metabolism by virulent Aeromonas hydropila

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila is the causal agent of motile Aeromonas septicemia (MAS) in catfish and other warm-water fishes. Severe outbreak of MAS caused by virulent A. hydrophila (vAh) was reported in 2009 in the Southeastern United States; the disease has since resulted in loss of millions of pounds of ...

  10. 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...

  11. 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...

  12. Isolation of Aeromonas spp. from an unchlorinated domestic water supply.

    PubMed Central

    Burke, V; Robinson, J; Gracey, M; Peterson, D; Meyer, N; Haley, V

    1984-01-01

    The recovery of Aeromonas spp. from the unchlorinated water supply for a Western Australian city of 21,000 people was monitored at several sampling points during a period of 1 year. Membrane filtration techniques were used to count colonies of Aeromonas spp., coliforms, and Escherichia coli in water sampled before entry to service reservoirs, during storage in service reservoirs, and in distribution systems. Aeromonas spp. were identified by subculture on blood agar with ampicillin, oxidase tests, and the use of Kaper medium and then were tested for production of enterotoxins and hemolysins. During the same period, two-thirds of all fecal specimens sent for microbiological examination were cultured on ampicillin-blood agar for Aeromonas spp. Recovery of Aeromonas spp. from water supplies at distribution points correlated with fecal isolations and continued during autumn and winter. Coliforms and E. coli were found most commonly in late summer to autumn. This pattern differs from the summer peak of Aeromonas isolations both from water and from patients with Aeromonas spp.-associated gastroenteritis in Perth, Western Australia, a city with a chlorinated domestic water supply. Of the Aeromonas strains from water, 61% were enterotoxigenic, and 64% produced hemolysins. PMID:6486783

  13. 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.

  14. 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

  15. Flagellar regulation in Yersinia ruckeri during infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The gram-negative Enterobacterium Yersinia ruckeri is the etiologic agent of enteric redmouth disease (ERM), a septicemia affecting primarily farmed rainbow trout (Oncorhynchus mykiss, Walbaum). Over the past decade, there has been an increase in the prevalence of non-motile variants of Y. ruckeri a...

  16. Yersinia adhesins: An arsenal for infection.

    PubMed

    Chauhan, Nandini; Wrobel, Agnieszka; Skurnik, Mikael; Leo, Jack C

    2016-10-01

    The Yersiniae are a group of Gram-negative coccobacilli inhabiting a wide range of habitats. The genus harbors three recognized human pathogens: Y. enterocolitica and Y. pseudotuberculosis, which both cause gastrointestinal disease, and Y. pestis, the causative agent of plague. These three organisms have served as models for a number of aspects of infection biology, including adhesion, immune evasion, evolution of pathogenic traits, and retracing the course of ancient pandemics. The virulence of the pathogenic Yersiniae is heavily dependent on a number of adhesin molecules. Some of these, such as the Yersinia adhesin A and invasin of the enteropathogenic species, and the pH 6 antigen of Y. pestis, have been extensively studied. However, genomic sequencing has uncovered a host of other adhesins present in these organisms, the functions of which are only starting to be investigated. Here, we review the current state of knowledge on the adhesin molecules present in the Yersiniae, and their functions and putative roles in the infection process.

  17. Medium for presumptive identification of Yersinia enterocolitica.

    PubMed

    Weagant, S D

    1983-02-01

    A medium, lysine-arginine-iron agar, was developed for the presumptive identification of Yersinia enterocolitica isolates. This medium was a modification of lysine-iron agar and allowed for the testing of five biochemical characteristics in a single tube medium. The reactions of Y. enterocolitica on this medium were reliable and distinctive. The medium significantly simplified the identification of Y. enterocolitica isolates.

  18. YERSINIA ENTEROCOLITICA: AN IMPORTANT HUMAN FOODBORNE PATHOGEN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yersinia enterocolitica is a Gram-negative microbe of public health importance and is under national FoodNet surveillance in the United States. The majority of human yersiniosis cases are foodborne. Consumption of dairy products (milk, ice cream), water, vegetables (tofu), and pork have been linke...

  19. Crystallization and preliminary X-ray diffraction analysis of a cold-adapted catalase from Vibrio salmonicida

    SciTech Connect

    Riise, Ellen Kristin; Lorentzen, Marit Sjo; Helland, Ronny; Willassen, Nils Peder

    2006-01-01

    Monoclinic (P2{sub 1}) crystals of a His-tagged form of V. salmonicida catalase without cofactor diffract X-rays to 1.96 Å. Catalase (EC 1.11.1.6) catalyses the breakdown of hydrogen peroxide to water and molecular oxygen. Recombinant Vibrio salmonicida catalase (VSC) possesses typical cold-adapted features, with higher catalytic efficiency, lower thermal stability and a lower temperature optimum than its mesophilic counterpart from Proteus mirabilis. Crystals of VSC were produced by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. The crystals belong to the monoclinic space group P2{sub 1}, with unit-cell parameters a = 98.15, b = 217.76, c = 99.28 Å, β = 110.48°. Data were collected to 1.96 Å and a molecular-replacement solution was found with eight molecules in the asymmetric unit.

  20. 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

  1. Aldohexuronic Acid Catabolism by a Soil Aeromonas

    PubMed Central

    Farmer, J. J.; Eagon, R. G.

    1969-01-01

    Bacteria which utilize mannuronic acid as an energy source were isolated from nature. One of the organisms, identified as a member of the genus Aeromonas, used glucuronate, galacturonate, and mannuronate as the sole source of carbon and energy. Glucuronate- and galacturonate-grown resting cells oxidized both glucuronate and galacturonate rapidly, but mannuronate slowly. Mannuronate-grown cells oxidized all three rapidly, with the rate of mannuronate utilization somewhat lower. Cell-free extracts from glucuronate-, galacturonate-, and mannuronate-grown Aeromonas C11-2B contained glucuronate and galacturonate isomerases, fructuronate, tagaturonate, and mannuronate reductases, and mannonate and altronate dehydratases, with the exception of glucuronate-grown cells which lacked altronate dehydratase. Thus, the pathway for glucuronate and galacturonate catabolism for Aeromonas was identical to Escherichia coli. Glucuronate and galacturonate were isomerized to d-fructuronate and d-tagaturonate which were then reduced by reduced nicotinamide adenine dinucleotide to d-mannonate and d-altronate, respectively. The hexonic acids were dehydrated to 2-keto-3-deoxy gluconate which was phosphorylated by adenosine triphosphate to 2-keto-3-deoxy-6-phospho gluconate. The latter was then cleaved to pyruvate and glyceraldehyde-3-phosphate. Mannuronate was reduced directly to d-mannonate by a reduced nicotinamide adenine dinucleotide phosphate-linked oxidoreductase. d-Mannonate was then further broken down as in the glucuronate pathway. The mannuronate reducing enzyme, for which the name d-mannonate:nicotinamide adenine dinucleotide (phosphate) oxidoreductase (d-mannuronate-forming) was proposed, was shown to be distinct from altronate and mannoate oxidoreductases. This is the first report of a bacterial oxidoreductase which reduces an aldohexuronic acid to a hexonic acid. The enzyme should prove to be a useful analytical tool for determining mannuronate in the presence of other uronic

  2. Identification of Yersinia Species by the Vitek GNI Card

    PubMed Central

    Linde, Hans-Jörg; Neubauer, Heinrich; Meyer, Hermann; Aleksic, Stojanca; Lehn, Norbert

    1999-01-01

    The Vitek GNI card was used to identify 212 isolates of 10 Yersinia species. Identification was correct for 96.3% of the isolates (156 of 162) to the genus level and for 57.4% of the isolates (93 of 162) to the species level for Yersinia spp. listed in the Vitek database. We recommend additional identification methods for isolates assigned to the genus Yersinia by the Vitek system. PMID:9854094

  3. Microevolution and History of the Plague Bacillus, Yersinia pestis

    DTIC Science & Technology

    2007-11-02

    recognized by the three methods, and we propose an evolutionary tree for these populations, rooted on Yersinia pseudotuberculosis. The tree in- vokes...were recognized by the three methods, and we propose an evolutionary tree for these populations, rooted on Yersinia pseudotuberculosis. The tree invokes...Microevolution and history of the plague bacillus, Yersinia pestis Mark Achtman*†, Giovanna Morelli*, Peixuan Zhu*‡, Thierry Wirth*§, Ines Diehl

  4. Cellular components of probiotics control Yersinia ruckeri infection in rainbow trout, Oncorhynchus mykiss (Walbaum).

    PubMed

    Abbass, A; Sharifuzzaman, S M; Austin, B

    2010-01-01

    Subcellular components of the probiotics Aeromonas sobria GC2 and Bacillus subtilis JB-1, when administered to rainbow trout, Oncorhynchus mykiss, conferred protection against a new biogroup of Yersinia ruckeri. Thus, intraperitoneal or intramuscular injection of rainbow trout with cell wall proteins (CWPs), outer membrane proteins (OMPs), lipopolysaccharides (LPS), whole cell proteins (WCPs) and live cells followed by challenge on day 8 with Y. ruckeri led to 80-100% survival compared with 10% survival in the controls. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles of WCPs and OMPs from GC2 had 10 and 5 variable protein bands in comparison to 11 and 5 bands in the WCPs and CWPs from JB-1. Proteomic analyses were employed following SDS-PAGE to categorize one dominant protein of 104.7 kDa from the CWPs of JB-1 and equated it with 'Bacillus spp. endoglucanase' with a Mascot score >69. These results point to the potential of using cellular components of probiotics for protection of fish against bacterial diseases.

  5. Bacterial cell surface structures in Yersinia enterocolitica.

    PubMed

    Białas, Nataniel; Kasperkiewicz, Katarzyna; Radziejewska-Lebrecht, Joanna; Skurnik, Mikael

    2012-06-01

    Yersinia enterocolitica is a widespread member of the family of Enterobacteriaceae that contains both non-virulent and virulent isolates. Pathogenic Y. enterocolitica strains, especially belonging to serotypes O:3, O:5,27, O:8 and O:9 are etiologic agents of yersiniosis in animals and humans. Y. enterocolitica cell surface structures that play a significant role in virulence have been subject to many investigations. These include outer membrane (OM) glycolipids such as lipopolysaccharide (LPS) and enterobacterial common antigen (ECA) and several cell surface adhesion proteins present only in virulent Y. enterocolitica, i.e., Inv, YadA and Ail. While the yadA gene is located on the Yersinia virulence plasmid the Ail, Inv, LPS and ECA are chromosomally encoded. These structures ensure the correct architecture of the OM, provide adhesive properties as well as resistance to antimicrobial peptides and to host innate immune response mechanisms.

  6. Clinical significance of Aeromonas species isolated from patients with diarrhea.

    PubMed

    Moyer, N P

    1987-11-01

    A total of 248 strains of Aeromonas spp. were isolated from 3,334 human fecal specimens submitted to a state public health laboratory over a 2-year period to be cultured for enteric pathogens. Cary-Blair transport medium, blood ampicillin agar, and alkaline peptone water enrichment provided optimal recovery of Aeromonas spp. A questionnaire requesting clinical and epidemiological information was sent to physicians, who submitted stool samples for testing, with each laboratory report for 107 consecutive stool isolates of Aeromonas spp. The 56 questionnaires which were completed and returned were analyzed to determine the seasonal distribution of illness and the age and sex distribution of patients; characteristic symptoms; and predisposing factors for gastrointestinal disease caused by Aeromonas spp. It was concluded that some A. hydrophila, A. sobria, and A. caviae strains are capable of causing diarrhea and that antibiotic therapy and the drinking of untreated water are significant risk factors for susceptible hosts.

  7. ANALYSIS OF AEROMONAS BY MASS SPECTROMETRY: SPECIATION AND VIRULENCE FACTORS

    EPA Science Inventory

    Introduction:

    A number of bacteria, including Aeromonas hydrophila, are listed on the Environmental Protection Agency's 1998 Contaminant Candidate List (CCL) as research needs. One research priority designated by the CCL is the identification of virulence activity facto...

  8. Clinical significance of Aeromonas species isolated from patients with diarrhea.

    PubMed Central

    Moyer, N P

    1987-01-01

    A total of 248 strains of Aeromonas spp. were isolated from 3,334 human fecal specimens submitted to a state public health laboratory over a 2-year period to be cultured for enteric pathogens. Cary-Blair transport medium, blood ampicillin agar, and alkaline peptone water enrichment provided optimal recovery of Aeromonas spp. A questionnaire requesting clinical and epidemiological information was sent to physicians, who submitted stool samples for testing, with each laboratory report for 107 consecutive stool isolates of Aeromonas spp. The 56 questionnaires which were completed and returned were analyzed to determine the seasonal distribution of illness and the age and sex distribution of patients; characteristic symptoms; and predisposing factors for gastrointestinal disease caused by Aeromonas spp. It was concluded that some A. hydrophila, A. sobria, and A. caviae strains are capable of causing diarrhea and that antibiotic therapy and the drinking of untreated water are significant risk factors for susceptible hosts. PMID:3693537

  9. Aeromonas hydrophila: variability in biochemical characteristics of environmental isolates.

    PubMed

    Okpokwasili, G C

    1991-01-01

    A total of 161 strains, including 144 aeromonads, of which 100 had been isolated from water and sediment samples from the Chesapeake Bay, five clinical and 33 Anacostia River isolates of Aeromonas hydrophila, six Aeromonas sobria, and ten reference cultures were examined in a numerical taxonomy study in which each of the strains were examined for 56 unit characters. Similarity between strains was computed using the simple matching (SSM) and Jaccard (SJ) coefficients. The strains were clustered by unweighted average linkage and single linkage algorithms. Results of all analyses yielded similar clusterings of strains. Of the 161 strains included in the study, 148 were recovered in seven major clusters. A large cluster of Aeromonas hydrophila yielded two sub-clusters. From the results of the taxonomic analysis it is concluded that several biovars of Aeromonas hydrophila can be isolated from the aquatic environment, but geographical or site specific distribution of the biovars could not be detected.

  10. Oral vaccination against plague using Yersinia pseudotuberculosis.

    PubMed

    Demeure, Christian E; Derbise, Anne; Carniel, Elisabeth

    2017-04-01

    Yersinia pestis, the agent of plague, is among the deadliest bacterial pathogens affecting humans, and is a potential biological weapon. Because antibiotic resistant strains of Yersinia pestis have been observed or could be engineered for evil use, vaccination against plague might become the only means to reduce mortality. Although plague is re-emerging in many countries, a vaccine with worldwide license is currently lacking. The vaccine strategy described here is based on an oral vaccination with an attenuated strain of Yersinia pseudotuberculosis. Indeed, this species is genetically almost identical to Y. pestis, but has a much lower pathogenicity and a higher genomic stability. Gradual modifications of the wild-type Yersinia pseudotuberculosis strain IP32953 were performed to generate a safe and immunogenic vaccine. Genes coding for three essential virulence factors were deleted from this strain. To increase cross-species immunogenicity, an F1-encapsulated Y. pseudotuberculosis strain was then generated. For this, the Y. pestis caf operon, which encodes F1, was inserted first on a plasmid, and subsequently into the chromosome. The successive steps achieved to reach maximal vaccine potential are described, and how each step affected bacterial virulence and the development of a protective immune response is discussed. The final version of the vaccine, named VTnF1, provides a highly efficient and long-lasting protection against both bubonic and pneumonic plague after a single oral vaccine dose. Since a Y. pestis strain deprived of F1 exist or could be engineered, we also analyzed the protection conferred by the vaccine against such strain and found that it also confers full protection against the two forms of plague. Thus, the properties of VTnF1 makes it one of the most efficient candidate vaccine for mass vaccination in tropical endemic areas as well as for populations exposed to bioterrorism.

  11. The Yersinia pseudotuberculosis complex: characterization and delineation of a new species, Yersinia wautersii.

    PubMed

    Savin, Cyril; Martin, Liliane; Bouchier, Christiane; Filali, Sofia; Chenau, Jérôme; Zhou, Zhemin; Becher, François; Fukushima, Hiroshi; Thomson, Nicholas R; Scholz, Holger C; Carniel, Elisabeth

    2014-05-01

    The genus Yersinia contains three species pathogenic for humans, one of which is the enteropathogen Yersinia pseudotuberculosis. A recent analysis by Multi Locus Sequence Typing (MLST) of the 'Y. pseudotuberculosis complex' revealed that this complex comprises three distinct populations: the Y. pestis/Y. pseudotuberculosis group, the recently described species Yersinia similis, and a third not yet characterized population designated 'Korean Group', because most strains were isolated in Korea. The aim of this study was to perform an in depth phenotypic and genetic characterization of the three populations composing the Y. pseudotuberculosis complex (excluding Y. pestis, which belonged to the Y. pseudotuberculosis cluster in the MLST analysis). Using a set of strains representative of each group, we found that the three populations had close metabolic properties, but were nonetheless distinguishable based on D-raffinose and D-melibiose fermentation, and on pyrazinamidase activity. Moreover, high-resolution electrospray mass spectrometry highlighted protein peaks characteristic of each population. Their 16S rRNA gene sequences shared high identity (≥99.5%), but specific nucleotide signatures for each group were identified. Multi-Locus Sequence Analysis also identified three genetically closely related but distinct populations. Finally, an Average Nucleotide Identity (ANI) analysis performed after sequencing the genomes of a subset of strains of each group also showed that intragroup identity (average for each group ≥99%) was higher than intergroup diversity (94.6-97.4%). Therefore, all phenotypic and genotypic traits studied concurred with the initial MLST data indicating that the Y. pseudotuberculosis complex comprises a third and clearly distinct population of strains forming a novel Yersinia species that we propose to designate Yersinia wautersii sp. nov. The isolation of some strains from humans, the detection of virulence genes (on the pYV and pVM82 plasmids

  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. Regulatory principles governing Salmonella and Yersinia virulence

    PubMed Central

    Erhardt, Marc; Dersch, Petra

    2015-01-01

    Enteric pathogens such as Salmonella and Yersinia evolved numerous strategies to survive and proliferate in different environmental reservoirs and mammalian hosts. Deciphering common and pathogen-specific principles for how these bacteria adjust and coordinate spatiotemporal expression of virulence determinants, stress adaptation, and metabolic functions is fundamental to understand microbial pathogenesis. In order to manage sudden environmental changes, attacks by the host immune systems and microbial competition, the pathogens employ a plethora of transcriptional and post-transcriptional control elements, including transcription factors, sensory and regulatory RNAs, RNAses, and proteases, to fine-tune and control complex gene regulatory networks. Many of the contributing global regulators and the molecular mechanisms of regulation are frequently conserved between Yersinia and Salmonella. However, the interplay, arrangement, and composition of the control elements vary between these closely related enteric pathogens, which generate phenotypic differences leading to distinct pathogenic properties. In this overview we present common and different regulatory networks used by Salmonella and Yersinia to coordinate the expression of crucial motility, cell adhesion and invasion determinants, immune defense strategies, and metabolic adaptation processes. We highlight evolutionary changes of the gene regulatory circuits that result in different properties of the regulatory elements and how this influences the overall outcome of the infection process. PMID:26441883

  14. CHROMagar Yersinia, a New Chromogenic Agar for Screening of Potentially Pathogenic Yersinia enterocolitica Isolates in Stools

    PubMed Central

    Renaud, Nicolas; Lecci, Laetitia; Courcol, René J.; Simonet, Michel

    2013-01-01

    CHROMagar Yersinia (CAY) is a new chromogenic medium for the presumptive detection of virulent Yersinia enterocolitica in stools. Based on a comparative analysis of 1,494 consecutive stools from hospitalized patients, CAY was found to be just as sensitive as the reference medium (cefsulodin-irgasan-novobiocin agar) but was significantly more specific and had a very low false-positive rate. CAY reduces the workload (and thus costs) for stool analysis and can therefore be recommended for routine laboratory use. PMID:23363840

  15. Isolation and characterization of Aeromonas from seafoods in Taipei.

    PubMed

    Yaun, S S; Lin, L P

    1993-05-01

    A total of 124 fresh seafoods and 158 processed seafoods collected from the retail markets and supermarkets in Taipei were tested for the contamination with motile Aeromonas spp. Of the fresh seafoods analyzed, 88% displayed the presence of Aeromonas. The isolation rates of various samples were as follows: 100%, freshwater fish; 95%, seawater fish; 78%, fish fillets; 84%, shrimp and crab of the crustacea group; 83%, bivalve shellfish and 84%, non-bivalve shellfish of the mollusca group, and 100%, seaweed. Of the 158 processed seafoods, 11% were contaminated by Aeromonas. The isolation rates were as follows: 0%, canned, dried, or frozen fresh seafood; 18%, salted seafood; 30%, fish cake; 7% vacuum-packaged fish cakes; 14%, frozen seafood dumplings; 8%, cooked seafoods. One hundred and eighty-three Aeromonas strains isolated in this survey were characterized to species level and tested for their ability to produce beta-hemolysin. Ninety-eight percent (98%) of the A. hydrophila produced beta-hemolysin on 5% blood agar, 94% of the A. sobria and 33% of the A. caviae produced beta-hemolysin. Thus it is likely that fresh seafoods are potentially significant sources of the virulent Aeromonas species and may play an important role in the epidemiology of Aeromonas-associated gastroenteritis.

  16. Characterization of Aeromonas species isolated from an estuarine environment

    PubMed Central

    Evangelista-Barreto, Norma Suely; de Carvalho, Fatima Cristiane Teles; Vieira, Regine Helena S. dos Fernandes; dos Reis, Cristhiane Moura Falavina; Macrae, Andrew; Rodrigues, Dália dos Prazeres

    2010-01-01

    Thirty water samples were collected, at two week intervals, from the estuary of the River Cocó. The aim was to characterize the presence, distribution and types of Aeromonas spp, in the estuary of the River Cocó, Ceara, Brazil (03°46’28.83’’S e 38°26’36.52’’S). Aeromonas were identified in 19 (63%) samples analyzed by plating and CFU counts. Presence/absence tests were positive for 11 (37%) of the samples resulting in the detection of Aeromonas in a total of 23 (77%) of samples. CFU counts varied from < 10 to 1.4 x 104 CFU mL-1. From the isolated strains seven species of Aeromonas were identified: A. caviae (29/69), A. veronii bv. sobria (13/69), A. veronii bv. veronii (8/69), A. trota (6/69), A. media (5/69), A. sobria (4/69) and A. hydrophila and Aeromonas sp. (2/69). Of the 38 strains tested, 23 (60%) showed resistance to at least one of the eight antimicrobials. Multiple resistance to antibiotics was observed in A. caviae, A. media , A. sóbria and A. veronii bv. sobria. Aeromonas caviae showed the highest multiple resistance, being resistant to four antibiotics. The presence of those microorganisms may contribute to the occurrence of gastroenteritis, mainly in children, since they are considered opportunists. PMID:24031516

  17. Aeromonas hydrophila Sepsis Mimicking Vibrio vulnificus Infection.

    PubMed

    Park, Se Young; Nam, Hyun Min; Park, Kun; Park, Seok Don

    2011-09-01

    Aeromonas hydrophila is a facultatively anaerobic, asporogenous gram-negative rod that has often been regarded as an opportunistic pathogen in hosts with impairment of a local or general defense mechanism. A 68-year-old alcoholic woman presented with shock and gangrene on the right arm. At first, her clinical presentations were severe painful erythematous swelling that worsened within a few hours with development of gangrene, edema, and blisters. Bullous fluid and blood cultures yielded A. hydrophila. Histopathological findings of sections obtained from the vesicle revealed subepidermal vesicles; necrosis of the epidermis, papillary dermis, and subcutaneous fat; and massive hemorrhage in the subcutis. Despite all efforts to save the patient, she died 8 hours after admission. Clinical features of A. hydrophila sepsis resemble those of Vibrio vulnificus sepsis. Therefore, in addition to the case report, we compared the cultural, biochemical, and morphological differences between A. hydrophila and V. vulnificus for facilitation of early and accurate identification of the causative agent.

  18. Selective isolation of Yersinia pestis from plague-infected fleas

    PubMed Central

    Sarovich, Derek S.; Colman, Rebecca E.; Price, Erin P.; Chung, Wai Kwan; Lee, Judy; Schupp, James M.; Alexander, James; Keim, Paul; Wagner., David M.

    2010-01-01

    We evaluated Yersinia CIN agar for the isolation of Yersinia pestis from infected fleas. CIN media is effective for the differentiation of Y. pestis from flea commensal flora and is sufficiently inhibitory to other bacteria that typically outcompete Y. pestis after 48 hours of growth using less selective media. PMID:20385178

  19. Immune Response to Plasmid- and Chromosome-Encoded Yersinia Antigens,

    DTIC Science & Technology

    The immune response of humans and mice to temperature-specific, plasmid- or chromosome-encoded proteins of Yersinia pestis and Yersinia ... enterocolitica was investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting. Extracts from Y. pestis and Y. enterocolitica

  20. 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...

  1. Nucleotide sequences specific to Yersinia pestis and methods for the detection of Yersinia pestis

    DOEpatents

    McCready, Paula M.; Radnedge, Lyndsay; Andersen, Gary L.; Ott, Linda L.; Slezak, Thomas R.; Kuczmarski, Thomas A.; Motin, Vladinir L.

    2009-02-24

    Nucleotide sequences specific to Yersinia pestis that serve as markers or signatures for identification of this bacterium were identified. In addition, forward and reverse primers and hybridization probes derived from these nucleotide sequences that are used in nucleotide detection methods to detect the presence of the bacterium are disclosed.

  2. MONITORING THE EFFECTIVENESS OF UV DISINFECTION OF AEROMONAS SPP. USING SELECTIVE AND NON-SELECTIVE MEDIA

    EPA Science Inventory

    This research was initiated to determine the sensitivity of Aeromonas spp. to ultraviolet (UV) disinfection. Aeromonas hydrophila is a contaminant listed on the USEPA's 1998 CCL. Three different Aeromonas spp. (A. hydrophila, A. sobria and A. caviae) were tested using membrane fi...

  3. Biological characterization of Aeromonas spp. isolated from the environment.

    PubMed Central

    Rahim, Z.; Khan, S. I.; Chopra, A. K.

    2004-01-01

    Cytotoxic enterotoxin (Act) is a key virulence factor in the pathogenesis of infections caused by Aeromonas spp. The cytotoxic enterotoxin gene (act) was detected in 32 out of 69 environmental isolates of Aeromonas spp. by hybridization with the act gene probe. To evaluate the pathogenic potential of the act gene probe-positive isolates, 32 act gene probe-positive and 31 randomly selected act gene probe-negative isolates were tested for enterotoxicity in a suckling mice assay (SMA), for haemolytic activity on sheep blood agar plates, for the presence of CAMP-like factors, and for cytotoxicity in a Vero cell line. The act gene probe-positive isolates significantly differed from the toxin gene probe-negative ones with respect to enterotoxicity in the SMA (P=0.009) and haemolytic activity (P=0.005). The CAMP-haemolysin phenotype was significantly associated with the rabbit ileal loop assay (P= 0.08), Vero cell assay (P= 0.064), and haemolysin production under the microaerophilic conditions (P= 0.056) of the act gene probe-positive isolates of Aeromonas spp. These data indicated the role of Act in the pathogenesis of Aeromonas infections and that the enterotoxic potential of Aeromonas spp. could be assessed by simply performing a CAMP-haemolysin assay. PMID:15310164

  4. Aeromonas hydrophila Lateral Flagellar Gene Transcriptional Hierarchy

    PubMed Central

    Wilhelms, Markus; Gonzalez, Victor; Merino, Susana

    2013-01-01

    Aeromonas hydrophila AH-3 lateral flagella are not assembled when bacteria grow in liquid media; however, lateral flagellar genes are transcribed. Our results indicate that A. hydrophila lateral flagellar genes are transcribed at three levels (class I to III genes) and share some similarities with, but have many important differences from, genes of Vibrio parahaemolyticus. A. hydrophila lateral flagellum class I gene transcription is σ70 dependent, which is consistent with the fact that lateral flagellum is constitutively transcribed, in contrast to the characteristics of V. parahaemolyticus. The fact that multiple genes are included in class I highlights that lateral flagellar genes are less hierarchically transcribed than polar flagellum genes. The A. hydrophila lafK-fliEJL gene cluster (where the subscript L distinguishes genes for lateral flagella from those for polar flagella) is exclusively from class I and is in V. parahaemolyticus class I and II. Furthermore, the A. hydrophila flgAMNL cluster is not transcribed from the σ54/LafK-dependent promoter and does not contain class II genes. Here, we propose a gene transcriptional hierarchy for the A. hydrophila lateral flagella. PMID:23335410

  5. Tetrahymena: An Alternative Model Host for Evaluating Virulence of Aeromonas Strains

    PubMed Central

    Pang, Mao-Da; Lin, Xiao-Qin; Hu, Meng; Li, Jing; Lu, Cheng-Ping; Liu, Yong-Jie

    2012-01-01

    An easier assessment model would be helpful for high-throughput screening of Aeromonas virulence. The previous study indicated the potential of Tetrahymena as a permissive model to examine virulence of Aeromonas hydrophila. Here our aim was to assess virulence of Aeromonas spp. using two model hosts, a zebrafish assay and Tetrahymena-Aeromonas co-culture, and to examine whether data from the Tetrahymena thermophila model reflects infections in the well-established animal model. First, virulence of 39 Aeromonas strains was assessed by determining the 50% lethal dose (LD50) in zebrafish. LD50 values ranging from 1.3×102 to 3.0×107 indicated that these strains represent a high to moderate degree of virulence and could be useful to assess virulence in the Tetrahymena model. In Tetrahymena-Aeromonas co-culture, we evaluated the virulence of Aeromonas by detecting relative survival of Aeromonas and Tetrahymena. An Aeromonas isolate was considered virulent when its relative survival was greater than 60%, while the Aeromonas isolate was considered avirulent if its relative survival was below 40%. When relative survival of T. thermophila was lower than 40% after co-culture with an Aeromonas isolate, the bacterial strain was regarded as virulent. In contrast, the strain was classified as avirulent if relative survival of T. thermophila was greater than 50%. Encouragingly, data from the 39 Aeromonas strains showed good correlation in zebrafish and Tetrahymena-Aeromonas co-culture models. The results provide sufficient data to demonstrate that Tetrahymena can be a comparable alternative to zebrafish for determining the virulence of Aeromonas isolates. PMID:23145022

  6. Insights into the evolution of Yersinia pestis through whole-genome comparison with Yersinia pseudotuberculosis

    SciTech Connect

    Chain, Patrick S. G.; Carniel, E.; Larimer, Frank W; Lamerdin, Jane; Vergez, Lisa; Land, Miriam L; Motin, V. L.; Brubaker, R. R.; Fowler, J.; Hinnebusch, J.; Marceau, M.; Medigue, Claudine; Chenal-Francisque, V.; Souza, B.; Dacheux, D.; Elliott, J. M.; Derbise, A.; Hauser, Loren John; Garcia, Emilio

    2004-09-01

    Yersinia pestis, the causative agent of plague, is a highly uniform clone that diverged recently from the enteric pathogen Yersinia pseudotuberculosis. Despite their close genetic relationship, they differ radically in their pathogenicity and transmission. Here, we report the complete genomic sequence of Y. pseudotuberculosis IP32953 and its use for detailed genome comparisons with available Y. pestis sequences. Analyses of identified differences across a panel of Yersinia isolates from around the world reveal 32 Y. pestis chromosomal genes that, together with the two Y. pestis-specific plasmids, to our knowledge, represent the only new genetic material in Y. pestis acquired since the the divergence from Y. pseudotuberculosis. In contrast, 149 other pseudogenes (doubling the previous estimate) and 317 genes absent from Y. pestis were detected, indicating that as many as 13% of Y. pseudotuberculosis genes no longer function in Y. pestis. Extensive insertion sequence-mediated genome rearrangements and reductive evolution through massive gene loss, resulting in elimination and modification of preexisting gene expression pathways, appear to be more important than acquisition of genes in the evolution of Y. pestis. These results provide a sobering example of how a highly virulent epidemic clone can suddenly emerge from a less virulent, closely related progenitor.

  7. Insights into the genome evolution of Yersinia pestis through whole genome comparison with Yersinia pseudotuberculosis

    SciTech Connect

    Souza, B; Stoutland, P; Derbise, A; Georgescu, A; Elliott, J; Land, M; Marceau, M; Motin, V; Hinnebusch, J; Simonet, M; Medigue, C; Dacheux, D; Chenal-Francisque, V; Regala, W; Brubaker, R R; Carniel, E; Chain, P; Verguez, L; Fowler, J; Garcia, E; Lamerdin, J; Hauser, L; Larimer, F

    2004-01-24

    Yersinia pestis, the causative agent of plague, is a highly uniform clone that diverged recently from the enteric pathogen Yersinia pseudotuberculosis. Despite their close genetic relationship, they differ radically in their pathogenicity and transmission. Here we report the complete genomic sequence of Y. pseudotuberculosis IP32953 and its use for detailed genome comparisons to available Y. pestis sequences. Analyses of identified differences across a panel of Yersinia isolates from around the world reveals 32 Y. pestis chromosomal genes that, together with the two Y. pestis-specific plasmids, represent the only new genetic material in Y. pestis acquired since the divergence from Y. pseudotuberculosis. In contrast, 149 new pseudogenes (doubling the previous estimate) and 317 genes absent from Y. pestis were detected, indicating that as many as 13% of Y. pseudotuberculosis genes no longer function in Y. pestis. Extensive IS-mediated genome rearrangements and reductive evolution through massive gene loss, resulting in elimination and modification of pre-existing gene expression pathways appear to be more important than acquisition of new genes in the evolution of Y. pestis. These results provide a sobering example of how a highly virulent epidemic clone can suddenly emerge from a less virulent, closely related progenitor.

  8. Yersinia pestis--etiologic agent of plague.

    PubMed Central

    Perry, R D; Fetherston, J D

    1997-01-01

    Plague is a widespread zoonotic disease that is caused by Yersinia pestis and has had devastating effects on the human population throughout history. Disappearance of the disease is unlikely due to the wide range of mammalian hosts and their attendant fleas. The flea/rodent life cycle of Y. pestis, a gram-negative obligate pathogen, exposes it to very different environmental conditions and has resulted in some novel traits facilitating transmission and infection. Studies characterizing virulence determinants of Y. pestis have identified novel mechanisms for overcoming host defenses. Regulatory systems controlling the expression of some of these virulence factors have proven quite complex. These areas of research have provide new insights into the host-parasite relationship. This review will update our present understanding of the history, etiology, epidemiology, clinical aspects, and public health issues of plague. PMID:8993858

  9. An outbreak of Yersinia pseudotuberculosis infection.

    PubMed

    Tertti, R; Granfors, K; Lehtonen, O P; Mertsola, J; Mäkelä, A L; Välimäki, I; Hänninen, P; Toivanen, A

    1984-02-01

    Nineteen patients were involved in an outbreak of infection caused by Yersinia pseudotuberculosis serotype 3. No epidemics attributable to this microorganism have been previously reported; the most extensive known cluster of cases involved four children in one family and their pet dog. The key finding in the outbreak described in the present study was the bacteriologic identification of serotype 3 in stool specimens from patients with clinically typical yersiniosis. Twelve cases were identified by isolation of Y pseudotuberculosis from stool specimens. An ELISA permitted serological diagnosis of the remaining seven cases. The antibody response was unusually slow in some patients. A noteworthy feature of the outbreak was the high incidence of postinfection complications, which developed in 10 of 19 patients. In spite of active screening of the respective families and environments of the patients, no transmitting factor was found, and the precise source of the infection remains unknown.

  10. Oral Challenge with Aeromonas in Protein-Malnourished Mice

    DTIC Science & Technology

    1994-01-01

    precipitaion after boiling. SRBC. sheep diarrhoea (RITARD) model (25) have red blood cells (hmolysis): Yt. adrenal cell culture; CHO. Chinese hamster...did not seem to affect the susceptibility of mice to deficient substitute for colostrum was not available. Aeromonas spp. infection, but there may be

  11. Genome Sequence of Hypervirulent Aeromonas hydrophila Strain HZAUAH

    PubMed Central

    Teng, Lin; Deng, Limei; Dong, Xingxing; Wei, Shun; Li, Jinquan

    2017-01-01

    ABSTRACT Aeromonas hydrophila, a zoonotic bacterium found in an expansive range of aquatic ecosystems, has been reported to cause severe diseases in fish, amphibians, reptiles, and mammals, including humans. Herein, we report the draft genome of the hypervirulent A. hydrophila strain HZAUAH isolated from a crucian in China. PMID:28302770

  12. Ciprofloxacin-resistant Aeromonas hydrophila cellulitis following leech therapy.

    PubMed

    Giltner, Carmen L; Bobenchik, April M; Uslan, Daniel Z; Deville, Jaime G; Humphries, Romney M

    2013-04-01

    We report a case of surgical site infection with ciprofloxacin-resistant Aeromonas hydrophila following leech therapy. Antimicrobial and genetic analyses of leech and patient isolates demonstrated that the resistant isolates originated from the leech gut microbiota. These data suggest that ciprofloxacin monotherapy as a prophylaxis regimen prior to leech therapy may not be effective in preventing infection.

  13. SENSITIVITY OF DIFFERENT AEROMONAS SPECIES TO COPPER AND SILVER

    EPA Science Inventory

    Aeromonas bacteria are common flora in surface and ground waters and are considered to be human pathogens. They can also be found in municipally treated drinking water, likely as a component of biofilms, as found in distribution system pipes and point of use water filters. It ...

  14. Ciprofloxacin-Resistant Aeromonas hydrophila Cellulitis following Leech Therapy

    PubMed Central

    Giltner, Carmen L.; Bobenchik, April M.; Uslan, Daniel Z.; Deville, Jaime G.

    2013-01-01

    We report a case of surgical site infection with ciprofloxacin-resistant Aeromonas hydrophila following leech therapy. Antimicrobial and genetic analyses of leech and patient isolates demonstrated that the resistant isolates originated from the leech gut microbiota. These data suggest that ciprofloxacin monotherapy as a prophylaxis regimen prior to leech therapy may not be effective in preventing infection. PMID:23363826

  15. YAPI, a New Yersinia pseudotuberculosis Pathogenicity Island

    PubMed Central

    Collyn, François; Billault, Alain; Mullet, Chantal; Simonet, Michel; Marceau, Michaël

    2004-01-01

    Pathogenicity islands (PAIs) are chromosomal clusters of pathogen-specific virulence genes often found at tRNA loci. In the Yersinia pseudotuberculosis 32777 chromosome, we characterized a 98-kb segment that has all of the characteristic features of a PAI, including insertion in a (phenylalanine) tRNA gene, the presence of a bacteriophage-like integrase-encoding gene, and direct repeats at the integration sites. The G+C content of the segment ranges from 31 to 60%, reflecting a genetic mosaic: this is consistent with the notion that the sequences were horizontally acquired. The PAI, termed YAPI (for Yersinia adhesion pathogenicity island), carries 95 open reading frames and includes (i) the previously described pil operon, encoding a type IV pilus that contributes to pathogenicity (F. Collyn et al., Infect. Immun. 70:6196-6205, 2002); (ii) a block of genes potentially involved in general metabolism; (iii) a gene cluster for a restriction-modification system; and (iv) a large number of mobile genetic elements. Furthermore, the PAI can excise itself from the chromosome at low frequency and in a precise manner, and deletion does not result in a significant decrease of bacterial virulence compared to inactivation of the fimbrial gene cluster alone. The prevalence and size of the PAI vary from one Y. pseudotuberculosis strain to another, and it can be found integrated into either of the two phe tRNA loci present on the species' chromosome. YAPI was not detected in the genome of the genetically closely related species Y. pestis, whereas a homologous PAI is harbored by the Y. enterocolitica chromosome. PMID:15271940

  16. Expression profiling reveals Spot 42 small RNA as a key regulator in the central metabolism of Aliivibrio salmonicida

    PubMed Central

    2012-01-01

    Background Spot 42 was discovered in Escherichia coli nearly 40 years ago as an abundant, small and unstable RNA. Its biological role has remained obscure until recently, and is today implicated in having broader roles in the central and secondary metabolism. Spot 42 is encoded by the spf gene. The gene is ubiquitous in the Vibrionaceae family of gamma-proteobacteria. One member of this family, Aliivibrio salmonicida, causes cold-water vibriosis in farmed Atlantic salmon. Its genome encodes Spot 42 with 84% identity to E. coli Spot 42. Results We generated a A. salmonicida spf deletion mutant. We then used microarray and Northern blot analyses to monitor global effects on the transcriptome in order to provide insights into the biological roles of Spot 42 in this bacterium. In the presence of glucose, we found a surprisingly large number of ≥ 2X differentially expressed genes, and several major cellular processes were affected. A gene encoding a pirin-like protein showed an on/off expression pattern in the presence/absence of Spot 42, which suggests that Spot 42 plays a key regulatory role in the central metabolism by regulating the switch between fermentation and respiration. Interestingly, we discovered an sRNA named VSsrna24, which is encoded immediately downstream of spf. This new sRNA has an expression pattern opposite to that of Spot 42, and its expression is repressed by glucose. Conclusions We hypothesize that Spot 42 plays a key role in the central metabolism, in part by regulating the pyruvat dehydrogenase enzyme complex via pirin. PMID:22272603

  17. Yersinia type III effectors perturb host innate immune responses

    PubMed Central

    Pha, Khavong; Navarro, Lorena

    2016-01-01

    The innate immune system is the first line of defense against invading pathogens. Innate immune cells recognize molecular patterns from the pathogen and mount a response to resolve the infection. The production of proinflammatory cytokines and reactive oxygen species, phagocytosis, and induced programmed cell death are processes initiated by innate immune cells in order to combat invading pathogens. However, pathogens have evolved various virulence mechanisms to subvert these responses. One strategy utilized by Gram-negative bacterial pathogens is the deployment of a complex machine termed the type III secretion system (T3SS). The T3SS is composed of a syringe-like needle structure and the effector proteins that are injected directly into a target host cell to disrupt a cellular response. The three human pathogenic Yersinia spp. (Y. pestis, Y. enterocolitica, and Y. pseudotuberculosis) are Gram-negative bacteria that share in common a 70 kb virulence plasmid which encodes the T3SS. Translocation of the Yersinia effector proteins (YopE, YopH, YopT, YopM, YpkA/YopO, and YopP/J) into the target host cell results in disruption of the actin cytoskeleton to inhibit phagocytosis, downregulation of proinflammatory cytokine/chemokine production, and induction of cellular apoptosis of the target cell. Over the past 25 years, studies on the Yersinia effector proteins have unveiled tremendous knowledge of how the effectors enhance Yersinia virulence. Recently, the long awaited crystal structure of YpkA has been solved providing further insights into the activation of the YpkA kinase domain. Multisite autophosphorylation by YpkA to activate its kinase domain was also shown and postulated to serve as a mechanism to bypass regulation by host phosphatases. In addition, novel Yersinia effector protein targets, such as caspase-1, and signaling pathways including activation of the inflammasome were identified. In this review, we summarize the recent discoveries made on Yersinia

  18. Yersinia pestis Yop Secretion Portein F: Purification, Characterization, and Protective Efficacy Against Bubonic Plague

    DTIC Science & Technology

    2005-03-17

    enterocolitica, Yersinia enterocolitica ; Y. pestis, Yersinia pestis.CA), and used for a recombination reaction with the pDONR201 entry vector (Invitrogen, CA...158 (2002) 401–408. [15] E. Hoiczyk, G. Bloebel, Polymerization of a single protein of the pathogen Yersinia enterocolitica into needles punctures

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

    PubMed Central

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

    2004-01-01

    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

  20. Rapid identification and typing of Yersinia pestis and other Yersinia species by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry

    PubMed Central

    2010-01-01

    Background Accurate identification is necessary to discriminate harmless environmental Yersinia species from the food-borne pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis and from the group A bioterrorism plague agent Yersinia pestis. In order to circumvent the limitations of current phenotypic and PCR-based identification methods, we aimed to assess the usefulness of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) protein profiling for accurate and rapid identification of Yersinia species. As a first step, we built a database of 39 different Yersinia strains representing 12 different Yersinia species, including 13 Y. pestis isolates representative of the Antiqua, Medievalis and Orientalis biotypes. The organisms were deposited on the MALDI-TOF plate after appropriate ethanol-based inactivation, and a protein profile was obtained within 6 minutes for each of the Yersinia species. Results When compared with a 3,025-profile database, every Yersinia species yielded a unique protein profile and was unambiguously identified. In the second step of analysis, environmental and clinical isolates of Y. pestis (n = 2) and Y. enterocolitica (n = 11) were compared to the database and correctly identified. In particular, Y. pestis was unambiguously identified at the species level, and MALDI-TOF was able to successfully differentiate the three biotypes. Conclusion These data indicate that MALDI-TOF can be used as a rapid and accurate first-line method for the identification of Yersinia isolates. PMID:21073689

  1. [Incidence, behavior and control of Aeromonas hydrophila in meat and dairy products].

    PubMed

    García-López, M L; Otero, A; García-Fernández, M C; Santos, J A

    1993-02-01

    This review deals with several aspects of Aeromonas hydrophila and other motile Aeromonas species associated with foodborne illness. Although it is mainly dedicated to the factors affecting growth and survival of this species in foods of animal origin, information on other topics is also provided. This paper includes sections on: Taxonomy, diseases caused by Aeromonas, virulence factors, reservoirs and prevalence in foods and water, factors affecting growth and survival, isolation and identification, and control measures.

  2. Yersinia ruckeri sp. nov., the redmouth (RM) bacterium

    USGS Publications Warehouse

    Ewing, W.H.; Ross, A.J.; Brenner, Don J.; Fanning, G. R.

    1978-01-01

    Cultures of the redmouth (RM) bacterium, one of the etiological agents of redmouth disease in rainbow trout (Salmo gairdneri) and certain other fishes, were characterized by means of their biochemical reactions, by deoxyribonucleic acid (DNA) hybridization, and by determination of guanine-plus-cytosine (G+C) ratios in DNA. The DNA relatedness studies confirmed the fact that the RM bacteria are members of the family Enterobacteriaceae and that they comprise a single species that is not closely related to any other species of Enterobacteriaceae. They are about 30% related to species of both Serratia and Yersinia. A comparison of the biochemical reactions of RM bacteria and serratiae indicated that there are many differences between these organisms and that biochemically the RM bacteria are most closely related to yersiniae. The G+C ratios of RM bacteria were approximated to be between 47.5 and 48.5% These values are similar to those of yersiniae but markedly different from those of serratiae. On the basis of their biochemical reactions and their G+C ratios, the RM bacteria are considered to be a new species of Yersinia, for which the name Yersinia ruckeri is proposed. Strain 2396-61 (= ATCC 29473) is designated the type strain of the species.

  3. Factors promoting acute and chronic diseases caused by yersiniae.

    PubMed Central

    Brubaker, R R

    1991-01-01

    The experimental system constructed with the medically significant yersiniae provides a powerful basic model for comparative study of factors required for expression of acute versus chronic disease. The system exploits the close genetic similarity between Yersinia pestis, the etiological agent of bubonic plague, and enteropathogenic Yersinia pseudotuberculosis and Yersinia enterocolitica. Y. pestis possesses three plasmids, of which one, shared by the enteropathogenic species, mediates a number of virulence factors that directly or indirectly promote survival within macrophages and immunosuppression. The two remaining plasmids are unique and encode functions that promote acute disease by enhancing bacterial dissemination in tissues and resistance to phagocytosis by neutrophils and monocytes. These properties are replaced in the enteropathogenic yersiniae by host cell invasins and an adhesin which promote chronic disease; the latter are cryptic in Y. pestis. Additional distinctions include specific mutational losses in Y. pestis which result in loss of fitness in natural environments plus gain of properties that facilitate transmission and infection via fleabite. Images PMID:1889045

  4. Snake-to-human transmission of Aeromonas (Pl) shigelloides resulting in gastroenteritis.

    PubMed

    Davis, W A; Chretien, J H; Garagusi, V F; Goldstein, M A

    1978-04-01

    A healthy young man developed acute gastroenteritis after handling an infected bao constrictor. The animal died after contracting "mouth-rot disease", a progressive ulcerative stomatitis of snakes charactistically caused a Aeromonas species. Stool cultures from the patient yielded a heavy growth of Aeromonas (Plesiomonas) shigelloides but no other enteric pathogens. Treatment wit sulfamethoxazole-trimethoprim resulted in rapid relief of clinical symptoms. Aeromonas species are not considered part of the normal human fecal flora and gastroenteritis due to this organism is rare. Furthermore, this case appears to represent a new zoonosis: human Aeromonas (Plasiomonas) gastroenteritis derived from contact with an infected animal host.

  5. LitR Is a Repressor of syp Genes and Has a Temperature-Sensitive Regulatory Effect on Biofilm Formation and Colony Morphology in Vibrio (Aliivibrio) salmonicida

    PubMed Central

    Bjelland, Ane Mohn; Ronessen, Maria; Robertsen, Espen; Willassen, Nils Peder

    2014-01-01

    Vibrio (Aliivibrio) salmonicida is the etiological agent of cold water vibriosis, a disease in farmed Atlantic salmon (Salmo salar) that is kept under control due to an effective vaccine. A seawater temperature below 12°C is normally required for disease development. Quorum sensing (QS) is a cell density-regulated communication system that bacteria use to coordinate activities involved in colonization and pathogenesis, and we have previously shown that inactivation of the QS master regulator LitR attenuates the V. salmonicida strain LFI1238 in a fish model. We show here that strain LFI1238 and a panel of naturally occurring V. salmonicida strains are poor biofilm producers. Inactivation of litR in the LFI1238 strain enhances medium- and temperature-dependent adhesion, rugose colony morphology, and biofilm formation. Chemical treatment and electron microscopy of the biofilm identified an extracellular matrix consisting mainly of a fibrous network, proteins, and polysaccharides. Further, by microarray analysis of planktonic and biofilm cells, we identified a number of genes regulated by LitR and, among these, were homologues of the Vibrio fischeri symbiosis polysaccharide (syp) genes. The syp genes were regulated by LitR in both planktonic and biofilm lifestyle analyses. Disruption of syp genes in the V. salmonicida ΔlitR mutant alleviated adhesion, rugose colony morphology, and biofilm formation. Hence, LitR is a repressor of syp transcription that is necessary for expression of the phenotypes examined. The regulatory effect of LitR on colony morphology and biofilm formation is temperature sensitive and weak or absent at temperatures above the bacterium's upper threshold for pathogenicity. PMID:24973072

  6. [Taxonomic characteristics and physiological properties of microorganisms from the gut of pike (Esox lucius)].

    PubMed

    Izveskova, G I; Nemtseva, N V; Plotnikov, A O

    2008-01-01

    The taxonomic composition and distribution of microorganisms differing in the degree of association with the intestinal mucosa of the pike (Lucius lucius) has been studied. Microorgansism of the families Enterobacteriaceae, Aeromonadaceae, and Vibrionaceae dominate in the gut microflora. Numerically prevailing bacterial species are characterized by high proteolytic and amylolytic enzyme activities as well as by high persistence accounted for by antilysozyme and antihistone activities. The results of this study show that Hafnia alvei, Yersinia ruckeri, Vibrio vulnificus, V. furnissii, Aeromonas salmonicida, and Shewanella putrefaciens may be regarded as normal components of the pike gut microflora.

  7. Comparative Genomic Hybridization Analysis of Yersinia enterocolitica and Yersinia pseudotuberculosis Identifies Genetic Traits to Elucidate Their Different Ecologies

    PubMed Central

    Jaakkola, Kaisa; Somervuo, Panu; Korkeala, Hannu

    2015-01-01

    Enteropathogenic Yersinia enterocolitica and Yersinia pseudotuberculosis are both etiological agents for intestinal infection known as yersiniosis, but their epidemiology and ecology bear many differences. Swine are the only known reservoir for Y. enterocolitica 4/O:3 strains, which are the most common cause of human disease, while Y. pseudotuberculosis has been isolated from a variety of sources, including vegetables and wild animals. Infections caused by Y. enterocolitica mainly originate from swine, but fresh produce has been the source for widespread Y. pseudotuberculosis outbreaks within recent decades. A comparative genomic hybridization analysis with a DNA microarray based on three Yersinia enterocolitica and four Yersinia pseudotuberculosis genomes was conducted to shed light on the genomic differences between enteropathogenic Yersinia. The hybridization results identified Y. pseudotuberculosis strains to carry operons linked with the uptake and utilization of substances not found in living animal tissues but present in soil, plants, and rotting flesh. Y. pseudotuberculosis also harbors a selection of type VI secretion systems targeting other bacteria and eukaryotic cells. These genetic traits are not found in Y. enterocolitica, and it appears that while Y. pseudotuberculosis has many tools beneficial for survival in varied environments, the Y. enterocolitica genome is more streamlined and adapted to their preferred animal reservoir. PMID:26605338

  8. Comparative Genomic Hybridization Analysis of Yersinia enterocolitica and Yersinia pseudotuberculosis Identifies Genetic Traits to Elucidate Their Different Ecologies.

    PubMed

    Jaakkola, Kaisa; Somervuo, Panu; Korkeala, Hannu

    2015-01-01

    Enteropathogenic Yersinia enterocolitica and Yersinia pseudotuberculosis are both etiological agents for intestinal infection known as yersiniosis, but their epidemiology and ecology bear many differences. Swine are the only known reservoir for Y. enterocolitica 4/O:3 strains, which are the most common cause of human disease, while Y. pseudotuberculosis has been isolated from a variety of sources, including vegetables and wild animals. Infections caused by Y. enterocolitica mainly originate from swine, but fresh produce has been the source for widespread Y. pseudotuberculosis outbreaks within recent decades. A comparative genomic hybridization analysis with a DNA microarray based on three Yersinia enterocolitica and four Yersinia pseudotuberculosis genomes was conducted to shed light on the genomic differences between enteropathogenic Yersinia. The hybridization results identified Y. pseudotuberculosis strains to carry operons linked with the uptake and utilization of substances not found in living animal tissues but present in soil, plants, and rotting flesh. Y. pseudotuberculosis also harbors a selection of type VI secretion systems targeting other bacteria and eukaryotic cells. These genetic traits are not found in Y. enterocolitica, and it appears that while Y. pseudotuberculosis has many tools beneficial for survival in varied environments, the Y. enterocolitica genome is more streamlined and adapted to their preferred animal reservoir.

  9. Real-time multiplex PCR assay for detection of Yersinia pestis and Yersinia pseudotuberculosis.

    PubMed

    Matero, Pirjo; Pasanen, Tanja; Laukkanen, Riikka; Tissari, Päivi; Tarkka, Eveliina; Vaara, Martti; Skurnik, Mikael

    2009-01-01

    A multiplex real-time polymerase chain reaction (PCR) assay was developed for the detection of Yersinia pestis and Yersinia pseudotuberculosis. The assay includes four primer pairs, two of which are specific for Y. pestis, one for Y. pestis and Y. pseudotuberculosis and one for bacteriophage lambda; the latter was used as an internal amplification control. The Y. pestis-specific target genes in the assay were ypo2088, a gene coding for a putative methyltransferase, and the pla gene coding for the plasminogen activator. In addition, the wzz gene was used as a target to specifically identify both Y. pestis and the closely related Y. pseudotuberculosis group. The primer and probe sets described for the different genes can be used either in single or in multiplex PCR assays because the individual probes were designed with different fluorochromes. The assays were found to be both sensitive and specific; the lower limit of the detection was 10-100 fg of extracted Y. pestis or Y. pseudotuberculosis total DNA. The sensitivity of the tetraplex assay was determined to be 1 cfu for the ypo2088 and pla probe labelled with FAM and JOE fluorescent dyes, respectively.

  10. virF-Positive Yersinia pseudotuberculosis and Yersinia enterocolitica Found in Migratory Birds in Sweden†

    PubMed Central

    Niskanen, Taina; Waldenström, Jonas; Fredriksson-Ahomaa, Maria; Olsen, Björn; Korkeala, Hannu

    2003-01-01

    During spring and autumn migrations, 468 fecal samples from 57 different species of migratory birds were collected in Sweden. In total, Yersinia spp. were isolated from 12.8% of collected samples. The most commonly found species was Yersinia enterocolitica, which was isolated from 5.6% of all collected samples, followed by Y. intermedia (3.8%), Y. frederiksenii (3.0%), Y. kristensenii (0.9%), Y. pseudotuberculosis (0.6%), and Y. rohdei (0.4%). The pathogenic, virF-positive Y. pseudotuberculosis strains were recovered from three thrushes. These strains belonged to the same bioserotype, 1/O:2, but had two different profiles as determined by pulsed-field gel electrophoresis with NotI and SpeI enzymes. In addition, 10 Y. enterocolitica strains, all from barnacle geese, belonged to bioserotype 3/O:3, which is associated with human disease. Two of the strains were pathogenic, carrying the virF gene on their plasmids. All pathogenic Y. pseudotuberculosis and Y. enterocolitica strains were recovered during the spring, and as the birds were caught during active migration they likely became infected at an earlier stage of the migration, thus potentially transporting these bacterial pathogens over long geographical distances. PMID:12902256

  11. Yersinia pestis, the cause of plague, is a recently emerged clone of Yersinia pseudotuberculosis.

    PubMed

    Achtman, M; Zurth, K; Morelli, G; Torrea, G; Guiyoule, A; Carniel, E

    1999-11-23

    Plague, one of the most devastating diseases of human history, is caused by Yersinia pestis. In this study, we analyzed the population genetic structure of Y. pestis and the two other pathogenic Yersinia species, Y. pseudotuberculosis and Y. enterocolitica. Fragments of five housekeeping genes and a gene involved in the synthesis of lipopolysaccharide were sequenced from 36 strains representing the global diversity of Y. pestis and from 12-13 strains from each of the other species. No sequence diversity was found in any Y. pestis gene, and these alleles were identical or nearly identical to alleles from Y. pseudotuberculosis. Thus, Y. pestis is a clone that evolved from Y. pseudotuberculosis 1,500-20,000 years ago, shortly before the first known pandemics of human plague. Three biovars (Antiqua, Medievalis, and Orientalis) have been distinguished by microbiologists within the Y. pestis clone. These biovars form distinct branches of a phylogenetic tree based on restriction fragment length polymorphisms of the locations of the IS100 insertion element. These data are consistent with previous inferences that Antiqua caused a plague pandemic in the sixth century, Medievalis caused the Black Death and subsequent epidemics during the second pandemic wave, and Orientalis caused the current plague pandemic.

  12. In vitro comparisons of the inhibitory activity of florfenicol copper sulfate and potassium permanganate towards Aeromonas hydrophila and Flavobacterium columnare

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila and Flavobacterium columnare, the etiological agents of motile aeromonas septicemia (MAS) and columnaris disease, respectively, have been recently causing crippling moralities to the sunshine bass, Morone chrysops female X Morone saxatilis male (Percichthyidae), industry in the ...

  13. Viscoelastic properties of an exopolysaccharide: Aeromonas gum, produced by Aeromonas nichidenii 5797.

    PubMed

    Xu, Xiaojuan; Chen, Pan; Zhang, Lina

    2007-01-01

    The viscoelastic properties of Aeromonas (A) gum in water were investigated by using the Rheometric Scientific ARES controlled strain rheometer. An intrinsic viscosity of 8336 ml/g was obtained according to the Fuoss-Straus equation. The effect of salt concentration on intrinsic viscosity revealed that the A gum exists as semiflexible chain. Typical shear-thinning (pseudoplastic) behavior was observed at concentrations higher than 0.52%. The zero shear viscosity (eta(0)) increased with increasing polysaccharide concentration (c) showing a gradient of approximately 1.0, 2.9 and 4.8 in different concentration domains. The critical concentrations c* and c**, at which the transitions from a dilute solution of independently moving chains to semidilute and then concentrated domains occurred, were determined roughly to be 1.2% and 3.5%. The results from dynamic experiments revealed that the A gum solution shows characteristics of polymer solutions without any evidence of gel-like character. All the results from steady and dynamic tests suggest that the A gum is a non-gelling polysaccharide. The temperature dependence of apparent viscosity was described by Arrhenius equation and the flow activation energy was estimated to be 45.2 kJ/mol, which is independent on polymer concentration.

  14. Aeromonas primary wound infection of a diver in polluted waters.

    PubMed Central

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

    1979-01-01

    Two separate species of Aeromonas, A. sobria (not listed as a species in Bergey's Manual of Determinative Bacteriology, 8th ed.) and A. hydrophila, were primary pathogens isolated from the leg wound of a diver conducting operations in polluted waters. This is the first recorded instance of a primary infection of soft tissue in a human caused by two species of Aeromonas, one of which was resistant to tetracycline. Because of the very rapid development of this wound infection, cytotoxicity of these organisms was examined in several biological systems. A. sobria was hemolytic for sheep erythrocytes, cytotoxic for Y-1 adrenal cells, and enterotoxic in rabbit ligated intestinal loops, whereas A. hydrophila was hemolytic and cytotoxic. Pertinent clinical, bacteriological, and environmental features of the case are presented. PMID:500794

  15. Plasmacytoid dendritic cells are crucial in Bifidobacterium adolescentis-mediated inhibition of Yersinia enterocolitica infection.

    PubMed

    Wittmann, Alexandra; Autenrieth, Ingo B; Frick, Julia-Stefanie

    2013-01-01

    In industrialized countries bacterial intestinal infections are commonly caused by enteropathogenic Enterobacteriaceae. The interaction of the microbiota with the host immune system determines the adequacy of an appropriate response against pathogens. In this study we addressed whether the probiotic Bifidobacterium adolescentis is protective during intestinal Yersinia enterocolitica infection. Female C57BL/6 mice were fed with B. adolescentis, infected with Yersinia enterocolitica, or B. adolescentis fed and subsequently infected with Yersinia enterocolitica. B. adolescentis fed and Yersinia infected mice were protected from Yersinia infection as indicated by a significantly reduced weight loss and splenic Yersinia load when compared to Yersinia infected mice. Moreover, protection from infection was associated with increased intestinal plasmacytoid dendritic cell and regulatory T-cell frequencies. Plasmacytoid dendritic cell function was investigated using depletion experiments by injecting B. adolescentis fed, Yersinia infected C57BL/6 mice with anti-mouse PDCA-1 antibody, to deplete plasmacytoid dendritic cells, or respective isotype control. The B. adolescentis-mediated protection from Yersinia dissemination to the spleen was abrogated after plasmacytoid dendritic cell depletion indicating a crucial function for pDC in control of intestinal Yersinia infection. We suggest that feeding of B. adolescentis modulates the intestinal immune system in terms of increased plasmacytoid dendritic cell and regulatory T-cell frequencies, which might account for the B. adolescentis-mediated protection from Yersinia enterocolitica infection.

  16. Yersinia pestis halotolerance illuminates plague reservoirs

    PubMed Central

    Malek, Maliya Alia; Bitam, Idir; Levasseur, Anthony; Terras, Jérôme; Gaudart, Jean; Azza, Said; Flaudrops, Christophe; Robert, Catherine; Raoult, Didier; Drancourt, Michel

    2017-01-01

    The plague agent Yersinia pestis persists for years in the soil. Two millennia after swiping over Europe and North Africa, plague established permanent foci in North Africa but not in neighboring Europe. Mapping human plague foci reported in North Africa for 70 years indicated a significant location at <3 kilometers from the Mediterranean seashore or the edge of salted lakes named chotts. In Algeria, culturing 352 environmental specimens naturally containing 0.5 to 70 g/L NaCl yielded one Y. pestis Orientalis biotype isolate in a 40 g/L NaCl chott soil specimen. Core genome SNP analysis placed this isolate within the Y. pestis branch 1, Orientalis biovar. Culturing Y. pestis in broth steadily enriched in NaCl indicated survival up to 150 g/L NaCl as L-form variants exhibiting a distinctive matrix assisted laser desorption-ionization time-of-flight mass spectrometry peptide profile. Further transcriptomic analyses found the upregulation of several outer-membrane proteins including TolC efflux pump and OmpF porin implied in osmotic pressure regulation. Salt tolerance of Y. pestis L-form may play a role in the maintenance of natural plague foci in North Africa and beyond, as these geographical correlations could be extended to 31 plague foci in the northern hemisphere (from 15°N to 50°N). PMID:28054667

  17. The pathogenicity of Yersinia enterocolitica for piglets.

    PubMed Central

    Schiemann, D A

    1988-01-01

    The pathogenicity of Yersinia enterocolitica, a bacterium that has been isolated frequently from healthy swine, was studied in piglets by oral challenge of two litters, one derived by cesarean section and deprived of colostrum, and the other delivered at full-term. Eight cesarean-derived piglets were divided into groups of two and challenged with four serotypes of Y. enterocolitica (O:8, O:21, O:3, O:13). Two deaths occurred and two piglets were killed because of severe illness before termination of the experiment eight days after challenge. Surviving piglets showed no clinical signs of illness. Rectal cultures were consistently positive and all cesarean-derived piglets were colonized in the small intestine and throat at necropsy. Full-term piglets were allowed access for 36 hours to sow colostrum containing low levels of antibody against the challenge strains. Six full-term piglets challenged with three serotypes of Y. enterocolitica (O:8, O:21, O:13) survived for 15 days without any signs of illness. These piglets had fewer positive rectal cultures and showed less extensive colonization of internal organs at necropsy than did cesarean-derived piglets. It is uncertain whether this increased resistance to infection with Y. enterocolitica resulted from colostrum-derived antibody, intestinal colonization with other bacteria, or an improved physical condition which accompanied full-term development. Nevertheless, the results of this challenge experiment suggest that piglets are capable of restricting colonization by Y. enterocolitica to the throat and intestinal tract without development of serious illness. PMID:3167717

  18. Electrotransformation of Yersinia ruckeri by plasmid DNA.

    PubMed

    Cutrín, J M; Conchas, R F; Barja, J L; Toranzo, A E

    1994-01-01

    Yersinia ruckeri, a fish pathogenic bacterium in aquaculture, was used to evaluate the electroporation as a new transformation method for this species. DNA used for the electrotransformation were plasmids of molecular mass ranging from 2.3 kb to 33 kb, and diverse replicons. To optimize this method we used Y. ruckeri 11.29 strain (from serotype 02) and pSU2718 DNA. The best transformation efficiency (6.0 x 10(5) transformants/micrograms DNA) was obtained with 12.5 kV/cm, 25 microF, 400 omega and 2 hours of incubation after pulse. When these conditions were applied to other strains belonging to different serotypes and other plasmids, we obtained transformants in all strains assayed, but only when using low molecular weight plasmids. Plasmid vectors and resident plasmid were not modified in host strains after electrotransformation. In studies of conformation we confirmed that only circular DNA was able for transformation. The utilization of this technique for direct cloning in Y. ruckeri makes possible further studies on recombinant DNA.

  19. Genome and Evolution of Yersinia pestis.

    PubMed

    Cui, Yujun; Song, Yajun

    2016-01-01

    This chapter summarizes researches on genome and evolution features of Yersinia pestis, the young pathogen that evolved from Y. pseudotuberculosis at least 5000 years ago. Y. pestis is a highly clonal bacterial species with closed pan-genome. Comparative genomic analysis revealed that genome of Y. pestis experienced highly frequent rearrangement and genome decay events during the evolution. The genealogy of Y. pestis includes five major branches, and four of them seemed raised from a "big bang" node that is associated with the Black Death. Although whole genome-wide variation of Y. pestis reflected a neutral evolutionary process, the branch length in the genealogical tree revealed over dispersion, which was supposedly caused by varied historical molecular clock that is associated with demographical effect by alternate cycles of enzootic disease and epizootic disease in sylvatic plague foci. In recent years, palaeomicrobiology researches on victims of the Black Death, and Justinian's plague verified that two historical pandemics were indeed caused by Y. pestis, but the etiological lineages might be extinct today.

  20. [Yersinia pestis and plague - an update].

    PubMed

    Stock, Ingo

    2014-12-01

    The plague of man is a severe, systemic bacterial infectious disease. Without antibacterial therapy, the disease is associated with a high case fatality rate, ranging from 40% (bubonic plague) to nearly 100% (septicemic and pneumonic plague). The disease is caused by Yersinia pestis, a non-motile, gram-negative, facultative anaerobic bacterium belonging to the family of Enterobacteriaceae. In nature, Y. pestis has been found in several rodent species and some other small animals such as shrews. Within its reservoir host, Y. pestis circulates via flea bites. Transmission of Y. pestis to humans occurs by the bite of rat fleas, other flea vectors or by non vectorial routes, e. g., handling infected animals or consumption of contaminated food. Human-to-human transmission of the pathogen occurs primarily through aerosol droplets. Compared to the days when plague was a pandemic scourge, the disease is now relatively rare and limited to some rural areas of Africa. During the last ten years, however, plague outbreaks have been registered repea- tedly in some African regions. For treatment of plague, streptomycin is still considered the drug of choice. Chloramphenicol, doxycycline, gentamicin and ciprofloxacin are also promising drugs. Recombinant vaccines against plague are in clinical development.

  1. Genetically manipulated virulence of Yersinia enterocolitica.

    PubMed Central

    Heesemann, J; Algermissen, B; Laufs, R

    1984-01-01

    Mobilizable virulence plasmids of Yersinia enterocolitica of serotypes O:3 and O:9 were constructed by cointegration of a mobilizable vector into the virulence plasmids. The obtained cointegrates were mobilized into plasmidless Y. enterocolitica strains of serotypes O:3, O:5, O:8, and O:9. The transfer experiments revealed the existence of two different subgroups of plasmid-associated traits. (i) Animal virulence functions (mouse lethality and conjuctivitis provocation) were only transferable to plasmid-cured derivatives of virulent parent strains (serotypes O:3, O:8, and O:9), but they were not transferable to Y. enterocolitica antigen reference strains (serotypes O:3 and O:8) or to a plasmidless clinical isolate of serotype O:5. A further striking result was that a serotype O:8 strain regained the mouse lethality trait after receipt of a plasmid from a strain not lethal to mice. These results demonstrate that plasmid-mediated animal virulence functions are not uniformly expressed within Y. enterocolitica. (ii) The second subgroup of plasmid-mediated traits (calcium dependency, surface agglutinogens, HEp-2 cell adherence, and protein release) were transferable to all Y. enterocolitica recipient strains tested (serotypes O:3, O:5, O:8, and O:9 of different origin). For the first time HEp-2 cell adherence and temperature-induced release of five major protein species are described as transferable traits. Images PMID:6480101

  2. Clinical and biochemical significance of toxin production by Aeromonas hydrophila.

    PubMed

    Kindschuh, M; Pickering, L K; Cleary, T G; Ruiz-Palacios, G

    1987-05-01

    Production of cytotoxin and enterotoxin by Aeromonas strains obtained from stools of 50 children in Mexico and Texas and from blood of 9 children with sepsis was determined. Results were correlated with clinical features of infected children as well as with biochemical traits of Aeromonas strains. Cytotoxin was produced by 40 of 42 Aeromonas strains (95%) isolated from stools of children with diarrhea, by all 8 isolates from stools of well children, and by all 9 isolates from children with sepsis. There was no difference in the quantities (amount of cytotoxin per milligram of protein required to kill 50% of the cells) of cytotoxin produced and in clinical manifestations among the groups. None of the isolates produced a toxin that could be neutralized by antiserum raised against Shiga toxin produced by Shigella dysenteriae 1 60R. Heat-labile-like enterotoxin (LT) was produced by 26 of 42 stool isolates (62%), while only 1 of the 42 isolates (2%) produced enterotoxinlike activity in suckling mice; 65% of the cytotoxin-producing strains also produced an LT-like material. All strains from blood produced LT-like material, and 2 of 6 (33%) produced activity in suckling mice. All strains produced hemolysin; 37 of 57 (65%) were Voges-Proskauer positive; 27 of 57 (47%) were lysine decarboxylase positive by API 20E strips, none were positive for lysine decarboxylose production by lysin-iron agar slants at 24 h, but 17 of 54 (31%) were positive at 48 h. There was no correlation between biochemical reactions and enterotoxin or cytotoxin production. There appears to be no correlation between toxin production by Aeromonas spp. and gastroenteritis.

  3. Evolutionary Roots and Diversification of the Genus Aeromonas

    PubMed Central

    Sanglas, Ariadna; Albarral, Vicenta; Farfán, Maribel; Lorén, J. G.; Fusté, M. C.

    2017-01-01

    Despite the importance of diversification rates in the study of prokaryote evolution, they have not been quantitatively assessed for the majority of microorganism taxa. The investigation of evolutionary patterns in prokaryotes constitutes a challenge due to a very scarce fossil record, limited morphological differentiation and frequently complex taxonomic relationships, which make even species recognition difficult. Although the speciation models and speciation rates in eukaryotes have traditionally been established by analyzing the fossil record data, this is frequently incomplete, and not always available. More recently, several methods based on molecular sequence data have been developed to estimate speciation and extinction rates from phylogenies reconstructed from contemporary taxa. In this work, we determined the divergence time and temporal diversification of the genus Aeromonas by applying these methods widely used with eukaryotic taxa. Our analysis involved 150 Aeromonas strains using the concatenated sequences of two housekeeping genes (approximately 2,000 bp). Dating and diversification model analyses were performed using two different approaches: obtaining the consensus sequence from the concatenated sequences corresponding to all the strains belonging to the same species, or generating the species tree from multiple alignments of each gene. We used BEAST to perform a Bayesian analysis to estimate both the phylogeny and the divergence times. A global molecular clock cannot be assumed for any gene. From the chronograms obtained, we carried out a diversification analysis using several approaches. The results suggest that the genus Aeromonas began to diverge approximately 250 millions of years (Ma) ago. All methods used to determine Aeromonas diversification gave similar results, suggesting that the speciation process in this bacterial genus followed a rate-constant (Yule) diversification model, although there is a small probability that a slight

  4. Effects of cultural conditions on protease production by Aeromonas hydrophila.

    PubMed Central

    O'Reilly, T; Day, D F

    1983-01-01

    Production of extracellular proteolytic activity by Aeromonas hydrophila was influenced by temperature, pH, and aeration. Conditions which produced maximal growth also resulted in maximal protease production. Enzyme production appeared to be modulated by an inducer catabolite repression system whereby NH4+ and glucose repressed enzyme production and complex nitrogen and nonglucose, carbon energy sources promoted it. Under nutritional stress, protease production was high, despite poor growth. PMID:6342534

  5. [Detection of Yersinia Enterocolitica Bacteriophage PhiYe-F10 Lysis Spectrum and Analysis of the Relationship between Lysis Ability and Virulence Gene of Yersinia Enterocolitica].

    PubMed

    Zha, Tao; Liang, Junrong; Xiao, Yuchun; Jing, Huaiqi

    2016-03-01

    To determine the lysis spectrum of Yersinia enterocolitica bacteriophage phiYe-F10 and to analyze the relationship between the lysis ability of phiYe-F10 and the virulence gene of Yersinia enterocolitica. To observe the lysis ability of the phage phiYe-F10 to the different Yersinia strains with the double-layer technique. The strains used in this study including 213 of Yersinia enterocolitica and 36 of Yersinia pseudotuberculosis and 1 of Yersinia pestis. The virulence genes of these Yersinia enterocolitica (attachment invasion locus (ail) and enterotoxin (ystA, ystB) and yersinia adhesin A (yadA), virulence factor (virF), specific gene for lipopolysaccharide O-side chain of serotype O : 3 (rfbc) were all detected. Among the 213 Yersinia enterocolitica, 84 strains were O : 3 serotype (78 strains with rfbc gene), 10 were serotype O : 5, 13 were serotype O : 8, 34 were serotype O : 9 and 72 were other serotypes. Of these, 77 were typical pathogenic Yersinia enterocolitica harboring with virulence plasmid (ail+, ystA+, ystB-, yadA+, virF+), and 15 were pathogenic bacterial strains deficiency virulence plasmid (ail+, ystA+, ystB-, yadA-, virF-) and the rest 121 were non pathogenic genotype strains. PhiYe-F10 lysed the 71 serotype O : 3 Yersinia enterocolitica strains which were all carried with rfbc+, including 52 pathogenic Yersinia enterocolitica, 19 nonpathogenic Y. enterocolitica. The phiYe-F10 can not lysed serotype O : 5, O : 9 and other serotype Y. enterocolitica, the lysis rate of serotype O : 3 was as high as 84.5%. The phiYe-F10 can not lysed Yersinia pseudotuberculosis and Yersinia pestis. Yersinia phage phiYe-F10 is highly specific for serotype O : 3 Yersinia enterocolitic at 25 degrees C, which showed a typical narrow lysis spectrum. Phage phiYe-F10 can lysed much more pathogenic Y. enterocolitica than nonpathogenic Y. enterocolitica.

  6. Detection of a Yersinia pestis gene homologue in rodent samples

    PubMed Central

    Greenwood, Alex D.; Tsangaras, Kyriakos; Giles, Tom C.; Barrow, Paul A.; Hannant, Duncan; Abu-Median, Abu-Bakr; Yon, Lisa

    2016-01-01

    A homologue to a widely used genetic marker, pla, for Yersinia pestis has been identified in tissue samples of two species of rat (Rattus rattus and Rattus norvegicus) and of mice (Mus musculus and Apodemus sylvaticus) using a microarray based platform to screen for zoonotic pathogens of interest. Samples were from urban locations in the UK (Liverpool) and Canada (Vancouver). The results indicate the presence of an unknown bacterium that shares a homologue for the pla gene of Yersinia pestis, so caution should be taken when using this gene as a diagnostic marker. PMID:27602258

  7. Evolutionary and Diagnostic Implications of Intragenomic Heterogeneity in the 16S rRNA Gene in Aeromonas Strains

    PubMed Central

    Morandi, Alessia; Zhaxybayeva, Olga; Gogarten, J. Peter; Graf, Joerg

    2005-01-01

    Sequencing 16S rRNA genes (SSU) cloned from Aeromonas strains revealed that strains contained up to six copies differing by ≤1.5%. The SSU copies from Aeromonas veronii LMG13695 clustered with sequences from four Aeromonas species. These results demonstrate intragenomic heterogeneity of SSU and suggest caution when using SSU to identify aeromonads. PMID:16159790

  8. Prevalence, characterization, and antimicrobial resistance of Yersinia species and Yersinia enterocolitica isolated from raw milk in farm bulk tanks.

    PubMed

    Jamali, Hossein; Paydar, Mohammadjavad; Radmehr, Behrad; Ismail, Salmah

    2015-02-01

    The aims of this study were to investigate the prevalence and to characterize and determine the antibiotic resistance of Yersinia spp. isolates from raw milk. From September 2008 to August 2010, 446 raw milk samples were obtained from farm bulk milk tanks in Varamin, Iran. Yersinia spp. were detected in 29 (6.5%) samples, out of which 23 (79.3%), 5 (17.2%), and 1 (3.4%) were isolated from cow, sheep, and goat raw milk, respectively. The most common species isolated was Yersinia enterocolitica (65.5%), followed by Yersinia frederiksenii (31%), and Yersinia kristensenii (3.4%). Of the 19 Y. enterocolitica isolates, 14 (73.7%) were grouped into bioserotype 1A/O:9, 4 (21.1%) belonged to bioserotype 1B:O8, 1 (5.3%) belonged to bioserotype 4/O:3, and 1 isolate (biotype 1A) was not typable. All the isolates of biotypes 1B and 4harbored both the ystA and ail genes. However, all the isolates of biotype 1A were only positive for the ystB gene. The tested Yersinia spp. showed the highest percentages of resistance to tetracycline (48.3%), followed by ciprofloxacin and cephalothin (each 17.2%), ampicillin (13.8%), streptomycin (6.9%), and amoxicillin and nalidixic acid (each 3.4%). All of the tested isolates demonstrated significant sensitivity to gentamicin and chloramphenicol. Recovery of potentially pathogenic Y. enterocolitica from raw milk indicates high risks of yersiniosis associated with consumption of raw milk.

  9. Effect of copper sulfate on Aeromonas hydrophila infection in channel catfish (Ictalurus punctatus) fingerlings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Motile Aeromonad Septicemia (MAS) results from primary or secondary infection with bacteria from Gram(-) Aeromonas spp., including Aeromonas hydrophila. Since 2009, an emerging strain of A. hydrophila has been associated, as a primary pathogen, with significant morbidity and mortality in the U.S. c...

  10. 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

  11. 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

  12. Classification of a hypervirulent Aeromonas hydrophila pathotype responsible for epidemic outbreaks in warm-water fishes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 P...

  13. Comparative genomics of Aeromonas hydrophila isolates from an epidemic in channel catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Aeromonas hydrophila was identified as the etiologic agent infecting farmed channel catfish in 2009/2010, resulting in higher mortality rates than typical for motile Aeromonas septicemia with over 5 million pounds of catfish lost to this outbreak. The biochemistry, molecular phylogeny, an...

  14. 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...

  15. Chitin degradation and utilization by virulent Aeromonas hydrophila strain ML10-51K

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virulent Aeromonas hydrophila (vAh) is one of the most important bacterial pathogens that causes persistent outbreaks of motile Aeromonas septicemia (MAS) in warm-water fishes. Among factors associated with MAS outbreaks, the survivability of this pathogen in aquatic environments is of great concern...

  16. Proteomic Characterization of Yersinia pestis Virulence

    SciTech Connect

    Chromy, B; Murphy, G; Gonzales, A; Fitch, J P; McCutchen-Maloney, S L

    2005-01-05

    Yersinia pestis, the etiological agent of plague, functions via the Type III secretion mechanism whereby virulence factors are induced upon interactions with a mammalian host. Here, the Y. pestis proteome was studied by two-dimensional differential gel electrophoresis (2-D DIGE) under physiologically relevant growth conditions mimicking the calcium concentrations and temperatures that the pathogen would encounter in the flea vector and upon interaction with the mammalian host. Over 4100 individual protein spots were detected of which hundreds were differentially expressed in the entire comparative experiment. A total of 43 proteins that were differentially expressed between the vector and host growth conditions were identified by mass spectrometry. Expected differences in expression were observed for several known virulence factors including catalase-peroxidase (KatY), murine toxin (Ymt), plasminogen activator (Pla), and F1 capsule antigen (Caf1), as well as putative virulence factors. Chaperone proteins and signaling molecules hypothesized to be involved in virulence due to their role in Type III secretion were also identified. Other differentially expressed proteins not previously reported to contribute to virulence are candidates for more detailed mechanistic studies, representing potential new virulence determinants. For example, several sugar metabolism proteins were differentially regulated in response to lower calcium and higher temperature, suggesting these proteins, while not directly connected to virulence, either represent a metabolic switch for survival in the host environment or may facilitate production of virulence factors. Results presented here contribute to a more thorough understanding of the virulence mechanism of Y. pestis through proteomic characterization of the pathogen under induced virulence.

  17. Green fluorescent protein labeling of food pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis.

    PubMed

    Gensberger, Eva Theres; Kostić, Tanja

    2017-01-01

    Labeling of bacteria with marker genes, such as green fluorescent protein, is a useful and practicable tool for tracking and enumerating bacterial cells in a complex environment e.g. discrimination from the indigenous background population. In this study, novel TurboGFP prokaryotic expression vector was utilized for labeling of Yersinia species. Y. enterocolitica biovar 1A, biovar 2, biovar 4 and Y. pseudotuberculosis were successfully transformed with the vector and expressed bright green fluorescence that was even detectable visually by eye. No adverse effects were observed in growth behavior of the labeled strains compared to wild type (parental) strains and vector maintenance for longer time periods could be achieved for Y. enterocolitica biovar 1A, Y. enterocolitica biovar 2 and Y. pseudotuberculosis.

  18. Regulation of flagellum biosynthesis within the fish pathogen Yersinia ruckeri

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yersinia ruckeri, a Gram negative Enterobacterium, is the causative agent of enteric red mouth disease (ERM) within farmed rainbow trout (Oncorhynchus mykiss, Walbaum). There has been an increase of ERM outbreaks in previously vaccinated trout caused by a recently emerged, non-motile variant of Y. r...

  19. Susceptibilities of Yersinia pestis strains to 12 antimicrobial agents.

    PubMed

    Wong, J D; Barash, J R; Sandfort, R F; Janda, J M

    2000-07-01

    Ninety-two strains of Yersinia pestis recovered over a 21-year period were evaluated for susceptibility to traditional and newer antimicrobial agents. In vitro resistance was noted only against rifampin and imipenem (approximately 20% of strains). The most active compounds (MIC at which 90% of the isolates tested are inhibited) against Y. pestis were cefixime, ceftriaxone, trimethoprim-sulfamethoxazole, and trovafloxacin.

  20. Mechanisms of Yersinia YopO kinase substrate specificity

    PubMed Central

    Lee, Wei Lin; Singaravelu, Pavithra; Wee, Sheena; Xue, Bo; Ang, Khay Chun; Gunaratne, Jayantha; Grimes, Jonathan M.; Swaminathan, Kunchithapadam; Robinson, Robert C.

    2017-01-01

    Yersinia bacteria cause a range of human diseases, including yersiniosis, Far East scarlet-like fever and the plague. Yersiniae modulate and evade host immune defences through injection of Yersinia outer proteins (Yops) into phagocytic cells. One of the Yops, YopO (also known as YpkA) obstructs phagocytosis through disrupting actin filament regulation processes - inhibiting polymerization-promoting signaling through sequestration of Rac/Rho family GTPases and by using monomeric actin as bait to recruit and phosphorylate host actin-regulating proteins. Here we set out to identify mechanisms of specificity in protein phosphorylation by YopO that would clarify its effects on cytoskeleton disruption. We report the MgADP structure of Yersinia enterocolitica YopO in complex with actin, which reveals its active site architecture. Using a proteome-wide kinase-interacting substrate screening (KISS) method, we identified that YopO phosphorylates a wide range of actin-modulating proteins and located their phosphorylation sites by mass spectrometry. Using artificial substrates we clarified YopO’s substrate length requirements and its phosphorylation consensus sequence. These findings provide fresh insight into the mechanism of the YopO kinase and demonstrate that YopO executes a specific strategy targeting actin-modulating proteins, across multiple functionalities, to compete for control of their native phospho-signaling, thus hampering the cytoskeletal processes required for macrophage phagocytosis. PMID:28051168

  1. Molecular cloning of cecropin B responsive endonucleases in Yersinia ruckeri

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have previously demonstrated that Yersinia ruckeri resists cecropin B in an inducible manner. In this study, we sought to identify the molecular changes responsible for the inducible cecropin B resistance of Y. ruckeri. Differences in gene expression associated with the inducible resistance were ...

  2. Aeromonas-Associated Diarrhea in Children Under 5 Years: The GEMS Experience.

    PubMed

    Qamar, Farah Naz; Nisar, Muhammad Imran; Quadri, Farheen; Shakoor, Sadia; Sow, Samba O; Nasrin, Dilruba; Blackwelder, William C; Wu, Yukun; Farag, Tamer; Panchalingham, Sandra; Sur, Dipika; Qureshi, Shahida; Faruque, Abu S G; Saha, Debasish; Alonso, Pedro L; Breiman, Robert F; Bassat, Quique; Tamboura, Boubou; Ramamurthy, Thandavarayan; Kanungo, Suman; Ahmed, Shahnawaz; Hossain, Anowar; Das, Sumon K; Antonio, Martin; Hossain, M Jahangir; Mandomando, Inacio; Tennant, Sharon M; Kotloff, Karen L; Levine, Myron M; Zaidi, Anita K M

    2016-10-05

    We report the clinical findings, epidemiology, and risk factors for moderate-to-severe diarrhea (MSD) associated with Aeromonas species in children 0-59 months of age, from the Global Enteric Multicenter Study, conducted at three sites in south Asia and four sites in sub-Saharan Africa. Children with MSD were enrolled along with controls matched for age, gender, and neighborhood. Pooled, age-stratified conditional logistic regression models were applied to evaluate the association of Aeromonas infection controlling for coinfecting pathogens and sociodemographic variables. A pooled, age-stratified, multivariate logistic regression analysis was done to identify risk factors associated with Aeromonas positivity in MSD cases. A total of 12,110 cases and 17,291 matched controls were enrolled over a period of 48 months. Aeromonas was identified as a significant pathogen in 736 cases of MSD in Pakistan and Bangladesh (22.2%). Aeromonas remained a significant pathogen even after adjustment for the presence of other pathogens and sociodemographic factors. Odds ratio (OR) for Aeromonas were higher in the presence of Shigella (matched OR: 6.2, 95% confidence interval [CI]: 1.9-20.2). Cases of Aeromonas were likely to present with dysentery, particularly in the 0-11 months (OR: 1.4, 95% CI 1.0-2.0) and 12-23 months (OR: 1.8, 95% CI: 1.3-2.5) age group. The odds of Aeromonas increased with increasing degree of stunting, being highest for severe stunting (OR: 10.1, 95% CI: 3.6-28.9). Aeromonas is a significant pathogen for MSD in Pakistan and Bangladesh. Presence of dysentery and co-occurrence with other pathogens, notably Shigella spp. are significant features of Aeromonas-associated diarrhea.

  3. Genotyping of human and porcine Yersinia enterocolitica, Yersinia intermedia, and Yersinia bercovieri strains from Switzerland by amplified fragment length polymorphism analysis.

    PubMed

    Boghenbor, Kathrin Kuehni; On, Stephen L W; Kokotovic, Branko; Baumgartner, Andreas; Wassenaar, Trudy M; Wittwer, Matthias; Bissig-Choisat, Beatrice; Frey, Joachim

    2006-06-01

    In this study, 231 strains of Yersinia enterocolitica, 25 strains of Y. intermedia, and 10 strains of Y. bercovieri from human and porcine sources (including reference strains) were analyzed using amplified fragment length polymorphism (AFLP), a whole-genome fingerprinting method for subtyping bacterial isolates. AFLP typing distinguished the different Yersinia species examined. Representatives of Y. enterocolitica biotypes 1A, 1B, 2, 3, and 4 belonged to biotype-related AFLP clusters and were clearly distinguished from each other. Y. enterocolitica biotypes 2, 3, and 4 appeared to be more closely related to each other (83% similarity) than to biotypes 1A (11%) and 1B (47%). Biotype 1A strains exhibited the greatest genetic heterogeneity of the biotypes studied. The biotype 1A genotypes were distributed among four major clusters, each containing strains from both human and porcine sources, confirming the zoonotic potential of this organism. The AFLP technique is a valuable genotypic method for identification and typing of Y. enterocolitica and other Yersinia spp.

  4. Seroprevalence of enteropathogenic Yersinia spp. in pig batches at slaughter.

    PubMed

    Vanantwerpen, Gerty; Van Damme, Inge; De Zutter, Lieven; Houf, Kurt

    2014-09-01

    Enteropathogenic Yersinia spp. are one of the main causes of foodborne bacterial infections in Europe. Slaughter pigs are the main reservoir and carcasses are contaminated during a sub-optimal hygienically slaughtering-process. Serology is potentially an easy option to test for the Yersinia-status of the pig (batches) before slaughter. A study of the variation in activity values (OD%) of Yersinia spp. in pigs and pig batches when applying a serological test were therefore conducted. In this study, pieces of the diaphragm of 7047 pigs, originating from 100 farms, were collected and meat juice was gathered, where after an enzyme-linked immunosorbent assay (ELISA) Pigtype Yopscreen (Labor Diagnostik Leipzig, Qiagen, Leipzig, Germany) was performed. The results were defined positive if the activity values exceeded the proposed cut-off value of 30 OD%. Results at pig level displayed a bimodal-shaped distribution with modes at 0-10% (n=879) and 50-60% (n=667). The average OD% was 51% and 66% of the animals tested positive. The within-batch seroprevalence ranged from 0 to 100% and also showed a bimodal distribution with modes at 0% (n=7) and 85-90% (n=16). On 7 farms, no single seropositive animal was present and in 22 farms, the mean OD% was below 30%. Based on the results obtained at slaughter, 66% of the pigs had contact with enteropathogenic Yersinia spp. at farm level. The latter occurred in at least 93% of the farms indicating that most farms are harboring enteropathogenic Yersinia spp.

  5. Radiation Resistance and Injury of Yersinia enterocolitica

    PubMed Central

    El-Zawahry, Yehia A.; Rowley, D. B.

    1979-01-01

    The D values of Yersinia enterocolitica strains IP134, IP107, and WA, irradiated at 25°C in Trypticase soy broth, ranged from 9.7 to 11.8 krad. When irradiated in ground beef at 25 and −30°C, the D value of strain IP107 was 19.5 and 38.8 krad, respectively. Cells suspended in Trypticase soy broth were more sensitive to storage at −20°C than those mixed in ground beef. The percentages of inactivation and of injury (inability to form colonies in the presence of 3.0% NaCl) of cells stored in ground beef for 10 days at −20°C were 70 and 23%, respectively. Prior irradiation did not alter the cell's sensitivity to storage at −20°C, nor did storage at −20°C alter the cell's resistance to irradiation at 25°C. Added NaCl concentrations of up to 4.0% in Trypticase soy agar (TSA) (which contains 0.5% NaCl) had little effect on colony formation at 36°C of unirradiated Y. enterocolitica. With added 4.0% NaCl, 79% of the cells formed colonies at 36°C; with 5.0% NaCl added, no colonies were formed. Although 2.5% NaCl added to ground beef did not sensitize Y. enterocolitica cells to irradiation, when added to TSA it reduced the number of apparent radiation survivors. Cells uninjured by irradiation formed colonies on TSA when incubated at either 36 or 5°C. More survivors of an exposure to 60 krad were capable of recovery and forming colonies on TSA when incubated at 36°C for 1 day than at 5°C for 14 days. This difference in count was considered a manifestation of injury to certain survivors of irradiation. PMID:570017

  6. Global Expression Studies of Yersinia Pestis Pathogenicity

    SciTech Connect

    Garcia, E; Motin, V; Brubaker, R; Fitch, P

    2002-10-15

    The aim of these studies continues to be the investigation into the molecular mechanisms that underlie the virulence process in Yersinia pestis. In particular, the focus of this work centers on the identification of novel genes and pathways responsible for the pathogenic properties of this organism. In spite of more than four decades of intense investigation in this field, the dilemma as to what makes Y. pestis such a virulent and lethal pathogen remains unanswered. The method being employed makes use microarray technology (DNA chip) that enables the examination of the global activities of the whole complement of genes in this pathogen. Two primary resources available to the investigators (one directly obtained from a separate CBNP-funded project) make these studies possible: (1) Whole genome comparisons of the genes in Y. pestis and its near neighbors with attenuated or non pathogenic characteristics, and (2) the ability to duplicate in vitro, conditions that mimic the infection process of this pathogen. This year we have extended our studies from the original work of characterizing the global transcriptional regulation in Y. pestis triggered during temperature transition from 26 C to 37 C (roughly conditions found in the flea vector and the mammalian host, respectively) to studies of regulation encountered during shift between growth from conditions of neutral pH to acidic pH (the latter conditions, those mimic the environment found inside macrophages, a likely environment found by these cells during infection.). For this work, DNA arrays containing some 5,000 genes (the entire genome of Y. pestis plus those genes found uniquely in the enteropathogen, and near neighbor, Y. pseudotuberculosis) are used to monitor the simultaneous expression levels of each gene of known and unknown function in Y. pestis. Those genes that are up-regulate under the experimental conditions represent genes potentially involved in the pathogenic process. The ultimate role in

  7. Multifocal Aeromonas Osteomyelitis in a Child with Leukemia

    PubMed Central

    Doganis, Dimitrios; Baka, Margarita; Tsolia, Maria; Pourtsidis, Apostolos; Lebessi, Evangelia; Varvoutsi, Maria; Bouhoutsou, Despina; Kosmidis, Helen

    2016-01-01

    Aeromonas hydrophila is a Gram negative organism causing both intestinal and extraintestinal disease. The case of a 14-year-old girl with underlying immunodeficiency and leukemia who developed systemic A. hydrophila infection is described in this report. While in deep bone marrow aplasia she developed fever, severe pain in the lower extremities, and swelling of the left femur. Blood culture showed Escherichia coli and A. hydrophila whereas pus culture from the soft tissue swelling showed the presence of A. hydrophila. Imaging studies showed diffuse osteolytic lesions. Patient received 5 months of intravenous and oral antibiotics and she improved clinically whereas the radiology findings persisted. PMID:27200197

  8. Effect of solar irradiation on extracellular enzymes of Aeromonas proteolytica

    NASA Technical Reports Server (NTRS)

    Foster, B. G.

    1973-01-01

    The bacterium Aeromonas proteolytica was selected for studying the effects of solar irradiation on extracellular enzymes because it produces an endopeptidase that is capable of degrading proteins and a hemolysin that is active in lysing human erythrocytes. Possible alterations in the rate of enzyme production in response to the test conditions are currently underway and are not available for this preliminary report. Completed viability studies are indicative that little difference exists among the survival curves derived for cells exposed to various components of ultraviolet irradiation in space.

  9. Development of In Vitro Correlate Assays of Immunity to Infection with Yersinia Pestis

    DTIC Science & Technology

    2007-05-01

    to Yersinia enterocolitica in mice. Med. Microbiol. Immunol. 181:333–338. 5. Boise, L. H., and C. M. Collins. 2001. Salmonella-induced cell lysis...666. 28. Mills, S. D., A. Boland, M. P. Sory, P. van der Smissen, C. Kerbourch, B. B. Finlay, and G. R. Cornelis. 1997. Yersinia enterocolitica induces...Heesemann, and B. Rouot. 1997. Interaction of Yersinia enterocolitica with macrophages leads to macrophage cell death through apoptosis. Infect. Immun

  10. Virulence factor-activity relationships (VFAR) with specific emphasis on Aeromonas species (spp.).

    PubMed

    Chopra, Ashok K; Graf, Joerg; Horneman, Amy J; Johnson, Judith A

    2009-01-01

    The human population most commonly inflicted with Aeromonas infection includes young children, the elderly and immunocompromised individuals. Importantly, the isolation rate of Aeromonas species from children suffering from diarrhea is similar in developing and developed countries. It is becoming clear that only a small subset of Aeromonas species belonging to a particular hybridization group causes disease in humans. Human infections with this pathogen occur by consuming contaminated food and water. Aeromonas species were isolated from wounds of patients during the tsunami in southern Thailand. Further, increased numbers of this pathogen were recovered from floodwater samples during Hurricane Katrina in New Orleans. Among various species of Aeromonas, A. hydrophila, A. caviae and A. veronii biovar sobria are mainly responsible for causing disease in humans. Our laboratory has isolated various virulence factors from a diarrheal isolate SSU of A. hydrophila and molecularly characterized them. In addition to various virulence factors produced by Aeromonas species, the status of the immune system plays an important role in inducing disease by this pathogen in the host. Taken together, we have made significant advances in better understanding the pathogenesis of Aeromonas infections, which will help in differentiating pathogenic from non-pathogenic aeromonads. This review covers virulence aspects of a clinical isolate of A. hydrophila.

  11. Clinical and Therapeutic Implications of Aeromonas Bacteremia: 14 Years Nation-Wide Experiences in Korea

    PubMed Central

    Jung, Dong Sik

    2016-01-01

    Background To elucidate the clinical presentation, antimicrobial susceptibility, and prognostic factors of monomicrobial Aeromonas bacteremia in order to determine the most effective optimal therapy. Materials and Methods We reviewed the medical records of Aeromonas bacteremia patients for the period January 2000 to December 2013 in a retrospective multi-center study. Results A total of 336 patient records were reviewed, with 242 having community-acquired bacteremia. The major clinical infections were of the hepatobiliary tract (50.6%) and peritonitis (18.5%), followed by primary bacteremia (17.9%). The infections usually occurred in patients with malignancy (42.3%), hepatic cirrhosis (39.3%), or diabetes mellitus (25.6%). High antimicrobial-resistance rates (15.5% for ceftriaxone, 15.5% for piperacillin/tazobactam) were noted. However, resistance to carbapenem and amikacin was only 9.8% and 3.0%, respectively. Aeromonas hydrophila (58.9%) was the most common pathogen, followed by Aeromonas caviae (30.4%). The severity of A. caviae bacteremia cases were less than that of A. hydrophila or Aeromonas veronii bacteremia (P <0.05). A. hydrophila showed higher antimicrobial resistance than did other Aeromonas species (P <0.05). Patients with hospital-acquired bacteremia were more likely to have severely abnormal laboratory findings and relatively high antimicrobial-resistance rates. Mortality was associated with metastatic cancer, shock, delayed use of appropriate antimicrobial agents, increased prothrombin time, and increased creatinine level (P <0.05). Conclusions Aeromonas species should be considered one of the causative agents of bacteremia in patients with intra-abdominal infections or malignancies. Although ceftriaxone-resistant Aeromonas bacteremia was not statistically related to mortality in this study, it was associated with severe clinical manifestations and laboratory abnormalities. Appropriate antibiotics, including carbapenem, should be administered early

  12. Differences in production of several extracellular virulence factors in clinical and food Aeromonas spp. strains.

    PubMed

    Pin, C; Marín, M L; Selgas, D; García, M L; Tormo, J; Casas, C

    1995-02-01

    Production of several extracellular virulence factors (lipase, protease and haemolysin) was compared in 15 Aeromonas spp. isolated from faeces of patients with Aeromonas-associated gastroenteritis and 81 strains isolated from food. Strains from food did not show differences in production of these factors when compared with strains isolated from faeces. However, if strains were considered in relation to autoagglutination (AA) character, the AA+ differed from AA- strains in lipase and protease production. Supernatant fluids of AA+ food and human strains showed 2.5-fold more protease production than that observed in AA- strains. These two characteristics of certain Aeromonas strains could be related with the more virulent capacity.

  13. Incidence and toxigenicity of Aeromonas hydrophila in seafood.

    PubMed

    Tsai, G J; Chen, T H

    1996-08-01

    Three selective media, Oxoid Aeromonas agar (OA), blood ampicillin agar (BA) and starch ampicillin agar (SA) were used to evaluate the presence of Aeromonas hydrophila in 66 samples of oyster, shrimp, fish and surimi products. Oyster had the highest incidence, with 50% positive, whilst no A. hydrophila was found in the surimi. Of the three selective media, BA displayed the highest recovery rate of A. hydrophila from seafood. Forty-eight isolates from this survey were tested for their capability to produce hemolysin and cytotoxin. Hemolysin was produced by 79.2% of the isolates and cytotoxin was produced by 91.7% of the isolates in brain heart infusion broth. One of the toxin-producing isolates from oyster, strain 8-169, was further tested for growth and toxin production in oyster, shrimp and fish at various temperatures. This particular isolate grew best and had highest toxin production in oyster. Hemolysin and cytotoxin were produced earlier at 28 degrees C than at 37 degrees C, and titers of hemolysin were also higher at 28 degrees C. At 5 degrees C, it was able to grow and produce hemolysin in oyster.

  14. Yersinia Type III Secretion System Master Regulator LcrF

    PubMed Central

    Schwiesow, Leah; Lam, Hanh

    2015-01-01

    Many Gram-negative pathogens express a type III secretion (T3SS) system to enable growth and survival within a host. The three human-pathogenic Yersinia species, Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica, encode the Ysc T3SS, whose expression is controlled by an AraC-like master regulator called LcrF. In this review, we discuss LcrF structure and function as well as the environmental cues and pathways known to regulate LcrF expression. Similarities and differences in binding motifs and modes of action between LcrF and the Pseudomonas aeruginosa homolog ExsA are summarized. In addition, we present a new bioinformatics analysis that identifies putative LcrF binding sites within Yersinia target gene promoters. PMID:26644429

  15. Structural Insights into Ail-Mediated Adhesion in Yersinia pestis

    SciTech Connect

    Yamashita, Satoshi; Lukacik, Petra; Barnard, Travis J.; Noinaj, Nicholas; Felek, Suleyman; Tsang, Tiffany M.; Krukonis, Eric S.; Hinnebusch, B. Joseph; Buchanan, Susan K.

    2012-01-30

    Ail is an outer membrane protein from Yersinia pestis that is highly expressed in a rodent model of bubonic plague, making it a good candidate for vaccine development. Ail is important for attaching to host cells and evading host immune responses, facilitating rapid progression of a plague infection. Binding to host cells is important for injection of cytotoxic Yersinia outer proteins. To learn more about how Ail mediates adhesion, we solved two high-resolution crystal structures of Ail, with no ligand bound and in complex with a heparin analog called sucrose octasulfate. We identified multiple adhesion targets, including laminin and heparin, and showed that a 40 kDa domain of laminin called LG4-5 specifically binds to Ail. We also evaluated the contribution of laminin to delivery of Yops to HEp-2 cells. This work constitutes a structural description of how a bacterial outer membrane protein uses a multivalent approach to bind host cells.

  16. Proteomic Characterization of Host Response to Yersinia pestis

    SciTech Connect

    Chromy, B; Perkins, J; Heidbrink, J; Gonzales, A; Murhpy, G; Fitch, J P; McCutchen-Maloney, S

    2004-05-11

    Host-pathogen interactions result in protein expression changes within both the host and the pathogen. Here, results from proteomic characterization of host response following exposure to Yersinia pestis, the causative agent of plague, and to two near neighbors, Y. pseudotuberculosis and Y. enterocolitica, are reported. Human monocyte-like cells were chosen as a model for macrophage immune response to pathogen exposure. Two-dimensional electrophoresis followed by mass spectrometry was used to identify host proteins with differential expression following exposure to these three closely related Yersinia species. This comparative proteomic characterization of host response clearly shows that host protein expression patterns are distinct for the different pathogen exposures, and contributes to further understanding of Y. pestis virulence and host defense mechanisms. This work also lays the foundation for future studies aimed at defining biomarkers for presymptomatic detection of plague.

  17. Sepsis and siderosis, Yersinia enterocolitica and hereditary haemochromatosis.

    PubMed

    Thwaites, Phoebe A; Woods, Marion L

    2017-01-04

    A 60-year-old woman was admitted with sepsis, relative bradycardia, CT evidence of numerous small liver abscesses and 'skin bronzing' consistent with hereditary haemochromatosis (HH). Yersinia enterocolitica O:9 infection was confirmed by serology specimens taken 10 days apart. Iron overload was detected, and homozygous C282Y gene mutation confirmed HH. Liver biopsy revealed grade IV siderosis with micronodular cirrhosis. Haemochromatosis is a common, inherited disorder leading to iron overload that can produce end-organ damage from excess iron deposition. Haemochromatosis diagnosis allowed aggressive medical management with phlebotomy achieving normalisation of iron stores. Screening for complications of cirrhosis was started that included hepatoma surveillance. Iron overload states are known to increase patient susceptibility to infections caused by lower virulence bacteria lacking sophisticated iron metabolism pathways, for example, Yersinia enterocolitica Although these serious disseminated infections are rare, they may serve as markers for occult iron overload and should prompt haemochromatosis screening.

  18. A numerical taxonomic study of Actinobacillus, Pasteurella and Yersinia.

    PubMed

    Sneath, P H; Stevens, M

    1985-10-01

    A numerical taxonomic study of strains of Actinobacillus, Pasteurella and Yersinia, with some allied bacteria, showed 23 reasonably distinct groups. These fell into three major areas. Area A contained species of Actinobacillus and Pasteurella: A. suis, A. equuli, A. lignieresii, P. haemolytica biovar A, P. haemolytica biovar T, P. multocida, A. actinomycetemcomitans, 'P. bettii', 'A. seminis', P. ureae and P. aerogenes. Also included in A was a composite group of Pasteurella pneumotropica and P. gallinarum, together with unnamed groups referred to as 'BLG', 'Mair', 'Ross' and 'aer-2'. Area B contained species of Yersinia: Y. enterocolitica, Y. pseudotuberculosis, Y. pestis and a group 'ent-b' similar to Y. enterocolitica. Area C contained non-fermenting strains: Y. philomiragia, Moraxella anatipestifer and a miscellaneous group 'past-b'. There were also a small number of unnamed single strains.

  19. Yersinia hepatic abscesses subsequent to long-term iron therapy.

    PubMed

    Leighton, P M; MacSween, H M

    1987-02-20

    A 71-year-old woman who had been receiving iron injections for at least ten years was admitted to the Dr Everett Chalmers Hospital, Fredericton, New Brunswick. The initial diagnosis was metastatic tumors in the liver, but after further evaluation, the initial diagnosis was corrected to multiple hepatic abscesses due to Yersinia enterocolitica. The liver biopsy showed abundant iron deposition. With the appropriate antibiotic treatment, the patient recovered.

  20. Distribution and Evolution of Yersinia Leucine-Rich Repeat Proteins

    PubMed Central

    Hu, Yueming; Huang, He; Hui, Xinjie; Cheng, Xi; White, Aaron P.

    2016-01-01

    Leucine-rich repeat (LRR) proteins are widely distributed in bacteria, playing important roles in various protein-protein interaction processes. In Yersinia, the well-characterized type III secreted effector YopM also belongs to the LRR protein family and is encoded by virulence plasmids. However, little has been known about other LRR members encoded by Yersinia genomes or their evolution. In this study, the Yersinia LRR proteins were comprehensively screened, categorized, and compared. The LRR proteins encoded by chromosomes (LRR1 proteins) appeared to be more similar to each other and different from those encoded by plasmids (LRR2 proteins) with regard to repeat-unit length, amino acid composition profile, and gene expression regulation circuits. LRR1 proteins were also different from LRR2 proteins in that the LRR1 proteins contained an E3 ligase domain (NEL domain) in the C-terminal region or an NEL domain-encoding nucleotide relic in flanking genomic sequences. The LRR1 protein-encoding genes (LRR1 genes) varied dramatically and were categorized into 4 subgroups (a to d), with the LRR1a to -c genes evolving from the same ancestor and LRR1d genes evolving from another ancestor. The consensus and ancestor repeat-unit sequences were inferred for different LRR1 protein subgroups by use of a maximum parsimony modeling strategy. Structural modeling disclosed very similar repeat-unit structures between LRR1 and LRR2 proteins despite the different unit lengths and amino acid compositions. Structural constraints may serve as the driving force to explain the observed mutations in the LRR regions. This study suggests that there may be functional variation and lays the foundation for future experiments investigating the functions of the chromosomally encoded LRR proteins of Yersinia. PMID:27217422

  1. Yersinia pestis Ail: multiple roles of a single protein

    PubMed Central

    Kolodziejek, Anna M.; Hovde, Carolyn J.; Minnich, Scott A.

    2012-01-01

    Yersinia pestis is one of the most virulent bacteria identified. It is the causative agent of plague—a systemic disease that has claimed millions of human lives throughout history. Y. pestis survival in insect and mammalian host species requires fine-tuning to sense and respond to varying environmental cues. Multiple Y. pestis attributes participate in this process and contribute to its pathogenicity and highly efficient transmission between hosts. These include factors inherited from its enteric predecessors; Y. enterocolitica and Y. pseudotuberculosis, as well as phenotypes acquired or lost during Y. pestis speciation. Representatives of a large Enterobacteriaceae Ail/OmpX/PagC/Lom family of outer membrane proteins (OMPs) are found in the genomes of all pathogenic Yersiniae. This review describes the current knowledge regarding the role of Ail in Y. pestis pathogenesis and virulence. The pronounced role of Ail in the following areas are discussed (1) inhibition of the bactericidal properties of complement, (2) attachment and Yersinia outer proteins (Yop) delivery to host tissue, (3) prevention of PMNL recruitment to the lymph nodes, and (4) inhibition of the inflammatory response. Finally, Ail homologs in Y. enterocolitica and Y. pseudotuberculosis are compared to illustrate differences that may have contributed to the drastic bacterial lifestyle change that shifted Y. pestis from an enteric to a vector-born systemic pathogen. PMID:22919692

  2. Yersinia enterocolitica-mediated degradation of neutrophil extracellular traps (NETs).

    PubMed

    Möllerherm, Helene; Neumann, Ariane; Schilcher, Katrin; Blodkamp, Stefanie; Zeitouni, Nathalie E; Dersch, Petra; Lüthje, Petra; Naim, Hassan Y; Zinkernagel, Annelies S; von Köckritz-Blickwede, Maren

    2015-12-01

    Neutrophil extracellular trap (NET) formation is described as a tool of the innate host defence to fight against invading pathogens. Fibre-like DNA structures associated with proteins such as histones, cell-specific enzymes and antimicrobial peptides are released, thereby entrapping invading pathogens. It has been reported that several bacteria are able to degrade NETs by nucleases and thus evade the NET-mediated entrapment. Here we studied the ability of three different Yersinia serotypes to induce and degrade NETs. We found that the common Yersinia enterocolitica serotypes O:3, O:8 and O:9 were able to induce NETs in human blood-derived neutrophils during the first hour of co-incubation. At later time points, the NET amount was reduced, suggesting that degradation of NETs has occurred. This was confirmed by NET degradation assays with phorbol-myristate-acetate-pre-stimulated neutrophils. In addition, we found that the Yersinia supernatants were able to degrade purified plasmid DNA. The absence of Ca(2+) and Mg(2+) ions, but not that of a protease inhibitor cocktail, completely abolished NET degradation. We therefore postulate that Y. enterocolitica produces Ca(2+)/Mg(2+)-dependent NET-degrading nucleases as shown for some Gram-positive pathogens.

  3. Hemolytic and proteolytic activities of Aeromonas hydrophila and Aeromonas veronii biovar sobria in broth and salmon extract at different temperatures.

    PubMed

    González-Rodríguez, María-Nieves; Santos, Jesús A; Otero, Andrés; García-López, Maria-Luisa

    2004-02-01

    Expression of hemolytic and proteolytic activities throughout the growth cycle was investigated with two enterotoxic aeromonad strains assigned to the species Aeromonas hydrophila and Aeromonas veronii biovar sobria. Although growth kinetic data were dependent on strain, temperature, and substrate, maximum populations attained were higher than 9 log CFU/ml in aerated tryptone soya broth plus yeast extract (TSBYE) and salmon extract within the range 4 to 28 degrees C. For both strains in TSBYE, variable amounts of hemolytic activity were first detected at any temperature when aeromonad counts were over 9 log CFU/ml. Afterwards, this activity increased up to similar levels (109 to 112 hemolytic units per ml) without a significant increase in populations. Salmon extract supported hemolysin synthesis at 28 but not 4 degrees C. Proteolytic activity of the A. hydrophila strain was only expressed in salmon extract at 28 degrees C, whereas A. veronii biovar sobria did at 28 degrees C in both substrates and at 10 degrees C in TSBYE.

  4. 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.

  5. 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...

  6. Isolation and characterization of Aeromonas species from an eutrophic tropical estuary.

    PubMed

    Marcel, Kouassi Aka; Antoinette, Adingra Ama; Mireille, Dosso

    2002-12-01

    Isolation and characterization of Aeromonas species were undertaken in the Ebrié lagoon (Abidjan, Côte d'Ivoire) over a one year period. Overall 63% of 501 water samples were identified as positive for Aeromonas spp. A. sobria, A. hydrophila and A. caviae represent respectively 49.20%, 20.63% and 30.15% of the positive samples. Thirty nine of the positive samples were recovered from surface water samples; while 24 bottom water samples were positive for Aeromonas. Aeromonas species are most frequently (82.53) present in the Ebrié lagoon urban area during the rainy and flood seasons when the salinity is low and below 10 per thousand. A lower isolation frequency is noticed during the dry season when water salinity is over 10 per thousand. Finally, a higher isolation frequency occurred in samples with highest counts of Escherichia coli.

  7. Aeromonas hydrophila meningitis and fulminant sepsis in preterm newborn: A case report and review of literature.

    PubMed

    Kali, A; Kalaivani, R; Charles, Pmv; Seetha, K S

    2016-01-01

    Neonatal meningitis is a lethal infection occurring in the 1st month of life. The risk of developing permanent neurological sequels is high among the neonates who survive. Bacterial pathogens are commonly associated with this condition. Aeromonas is a Gram-negative bacteria of aquatic habitat. Although isolation of Aeromonas species from neonates with blood stream infection is infrequently reported, neonatal meningitis caused by Aeromonas is exceedingly rare. We present a case of fulminant sepsis and meningitis caused by Aeromonas hydrophila in a preterm newborn male. The bacteria was isolated in culture from blood and cerebrospinal fluid. In spite of targeted antibiotics and supportive therapy, the baby failed to respond and died on the 12th day of life.

  8. Draft genome sequences of three Aeromonas hybrophila isolates from catfish and tilapia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila is a Gram-negative bacteria that is particularly adapted to freshwater environments and can cause severe infections in fish and humans. Here we report the draft genomes of three A. hydrophila catfish and tilapia isolates....

  9. 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.

  10. Differential regulation of the hmsCDE operon in Yersinia pestis and Yersinia pseudotuberculosis by the Rcs phosphorelay system.

    PubMed

    Guo, Xiao-Peng; Ren, Gai-Xian; Zhu, Hui; Mao, Xu-Jian; Sun, Yi-Cheng

    2015-02-12

    Yersinia pestis, the agent of plague, forms a biofilm in its flea vector to enhance transmission. Y. pestis biofilm development is positively regulated by hmsT and hmsD, encoding diguanylate cyclases (DGCs) involved in synthesis of the bacterial second messenger c-di-GMP. rcsA, encoding an auxiliary protein in Rcs phosphorelay, is nonfunctional in Y. pestis, while in Yersinia pseudotuberculosis, rcsA is functional and represses biofilms. Previously we showed that Rcs phosphorelay negatively regulates transcription of hmsT in Y. pestis and its ancestor Yersinia pseudotuberculosis. In this study, we show that Rcs positively regulates hmsCDE operon (encoding HmsD) in Y. pestis; while in the presence of functional rcsA, Rcs represses hmsCDE operon in Y. pseudotuberculosis. Loss of rcsA's function in Y. pestis not only causes derepression of hmsT but also causes activation of hmsD, which may account for the increased biofilm formation in Y. pestis. In addition, differential regulation of the two DGCs, HmsT and HmsD by Rcs may help Y. pestis to adapt to different environment.

  11. Comparison of Systems for Identification and Differentiation of Species within the Genus Yersinia

    PubMed Central

    Neubauer, Heinrich; Sauer, Thomas; Becker, Heinz; Aleksic, Stojanca; Meyer, Hermann

    1998-01-01

    Of four tested identification systems (API 20E, API Rapid 32 IDE, Micronaut E, and the PCR-based Yersinia enterocolitica Amplification Set), API 20E is still the system of choice for identifying pathogenic Yersinia isolates. It provides the highest sensitivity both at the genus and at the species level and has the best cost-effectiveness correlation. PMID:9774596

  12. Behavior of Avirulent Yersinia pestis in Liquid Whole Egg as Affected by Antimicrobials and Thermal Pasteurization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yersinia spp. is a psychrotrophic bacterium that can grow at temperatures as low as minus two degrees Celsius, and is known to contaminate shell eggs in the United States and shell eggs and liquid egg in South America. A study was performed to determine the thermal sensitivity of avirulent Yersinia...

  13. Strategies used by Yersinia enterocolitica to evade killing by the host: thinking beyond Yops.

    PubMed

    Dhar, Mahesh Shanker; Virdi, Jugsharan Singh

    2014-02-01

    Yersinia enterocolitica is an important gastrointestinal pathogen. Its pathogenicity has been attributed primarily to the plasmid encoded Yersinia outer proteins or Yops that are known to subvert the immune system. This review, however, highlights the role of Yop-independent mechanisms that help Y. enterocolitica evade immune system and contribute significantly to its survival in the host.

  14. Yersinia pestis YopD 150-287 Fragment is Partially Unfolded in the Native State

    DTIC Science & Technology

    2007-11-17

    Hoiczyk, G. Blobel, Polymerization of a single protein of the pathogen Yersinia enterocolitica into needles punctures eukaryotic cells, Proc. Natl...12] C.B. Trame, D.B. McKay, Structure of the Yersinia enterocolitica molecular-chaperone protein SycE, Acta Crystallogr. D Biol. Crys- tallogr. 59

  15. Divergence among genes encoding the elongation factor Tu of Yersinia Species.

    PubMed

    Isabel, Sandra; Leblanc, Eric; Boissinot, Maurice; Boudreau, Dominique K; Grondin, Myrian; Picard, François J; Martel, Eric A; Parham, Nicholas J; Chain, Patrick S G; Bader, Douglas E; Mulvey, Michael R; Bryden, Louis; Roy, Paul H; Ouellette, Marc; Bergeron, Michel G

    2008-11-01

    Elongation factor Tu (EF-Tu), encoded by tuf genes, carries aminoacyl-tRNA to the ribosome during protein synthesis. Duplicated tuf genes (tufA and tufB), which are commonly found in enterobacterial species, usually coevolve via gene conversion and are very similar to one another. However, sequence analysis of tuf genes in our laboratory has revealed highly divergent copies in 72 strains spanning the genus Yersinia (representing 12 Yersinia species). The levels of intragenomic divergence between tufA and tufB sequences ranged from 8.3 to 16.2% for the genus Yersinia, which is significantly greater than the 0.0 to 3.6% divergence observed for other enterobacterial genera. We further explored tuf gene evolution in Yersinia and other Enterobacteriaceae by performing directed sequencing and phylogenetic analyses. Phylogenetic trees constructed using concatenated tufA and tufB sequences revealed a monophyletic genus Yersinia in the family Enterobacteriaceae. Moreover, Yersinia strains form clades within the genus that mostly correlate with their phenotypic and genetic classifications. These genetic analyses revealed an unusual divergence between Yersinia tufA and tufB sequences, a feature unique among sequenced Enterobacteriaceae and indicative of a genus-wide loss of gene conversion. Furthermore, they provided valuable phylogenetic information for possible reclassification and identification of Yersinia species.

  16. Prevalence and molecular characterization of Aeromonas spp. in ready-to-eat foods in Italy.

    PubMed

    Villari, P; Crispino, M; Montuori, P; Stanzione, S

    2000-12-01

    A survey was carried out in Italy to ascertain the prevalence of Aeromonas spp. in ready-to-eat foods (vegetables, cheeses, meat products, and ice creams) and the level of molecular heterogeneity of the isolates found by macrorestriction analysis of genomic DNA with pulsed-field gel electrophoresis (PFGE). In total, 46 (14.4%) of the 320 food samples examined were found positive for Aeromonas spp. The highest percentages of isolation were discovered in vegetables, particularly lettuce (45.0%), endive (40.0%), and rucola (20.0%). Ricotta was the only cheese type analyzed that showed a high frequency of isolation (45.0%). Among meat products, salami and raw ham (25.0% of samples positive) and, to a lesser extent, baloney (5.0%) were found positive for Aeromonas spp. Aeromonas hydrophila was the most common isolate from foods of animal origin, whereas Aeromonas caviae was the dominant species in vegetables. No motile aeromonads were found in ice cream samples. Aeromonas isolates showed a high level of genetic heterogeneity, because 24 PFGE patterns were identified among 27 A. hydrophila strains and 20 PFGE patterns were found in 23 A. caviae isolates. In conclusion, consumers of ready-to-eat foods in Italy are regularly exposed to many genetically distinct strains of A. hydrophila and A. caviae without evident signs of malaise, and therefore, few of these strains, if any, are likely to be pathogenic.

  17. Isolation of Yersinia spp. from cases of diarrhoea in Iraqi infants and children.

    PubMed

    Kanan, T A; Abdulla, Z A

    2009-01-01

    All 250 children presenting with diarrhoea at 2 teaching hospitals in Mosul, Iraq over a 9-month period were studied for the presence of Yersinia spp. in stools by cold-enrichment culture at 4 degrees C for 21 days. Pathogenicity of the isolated Yersinia was determined. Antibodies to Y. enterocolitica were raised for rapid Yersinia detection in the stool. Yersinia spp. were isolated from the stools of only 4 patients; 3 isolates were identified as Y. enterocolitica and 1 was Y. pseudotuberculosis. The blood culture was also positive for Y. enterocolitica in 1 case. The antibiogram test for the isolated Yersinia was determined. Cross-reaction between Y. pseudotuberculosis and Salmonella typhi or S. paratyphi B, and between Y. enterocolitica and Brucella was detected serologically.

  18. Prevalence and genetic diversity of enteropathogenic Yersinia spp. in pigs at farms and slaughter in Lithuania.

    PubMed

    Novoslavskij, Aleksandr; Šernienė, Loreta; Malakauskas, Alvydas; Laukkanen-Ninios, Riikka; Korkeala, Hannu; Malakauskas, Mindaugas

    2013-04-01

    The prevalence of enteropathogenic Yersinia spp. in pigs at farms and slaughter in relation to potential farming risk factors in Lithuania was examined. Pig faeces and carcase swab samples from 11 farms were studied at slaughterhouses. Nine of the 11 farms were visited again 3-5 months later, and pooled feacal samples and environmental samples were collected. Pathogenic Yersinia enterocolitica was found in 64% and Yersinia pseudotuberculosis in 45% of the sampled pig farms. All obtained isolates belonged to bioserotypes 4/O:3 and 2/O:3, respectively. Low biosecurity level was associated with a high prevalence of Y. enterocolitica on farms. Characterization with PFGE of 64 Y. enterocolitica and 27 Y. pseudotuberculosis isolates revealed seven and two different genotypes, respectively. Dominant enteropathogenic Yersinia spp. genotypes were obtained in both pig feacal and carcase samples. The high contamination of pig carcases (25%) with enteropathogenic Yersinia spp. may be an important factor contributing to the high incidence of human yersiniosis in Lithuania.

  19. Contribution of nuclease to the pathogenesis of Aeromonas hydrophila

    PubMed Central

    Ji, Yachan; Li, Jinquan; Qin, Zhendong; Li, Aihua; Gu, Zemao; Liu, Xiaoling; Lin, Li; Zhou, Yang

    2015-01-01

    Aeromonas hydrophila is a gram-negative bacterium that is widely distributed in aquatic environments and can cause septicemia in both fish and humans. However, the underlying mechanisms leading to severe infection are not well understood. In this study, an A. hydrophila nuclease (ahn) deletion mutant was constructed to investigate its contribution to pathogenesis. This mutant did not differ from the wild-type strain in terms of its growth or hemolytic phenotype. However, the ahn-deficient mutant was more susceptible to being killed by fish macrophages and mouse blood in vitro. Furthermore, evidence obtained using both fish and murine infection models strongly indicated that the inactivation of Ahn impaired the ability of A. hydrophila to evade innate immune clearance in vivo. More importantly, the virulence of the mutant was attenuated in both fish and mice, with reductions in dissemination capacities and mortality rates. These findings implicate Ahn in A. hydrophila virulence, with important functions in evading innate immune defenses. PMID:26039879

  20. Gastroenteritis caused by Aeromonas trota in a child.

    PubMed Central

    Reina, J; Lopez, A

    1996-01-01

    A case of acute diarrhoea caused by Aeromonas trota (formerly HG 13 group) in a Spanish child is reported. The strain was isolated in the faeces using the CIN agar (cefsulodin-irgasan-novobiocin) culture media. The strain was initially identified as A sobria by the commercial GNI card and API 20E biochemical systems. The strain was, however, VogesProskauer and sucrose negative, so complementary tests of cellobiose fermentation and gluconate oxidation were performed. These tests, together with the strain susceptibility to ampicillin (MIC 1 microgram/ml) and carbenicillin (MIC < 16 micrograms/ml) led to the final identification of A trota. The microbiological characteristics of this new species and the principal tests required for its identification are presented. The isolation, for the first time, of A trota in the Mediterranean area confirms the suspected worldwide distribution of this species. PMID:8655689

  1. Virulence and cytotoxicity of seafood borne Aeromonas hydrophila

    PubMed Central

    Illanchezian, Seethalakshmi; Jayaraman, SathishKumar; Manoharan, Muthu Saravanan; Valsalam, Saritha

    2010-01-01

    The present study was conducted to determine the virulence and cytotoxicity of Aeromonas hydrophila strains isolated from seafood samples collected from 5 major fish markets in Chennai, Tamil Nadu, India. Among 73 A. hydrophila strains isolated from fish and shrimp samples, 86.3% exhibited haemolysis, 78.1% produced slime, 98.63% produced protease and also demonstrated cytotoxicity on Vero cells. Cell shrinkage, detachment and rounding of Vero cells were recorded as cytotoxic changes. Only one strain did not show haemolysis, slime production, proteolytic activity and cytotoxicity on treatment with Vero cells. Positive correlation was observed between proteolytic activity and cytotoxicity irrespective of haemolytic activity of the strains. These results demonstrated the presence of wide spread, pathogenically characterized, cytotoxic seafood borne A. hydrophila in Chennai. PMID:24031577

  2. Prevalence and distribution of Aeromonas hydrophila in the United States.

    PubMed Central

    Hazen, T C; Fliermans, C B; Hirsch, R P; Esch, G W

    1978-01-01

    The abundance of Aeromonas hydrophila was measured in 147 natural aquatic habitats in 30 states and Puerto Rico. Viable cell counts were used to estimate density at all sites by using Rimler-Shotts medium, a differential presumptive medium for A. hydrophila. Temperature, pH, conductivity, salinity, and turbidity were measured simultaneously with water sample collection. The density of A. hydrophila was higher in lotic than in lentic systems. Saline systems had higher densities of A. hydrophila than did freshwater systems. A. hydrophila could not be isolated from extremely saline, thermal, or polluted waters, even though it was found over wide ranges of salinity, conductivity, temperature, pH, and turbidity. Of the water quality parameters measured, only conductivity was significantly regressed with density of A. hydrophila. PMID:31839

  3. Evaluation of an in vitro cell assay to select attenuated bacterial mutants of Aeromonas hydrophila and Edwardsiella tarda to channel catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both Aeromonas hydrophila (causative agent of motile aeromonas septicemia) and Edwardsiella tarda (causative agent of enteric septicemia) are Gram-negative bacteria widely distributed in aquatic environments, affecting many fish species worldwide, including channel catfish and tilapia. To control ba...

  4. [Stationary and migratory avifauna as reservoirs of Salmonella, Yersinia and Campylobacter].

    PubMed

    Levrè, E; Valentini, P; Brunetti, M; Sacchelli, F

    1989-01-01

    Domestic and wild animals have been always considered very important as reservoir of agents of human infections. Particularly birds, because of their great mobility from a continent to another or within the limits of the same ecosystem may transfer pathogenic micro-organisms. The present survey was undertaken in order to evaluate the presence of Campylobacter, Yersinia and Salmonella in migratory and permanent birds. During the period October 1986 to March 1988 intestinal loops were collected from a total of 217 birds representing 17 different species shot, during hunting seasons, in the inland of Versilia in the district of Lucca. Each sample was divided into three parts and examined for the presence of Campylobacter, Yersinia and Salmonella. Campylobacter was isolated from 74 of the 217 birds examined (34.10%). Yersinia was recovered from 26 birds (11.98%), while only 8 birds (3.68%) harboured Salmonella. Most of the samples carried only one of the three bacterial genera investigated while 9 harboured at the same time Yersinia and Campylobacter, 1 Salmonella and Campylobacter, and 1 Salmonella, Yersinia and Campylobacter. Campylobacter spp.: On the ground of Lior's biotyping scheme, the 74 strains, isolated from 16 of the 17 species of birds examined, have assigned to three biochemically different species. C. coli was the most commonly isolated followed by C. jejuni and C. laridis. Of the 54 isolates of C. coli 30 belonged to biotype I and 24 to biotype II. 19 C. jejuni organisms were differentiated into 5 belonging to biotype I and 14 to biotype II. The only C. laridis isolated belonged to biotype I. Yersinia spp.: 37 strains belonging to the genus Yersinia were isolated from 26 birds. In 10 samples different types of Yersinia were identified. Most of the strains could be ascribed to Yersinia enterocolitica (28 strains), 3 to Yersinia frederiksenii, 3 to Yersinia intermedia and 1 to Yersinia pseudotuberculosis. 2 strains were identified as atypical Yersinia

  5. Aeromonas and Plesiomonas species from scarlet ibis (Eudocimus ruber) and their environment: monitoring antimicrobial susceptibility and virulence.

    PubMed

    Castelo-Branco, Débora Souza Collares Maia; Silva, Aline Lobão da; Monteiro, Frederico Ozanan Barros; Guedes, Glaucia Morgana de Melo; Sales, Jamille Alencar; Oliveira, Jonathas Sales de; Maia Junior, José Erisvaldo; Miranda, Stefânia Araújo; Sidrim, José Júlio Costa; Alencar, Lucas Pereira de; Brilhante, Raimunda Sâmia Nogueira; Cordeiro, Rossana de Aguiar; Bandeira, Tereza de Jesus Pinheiro Gomes; Pereira Neto, Waldemiro de Aquino; Rocha, Marcos Fábio Gadelha

    2017-01-01

    The present study aimed at evaluating the role of captive scarlet ibises (Eudocimus ruber) and their environment as reservoirs of Aeromonas spp. and Plesiomonas spp., and analyzing the in vitro antimicrobial susceptibility and virulence of the recovered bacterial isolates. Thus, non-lactose and weak-lactose fermenting, oxidase positive Gram-negative bacilli were recovered from cloacal samples (n = 30) of scarlet ibises kept in a conservational facility and from water samples (n = 30) from their environment. Then, the antimicrobial susceptibility, hemolytic activity and biofilm production of the recovered Aeromonas spp. and Plesiomonas shigelloides strains were assessed. In addition, the virulence-associated genes of Aeromonas spp. were detected. Ten Aeromonas veronii bv. sobria, 2 Aeromonas hydrophila complex and 10 P. shigelloides were recovered. Intermediate susceptibility to piperacillin-tazobactam and cefepime was observed in 2 Aeromonas spp. and 1 P. shigelloides, respectively, and resistance to gentamicin was observed in 4 P. shigelloides. The automated susceptibility analysis revealed resistance to piperacillin-tazobactam and meropenem among Aeromonas spp. and intermediate susceptibility to gentamicin among P. shigelloides. All Aeromonas isolates presented hemolytic activity, while 3 P. shigelloides were non-hemolytic. All Aeromonas spp. and 3/10 P. shigelloides were biofilm-producers, at 28 °C, while 10 Aeromonas spp. and 6/10 P. shigelloides produced biofilms, at 37 °C. The most prevalent virulence genes of Aeromonas spp. were asa1 and ascV. Scarlet ibises and their environment harbour potentially pathogenic bacteria, thus requiring monitoring and measures to prevent contamination of humans and other animals.

  6. Occurrence of motile Aeromonas in municipal drinking water and distribution of genes encoding virulence factors.

    PubMed

    Pablos, Manuel; Rodríguez-Calleja, Jose M; Santos, Jesús A; Otero, Andrés; García-López, María-Luisa

    2009-10-31

    Aeromonas-associated cases of gastroenteritis are generally considered waterborne. The purpose of this study was to evaluate the potential microbiological risk associated with the presence of these bacteria in public drinking water. Over a period of one year, 132 drinking-water samples were monitored in León (NW of Spain, 137,000 inhabitants) for mandatory drinking-water standards and the occurrence of Aeromonas spp. Samples were taken at the municipal water treatment plant, one storage facility, and two public artesian drinking-water fountains. Because of low numbers of coliforms or Clostridium perfringens, the non-compliance rate with microbial standards was 3.8% whereas the percentage of positive samples for motile mesophilic Aeromonas was 26.5%. For all but two samples, Aeromonas was recovered between October and early March when the temperature was below 14 degrees C and the residual chlorine ranged from 0.21 to 0.72 mg/l. An apparent relationship was observed between rainfall and the incidence of Aeromonas. The 35 selected Aeromonas isolates were identified as A. caviae and A. media. The alt and laf genes were present in all isolates, the aerA gene was present in six isolates, and the four remaining genes investigated (hlyA, ast, stx1 and stx2) were absent. The combinations of putative virulence genes were: aerA(-)/hlyA(-)/alt(+)/ast(-)/laf(+)/stx1(-)/stx2(-) (82.9%) and aerA(+)/hlyA(-)/alt(+)/ast(-)/laf(+)/stx1(-)/stx2(-) (17.1%). None of the isolates bore plasmids. As Aeromonas strains harbouring two or more virulence-associated genes have the potential to cause disease by direct transmission via drinking water or by water use in food preparation, it would be advisable to control excessive numbers of these bacteria in drinking-water supplies.

  7. Analysing the lag-growth rate relationship of Yersinia enterocolitica.

    PubMed

    Pin, Carmen; García, de Fernando Gonzalo D; Ordóñez, Juan A; Baranyi, József

    2002-03-01

    A generalised z-value concept has been applied to analyse the relationship between the lag and the growth rate of Yersinia enterocolitica at a range of temperature, atmospheric carbon dioxide and oxygen percentages. The product of the specific growth rate and the lag (the "work to be done" during the lag phase) is found to be independent of temperature. However, it does depend on the CO2 and O2 concentrations, though the effect of oxygen was less noticeable than the effect of carbon dioxide.

  8. Yersinia enterocolitica strains isolated from beavers (Castor fiber).

    PubMed

    Platt-Samoraj, A; Syczyło, K; Bancerz-Kisiel, A; Szczerba-Turek, A; Giżejewska, A; Szweda, W

    2015-01-01

    Pseudocloacal swabs and palatine tonsils from beavers have been examined for the Yersinia enterocolitica presence. Thirty-six samples from 24 beavers were collected and subjected to bacteriological examinations including sero- and biotypisation. Amplicons confirmed by PCR as Y. enterocolitica were sequenced. Positive samples originated from 4 out of the 24 beavers (16.7 %) and all the strains belonged to biotype 1A. The study suggested that Y. enterocolitica could be isolated from beavers, which may therefore be treated as a reservoir, a significant factor of water contamination and a vector of the Y. enterocolitica.

  9. Prevalence of Yersinia Species in Traditional and Commercial Dairy Products in Isfahan Province, Iran

    PubMed Central

    Rahimi, Ebrahim; Sepehri, Sara; Safarpoor Dehkordi, Farhad; Shaygan, Shima; Momtaz, Hassan

    2014-01-01

    Background: Yersinia species, especially Yersinia enterocolitica, are considered as the most prevalent milk-borne pathogens. Several serological and molecular techniques have been developed for rapid and safe diagnosis of yersiniosis. Objectives: This study was carried out to assess the prevalence rate of Yersinia species, especially Y. enterocolitica, in milk and dairy products in Isfahan province, Iran. Materials and Methods: A total of 285 commercial and traditional dairy products as well as 267 pasteurized and raw milk samples were collected during one year. The samples were studied by culturing and the positive-culture samples were investigated using PCR techniques. Results: The results of culture showed that 52 (9.42%) and 28 (5.07%) of the total 552 milk and dairy samples were positive for presences of Yersinia species and Y. enterocolitica, respectively. Totally, 24 of 28 Y. enterocolitica isolates by culture were positive in PCR test (4.59%). Raw cow milk and traditional cheese had the highest prevalence of Yersinia species and Y. enterocolitica, respectively. There were no positive results for pasteurized cow milk, raw camel milk, commercial ice cream, commercial cheese, yoghurt, Doogh, butter and curd. Yersinia species and Y. enterocolitica had the highest prevalence in autumn (15.15% and 10.6%, respectively). Significant differences regarding P < 0.05 were observed between the presences of Yersinia species and Y. enterocolitica in various samples and seasons. Conclusions: Sanitation and pasteurization are the best ways to increase the microbial quality and particularly decrease the load of Yersinia species. The ability of Yersinia species to growth in Doogh, yoghurt, curd and butter is very low. PMID:25147698

  10. Yersinia spp. Identification Using Copy Diversity in the Chromosomal 16S rRNA Gene Sequence.

    PubMed

    Hao, Huijing; Liang, Junrong; Duan, Ran; Chen, Yuhuang; Liu, Chang; Xiao, Yuchun; Li, Xu; Su, Mingming; Jing, Huaiqi; Wang, Xin

    2016-01-01

    API 20E strip test, the standard for Enterobacteriaceae identification, is not sufficient to discriminate some Yersinia species for some unstable biochemical reactions and the same biochemical profile presented in some species, e.g. Yersinia ferderiksenii and Yersinia intermedia, which need a variety of molecular biology methods as auxiliaries for identification. The 16S rRNA gene is considered a valuable tool for assigning bacterial strains to species. However, the resolution of the 16S rRNA gene may be insufficient for discrimination because of the high similarity of sequences between some species and heterogeneity within copies at the intra-genomic level. In this study, for each strain we randomly selected five 16S rRNA gene clones from 768 Yersinia strains, and collected 3,840 sequences of the 16S rRNA gene from 10 species, which were divided into 439 patterns. The similarity among the five clones of 16S rRNA gene is over 99% for most strains. Identical sequences were found in strains of different species. A phylogenetic tree was constructed using the five 16S rRNA gene sequences for each strain where the phylogenetic classifications are consistent with biochemical tests; and species that are difficult to identify by biochemical phenotype can be differentiated. Most Yersinia strains form distinct groups within each species. However Yersinia kristensenii, a heterogeneous species, clusters with some Yersinia enterocolitica and Yersinia ferderiksenii/intermedia strains, while not affecting the overall efficiency of this species classification. In conclusion, through analysis derived from integrated information from multiple 16S rRNA gene sequences, the discrimination ability of Yersinia species is improved using our method.

  11. Diversity, persistence, and virulence of Aeromonas strains isolated from drinking water distribution systems in Sweden.

    PubMed Central

    Kühn, I; Allestam, G; Huys, G; Janssen, P; Kersters, K; Krovacek, K; Stenström, T A

    1997-01-01

    The Aeromonas populations in 13 Swedish drinking water distribution systems, representing different treatments, were investigated. From each system, water samples were collected four times during the period from May to September 1994 from raw water and water after treatment and at two to five sites within the distribution system. In total, 220 water samples were collected. From samples containing presumptive Aeromonas, up to 32 colonies were analyzed by the PhenePlate Aeromonas (PhP-AE) system, which is a highly discriminating biochemical fingerprinting method. Selected isolates from different phenotypes (PhP types) were further identified by the API 20 NE system and by gas-liquid chromatography analysis of fatty acid methyl esters (FAMEs). Selected isolates were also assayed for their potential to produce hemolysin and cytotoxin and for their ability to adhere to human intestinal cells. In total, 117 water samples (53%) contained presumptive Aeromonas which numbered up to 10(6) CFU/100 ml in raw water and up to 750 CFU/100 ml in tap water. Among the 2,117 isolates that were subjected to typing by the PhP-AE system, more than 300 distinct PhP types were found, of which the majority occurred only sporadically. Raw (surface) water samples usually contained many different PhP types, showing high diversity indices (Di) (median Di = 0.95). The Aeromonas populations in samples collected from within the distribution systems were less diverse (median Di = 0.58) and were often dominated by one major PhP type that was found on several sampling occasions. Seventeen such major PhP types could be found and were represented in 1,037 isolates (49%). Identification by API 20 NE and FAME analysis revealed that most of the major PhP types were Aeromonas hydrophila or belonged to unidentified Aeromonas species. Hemolysin and cytotoxin production was observed in most major PhP types (representing 87 and 54% of the assayed isolates, respectively), and adherence was found in 89% of the

  12. The occurrence of Salmonella, Campylobacter and Yersinia spp. in river and lake waters.

    PubMed

    Arvanitidou, M; Stathopoulos, G A; Constantinidis, T C; Katsouyannopoulos, V

    1995-05-01

    In order to assess Salmonella, Campylobacter and Yersinia spp. occurrence in surface waters and to compare it with the standard faecal indicator bacteria, 86 river and lake samples, from eight sampling sites in Northern Greece were examined for the presence of these pathogens in parallel to total and faecal coliforms and faecal streptococci. A total of 17 Salmonellae, 14 Campylobacters and 9 Yersiniae were isolated. Only in Salmonella positive samples the geometric means of total and faecal coliforms were found significantly higher (p < 0.01) than in the negative samples, whereas the presence of Campylobacters and Yersiniae may not be predicted by the standard indicator bacteria.

  13. The ail gene is present in some Yersinia enterocolitica biotype 1A strains.

    PubMed

    Sihvonen, Leila M; Hallanvuo, Saija; Haukka, Kaisa; Skurnik, Mikael; Siitonen, Anja

    2011-03-01

    One chromosomal virulence marker of Yersinia is the gene ail, which encodes Ail, an outer membrane protein that promotes attachment and invasion. A high correlation has been found between the ail gene and the virulence of Yersinia. Here, we report two Yersinia enterocolitica biotype 1A strains that are usually nonpathogenic and carry the ail gene. The ail gene sequences of biotype 1A strains displayed similarity to the bioserotype 1B/O:8 strain 8081. The finding suggests that ail-based detection methods for Y. enterocolitica alone are insufficient to detect real pathogenic strains.

  14. Identification and Molecular Characterization of the Homogentisate Pathway Responsible for Pyomelanin Production, the Major Melanin Constituents in Aeromonas media WS

    PubMed Central

    Wang, He; Qiao, Yunqian; Chai, Baozhong; Qiu, Chenxi; Chen, Xiangdong

    2015-01-01

    The pigmentation of many Aeromonas species has been thought to be due to the production of a L-DOPA (L-3,4-dihydroxyphenylalanine) based melanin. However, in this study we found that although L-DOPA synthesis occurs in the high-melanin-yielding Aeromonas media strain WS, it plays a minor, if any, role in pigmentation. Instead, the pigmentation of A. media strain WS is due to the production of pyomelanin through HGA (homogentisate). Gene products of phhA (encodes phenylalanine hydroxylase), tyrB and aspC (both encode aromatic amino acid aminotransferase), and hppD (encodes 4-hydroxyphenylpyruvate dioxygenase) constitute a linear pathway of converting phenylalanine to HGA and disruption of any one of these genes impairs or blocks pigmentation of A. media strain WS. This HGA biosynthesis pathway is widely distributed in Aeromonas, but HGA is only detectable in the cultures of pigmented Aeromonas species. Heterologous expression of HppD from both pigmented and non-pigmented Aeromonas species in E. coli leads to the production of pyomelanin and thus pigmentation, suggesting that most Aeromonas species have the critical enzymes to produce pyomelanin through HGA. Taken together, we have identified a widely conserved biosynthesis pathway of HGA based pyomelanin in Aeromonas that may be responsible for pigmentation of many Aeromonas species. PMID:25793756

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: A recent epidemic outbreak of motile Aeromonas septicemia of catfish caused by highly virulent Aeromonas hydrophila is a major threat to the catfish industry in the southeastern United States. The lack of a complete genome sequence for this newly emerged A. hydrophila genotype hampers ef...

  16. A prospective study on Aeromonas in outpatients with diarrhea in the central region of Rio Grande do Sul State

    PubMed Central

    Prediger, Karoline deCampos; Pereira, Renata da Silva; Winckler Neto, Carlos Hugo Del Priore; Santos, Roberto Christ Vianna; Fadel-Picheth, Cyntia Maria Telles; Vizzotto, Bruno Stefanello

    2012-01-01

    Aeromonas spp. were identified in five (2,7%) of 182 diarrheal stool cultures, A. caviae was predominant, resistant mainly to ampicillin and cephalotin. This is the first study showing the presence of Aeromonas spp. in diarrheal stools of outpatients in the central region of Rio Grande do Sul State, Brazil. PMID:24031914

  17. Bactericidal efficacy of elevated pH on fish pathogenic and environmental bacteria

    USGS Publications Warehouse

    Starliper, Clifford E.; Watten, Barnaby J.

    2013-01-01

    Ship ballast water is a recognized medium for transfer and introductions of nonindigenous species. There is a need for new ballast water treatment methods that effectively and safely eliminate or greatly minimize movements of these species. The present study employed laboratory methods to evaluate the bactericidal efficacy of increased pH (pH 10.0–12.0) for exposure durations of up to 72 h to kill a variety of Gram-negative and Gram-positive bacteria including fish pathogens (Aeromonas spp., Yersinia ruckeri, Edwardsiella ictaluri, Serratia liquefaciens, Carnobacterium sp.), other common aquatic-inhabitant bacteria (Serratia marcescens, Pseudomonas fluorescens, Staphylococcus sp., Bacillus sp.) and indicators listed in International Maritime Organization D2 Standards; namely, Vibrio cholera (an environmental isolate from fish), Escherichia coli and Enterococcus faecalis. Volumes of 5 N NaOH were added to tryptic soy broth to obtain desired pH adjustments. Viable cells were determined after 0, 4, 12, 24, 48, and 72 h. Initial (0 h) cell numbers ranged from 3.40 × 104 cfu/mL for Bacillus sp. to 2.44 × 107 cfu/mL for E. faecalis. The effective endpoints of pH and treatment duration necessary to realize 100% bactericidal effect varied; however, all bacteria tested were killed within 72 h at pH 12.0 or lower. The lowest parameters examined, 4 h at pH 10.0, were bactericidal to V. cholera, E. ictaluri, three of four isolates of E. coli, and (three of four) Aeromonas salmonicida subsp. salmonicida. Bactericidal effect was attained at pH 10.0 within 12 h for the other A. salmonicida subsp. salmonicida, and within 24 h for P. fluorescens, and the remaining E. coli.

  18. DNA Adenine Methyltransferase Influences the Virulence of Aeromonas hydrophila

    PubMed Central

    Erova, Tatiana E.; Pillai, Lakshmi; Fadl, Amin A.; Sha, Jian; Wang, Shaofei; Galindo, Cristi L.; Chopra, Ashok K.

    2006-01-01

    Among the various virulence factors produced by Aeromonas hydrophila, a type II secretion system (T2SS)-secreted cytotoxic enterotoxin (Act) and the T3SS are crucial in the pathogenesis of Aeromonas-associated infections. Our laboratory molecularly characterized both Act and the T3SS from a diarrheal isolate, SSU of A. hydrophila, and defined the role of some regulatory genes in modulating the biological effects of Act. In this study, we cloned, sequenced, and expressed the DNA adenine methyltransferase gene of A. hydrophila SSU (damAhSSU) in a T7 promoter-based vector system using Escherichia coli ER2566 as a host strain, which could alter the virulence potential of A. hydrophila. Recombinant Dam, designated as M.AhySSUDam, was produced as a histidine-tagged fusion protein and purified from an E. coli cell lysate using nickel affinity chromatography. The purified Dam had methyltransferase activity, based on its ability to transfer a methyl group from S-adenosyl-l-methionine to N6-methyladenine-free lambda DNA and to protect methylated lambda DNA from digestion with DpnII but not against the DpnI restriction enzyme. The dam gene was essential for the viability of the bacterium, and overproduction of Dam in A. hydrophila SSU, using an arabinose-inducible, PBAD promoter-based system, reduced the virulence of this pathogen. Specifically, overproduction of M.AhySSUDam decreased the motility of the bacterium by 58%. Likewise, the T3SS-associated cytotoxicity, as measured by the release of lactate dehydrogenase enzyme in murine macrophages infected with the Dam-overproducing strain, was diminished by 55% compared to that of a control A. hydrophila SSU strain harboring the pBAD vector alone. On the contrary, cytotoxic and hemolytic activities associated with Act as well as the protease activity in the culture supernatant of a Dam-overproducing strain were increased by 10-, 3-, and 2.4-fold, respectively, compared to those of the control A. hydrophila SSU strain. The Dam

  19. In situ structural analysis of the Yersinia enterocolitica injectisome

    PubMed Central

    Kudryashev, Mikhail; Stenta, Marco; Schmelz, Stefan; Amstutz, Marlise; Wiesand, Ulrich; Castaño-Díez, Daniel; Degiacomi, Matteo T; Münnich, Stefan; Bleck, Christopher KE; Kowal, Julia; Diepold, Andreas; Heinz, Dirk W; Dal Peraro, Matteo; Cornelis, Guy R; Stahlberg, Henning

    2013-01-01

    Injectisomes are multi-protein transmembrane machines allowing pathogenic bacteria to inject effector proteins into eukaryotic host cells, a process called type III secretion. Here we present the first three-dimensional structure of Yersinia enterocolitica and Shigella flexneri injectisomes in situ and the first structural analysis of the Yersinia injectisome. Unexpectedly, basal bodies of injectisomes inside the bacterial cells showed length variations of 20%. The in situ structures of the Y. enterocolitica and S. flexneri injectisomes had similar dimensions and were significantly longer than the isolated structures of related injectisomes. The crystal structure of the inner membrane injectisome component YscD appeared elongated compared to a homologous protein, and molecular dynamics simulations documented its elongation elasticity. The ring-shaped secretin YscC at the outer membrane was stretched by 30–40% in situ, compared to its isolated liposome-embedded conformation. We suggest that elasticity is critical for some two-membrane spanning protein complexes to cope with variations in the intermembrane distance. DOI: http://dx.doi.org/10.7554/eLife.00792.001 PMID:23908767

  20. Directional gene flow and ecological separation in Yersinia enterocolitica

    PubMed Central

    Reuter, Sandra; Corander, Jukka; de Been, Mark; Harris, Simon; Cheng, Lu; Hall, Miquette; Thomson, Nicholas R.

    2015-01-01

    Yersinia enterocolitica is a common cause of food-borne gastroenteritis worldwide. Recent work defining the phylogeny of the genus Yersinia subdivided Y. enterocolitica into six distinct phylogroups. Here, we provide detailed analyses of the evolutionary processes leading to the emergence of these phylogroups. The dominant phylogroups isolated from human infections, PG3–5, show very little diversity at the sequence level, but do present marked patterns of gain and loss of functions, including those involved in pathogenicity and metabolism, including the acquisition of phylogroup-specific O-antigen loci. We tracked gene flow across the species in the core and accessory genome, and show that the non-pathogenic PG1 strains act as a reservoir for diversity, frequently acting as donors in recombination events. Analysis of the core and accessory genome also suggested that the different Y. enterocolitica phylogroups may be ecologically separated, in contrast to the long-held belief of common shared ecological niches across the Y. enterocolitica species. PMID:28348815

  1. Rapid detection of Yersinia pestis recombinant fraction 1 capsular antigen.

    PubMed

    Tsui, Pei-Yi; Tsai, Hui-Ping; Chiao, Der-Jiang; Liu, Cheng-Che; Shyu, Rong-Hwa

    2015-09-01

    Yersinia pestis, an infectious bacterium that is a causative agent of plague, a disease which has been shown to be one of the most feared in history and which has caused millions of deaths. The capsule-like fraction 1 (F1) antigen expressed by Y. pestis is a known specific marker for the identification of the bacteria; therefore, the detection of F1 is important for Y. pestis recognition. In this study, a rapid, sensitive, and specific technique, the lateral flow assay (LFA), was successfully developed to detect Y. pestis by the recombinant F1 antigen. The assay that utilized an anti-F1 polyclonal antibody (Pab) to identify the bacteria was based on a double-antibody sandwich format on a nitrocellulose membrane. With the LFA method, 50 ng/ml of recombinant F1 protein and 10(5) CFU/mL of Y. pestis could be detected in less than 10 min. This assay also showed no cross-reaction with other Yersinia spp. or with some selected capsule-producing Enterobacteriaceae strains. Furthermore, detection of Y. pestis in simulated samples has been evaluated. The detection sensitivity of Y. pestis in various matrices was 10(5) CFU/mL, which was identical to that in PBS buffer. The results obtained suggest that LFA is an excellent tool for detection of Y. pestis contamination in an environment and hence can be used to monitor plague diseases when they emerge.

  2. High prevalence of pathogenic Yersinia enterocolitica in pig cheeks.

    PubMed

    Laukkanen-Ninios, Riikka; Fredriksson-Ahomaa, Maria; Maijala, Riitta; Korkeala, Hannu

    2014-10-01

    Samples from pork cuts for minced meat and cheeks from processing plants and a slaughterhouse, and modified atmosphere (MA) packaged pork from retail were studied to estimate the prevalence of pathogenic, i.e. virulence plasmid bearing, Yersinia enterocolitica and Yersinia pseudotuberculosis in pork, as well as to quantify pathogenic Y. enterocolitica in pork cuts. Pathogenic (virF-positive) Y. enterocolitica was isolated from 17 pig cheeks (23%) but not from any of the MA-packaged 54 retail pork samples and only from one of the 155 pork cut (0.6%). Most (16/17) of the cheek samples were contaminated with pathogenic Y. enterocolitica 4/O:3 and one with bioserotype 2/O:9. No Y. pseudotuberculosis was isolated. The prevalence of pathogenic Y. enterocolitica was clearly higher (39%) in 155 pork cuts when studied with nested PCR targeting yadA on the virulence plasmid pYV although the contamination level was low varying between 0.1 and 1.6 MPN/g. Raw pork cuts and especially pig cheeks may serve as possible sources for yersiniosis caused by pathogenic Y. enterocolitica.

  3. A Molecular Study on the Prevalence and Virulence Potential of Aeromonas spp. Recovered from Patients Suffering from Diarrhea in Israel

    PubMed Central

    Senderovich, Yigal; Ken-Dror, Shifra; Vainblat, Irina; Blau, Dvora; Izhaki, Ido; Halpern, Malka

    2012-01-01

    Background Species of the genus Aeromonas are native inhabitants of aquatic environments and have recently been considered emerging human pathogens. Although the gastrointestinal tract is by far the most common anatomic site from which aeromonads are recovered, their role as etiologic agents of bacterial diarrhea is still disputed. Aeromonas-associated diarrhea is a phenomenon occurring worldwide; however, the exact prevalence of Aeromonas infections on a global scale is unknown. Methodology/Principal Findings The prevalence and virulence potential of Aeromonas in patients suffering from diarrhea in Israel was studied using molecular methods. 1,033 diarrheal stools were sampled between April and September 2010 and Aeromonas species were identified in 17 (∼2%) patients by sequencing the rpoD gene. Aeromonas species identity and abundance was: A. caviae (65%), A. veronii (29%) and Aeromonas taiwanensis (6%). This is the first clinical record of A. taiwanensis as a diarrheal causative since its recent discovery from a wound infection in a patient in Taiwan. Most of the patients (77%) from which Aeromonas species were isolated were negative for any other pathogens. The patients ranged from 1 to 92 years in age. Aeromonas isolates were found to possess different virulence-associated genes: ahpB (88%), pla/lip/lipH3/apl-1 (71%), act/hlyA/aerA (35%), alt (18%), ast (6%), fla (65%), lafA (41%), TTSS ascV (12%), TTSS ascF-ascG (12%), TTSS-dependent ADP-ribosylating toxins aexU (41%) and aexT (6%) in various combinations. Most of the identified strains were resistant to beta-lactam antibiotics but susceptible to third-generation cephalosporin antibiotics. Conclusions Aeromonas may be a causative agent of diarrhea in patients in Israel and therefore should be included in routine bacteriological screenings. PMID:22355306

  4. Maturation pathway of metalloprotease produced by Aeromonas sobria.

    PubMed

    Takahashi, Eizo; Fujii, Yoshio; Kobayashi, Hidetomo; Yamanaka, Hiroyasu; Nair, Gopinath Balakrish; Takeda, Yoshifumi; Arimoto, Sakae; Negishi, Tomoe; Okamoto, Keinosuke

    2010-10-01

    Previously, we cloned the metalloprotease gene of Aeromonas sobria (amp) and determined its nucleotide sequence (GenBank accession number DQ784565). The protease is composed of 591 amino acid residues. In this study, we purified the mature metalloprotease from the culture supernatant of A. sobria and determined the amino terminal sequence and molecular size of AMP. In addition, we examined the production of AMP diachronically and found that AMP emerges outside of the cell as an intermediate composed of mature and propeptide regions. Subsequently, we determined that the N-terminal amino acid sequence of the intermediate and found that the sequence is identical to that of the mature metalloprotease. This means that the intermediate is composed of a mature AMP region and a C-terminal propeptide. The cross culture experiment of mutants of metalloprotease and serine protease of A. sobria on skim milk agar medium indicates that the intermediate released outside of the cell is inactive and that serine protease produced by A. sobria accelerates the conversion of the intermediate from the inactive to the active form.

  5. Aeromonas hydrophila flagella glycosylation: involvement of a lipid carrier.

    PubMed

    Merino, Susana; Fulton, Kelly M; Twine, Susan M; Wilhelms, Markus; Molero, Raquel; Tomás, Juan M

    2014-01-01

    Polar flagellin proteins from Aeromonas hydrophila strain AH-3 (serotype O34) were found to be O-glycosylated with a heterogeneous glycan. Mutants unable to produce WecP or Gne enzymes showed altered motility, and the study of their polar flagellin glycosylation showed that the patterns of glycosylation differed from that observed with wild type polar flagellin. This suggested the involvement of a lipid carrier in glycosylation. A gene coding for an enzyme linking sugar to a lipid carrier was identified in strain AH-3 (WecX) and subsequent mutation abolished completely motility, flagella production by EM, and flagellin glycosylation. This is the first report of a lipid carrier involved in flagella O-glycosylation. A molecular model has been proposed. The results obtained suggested that the N-acetylhexosamines are N-acetylgalactosamines and that the heptasaccharide is completely independent of the O34-antigen lipopolysaccharide. Furthermore, by comparing the mutants with differing degrees of polar flagellin glycosylation, we established their importance in A. hydrophila flagella formation and motility.

  6. Physiological control of amonabactin biosynthesis in Aeromonas hydrophila.

    PubMed

    Barghouthi, S; Young, R; Arceneaux, J E; Byers, B R

    1989-01-01

    Amonabactin is a siderophore from Aeromonas hydrophila which is produced in two biologically active forms composed of the phenolate 2,3-dihydroxybenzoic acid (DHB), lysine, glycine, and either trytophan (amonabactin T) or phenylalanine (amonabactin P). Amonabactin biosynthetic mutants (generated by chemical mutagenesis) that either produced no amonabactin or overproduced the siderophore were isolated and identified on chrome azurol S siderophore detection agar. Amonabactin-negative mutants were of two categories. One type produced no phenolates and used exogenous DHB to synthesize amonabactin (both forms) while the other type excreted DHB but not amonabactin. This suggests an amonabactin biosynthetic pathway composed of two segments, one producing DHB and the other assembling amonabactin from DHB and the amino acids. Overproduction mutants used amonabactin poorly or not at all, indicating that they contained lesions in amonabactin utilization. Adding the analog D-tryptophan to wild-type A. hydrophila cultures reduced synthesis of both amonabactin T and amonabactin P and lengthened the lag phase in iron restricted medium. The tryptophan and phenylalanine forms of amonabactin may be synthesized by a single assembly pathway that contains a novel enzyme (sensitive to D-tryptophan) which inserts either tryptophan or phenylalanine into amonabactin.

  7. Enterobacter asburiae and Aeromonas hydrophila: soft tissue infection requiring debridement.

    PubMed

    Koth, Kevin; Boniface, James; Chance, Elisha A; Hanes, Marina C

    2012-06-01

    Enterobacter asburiae and Aeromonas hydrophila are gram-negative bacilli that have been isolated in soil and water. Enterobacter asburiae can cause an array of diseases, and exposure to A hydrophila can cause soft tissue infections, including necrotizing faciitis.A healthy-appearing 22-year-old man presented with an innocuous soft tissue injury to his leg due to an all-terrain vehicle crash. He received intravenous antibiotics and was discharged with prophylactic oral antibiotics. After the rapid onset of high fevers (102°F-103°F) <24 hours postinjury, he returned to the emergency department. Emergent surgical debridement was performed, and broad-spectrum intravenous antibiotics were started. Fevers persisted, and the patient underwent repeat extensive surgical debridement and antibiotic bead placement <30 hours after the initial surgical debridement and broad-spectrum antibiotics. Intraoperative cultures found E asburiae and A hydrophila in the wound. Following a long course of antibiotics and a skin graft, he fully recovered and had no functional deficits 1 year postoperatively.Extensive research revealed that these organisms are rare in soft tissue infections. E asburiae is opportunistic but has not been reported as a primary wound organism, and A hydrophila infections have been reported following motor vehicle crashes involving wound contamination. At presentation, it is challenging to determine rare organisms in a timely fashion; however, emergent extensive surgical intervention of an accelerated aberrant disease process should be considered to avoid catastrophic outcomes.

  8. 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

  9. Redefining the differences in gene content between Yersinia pestis and Yersinia pseudotuberculosis using large-scale comparative genomics

    PubMed Central

    Califf, Katy J.; Keim, Paul S.; Wagner, David M.

    2015-01-01

    Yersinia pestis, the causative agent of plague, is best known for historical pandemics, but still actively causes disease in many parts of the world. Y. pestis is a recently derived clone of the pathogenic species Yersinia pseudotuberculosis, but is more associated with human infection. Numerous studies have documented genomic changes since the two species differentiated, although all of these studies used a relatively small sample set for defining these differences. In this study, we compared the complete genomic content between a diverse set of Y. pestis and Y. pseudotuberculosis genomes, and identified unique loci that could serve as diagnostic markers or for better understanding the evolution and pathogenesis of each group. Comparative genomics analyses also identified subtle variations in gene content between individual monophyletic clades within these species, based on a core genome single nucleotide polymorphism phylogeny that would have been undetected in a less comprehensive genome dataset. We also screened loci that were identified in other published studies as unique to either species and generally found a non-uniform distribution, suggesting that the assignment of these unique genes to either species should be re-evaluated in the context of current sequencing efforts. Overall, this study provides a high-resolution view into the genomic differences between Y. pestis and Y. pseudotuberculosis, demonstrating fine-scale differentiation and unique gene composition in both species. PMID:28348813

  10. Yersinia-flea interactions and the evolution of the arthropod-borne transmission route of plague

    PubMed Central

    Chouikha, Iman; Hinnebusch, B. Joseph

    2012-01-01

    Yersinia pestis, the causative agent of plague, is unique among the enteric group of Gram-negative bacteria in relying on a blood-feeding insect for transmission. The Yersinia-flea interactions that enable plague transmission cycles have had profound historical consequences as manifested by human plague pandemics. The arthropod-borne transmission route was a radical ecologic change from the food- and water-borne transmission route of Yersinia pseudotuberculosis, from which Y. pestis diverged only within the last 20,000 years. Thus, the interactions of Y. pestis with its flea vector that lead to colonization and successful transmission are the result of a recent evolutionary adaptation that required relatively few genetic changes. These changes from the Y. pseudotuberculosis progenitor included loss of insecticidal activity, increased resistance to antibacterial factors in the flea midgut, and extending Yersinia biofilm-forming ability to the flea host environment. PMID:22406208

  11. Isolation of Yersinia enterocolitica biotype 4 serotype O3 from canine sources in Italy.

    PubMed Central

    Fantasia, M; Grazia Mingrone, M; Crotti, D; Boscato, C

    1985-01-01

    Seventeen strains of Yersinia enterocolitica biotype 4 serotype O3 were isolated from 63 apparently healthy puppies. Of these strains, 76.4% showed both multiple resistance to antimicrobial agents and lack of sorbose fermentation. PMID:4031044

  12. Unique activity spectrum of colicin FY: all 110 characterized Yersinia enterocolitica isolates were colicin FY susceptible.

    PubMed

    Bosák, Juraj; Micenková, Lenka; Vrba, Martin; Ševčíková, Alena; Dědičová, Daniela; Garzetti, Debora; Šmajs, David

    2013-01-01

    Colicin FY is a plasmid encoded toxin that recognizes a yersinia-specific outer membrane protein (YiuR) as a receptor molecule. We have previously shown that the activity spectrum of colicin FY comprises strains of the genus Yersinia. In this study, we analyzed the activity of colicin FY against 110 Yersinia enterocolitica isolates differing in geographical origin and source. All isolates were characterized through analysis of 16S rRNA genes, serotyping, biotyping, restriction profiling of genomic DNA, detection of virulence markers and susceptibility to antibiotics. This confirmed the broad variability of the collection, in which all 110 Y. enterocolitica isolates, representing 77 various strains, were inhibited by colicin FY. Although isolates showed variable levels of susceptibility to colicin FY, it was not associated with any strain characteristic. The universal susceptibility of Y. enterocolitica strains to colicin FY together with the absence of activity towards strains outside the Yersinia genus suggests potential therapeutic applications for colicin FY.

  13. Early Divergent Strains of Yersinia pestis in Eurasia 5,000 Years Ago

    PubMed Central

    Rasmussen, Simon; Allentoft, Morten Erik; Nielsen, Kasper; Orlando, Ludovic; Sikora, Martin; Sjögren, Karl-Göran; Pedersen, Anders Gorm; Schubert, Mikkel; Van Dam, Alex; Kapel, Christian Moliin Outzen; Nielsen, Henrik Bjørn; Brunak, Søren; Avetisyan, Pavel; Epimakhov, Andrey; Khalyapin, Mikhail Viktorovich; Gnuni, Artak; Kriiska, Aivar; Lasak, Irena; Metspalu, Mait; Moiseyev, Vyacheslav; Gromov, Andrei; Pokutta, Dalia; Saag, Lehti; Varul, Liivi; Yepiskoposyan, Levon; Sicheritz-Pontén, Thomas; Foley, Robert A.; Lahr, Marta Mirazón; Nielsen, Rasmus; Kristiansen, Kristian; Willerslev, Eske

    2015-01-01

    Summary The bacteria Yersinia pestis is the etiological agent of plague and has caused human pandemics with millions of deaths in historic times. How and when it originated remains contentious. Here, we report the oldest direct evidence of Yersinia pestis identified by ancient DNA in human teeth from Asia and Europe dating from 2,800 to 5,000 years ago. By sequencing the genomes, we find that these ancient plague strains are basal to all known Yersinia pestis. We find the origins of the Yersinia pestis lineage to be at least two times older than previous estimates. We also identify a temporal sequence of genetic changes that lead to increased virulence and the emergence of the bubonic plague. Our results show that plague infection was endemic in the human populations of Eurasia at least 3,000 years before any historical recordings of pandemics. PMID:26496604

  14. Isolation, Enumeration, and Characterization of Aeromonas from Polluted Waters Encountered in Diving Operations

    PubMed Central

    Seidler, Ramon J.; Allen, D. A.; Lockman, H.; Colwell, R. R.; Joseph, S. W.; Daily, O. P.

    1980-01-01

    Counts of total viable, aerobic, heterotrophic bacteria, indicator organisms, and Aeromonas spp. were made at a diver training site on the Anacostia River in Washington, D.C. The numbers of Aeromonas cells in Anacostia River sediment and water increased during periods of elevated water temperature, to maxima of 4 × 105 cells per g of sediment and 300 cells per ml of water. Correspondingly, Aeromonas counts dropped 2 to 4 logs as the water temperature decreased to 0 to 0.5°C. Cultures taken by sterile swabs from the ears and face masks of divers after a 30-min swim in the Anacostia River yielded bacterial types and numbers similar to those found in the river. The nasal passages of the divers apparently did not become contaminated by swimming, possibly because of the protective effect of the face masks used by the divers. Properties associated with virulence in Aeromonas hydrophila and Aeromonas sobria strains isolated from the river, sediment, and divers were investigated. Nearly 40% of the strains of both species collected during the study produced cytotoxic activity for mouse Y-1 adrenal cells, as well as elastase. Enterotoxin activity, as detected by the Y-1 assay, was observed in 3% (1 of 35) of the strains of A. sobria and in 6% (19 of 330) of the A. hydrophila strains. Fluid accumulation in rabbit ileal loops induced by both species of Aeromonas varied greatly among the 17 strains examined. Fluid accumulation of at least 0.4 ml/cm was correlated with positive cytotoxin- or enterotoxin-like response in the Y-1 tissue culture assay. PMID:7396482

  15. Isolation, enumeration, and characterization of Aeromonas from polluted waters encountered in diving operations.

    PubMed

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

    1980-05-01

    Counts of total viable, aerobic, heterotrophic bacteria, indicator organisms, and Aeromonas spp. were made at a diver training site on the Anacostia River in Washington, D.C. The numbers of Aeromonas cells in Anacostia River sediment and water increased during periods of elevated water temperature, to maxima of 4 x 10(5) cells per g of sediment and 300 cells per ml of water. Correspondingly, Aeromonas counts dropped 2 to 4 logs as the water temperature decreased to 0 to 0.5 degrees C. Cultures taken by sterile swabs from the ears and face masks of divers after a 30-min swim in the Anacostia River yielded bacterial types and numbers similar to those found in the river. The nasal passages of the divers apparently did not become contaminated by swimming, possibly because of the protective effect of the face masks used by the divers. Properties associated with virulence in Aeromonas hydrophila and Aeromonas sobria strains isolated from the river, sediment, and divers were investigated. Nearly 40% of the strains of both species collected during the study produced cytotoxic activity for mouse Y-1 adrenal cells, as well as elastase. Enterotoxin activity, as detected by the Y-1 assay, was observed in 3% (1 of 35) of the strains of A. sobria and in 6% (19 of 330) of the A. hydrophila strains. Fluid accumulation in rabbit ileal loops induced by both species of Aeromonas varied greatly among the 17 strains examined. Fluid accumulation of at least 0.4 ml/cm was correlated with positive cytotoxin- or enterotoxin-like response in the Y-1 tissue culture assay.

  16. Levels of enzymes in leukaemic mice treated withAeromonas L-asparaginase.

    PubMed

    Benny, P J; Muraleedhara Kurup, G; Sreejith, K

    1999-07-01

    L-asparaginase isolated in our laboratory fromAeromonas has been found to be antileukaemic. In the present study changes in the levels of serum enzymes in leukaemic mice and under treatment withAeromonas L-asparaginase has been compared. A significant increase in the levels of serum lactate dehydrogenase with tumour growth and a decrease during therapy was observed. A significant decrease in alanine transaminase activity during tumour growth and an increase during treatment was noticed. Increased levels of aspartate transaminase and alkaline phosphatase was observed during enzyme therapy. Total acid phosphatase was found to be increased during tumour growth and decreased considerably during treatment.

  17. Metabolism of proteins and glycoproteins in tumour bearing mice treated with Aeromonas L-asparaginase.

    PubMed

    Benny, P J; Muraleedhara, K G; Sreejith, K; Jayashree, G

    1996-12-01

    L-asparaginase, isolated in our laboratory, from Aeromonas had been found to be antileukaemic. In the present study, changes in the levels of proteins and glycoproteins in leukaemic mice and under treatment with Aeromonas L-asparaginase have been compared. Levels of protein bound hexose, fucose and sialic acid which were increased during leukaemia attained normal levels when treated with L-asparaginase. The increased blood urea level declined significantly during enzyme therapy. Effects of L-asparaginase are compared with 'Leunase', a commercially available drug used in the treatment of leukaemia.

  18. Trends of the major porin gene (ompF) evolution: insight from the genus Yersinia.

    PubMed

    Stenkova, Anna M; Isaeva, Marina P; Shubin, Felix N; Rasskazov, Valeri A; Rakin, Alexander V

    2011-01-01

    OmpF is one of the major general porins of Enterobacteriaceae that belongs to the first line of bacterial defense and interactions with the biotic as well as abiotic environments. Porins are surface exposed and their structures strongly reflect the history of multiple interactions with the environmental challenges. Unfortunately, little is known on diversity of porin genes of Enterobacteriaceae and the genus Yersinia especially. We analyzed the sequences of the ompF gene from 73 Yersinia strains covering 14 known species. The phylogenetic analysis placed most of the Yersinia strains in the same line assigned by 16S rDNA-gyrB tree. Very high congruence in the tree topologies was observed for Y. enterocolitica, Y. kristensenii, Y. ruckeri, indicating that intragenic recombination in these species had no effect on the ompF gene. A significant level of intra- and interspecies recombination was found for Y. aleksiciae, Y. intermedia and Y. mollaretii. Our analysis shows that the ompF gene of Yersinia has evolved with nonrandom mutational rate under purifying selection. However, several surface loops in the OmpF porin contain positively selected sites, which very likely reflect adaptive diversification Yersinia to their ecological niches. To our knowledge, this is a first investigation of diversity of the porin gene covering the whole genus of the family Enterobacteriaceae. This study demonstrates that recombination and positive selection both contribute to evolution of ompF, but the relative contribution of these evolutionary forces are different among Yersinia species.

  19. Canis lupus familiaris involved in the transmission of pathogenic Yersinia spp. in China.

    PubMed

    Wang, Xin; Liang, Junrong; Xi, Jinxiao; Yang, Jinchuan; Wang, Mingliu; Tian, Kecheng; Li, Jicheng; Qiu, Haiyan; Xiao, Yuchun; Duan, Ran; Yang, Haoshu; Li, Kewei; Cui, Zhigang; Qi, Meiying; Jing, Huaiqi

    2014-08-06

    To investigate canines carrying pathogens associated with human illness, we studied their roles in transmitting and maintaining pathogenic Yersinia spp. We examined different ecological landscapes in China for the distribution of pathogenic Yersinia spp. in Canis lupus familiaris, the domestic dog. The highest number of pathogenic Yersinia enterocolitica was shown from the tonsils (6.30%), followed by rectal swabs (3.63%) and feces (1.23%). Strains isolated from plague free areas for C. lupus familiaris, local pig and diarrhea patients shared the same pulsed-field gel electrophoresis (PFGE) pattern, indicating they may be from the same clone and the close transmission source of pathogenic Y. enterocolitica infections in these areas. Among 226 dogs serum samples collected from natural plague areas of Yersinia pestis in Gansu and Qinghai Provinces, 49 were positive for F1 antibody, while the serum samples collected from plague free areas were all negative, suggested a potential public health risk following exposure to dogs. No Y. enterocolitica or Yersinia pseudotuberculosis was isolated from canine rectal swabs in natural plague areas. Therefore, pathogenic Yersinia spp. may be regionally distributed in China.

  20. Differentiation of Yersinia enterocolitica biotype 1A from pathogenic Yersinia enterocolitica biotypes by detection of β-glucosidase activity: comparison of two chromogenic culture media and Vitek2.

    PubMed

    Karhukorpi, Jari; Päivänurmi, Marjut

    2014-01-01

    Aesculin hydrolysis (ESC) is one of the key reactions in differentiating pathogenic Yersinia enterocolitica biotypes 1B, 2, 3, 4 and 5 from the less-pathogenic biotype 1A. Because the ESC reaction is caused by β-glucosidase (βGLU) activity of the bacteria, we studied whether two commonly used methods (BBL CHROMagar Orientation and Vitek2 Gram-negative identification card) could be used in assessing βGLU activity of 74 Yersinia strains. Both methods were sensitive (100 % and 97 %) and specific (100 % and 100 %) in differentiating βGLU-positive YE BT1A from βGLU-negative Y. enterocolitica biotypes. For a subset of strains (n = 69), a new selective CHROMagar Yersinia showed excellent agreement with the strains' βGLU activity. Thus all the methods evaluated in this study may be used to differentiate between YE BT1A and other Y. enterocolitica biotypes.

  1. Yersinia pseudotuberculosis septicemia in a beaver from Washington State.

    PubMed

    Gaydos, Joseph K; Zabek, Erin; Raverty, Stephen

    2009-10-01

    An emaciated, free-ranging, sub-adult, male beaver (Castor canadensis) was found dead and was necropsied. Microscopically, the beaver had acute necrotizing hepatitis and splenitis with florid lobulated colonies of extracellular coccobacilli. Intravascular septic emboli were identified in lung, small intestine, and kidney, and discrete ulcers with scattered superficial extracellular accumulation of coccobacilli were noted on tail margins and plantar surfaces of the hind feet. Yersinia pseudotuberculosis was cultured on Columbia blood and MacConkey agar and identified by API 20E. Based on the pathology and acute mortality described in this case, as well as historical reports of Y. pseudotuberculosis related mortality in other beavers, this species could serve as a public health sentinel for localized occurrences of this bacterium.

  2. Protocol for Detection of Yersinia pestis in Environmental ...

    EPA Pesticide Factsheets

    Methods Report This is the first ever open-access and detailed protocol available to all government departments and agencies, and their contractors to detect Yersinia pestis, the pathogen that causes plague, from multiple environmental sample types including water. Each analytical method includes sample processing procedure for each sample type in a step-by-step manner. It includes real-time PCR, traditional microbiological culture, and the Rapid Viability PCR (RV-PCR) analytical methods. For large volume water samples it also includes an ultra-filtration-based sample concentration procedure. Because of such a non-restrictive availability of this protocol to all government departments and agencies, and their contractors, the nation will now have increased laboratory capacity to analyze large number of samples during a wide-area plague incident.

  3. Pneumonic Plague: The Darker Side of Yersinia pestis.

    PubMed

    Pechous, Roger D; Sivaraman, Vijay; Stasulli, Nikolas M; Goldman, William E

    2016-03-01

    Inhalation of the bacterium Yersinia pestis results in primary pneumonic plague. Pneumonic plague is the most severe manifestation of plague, with mortality rates approaching 100% in the absence of treatment. Its rapid disease progression, lethality, and ability to be transmitted via aerosol have compounded fears of the intentional release of Y. pestis as a biological weapon. Importantly, recent epidemics of plague have highlighted a significant role for pneumonic plague during outbreaks of Y. pestis infections. In this review we describe the characteristics of pneumonic plague, focusing on its disease progression and pathogenesis. The rapid time-course, severity, and difficulty of treating pneumonic plague highlight how differences in the route of disease transmission can enhance the lethality of an already deadly pathogen.

  4. Yersinia enterocolitica Infection Simulating Lymphoproliferative Disease, after Liver Transplant

    PubMed Central

    Jakobovich, E.; Koplewitz, B.; Marva, E.; Granot, E.

    2014-01-01

    We describe a 14-year-old girl, who was 13 y after liver transplantation for biliary atresia with an unremarkable postoperative course. She presented with fever of up to 40°C, extreme fatigue, malaise, anorexia, and occasional vomiting. On physical examination the only finding was splenomegaly. Lab results showed hyperglobulinemia and an elevated sedimentation rate. Liver function tests were normal except for mild elevation of γGTP. Abdominal U/S and CT demonstrated an enlarged spleen with retroperitoneal and mesenteric lymph nodes enlargement. An exhaustive evaluation for infectious causes, autoimmune conditions, and malignancy was negative. A full recovery after 5 months prompted testing for self-limited infectious etiologies. Yersinia enterocolitica infection was diagnosed. PMID:25126442

  5. Investigating the ?Trojan Horse? Mechanism of Yersinia pestis Virulence

    SciTech Connect

    McCutchen-Maloney, S L; Fitch, J P

    2005-02-08

    Yersinia pestis, the etiological agent of plague, is a Gram-negative, highly communicable, enteric bacterium that has been responsible for three historic plague pandemics. Currently, several thousand cases of plague are reported worldwide annually, and Y. pestis remains a considerable threat from a biodefense perspective. Y. pestis infection can manifest in three forms: bubonic, septicemic, and pneumonic plague. Of these three forms, pneumonic plague has the highest fatality rate ({approx}100% if left untreated), the shortest intervention time ({approx}24 hours), and is highly contagious. Currently, there are no rapid, widely available vaccines for plague and though plague may be treated with antibiotics, the emergence of both naturally occurring and potentially engineered antibiotic resistant strains makes the search for more effective therapies and vaccines for plague of pressing concern. The virulence mechanism of this deadly bacterium involves induction of a Type III secretion system, a syringe-like apparatus that facilitates the injection of virulence factors, termed Yersinia outer membrane proteins (Yops), into the host cell. These virulence factors inhibit phagocytosis and cytokine secretion, and trigger apoptosis of the host cell. Y. pestis virulence factors and the Type III secretion system are induced thermally, when the bacterium enters the mammalian host from the flea vector, and through host cell contact (or conditions of low Ca{sup 2+} in vitro). Apart from the temperature increase from 26 C to 37 C and host cell contact (or low Ca{sup 2+} conditions), other molecular mechanisms that influence virulence induction in Y. pestis are largely uncharacterized. This project focused on characterizing two novel mechanisms that regulate virulence factor induction in Y. pestis, immunoglobulin G (IgG) binding and quorum sensing, using a real-time reporter system to monitor induction of virulence. Incorporating a better understanding of the mechanisms of virulence

  6. A bibliography of literature pertaining to plague (Yersinia pestis)

    USGS Publications Warehouse

    Ellison, Laura E.; Frank, Megan K. Eberhardt

    2011-01-01

    Plague is an acute and often fatal zoonotic disease caused by the bacterium Yersinia pestis. Y. pestis mainly cycles between small mammals and their fleas; however, it has the potential to infect humans and frequently causes fatalities if left untreated. It is often considered a disease of the past; however, since the late 1800s, plagueis geographic range has expanded greatly, posing new threats in previously unaffected regions of the world, including the Western United States. A literature search was conducted using Internet resources and databases. The keywords chosen for the searches included plague, Yersinia pestis, management, control, wildlife, prairie dogs, fleas, North America, and mammals. Keywords were used alone or in combination with the other terms. Although this search pertains mostly to North America, citations were included from the international research community, as well. Databases and search engines used included Google (http://www.google.com), Google Scholar (http://scholar.google.com), SciVerse Scopus (http://www.scopus.com), ISI Web of Knowledge (http://apps.isiknowledge.com), and the USGS Library's Digital Desktop (http://library.usgs.gov). The literature-cited sections of manuscripts obtained from keyword searches were cross-referenced to identify additional citations or gray literature that was missed by the Internet search engines. This Open-File Report, published as an Internet-accessible bibliography, is intended to be periodically updated with new citations or older references that may have been missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the audience (users) think need to be included.

  7. The Virulence Plasmid of Yersinia, an Antihost Genome

    PubMed Central

    Cornelis, Guy R.; Boland, Anne; Boyd, Aoife P.; Geuijen, Cecile; Iriarte, Maite; Neyt, Cécile; Sory, Marie-Paule; Stainier, Isabelle

    1998-01-01

    The 70-kb virulence plasmid enables Yersinia spp. (Yersinia pestis, Y. pseudotuberculosis, and Y. enterocolitica) to survive and multiply in the lymphoid tissues of their host. It encodes the Yop virulon, an integrated system allowing extracellular bacteria to disarm the cells involved in the immune response, to disrupt their communications, or even to induce their apoptosis by the injection of bacterial effector proteins. This system consists of the Yop proteins and their dedicated type III secretion apparatus, called Ysc. The Ysc apparatus is composed of some 25 proteins including a secretin. Most of the Yops fall into two groups. Some of them are the intracellular effectors (YopE, YopH, YpkA/YopO, YopP/YopJ, YopM, and YopT), while the others (YopB, YopD, and LcrV) form the translocation apparatus that is deployed at the bacterial surface to deliver the effectors into the eukaryotic cells, across their plasma membrane. Yop secretion is triggered by contact with eukaryotic cells and controlled by proteins of the virulon including YopN, TyeA, and LcrG, which are thought to form a plug complex closing the bacterial secretion channel. The proper operation of the system also requires small individual chaperones, called the Syc proteins, in the bacterial cytosol. Transcription of the genes is controlled both by temperature and by the activity of the secretion apparatus. The virulence plasmid of Y. enterocolitica and Y. pseudotuberculosis also encodes the adhesin YadA. The virulence plasmid contains some evolutionary remnants including, in Y. enterocolitica, an operon encoding resistance to arsenic compounds. PMID:9841674

  8. Pseudogene accumulation might promote the adaptive microevolution of Yersinia pestis.

    PubMed

    Tong, Zongzhong; Zhou, Dongsheng; Song, Yajun; Zhang, Ling; Pei, Decui; Han, Yanping; Pang, Xin; Li, Min; Cui, Baizhong; Wang, Jin; Guo, Zhaobiao; Qi, Zhizhen; Jin, Lixia; Zhai, Junhui; Du, Zongmin; Wang, Jun; Wang, Xiaoyi; Yu, Jun; Wang, Jian; Huang, Peitang; Yang, Huanming; Yang, Ruifu

    2005-03-01

    Plague is a natural focus-based disease, and for better understanding of this disease it is crucial to determine the molecular mechanisms of its pathogen, Yersinia pestis, for adapting to different foci. Gene inactivation, loss and acquisition are the main mechanisms that contribute to a pathogen's fitness. Determination of the whole-genome sequences of three Y. pestis strains, CO92, KIM and 91001, provided a good opportunity to probe into its genome in minute detail. Many genetic variations were found between the three strains. The present work focused on adaptive microevolutionary analysis of Y. pestis from different natural plague foci in China based on pseudogene profiles. Twenty-four mutations that led to inactivation in the corresponding genes were analysed, and a PCR-based screening method was employed to investigate the distribution of these mutations among Y. pestis isolates from different foci and also among seven strains of Yersinia pseudotuberculosis. It was found that Y. pestis isolates from the same focus had identical mutation profiles, and 260 isolates of Y. pestis were divided into eight genotypes, while Y. pseudotuberculosis harboured wild-type alleles for all the mutations. The isolates of three known biovars were grouped into distinct branches in the phylogenetic tree, which supports the proposition that biovars mediaevalis and orientalis directly arose from biovar antiqua individually. The constructed phylogenetic tree suggests that the isolates from focus B should be the oldest lineage of Y. pestis in China except for isolates from foci L and M, which might be a special lineage of Y. pestis and originated differently to the others.

  9. Virulence Factors of Aeromonas hydrophila: In the Wake of Reclassification

    PubMed Central

    Rasmussen-Ivey, Cody R.; Figueras, Maria J.; McGarey, Donald; Liles, Mark R.

    2016-01-01

    The ubiquitous “jack-of-all-trades,” Aeromonas hydrophila, is a freshwater, Gram-negative bacterial pathogen under revision in regard to its phylogenetic and functional affiliation with other aeromonads. While virulence factors are expectedly diverse across A. hydrophila strains and closely related species, our mechanistic knowledge of the vast majority of these factors is based on the molecular characterization of the strains A. hydrophila AH-3 and SSU, which were reclassified as A. piscicola AH-3 in 2009 and A. dhakensis SSU in 2013. Individually, these reclassifications raise important questions involving the applicability of previous research on A. hydrophila virulence mechanisms; however, this issue is exacerbated by a lack of genomic data on other research strains. Collectively, these changes represent a fundamental gap in the literature on A. hydrophila and confirm the necessity of biochemical, molecular, and morphological techniques in the classification of research strains that are used as a foundation for future research. This review revisits what is known about virulence in A. hydrophila and the feasibility of using comparative genomics in light of this phylogenetic revision. Conflicting data between virulence factors, secretion systems, quorum sensing, and their effect on A. hydrophila pathogenicity appears to be an artifact of inappropriate taxonomic comparisons and/or be due to the fact that these properties are strain-specific. This review audits emerging data on dominant virulence factors that are present in both A. dhakensis and A. hydrophila in order to synthesize existing data with the aim of locating where future research is needed. PMID:27610107

  10. 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.

  11. Presence of Salmonella spp., Yersinia enterocolitica, Yersinia pseudotuberculosis and Escherichia coli O157:H7 in wild boars.

    PubMed

    Sannö, A; Aspán, A; Hestvik, G; Jacobson, M

    2014-12-01

    The European wild boar populations are growing and spreading to new areas, which might constitute a threat to public health, since wild boar can harbour pathogens with the potential to cause serious illness in humans. Tonsils, ileocaecal lymph nodes and faecal samples were collected from 88 Swedish wild boars and analysed for the presence of the zoonotic pathogens Salmonella spp., Yersinia enterocolitica, Y. pseudotuberculosis and enterohaemorrhagic Escherichia coli O157:H7 (EHEC). A combination of cultivation and polymerase chain reaction (PCR) analysis was used and overall, 20% of sampled individuals tested positive for Y. enterocolitica, 20% for Y. pseudotuberculosis and 10% for Salmonella spp. A total of 41% of sampled individuals tested positive for one or more of these three pathogens. No EHEC were detected. Samples PCR-positive for Salmonella spp. were cultivated further and six isolates were obtained, belonging to Salmonella enterica subspecies enterica and subspecies diarizone. The pathogens were most commonly detected in tonsil samples.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the summer of 2009, a new strain of Aeromonas hydrophila was implicated in severe disease outbreaks in farm-raised catfish in Alabama, Arkansas and Mississippi. These outbreaks mostly afflicted large fish and resulted in considerable losses in short periods. Given the rapid onset and biosecurity ...

  13. 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...

  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. 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....

  16. VIRULENCE RELATIONSHIPS OF AEROMONAS SPECIES AS DETERMINED BY EXPOSURES TO IMMUNOCOMPROMISED MICE

    EPA Science Inventory

    Our laboratory is currently determining the virulence of opportunistic pathogens reported in treated drinking water and drinking water sources. Aeromonas hydrophila is currently on the EPA's Contaminant Candidate List (CCL) and is an example of those types of bacteria that conta...

  17. Flagellar apparatus gene sequences of Aeromonas hydrophila AL09-73 isolate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flagellar apparatus genes of recent outbreak Aeromonas hydrophila AL09-73 isolate were sequenced and characterized. Total 28 flagellar genes were identified. The sizes of the genes range from 318 to 2001 nucleotides, which potentially encode different complex flagellar proteins. At nucleotide and...

  18. Over-expression, purification and immune responses to Aeromonas hydrophila AL09-73 flagellar proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila is ubiquitous in aquatic environments worldwide and causes many diseases in fish as well as human. Recent outbreaks of aeromonad diseases in channel catfish prompted us to investigate catfish immune responses during infection of A. hydrophila. In this communication, we report ...

  19. Draft Genome Sequence of Marine-Derived Aeromonas caviae CHZ306, a Potential Chitinase Producer Strain

    PubMed Central

    Zimpel, Cristina Kraemer; Guimaraes, Ana Marcia Sa; Pessoa, Adalberto; Rivera, Irma Nelly Gutierrez

    2016-01-01

    We report here a draft genome sequence of Aeromonas caviae CHZ306, a marine-derived bacterium with the ability to hydrolyze chitin and express high levels of chitinases. The assembly resulted in 65 scaffolds with approximately 4.78 Mb. Genomic analysis revealed different genes encoding chitin-degrading enzymes that can be used for chitin derivative production. PMID:27856589

  20. 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.

  1. Draft Genome Sequence of Marine-Derived Aeromonas caviae CHZ306, a Potential Chitinase Producer Strain.

    PubMed

    Cardozo, Flávio Augusto; Zimpel, Cristina Kraemer; Guimaraes, Ana Marcia Sa; Pessoa, Adalberto; Rivera, Irma Nelly Gutierrez

    2016-11-17

    We report here a draft genome sequence of Aeromonas caviae CHZ306, a marine-derived bacterium with the ability to hydrolyze chitin and express high levels of chitinases. The assembly resulted in 65 scaffolds with approximately 4.78 Mb. Genomic analysis revealed different genes encoding chitin-degrading enzymes that can be used for chitin derivative production.

  2. 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 ...

  3. 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...

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

    PubMed

    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.

  5. 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%.

  6. 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

  7. Draft Genome Sequences of Three Aeromonas hydrophila Isolates from Catfish and Tilapia

    PubMed Central

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

    2017-01-01

    ABSTRACT Aeromonas hydrophila is a Gram-negative bacterium that is particularly adapted to freshwater environments and can cause severe infections in fish and humans. Here, we report the draft genomes of three A. hydrophila catfish and tilapia isolates. PMID:28104665

  8. Survival of Aeromonas hydrophila and Listeria monocytogenes on fresh vegetables stored under moderate vacuum.

    PubMed

    Aytac, S A; Gorris, L G

    1994-11-01

    Storage at 6.5°C under moderate vacuum effectively prevented growth of Aeromonas hydrophila on chicory endive, but had only a limited inhibitory effect on the growth of the organism on mung bean sprouts. Growth of Listeria monocytogenes on chicory endive was strongly stimulated under these conditions, whereas it was decreased on mung-bean sprouts.

  9. 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

  10. [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.

  11. 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...

  12. 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...

  13. HOST GENE CELL RESEARCH FOR DETERMINING VIRULENCE OF AEROMONAS SPP. COLLECTED FROM ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    The United States Environmental Protection Agency (USEPA) is interested in assessing health risks associated with emerging or potential waterborne pathogens. To this end, the Agency has established a Candidate Contaminant List (CCL) that includes Aeromonas hydrophila an...

  14. 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

  15. Function of 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...

  16. Detection and quantification of virulent Aeromonas hydrophila in channel catfish tissues following waterborne challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study was to understand the pathogenesis of motile aeromonas septicemia caused by virulent A. hydrophila (vAh) in channel catfish, Ictalurus punctatus. Adipose fin clipped catfish were challenged with vAh using waterborne challenge method and the distribution of vAh in catfish tissue...

  17. 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...

  18. Humoral immune response of catfish immunized with extracellular products of 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 the pathogen. Prophylactic treatment is being sought to prevent MAS. Since multiple virulence associated facto...

  19. Antibiotic susceptibility profile of Aeromonas species isolated from wastewater treatment plant.

    PubMed

    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 bla(TEM) 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.

  20. Inactivation of Yersinia pseudotuberculosis, as a surrogate for Yersinia pestis, by liquid biocides in the presence of food residue.

    PubMed

    Hilgren, J; Swanson, K M J; Diez-Gonzalez, F; Cords, B

    2009-02-01

    The efficacy of liquid biocides is influenced by surface cleanliness, treatment time, and temperature. Experiments were completed to measure the impact of these variables on the ability of commercial biocides to inactivate Yersinia pseudotuberculosis ATCC 29910, as a surrogate for Yersinia pestis, in the presence of food residues. The test organism was mixed with water, milk, flour, or egg yolk and then dried onto stainless steel coupons. Coupons were then exposed to sodium hypochlorite, acidified sodium chlorite, a quaternary ammonium compound, an iodophor, hydrogen peroxide, peroxyacetic acid, or a peroxy-fatty acid mixture, for 10 or 30 min at 10, 20, or 30 degrees C. For all biocides except the iodophor, manufacturer-recommended disinfection levels applied for 10 min at 20 degrees C resulted in 5-log reductions of the test organism dried alone or with flour. However, in the presence of whole milk or egg yolk residue, markedly higher sodium hypochlorite, peroxyacetic acid, peroxy-fatty acid mixture, quaternary ammonium compound, and iodophor concentrations were needed to achieve the 5-log reductions. Further, the quaternary ammonium compound was incapable of achieving 5-log reductions in 10 min in the presence of milk and egg yolk residues. Hydrogen peroxide and acidified sodium chlorite disinfection levels (7.5% and 2500 ppm, respectively) achieved 5-log reductions under all test conditions. These results suggest that commercial disinfectants can adequately decontaminate clean surfaces contaminated with Y. pseudotuberculosis and Y. pestis. These results also provide guidance on the feasibility of overcoming the negative influence of food residues on disinfection by adjusting biocide exposure time, temperature, and concentration.

  1. Performance of a Handheld PCR Instrument in the Detection of Bacillus anthracis, Francisella tularensis, and Yersinia pestis: Sensitivity, Specificity, and Effect of Interferents on Assay Results

    DTIC Science & Technology

    2004-12-01

    1 PERFORMANCE OF A HANDHELD PCR INSTRUMENT IN THE DETECTION OF BACILLUS ANTHRACIS, FRANCISELLA TULARENSIS, AND YERSINIA PESTIS: SENSITIVITY...fluorogenic PCR assay reagents for the detection of three biological threat agents, Bacillus anthracis (BA), Francisella tularensis (FT), and Yersinia...TITLE AND SUBTITLE Performance Of A Handheld Pcr Instrument In The Detection Of Bacillus Anthracis, Francisella Tularensis, And Yersinia Pestis

  2. Thirty-Two Complete Genome Assemblies of Nine Yersinia Species, Including Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica

    SciTech Connect

    Johnson, Shannon L.; Daligault, Hajnalka E.; Davenport, Karen W.; Jaissle, James; Frey, Kenneth G.; Ladner, Jason T.; Broomall, Stacey M.; Bishop-Lilly, Kimberly A.; Bruce, David C.; Coyne, Susan R.; Gibbons, Henry S.; Lo, Chien-Chi; Munk, A. Christine; Rosenzweig, C. Nicole; Koroleva, Galina I.; Palacios, Gustavo F.; Redden, Cassie L.; Xu, Yan; Minogue, Timothy D.; Chain, Patrick S.

    2015-04-30

    The genus Yersinia includes three human pathogens, of which Yersinia pestis is responsible for >2,000 illnesses each year. To aid in the development of detection assays as well as aid further phylogenetic elucidation, we sequenced and assembled the complete genomes of 32 strains (across 9 Yersinia species).

  3. 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

  4. The Animal Model Determines the Results of Aeromonas Virulence Factors

    PubMed Central

    Romero, Alejandro; Saraceni, Paolo R.; Merino, Susana; Figueras, Antonio; Tomás, Juan M.; Novoa, Beatriz

    2016-01-01

    The selection of an experimental animal model is of great importance in the study of bacterial virulence factors. Here, a bath infection of zebrafish larvae is proposed as an alternative model to study the virulence factors of Aeromonas hydrophila. Intraperitoneal infections in mice and trout were compared with bath infections in zebrafish larvae using specific mutants. The great advantage of this model is that bath immersion mimics the natural route of infection, and injury to the tail also provides a natural portal of entry for the bacteria. The implication of T3SS in the virulence of A. hydrophila was analyzed using the AH-1::aopB mutant. This mutant was less virulent than the wild-type strain when inoculated into zebrafish larvae, as described in other vertebrates. However, the zebrafish model exhibited slight differences in mortality kinetics only observed using invertebrate models. Infections using the mutant AH-1ΔvapA lacking the gene coding for the surface S-layer suggested that this protein was not totally necessary to the bacteria once it was inside the host, but it contributed to the inflammatory response. Only when healthy zebrafish larvae were infected did the mutant produce less mortality than the wild-type. Variations between models were evidenced using the AH-1ΔrmlB, which lacks the O-antigen lipopolysaccharide (LPS), and the AH-1ΔwahD, which lacks the O-antigen LPS and part of the LPS outer-core. Both mutants showed decreased mortality in all of the animal models, but the differences between them were only observed in injured zebrafish larvae, suggesting that residues from the LPS outer core must be important for virulence. The greatest differences were observed using the AH-1ΔFlaB-J (lacking polar flagella and unable to swim) and the AH-1::motX (non-motile but producing flagella). They were as pathogenic as the wild-type strain when injected into mice and trout, but no mortalities were registered in zebrafish larvae. This study demonstrates

  5. Survival and recovery of Aeromonas hydrophila in water: development of methodology for testing bottled water in Canada.

    PubMed

    Warburton, D W; McCormick, J K; Bowen, B

    1994-02-01

    Proposed changes to the Regulations for bottled water in the Food and Drugs Act of Canada include criteria for Aeromonas hydrophila (0 colony-forming units/100 mL water). The development of the methodology used to support these proposed Regulations and the survival of A. hydrophila in inoculated water are described. The methodology used in the isolation of A. hydrophila includes the use of hydrophobic grid membrane filters (HGMF), a resuscitation step on tryptic soy agar, and selective plating on membrane-Aeromonas-trehalose agar and Aeromonas medium. Aeromonas hydrophila proliferated and survived in inoculated water for up to 60 days or longer depending on the other contaminating bacteria. The presence of Pseudomonas aeruginosa enhanced the survival of A. hydrophila and enabled this bacteria to survive for more than 60 days.

  6. Behavior of Yersinia enterocolitica in the Presence of the Bacterivorous Acanthamoeba castellanii

    PubMed Central

    Lambrecht, E.; Baré, J.; Van Damme, I.; Bert, W.; Sabbe, K.

    2013-01-01

    Free-living protozoa play an important role in the ecology and epidemiology of human-pathogenic bacteria. In the present study, the interaction between Yersinia enterocolitica, an important food-borne pathogen, and the free-living amoeba Acanthamoeba castellanii was studied. Several cocultivation assays were set up to assess the resistance of Y. enterocolitica to A. castellanii predation and the impact of environmental factors and bacterial strain-specific characteristics. Results showed that all Y. enterocolitica strains persist in association with A. castellanii for at least 14 days, and associations with A. castellanii enhanced survival of Yersinia under nutrient-rich conditions at 25°C and under nutrient-poor conditions at 37°C. Amoebae cultivated in the supernatant of one Yersinia strain showed temperature- and time-dependent permeabilization. Intraprotozoan survival of Y. enterocolitica depended on nutrient availability and temperature, with up to 2.8 log CFU/ml bacteria displaying intracellular survival at 7°C for at least 4 days in nutrient-rich medium. Transmission electron microscopy was performed to locate the Yersinia cells inside the amoebae. As Yersinia and Acanthamoeba share similar ecological niches, this interaction identifies a role of free-living protozoa in the ecology and epidemiology of Y. enterocolitica. PMID:23934496

  7. Cold Shock Proteins: A Minireview with Special Emphasis on Csp-family of Enteropathogenic Yersinia.

    PubMed

    Keto-Timonen, Riikka; Hietala, Nina; Palonen, Eveliina; Hakakorpi, Anna; Lindström, Miia; Korkeala, Hannu

    2016-01-01

    Bacteria have evolved a number of mechanisms for coping with stress and adapting to changing environmental conditions. Many bacteria produce small cold shock proteins (Csp) as a response to rapid temperature downshift (cold shock). During cold shock, the cell membrane fluidity and enzyme activity decrease, and the efficiency of transcription and translation is reduced due to stabilization of nucleic acid secondary structures. Moreover, protein folding is inefficient and ribosome function is hampered. Csps are thought to counteract these harmful effects by serving as nucleic acid chaperons that may prevent the formation of secondary structures in mRNA at low temperature and thus facilitate the initiation of translation. However, some Csps are non-cold inducible and they are reported to be involved in various cellular processes to promote normal growth and stress adaptation responses. Csps have been shown to contribute to osmotic, oxidative, starvation, pH and ethanol stress tolerance as well as to host cell invasion. Therefore, Csps seem to have a wider role in stress tolerance of bacteria than previously assumed. Yersinia enterocolitica and Yersinia pseudotuberculosis are enteropathogens that can spread through foodstuffs and cause an enteric infection called yersiniosis. Enteropathogenic Yersinia are psychrotrophs that are able to grow at temperatures close to 0°C and thus they set great challenges for the modern food industry. To be able to efficiently control psychrotrophic Yersinia during food production and storage, it is essential to understand the functions and roles of Csps in stress response of enteropathogenic Yersinia.

  8. Cold Shock Proteins: A Minireview with Special Emphasis on Csp-family of Enteropathogenic Yersinia

    PubMed Central

    Keto-Timonen, Riikka; Hietala, Nina; Palonen, Eveliina; Hakakorpi, Anna; Lindström, Miia; Korkeala, Hannu

    2016-01-01

    Bacteria have evolved a number of mechanisms for coping with stress and adapting to changing environmental conditions. Many bacteria produce small cold shock proteins (Csp) as a response to rapid temperature downshift (cold shock). During cold shock, the cell membrane fluidity and enzyme activity decrease, and the efficiency of transcription and translation is reduced due to stabilization of nucleic acid secondary structures. Moreover, protein folding is inefficient and ribosome function is hampered. Csps are thought to counteract these harmful effects by serving as nucleic acid chaperons that may prevent the formation of secondary structures in mRNA at low temperature and thus facilitate the initiation of translation. However, some Csps are non-cold inducible and they are reported to be involved in various cellular processes to promote normal growth and stress adaptation responses. Csps have been shown to contribute to osmotic, oxidative, starvation, pH and ethanol stress tolerance as well as to host cell invasion. Therefore, Csps seem to have a wider role in stress tolerance of bacteria than previously assumed. Yersinia enterocolitica and Yersinia pseudotuberculosis are enteropathogens that can spread through foodstuffs and cause an enteric infection called yersiniosis. Enteropathogenic Yersinia are psychrotrophs that are able to grow at temperatures close to 0°C and thus they set great challenges for the modern food industry. To be able to efficiently control psychrotrophic Yersinia during food production and storage, it is essential to understand the functions and roles of Csps in stress response of enteropathogenic Yersinia. PMID:27499753

  9. Prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia species isolates in ducks and geese.

    PubMed

    Jamali, Hossein; Radmehr, Behrad; Ismail, Salmah

    2014-04-01

    The aims of this study were to determine the prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia spp. isolated from duck and goose intestinal contents. A total of 471 samples, including 291 duck and 180 goose intestinal contents, were purchased from wet markets between November 2008 and July 2010. Listeria, Salmonella, and Yersinia spp. were isolated from 58 (12.3%), 107 (22.7%), and 80 (17%) of the samples, respectively. It was concluded that Listeria ivanovii, Salmonella Thompson, and Yersinia enterocolitica were the predominant serovars among Listeria, Salmonella, and Yersinia spp., respectively. Moreover, resistance to tetracycline was common in Listeria (48.3%) and Salmonella spp. (63.6%), whereas 51.3% of the Yersinia spp. isolates were resistant to cephalothin. Therefore, continued surveillance of the prevalence of the pathogens and also of emerging antibiotic resistance is needed to render possible the recognition of foods that may represent risks and also ensure the effective treatment of listeriosis, salmonellosis, and yersiniosis.

  10. The source of Yersinia spp. in pasteurized milk: an investigation at a dairy.

    PubMed Central

    Greenwood, M. H.; Hooper, W. L.; Rodhouse, J. C.

    1990-01-01

    Pasteurized bottled milk supplied by a single dairy was frequently found to be contaminated with Yersinia spp. Investigations were carried out at the dairy in an effort to pinpoint the source of these organisms. Viable counts obtained from milk bottle rinses indicated that bottle washing was often unsatisfactory, and on one occasion Y. frederiksenii was isolated from the pooled rinse water of six bottles. Samples of milk were taken on arrival at the dairy and at various stages following pasteurization. Heat resistance tests carried out on strains of yersinia isolated from pasteurized milk indicated that they would not survive the pasteurization process. However two strains of yersinia were isolated from a sample of milk taken immediately after pasteurization but before bottling. The thermograph indicated that the time/temperature conditions applied during pasteurization were adequate. The presence of yersinia strains in the milk at this stage therefore suggests that undetectable levels of raw milk were being allowed to contaminate the pasteurized milk. The absence of yersinia in cartoned samples produced on the same day as contaminated bottled samples indicated that environmental contamination of the bottle filler valve also may have occurred at times. Results of this investigation indicate that increased vigilance is required to ensure proper operation of pasteurizers and bottle washers. PMID:2347380

  11. Evolutionary study of Yersinia genomes deciphers emergence of human pathogenic species

    PubMed Central

    Tan, Shi Yang; Tan, Irene Kit Ping; Tan, Mui Fern; Dutta, Avirup; Choo, Siew Woh

    2016-01-01

    On record, there are 17 species in the Yersinia genus, of which three are known to be pathogenic to human. While the chromosomal and pYV (or pCD1) plasmid-borne virulence genes as well as pathogenesis of these three species are well studied, their genomic evolution is poorly understood. Our study aims to predict the key evolutionary events that led to the emergence of pathogenic Yersinia species by analyzing gene gain-and-loss, virulence genes, and “Clustered regularly-interspaced short palindromic repeats”. Our results suggest that the most recent ancestor shared by the human pathogenic Yersinia was most probably an environmental species that had adapted to the human body. This might have led to ecological specialization that diverged Yersinia into ecotypes and distinct lineages based on differential gene gain-and-loss in different niches. Our data also suggest that Y. pseudotuberculosis group might be the donor of the ail virulence gene to Y. enterocolitica. Hence, we postulate that evolution of human pathogenic Yersinia might not be totally in parallel, but instead, there were lateral gene transfer events. Furthermore, the presence of virulence genes seems to be important for the positive selection of virulence plasmid. Our studies provide better insights into the evolutionary biology of these bacteria. PMID:27796355

  12. Expression and characterization of a codon-optimized alkaline-stable carbonic anhydrase from Aliivibrio salmonicida for CO2 sequestration applications.

    PubMed

    Jun, So-Young; Kim, Sung Ho; Kanth, Bashista Kumar; Lee, Jinwon; Pack, Seung Pil

    2017-03-01

    The CO2 mineralization process, accelerated by carbonic anhydrase (CA) was proposed for the efficient capture and storage of CO2, the accumulation of which in the atmosphere is the main cause of global warming. Here, we characterize a highly stable form of the cloned CA from the Gram-negative marine bacterium Aliivibrio salmonicida, named ASCA that can promote CO2 absorption in an alkaline solvent required for efficient carbon capture. We designed a mature form of ASCA (mASCA) using a codon optimization of ASCA gene and removal of ASCA signal peptide. mASCA was highly expressed (255 mg/L) with a molecular weight of approximately 26 kDa. The mASCA enzyme exhibited stable esterase activity within a temperature range of 10-60 °C and a pH range of 6-11. mASCA activity remained stable for 48 h at pH 10. We also investigated its inhibition profiles using inorganic anions, such as acetazolamide, sulfanilamide, iodide, nitrate, and azide. We also demonstrate that mASCA is capable of catalyzing the conversion of CO2 to CaCO3 (calcite form) in the presence of Ca(2+). It should be noted that mASCA enzyme exhibits high production yield and sufficient stabilities against relatively high temperature and alkaline pH, which are required conditions for the development of more efficient enzymatic CCS systems.

  13. 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

  14. Effect of temperature on growth and activity of Aeromonas spp. and mixed bacterial populations in the Anacostia River.

    PubMed Central

    Cavari, B Z; Allen, D A; Colwell, R R

    1981-01-01

    During the winter months, total bacterial counts in the water column and in the sediment in the Anacostia River were two- to eightfold higher than at other times of the year, whereas Aeromonas spp. decreased in number of several orders of magnitude. This significant decrease in number in the Anacostia River during the cold months of the year can be explained by the low metabolic activity of Aeromonas at low temperatures. PMID:7235703

  15. Effect of temperature on growth and activity of Aeromonas spp. and mixed bacterial populations in the Anacostia River.

    PubMed

    Cavari, B Z; Allen, D A; Colwell, R R

    1981-04-01

    During the winter months, total bacterial counts in the water column and in the sediment in the Anacostia River were two- to eightfold higher than at other times of the year, whereas Aeromonas spp. decreased in number of several orders of magnitude. This significant decrease in number in the Anacostia River during the cold months of the year can be explained by the low metabolic activity of Aeromonas at low temperatures.

  16. Comparative Omics-Driven Genome Annotation Refinement: Application across Yersiniae

    SciTech Connect

    Rutledge, Alexandra C.; Jones, Marcus B.; Chauhan, Sadhana; Purvine, Samuel O.; Sanford, James; Monroe, Matthew E.; Brewer, Heather M.; Payne, Samuel H.; Ansong, Charles; Frank, Bryan C.; Smith, Richard D.; Peterson, Scott; Motin, Vladimir L.; Adkins, Joshua N.

    2012-03-27

    Genome sequencing continues to be a rapidly evolving technology, yet most downstream aspects of genome annotation pipelines remain relatively stable or are even being abandoned. To date, the perceived value of manual curation for genome annotations is not offset by the real cost and time associated with the process. In order to balance the large number of sequences generated, the annotation process is now performed almost exclusively in an automated fashion for most genome sequencing projects. One possible way to reduce errors inherent to automated computational annotations is to apply data from 'omics' measurements (i.e. transcriptional and proteomic) to the un-annotated genome with a proteogenomic-based approach. This approach does require additional experimental and bioinformatics methods to include omics technologies; however, the approach is readily automatable and can benefit from rapid developments occurring in those research domains as well. The annotation process can be improved by experimental validation of transcription and translation and aid in the discovery of annotation errors. Here the concept of annotation refinement has been extended to include a comparative assessment of genomes across closely related species, as is becoming common in sequencing efforts. Transcriptomic and proteomic data derived from three highly similar pathogenic Yersiniae (Y. pestis CO92, Y. pestis pestoides F, and Y. pseudotuberculosis PB1/+) was used to demonstrate a comprehensive comparative omic-based annotation methodology. Peptide and oligo measurements experimentally validated the expression of nearly 40% of each strain's predicted proteome and revealed the identification of 28 novel and 68 previously incorrect protein-coding sequences (e.g., observed frameshifts, extended start sites, and translated pseudogenes) within the three current Yersinia genome annotations. Gene loss is presumed to play a major role in Y. pestis acquiring its niche as a virulent pathogen, thus

  17. Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii

    PubMed Central

    Tasiemski, Aurélie; Massol, François; Cuvillier-Hot, Virginie; Boidin-Wichlacz, Céline; Roger, Emmanuel; Rodet, Franck; Fournier, Isabelle; Thomas, Frédéric; Salzet, Michel

    2015-01-01

    The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, a versatile bacterium which can also display free-living waterborne and fish- or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in the dynamics of interaction between the leech and its gut symbiont Aeromonas. By combining biochemical and molecular approaches, we isolated and identified for the first time the antimicrobial peptides (AMPs) produced by the leech digestive tract and by its symbiont Aeromonas. Immunohistochemistry data and PCR analyses evidenced that leech AMP genes are induced in the gut epithelial cells when Aeromonas load is low (starved animals), while repressed when Aeromonas abundance is the highest (post blood feeding). The asynchronous production of AMPs by both partners suggests that these antibiotic substances (i) provide them with reciprocal protection against invasive bacteria and (ii) contribute to the unusual simplicity of the gut microflora of the leech. This immune benefit substantially reinforces the evidence of an evolutionarily stable association between H. verbana and A. veronii. Altogether these data may provide insights into the processes making the association with an Aeromonas species in the digestive tract either deleterious or beneficial. PMID:26635240

  18. Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii.

    PubMed

    Tasiemski, Aurélie; Massol, François; Cuvillier-Hot, Virginie; Boidin-Wichlacz, Céline; Roger, Emmanuel; Rodet, Franck; Fournier, Isabelle; Thomas, Frédéric; Salzet, Michel

    2015-12-04

    The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, a versatile bacterium which can also display free-living waterborne and fish- or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in the dynamics of interaction between the leech and its gut symbiont Aeromonas. By combining biochemical and molecular approaches, we isolated and identified for the first time the antimicrobial peptides (AMPs) produced by the leech digestive tract and by its symbiont Aeromonas. Immunohistochemistry data and PCR analyses evidenced that leech AMP genes are induced in the gut epithelial cells when Aeromonas load is low (starved animals), while repressed when Aeromonas abundance is the highest (post blood feeding). The asynchronous production of AMPs by both partners suggests that these antibiotic substances (i) provide them with reciprocal protection against invasive bacteria and (ii) contribute to the unusual simplicity of the gut microflora of the leech. This immune benefit substantially reinforces the evidence of an evolutionarily stable association between H. verbana and A. veronii. Altogether these data may provide insights into the processes making the association with an Aeromonas species in the digestive tract either deleterious or beneficial.

  19. Ciprofloxacin v placebo for treatment of Yersinia enterocolitica triggered reactive arthritis

    PubMed Central

    Hoogkamp-Korstanj..., J; Moesker, H; Bruyn, G

    2000-01-01

    Patients with yersinia triggered reactive arthritis were double blind randomly allocated to receive treatment with ciprofloxacin 500 mg twice daily orally or placebo during three months. The diagnosis was made by serology (specific IgA and IgG antibodies to yersinia outer membrane proteins (yops)), positive culture, and/or demonstration of Yersinia enterocolitica antigen in colon biopsy specimens. Patients were evaluated monthly during and after treatment up to 12 months. Of 18 patients enrolled, all could be evaluated for safety, 16 for efficacy. There was a tendency towards faster remission and relief of pain in those receiving ciprofloxacin. Y enterocolitica was eliminated from the gut associated lymphoid tissue in six of seven patients receiving ciprofloxacin compared with none of nine patients receiving placebo. Patients receiving placebo had more and prolonged circulating IgA antibodies against yops than patients treated with ciprofloxacin.

 PMID:11053072

  20. An additional step in the transmission of Yersinia pestis?

    PubMed Central

    Easterday, W Ryan; Kausrud, Kyrre L; Star, Bastiaan; Heier, Lise; Haley, Bradd J; Ageyev, Vladimir; Colwell, Rita R; Stenseth, Nils Chr

    2012-01-01

    Plague, caused by the bacterium Yersinia pestis, is a mammalian vector-borne disease, transmitted by fleas that serve as the vector between rodent hosts. For many pathogens, including Y. pestis, there are strong evolutionary pressures that lead to a reduction in ‘useless genes', with only those retained that reflect function in the specific environment inhabited by the pathogen. Genetic traits critical for survival and transmission between two environments, the rodent and the flea, are conserved in epizootic/epidemic plague strains. However, there are genes that remain conserved for which no function in the flea–rodent cycle has yet been observed, indicating an additional environment may exist in the transmission cycle of plague. Here, we present evidence for highly conserved genes that suggests a role in the persistence of Y. pestis after death of its host. Furthermore, maintenance of these genes points to Y. pestis traversing a post-mortem path between, and possibly within, epizootic periods and offering insight into mechanisms that may allow Y. pestis an alternative route of transmission in the natural environment. PMID:21833036

  1. Detection of Yersinia enterocolitica in food: an overview.

    PubMed

    Gupta, V; Gulati, P; Bhagat, N; Dhar, M S; Virdi, J S

    2015-04-01

    Yersinia enterocolitica is a gastrointestinal pathogen which causes yersiniosis, an illness characterized by diarrhea, ileitis, and mesenteric lymphadenitis. Y. enterocolitica is transmitted via the feco-oral route by the consumption of contaminated food or water. Several phenotypic and genotypic methods have been developed to reliably detect Y. enterocolitica in food. However, the source of infection of many recently reported foodborne outbreaks remains obscure. The detection of this pathogen in food is a challenging task, since it shares similarities with other enteric bacteria. The presence of other microorganisms in the food samples makes it even more difficult to identify this slow-growing pathogen. Therefore, the present-day emphasis is on the development of sensitive, easily automated methods suitable for in-situ detection, allowing quick and cost-effective characterization of food samples. This review summarizes and compares the currently available cultural, immunological, and molecular methods, particularly in relation to their specific merits or demerits when implemented for the detection of Y. enterocolitica in food.

  2. Distinct clones of Yersinia pestis caused the black death.

    PubMed

    Haensch, Stephanie; Bianucci, Raffaella; Signoli, Michel; Rajerison, Minoarisoa; Schultz, Michael; Kacki, Sacha; Vermunt, Marco; Weston, Darlene A; Hurst, Derek; Achtman, Mark; Carniel, Elisabeth; Bramanti, Barbara

    2010-10-07

    From AD 1347 to AD 1353, the Black Death killed tens of millions of people in Europe, leaving misery and devastation in its wake, with successive epidemics ravaging the continent until the 18(th) century. The etiology of this disease has remained highly controversial, ranging from claims based on genetics and the historical descriptions of symptoms that it was caused by Yersinia pestis to conclusions that it must have been caused by other pathogens. It has also been disputed whether plague had the same etiology in northern and southern Europe. Here we identified DNA and protein signatures specific for Y. pestis in human skeletons from mass graves in northern, central and southern Europe that were associated archaeologically with the Black Death and subsequent resurgences. We confirm that Y. pestis caused the Black Death and later epidemics on the entire European continent over the course of four centuries. Furthermore, on the basis of 17 single nucleotide polymorphisms plus the absence of a deletion in glpD gene, our aDNA results identified two previously unknown but related clades of Y. pestis associated with distinct medieval mass graves. These findings suggest that plague was imported to Europe on two or more occasions, each following a distinct route. These two clades are ancestral to modern isolates of Y. pestis biovars Orientalis and Medievalis. Our results clarify the etiology of the Black Death and provide a paradigm for a detailed historical reconstruction of the infection routes followed by this disease.

  3. Comparative omics-driven genome annotation refinement: application across Yersiniae.

    PubMed

    Schrimpe-Rutledge, Alexandra C; Jones, Marcus B; Chauhan, Sadhana; Purvine, Samuel O; Sanford, James A; Monroe, Matthew E; Brewer, Heather M; Payne, Samuel H; Ansong, Charles; Frank, Bryan C; Smith, Richard D; Peterson, Scott N; Motin, Vladimir L; Adkins, Joshua N

    2012-01-01

    Genome sequencing continues to be a rapidly evolving technology, yet most downstream aspects of genome annotation pipelines remain relatively stable or are even being abandoned. The annotation process is now performed almost exclusively in an automated fashion to balance the large number of sequences generated. One possible way of reducing errors inherent to automated computational annotations is to apply data from omics measurements (i.e. transcriptional and proteomic) to the un-annotated genome with a proteogenomic-based approach. Here, the concept of annotation refinement has been extended to include a comparative assessment of genomes across closely related species. Transcriptomic and proteomic data derived from highly similar pathogenic Yersiniae (Y. pestis CO92, Y. pestis Pestoides F, and Y. pseudotuberculosis PB1/+) was used to demonstrate a comprehensive comparative omic-based annotation methodology. Peptide and oligo measurements experimentally validated the expression of nearly 40% of each strain's predicted proteome and revealed the identification of 28 novel and 68 incorrect (i.e., observed frameshifts, extended start sites, and translated pseudogenes) protein-coding sequences within the three current genome annotations. Gene loss is presumed to play a major role in Y. pestis acquiring its niche as a virulent pathogen, thus the discovery of many translated pseudogenes, including the insertion-ablated argD, underscores a need for functional analyses to investigate hypotheses related to divergence. Refinements included the discovery of a seemingly essential ribosomal protein, several virulence-associated factors, a transcriptional regulator, and many hypothetical proteins that were missed during annotation.

  4. Membrane filter technique for the isolation of Yersinia enterocolitica.

    PubMed Central

    Bartley, T D; Quan, T J; Collins, M T; Morrison, S M

    1982-01-01

    A membrane filter procedure was developed for the isolation of Yersinia enterocolitica from aquatic environments. Primary differentiation was based on the fermentation of sorbitol, the absence of lysine decarboxylase and arginine decarboxylase-dihydrolase activities, and the production of urease. Sodium deoxycholate was incorporated as an inhibitor of background organisms. The presumptive identification of Y. enterocolitica was accomplished in 50 h, and the rate of identity confirmation of typical colonies was 88%. The mean recovery rate of 15 strains from phosphate buffer suspensions was 91%, and quantitative recovery was demonstrated for low populations of the organism in both laboratory-prepared and naturally occurring mixed cultures. The technique was used to isolate 33 strains of Y. enterocolitica from 15 of 27 river water samples and from prechlorinated sewage effluent. Nine (27%) of the isolates were rhamnose positive, and only five (15%) were serotypable. Two isolates were identified as serotype O:4 (or O:4,32), two were O:17, and the fifth was O:40. PMID:7081985

  5. First report: Yersinia enterocolitica recovered from canine tonsils.

    PubMed

    Murphy, Brenda P; Drummond, Niall; Ringwood, Tamara; O'Sullivan, Edmund; Buckley, James F; Whyte, Paul; Prentice, Mike B; Fanning, Séamus

    2010-12-15

    Yersinia enterocolitica (Y. enterocolitica) is a known zoonotic pathogen and is often found in pig tonsils as the primary site of colonisation. In this study we investigated whether or not Y. enterocolitica could be recovered from canine tonsils. During a study on the prevalence of Y. enterocolitica in animal populations in Ireland, 144 canine tonsils and 72 canine rectal swabs were procured over a ten-month period and subjected to microbiological examination for the presence of this human pathogen. Molecular methods were used to determine virulence and all strains were negative for the chromosomally mediated virulence factor (ail) and plasmid-encoded adhesion molecule (pYad). Y. enterocolitica was recovered from 25 of 216 (12%) samples. Twenty-four strains were from tonsils along with one from a rectal swab. All were biotype 1A. Antimicrobial resistance profiling showed two of 25 (8%) were resistant to cephalothin and the remaining strains were resistant to ampicillin and cephalothin with six of these additionally resistant to streptomycin. Our evidence that a human pathogen may be harboured in the oral cavity of dogs' adds a new dimension to the epidemiology of this organism, identifying a potential public health risk following exposure to dogs.

  6. Prevalence of Pathogenic Yersinia enterocolitica in Finnish Slaughter Pigs.

    PubMed

    Rahikainen Ibañez, T; Laukkanen-Ninios, R; Hakkinen, M; Johansson, T; Vilar, M; Korkeala, H

    2016-04-01

    The prevalence of human pathogenic Yersinia enterocolitica was determined in tonsil and intestinal content samples from 388 healthy fattening pigs at the four biggest Finnish slaughterhouses. These slaughterhouses process 73% of pigs in Finland. Tonsil samples were tested by PCR targeted for yadA, and intestinal samples were cultured. All pathogenic Y. enterocolitica isolates represented bioserotype 4/O:3. The prevalence of Y. enterocolitica in tonsil samples was 60% (95% confidence limit, 55.4 to 65.1%), and its prevalence in intestinal samples was 26% (95% confidence limit, 22.1 to 31.2%). The prevalence of Y. enterocolitica in tonsil and intestinal samples varied between the four slaughterhouses. The tonsil prevalence of Y. enterocolitica was higher in slaughterhouse B, and the prevalence in intestinal content was higher in slaughterhouse C. There were more positive results in both tonsil and intestinal samples in pigs coming from fattening farms than in pigs coming from farrowing-and-fattening farms. A seasonal variation was observed in the prevalence of Y. enterocolitica in intestinal samples, with the highest prevalence during July and August, but no seasonal variation was detected in tonsil samples.

  7. Distinct Clones of Yersinia pestis Caused the Black Death

    PubMed Central

    Haensch, Stephanie; Bianucci, Raffaella; Signoli, Michel; Rajerison, Minoarisoa; Schultz, Michael; Kacki, Sacha; Vermunt, Marco; Weston, Darlene A.; Hurst, Derek; Achtman, Mark; Carniel, Elisabeth; Bramanti, Barbara

    2010-01-01

    From AD 1347 to AD 1353, the Black Death killed tens of millions of people in Europe, leaving misery and devastation in its wake, with successive epidemics ravaging the continent until the 18th century. The etiology of this disease has remained highly controversial, ranging from claims based on genetics and the historical descriptions of symptoms that it was caused by Yersinia pestis to conclusions that it must have been caused by other pathogens. It has also been disputed whether plague had the same etiology in northern and southern Europe. Here we identified DNA and protein signatures specific for Y. pestis in human skeletons from mass graves in northern, central and southern Europe that were associated archaeologically with the Black Death and subsequent resurgences. We confirm that Y. pestis caused the Black Death and later epidemics on the entire European continent over the course of four centuries. Furthermore, on the basis of 17 single nucleotide polymorphisms plus the absence of a deletion in glpD gene, our aDNA results identified two previously unknown but related clades of Y. pestis associated with distinct medieval mass graves. These findings suggest that plague was imported to Europe on two or more occasions, each following a distinct route. These two clades are ancestral to modern isolates of Y. pestis biovars Orientalis and Medievalis. Our results clarify the etiology of the Black Death and provide a paradigm for a detailed historical reconstruction of the infection routes followed by this disease. PMID:20949072

  8. Long-Term Persistence of Yersinia pseudotuberculosis in Entomopathogenic Nematodes

    PubMed Central

    Gengler, Samuel; Laudisoit, Anne; Batoko, Henri; Wattiau, Pierre

    2015-01-01

    Entomopathogenic nematodes (EPNs) are small worms whose ecological behaviour consists to invade, kill insects and feed on their cadavers thanks to a species-specific symbiotic bacterium belonging to any of the genera Xenorhabdus or Photorhabdus hosted in the gastro-intestinal tract of EPNs. The symbiont provides a number of biological functions that are essential for its EPN host including the production of entomotoxins, of enzymes able to degrade the insect constitutive macromolecules and of antimicrobial compounds able to prevent the growth of competitors in the insect cadaver. The question addressed in this study was to investigate whether a mammalian pathogen taxonomically related to Xenorhabdus was able to substitute for or “hijack” the symbiotic relationship associating Xenorhabdus and Steinernema EPNs. To deal with this question, a laboratory experimental model was developed consisting in Galleria mellonella insect larvae, Steinernema EPNs with or without their natural Xenorhabdus symbiont and Yersinia pseudotuberculosis brought artificially either in the gut of EPNs or in the haemocoel of the insect larva prior to infection. The developed model demonstrated the capacity of EPNs to act as an efficient reservoir ensuring exponential multiplication, maintenance and dissemination of Y. pseudotuberculosis. PMID:25635766

  9. Transcriptome Changes Associated with Anaerobic Growth in Yersinia intermedia (ATCC29909)

    PubMed Central

    Kiley, Patricia J.; Glasner, Jeremy D.; Perna, Nicole T.

    2013-01-01

    Background The yersiniae (Enterobacteriaceae) occupy a variety of niches, including some in human and flea hosts. Metabolic adaptations of the yersiniae, which contribute to their success in these specialized environments, remain largely unknown. We report results of an investigation of the transcriptome under aerobic and anaerobic conditions for Y. intermedia, a non-pathogenic member of the genus that has been used as a research surrogate for Y. pestis. Y. intermedia shares characteristics of pathogenic yersiniae, but is not known to cause disease in humans. Oxygen restriction is an important environmental stimulus experienced by many bacteria during their life-cycles and greatly influences their survival in specific environments. How oxygen availability affects physiology in the yersiniae is of importance in their life cycles but has not been extensively characterized. Methodology/Principal Findings Tiled oligonucleotide arrays based on a draft genome sequence of Y. intermedia were used in transcript profiling experiments to identify genes that change expression in response to oxygen availability during growth in minimal media with glucose. The expression of more than 400 genes, constituting about 10% of the genome, was significantly altered due to oxygen-limitation in early log phase under these conditions. Broad functional categorization indicated that, in addition to genes involved in central metabolism, genes involved in adaptation to stress and genes likely involved with host interactions were affected by oxygen-availability. Notable among these, were genes encoding functions for motility, chemotaxis and biosynthesis of cobalamin, which were up-regulated and those for iron/heme utilization, methionine metabolism and urease, which were down-regulated. Conclusions/Significance This is the first transcriptome analysis of a non-pathogenic Yersinia spp. and one of few elucidating the global response to oxygen limitation for any of the yersiniae. Thus this study

  10. Crystal structure of the Yersinia type III secretion protein YscE

    SciTech Connect

    Phan, Jason; Austin, Brian P.; Waugh, David S.

    2010-12-06

    The plague-causing bacterium Yersinia pestis utilizes a contact-dependent (type III) secretion system (T3SS) to transport virulence factors from the bacterial cytosol directly into the interior of mammalian cells where they interfere with signal transduction pathways that mediate phagocytosis and the inflammatory response. The type III secretion apparatus is composed of 20-25 different Yersinia secretion (Ysc) proteins. We report here the structure of YscE, the smallest Ysc protein, which is a dimer in solution. The probable mode of oligomerization is discussed.

  11. Rapid identification of Yersinia pestis and Brucella melitensis by chip-based continuous flow PCR

    NASA Astrophysics Data System (ADS)

    Dietzsch, Michael; Hlawatsch, Nadine; Melzer, Falk; Tomaso, Herbert; Gärtner, Claudia; Neubauer, Heinrich

    2012-06-01

    To combat the threat of biological agents like Yersinia pestis and Brucella melitensis in bioterroristic scenarios requires fast, easy-to-use and safe identification systems. In this study we describe a system for rapid amplification of specific genetic markers for the identification of Yersinia pestis and Brucella melitensis. Using chip based PCR and continuous flow technology we were able to amplify the targets simultaneously with a 2-step reaction profile within 20 minutes. The subsequent analysis of amplified fragments by standard gel electrophoresis requires another 45 minutes. We were able to detect both pathogens within 75 minutes being much faster than most other nucleic acid amplification technologies.

  12. 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., ...

  13. Purification and characterization of Yersinia enterocolitica and Yersinia pestis LcrV–cholera toxin A2/B chimeras

    PubMed Central

    Davis, Chadwick T.; Arlian, Britni M.

    2010-01-01

    Yersinia pestis is a virulent human pathogen and potential biological weapon. Despite a long history of research on this organism, there is no licensed vaccine to protect against pneumonic forms of Y. pestis disease. In the present study, plasmids were constructed to express cholera toxin A2/B chimeric molecules containing the LcrV protective antigen from Y. enterocolitica and Y. pestis. These chimeras were expressed and purified to high yields from the supernatant of transformed E. coli. Western and GM1 ELISA assays were used to characterize the composition, receptor-binding and relative stability of the LcrV-CTA2/B chimera in comparison to cholera toxin. In addition, we investigated the ability of the Y. pestis LcrV-CTA2/B chimera to bind to and internalize into cultured epithelial cells and macrophages by confocal microscopy. These studies indicate that the uptake and trafficking of the LcrV antigen from the chimera is comparable to the trafficking of native toxin. Together these findings report that stable, receptor-binding, non-toxic LcrV-cholera toxin A2/B chimeras can be expressed at high levels in E. coli and purified from the supernatant. In addition, the internalization of antigen in vitro reported here supports the development of these molecules as novel mucosal vaccine candidates. PMID:20438844

  14. Lipid metabolism in tumour bearing mice treated withAeromonas L-asparaginase.

    PubMed

    Benny, P J; Kurup, G M; Sreejith, K

    1997-07-01

    The anticancerous drug isolated in our laboratory from estuarineAeromonas was characterised and is found to be an enzyme, L-asparaginase. The antileukaemic effect of this drug was studied in mice by inducing leukaemia with Ehrlich ascites cell lines. It was compared with commercially available drug, Leunase, isolated fromE. coli. The lipid profiles in mice during leukaemia and under treatment was studied. The decreased levels of cholesterol and increased levels of triglycerides and phospholipids in serum, liver and kidney were observed in tumour bearing mice. Significant changes in the above values were observed with enzyme therapy. It could bring some of the values to near normal level. L-asparaginase fromAeromonas was found to be more effective.

  15. The Social Life of Aeromonas through Biofilm and Quorum Sensing Systems

    PubMed Central

    Talagrand-Reboul, Emilie; Jumas-Bilak, Estelle; Lamy, Brigitte

    2017-01-01

    Bacteria of the genus Aeromonas display multicellular behaviors herein referred to as “social life”. Since the 1990s, interest has grown in cell-to-cell communication through quorum sensing signals and biofilm formation. As they are interconnected, these two self-organizing systems deserve to be considered together for a fresh perspective on the natural history and lifestyles of aeromonads. In this review, we focus on the multicellular behaviors of Aeromonas, i.e., its social life. First, we review and discuss the available knowledge at the molecular and cellular levels for biofilm and quorum sensing. We then discuss the complex, subtle, and nested interconnections between the two systems. Finally, we focus on the aeromonad multicellular coordinated behaviors involved in heterotrophy and virulence that represent technological opportunities and applied research challenges. PMID:28163702

  16. Potential of Psidium guajava supplemented fish diets in controlling Aeromonas hydrophila infection in tilapia (Oreochromis niloticus).

    PubMed

    Pachanawan, Adithepchaikarn; Phumkhachorn, Parichat; Rattanachaikunsopon, Pongsak

    2008-11-01

    Fourteen herbs were extracted in water, 95% ethanol, and ether, and tested in vitro for antimicrobial activities against Aeromonas hydrophila, a fish pathogen causing motile Aeromonas septicemia. Using swab paper disc assays and minimal inhibitory concentration (MIC) determinations, we noted that the ethanol extract of Psidium guajava leaf exhibited the strongest antimicrobial activity. The extract allowed growth-inhibited A. hydrophila cells to regrow in fresh BHI broth indicating a bacteriostatic mode of action. In a pathogenicity test, the median lethal dose (LD(50)) of A. hydrophila for tilapia (Oreochromis niloticus) by intraperitoneal injection was 3.44 x 10(6) CFU/ml. In vivo experiments showed that fish diets containing either dry leaf powder of P. guajava or dried ethanol extract of P. guajava leaf reduced mortality of A. hydrophila infected tilapia with no detected adverse effect on the fish. This study suggests that P. guajava leaf has the potential to control fish diseases caused by A. hydrophila.

  17. Diagnosis of Aeromonas hydrophila, Mycobacterium species, and Batrachochytrium dendrobatidis in an African Clawed Frog (Xenopus laevis)

    PubMed Central

    Hill, William A; Newman, Shelley J; Craig, Linden; Carter, Christopher; Czarra, Jane; Brown, J Paige

    2010-01-01

    Here we describe diagnosis of concurrent infection with Aeromonas hydrophila, Mycobacterium spp., and Batrachochytrium dendrobatidis in a wild female Xenopus laevis captured in Chile and transported to the United States. After approximately 130 d in the laboratory, the frog was presented for dysecdysis and obtundation. After euthanasia, tissues were submitted for histopathologic evaluation and PCR analysis for B. dendrobatidis and Ranavirus. Clinically significant gross lesions included cutaneous ulcerations on the lip, right forelimb, and ventral chest. Microscopic findings included regionally extensive splenic necrosis, diffuse pneumonia, and fibrinous coelomitis all containing intralesional bacteria. PCR analysis yielded positive results for B. dendrobatidis only. Bacterial culture of the ulcerated skin and liver yielded A. hydrophila. Infection with Contracaecum spp. was diagnosed as an incidental finding. To our knowledge, this case is the first report of simultaneous infection with Aeromonas hydrophila, Mycobacterium spp., and Batrachochytrium dendrobatidis in a laboratory-maintained X. laevis captured from the wild. PMID:20353698

  18. 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.

  19. Experimental challenge studies in Vietnamese catfish, Pangasianodon hypophthalmus (Sauvage), exposed to Edwardsiella ictaluri and Aeromonas hydrophila.

    PubMed

    Crumlish, M; Thanh, P C; Koesling, J; Tung, V T; Gravningen, K

    2010-09-01

    The two main diseases in the pangasius catfish industry are bacillary necrosis of Pangasianodon (BNP) and motile aeromonas septicaemia (MAS), where the aetiological agents have been identified as Edwardsiella ictaluri and Aeromonas hydrophila, respectively. In this study, apparently healthy Pangasianodon hypophthalmus were exposed to E. ictaluri, A. hydrophila or both bacterial species by intraperitoneal injection or immersion. There were 20 fish per treatment group, and the bacterial isolates used for the study were recovered from natural infections of BNP or MAS in farmed Vietnamese P. hypophthalmus. The results of the experimental infections mimicked the natural disease outbreaks reported from these pathogens in P. hypophthalmus. Furthermore, it was clearly demonstrated that E. ictaluri was only recovered from the fish exposed to the bacterium and not recovered from the animals receiving A. hydrophila.

  20. Aeromonas Hydrophila Endocarditis with Ruptured Mycotic Aneurysm of Right Renal Artery

    PubMed Central

    Pugliese, Maria Elena; Falcone, Marco; Oliva, Alessandra; Faccenna, Federico; D’Aluisio, Denise; Morelli, Sergio

    2016-01-01

    Aeromonas hydrophila has been infrequently reported as a cause of infection in humans. It has been associated with a variety of clinical syndromes but Aeromonas-related endocarditis is extremely rare. We present the case of a 76-year-old diabetic patient who was admitted to our hospital due to severe lumbar pain resistant to nonsteroidal anti-inflammatory drugs accompanied by fever (up to 38.5°C). The vital signs were normal and the physical examination was unremarkable except for tenderness over right flank. Laboratory investigation showed a mild leukocytosis (white blood cell count of 11,360×106/L) with elevation of inflammatory markers. Cardiac ultrasound showed a large vegetation on the mitral valve. Abdominal computed tomogrpahy revealed a ruptured aneurysm of the right renal artery. Multiple sets of blood culture grew A. hydrophila.

  1. Pathogenicity of Aeromonas hydrophila, Klebsiella pneumoniae, and Proteus mirabilis to brown tree frogs (Litoria ewingii).

    PubMed

    Schadich, Ermin; Cole, Anthony L J

    2010-04-01

    Bacterial dermatosepticemia, a systemic infectious bacterial disease of frogs, can be caused by several opportunistic gram-negative bacterial species including Aeromonas hydrophila, Chryseobacterium indologenes, Chryseobacterium meningosepticum, Citrobacter freundii, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, and Serratia liquifaciens. Here we determined the pathogenicity of 3 bacterial species (Aeromonas hydrophila, Klebsiella pneumoniae, and Proteus mirabilis) associated with an outbreak of fatal dermatosepticemia in New Zealand Litoria ewingii frogs. A bath challenge method was used to expose test frogs to individual bacterial species (2 x 10(7) cfu/mL in pond water); control frogs were exposed to uninfected pond water. None of the control frogs or those exposed to A. hydrophila or P. mirabilis showed any morbidity or mortality. Morbidity and mortality was 40% among frogs exposed to K. pneumonia, and the organism was reisolated from the hearts, spleens, and livers of affected animals.

  2. A comparison of different culture media for the membrane filter quantification of Aeromonas in water.

    PubMed

    Villari, P; Pucino, A; Santagata, N; Torre, I

    1999-10-01

    A comparative assessment of culture media for the membrane filter enumeration of Aeromonas spp. in water was performed, testing the effects of different incubation conditions (aerobic and anaerobic), temperatures (30 and 37 degrees C) and times (24 and 48 h). Different water samples seeded with test suspensions of Aeromonas spp., fecal material or raw sewage were examined. Results indicate clearly that plates should be incubated aerobically at 30 degrees C for 24 h. If the bacterial contamination is likely to be low, the use of most sensitive culture media, such as SAA, mA, ADA or PADE Agar, is recommended. By contrast, samples with an expected high level of background microbial flora should be analysed through more selective media, such as MIX Agar. However, the low selectivity of all media tested and the high likelihood of false negatives based upon the macroscopic examination of colonies means that further research directed to the development of more efficient media is needed.

  3. Influence of food system conditions on N-acyl-L-homoserine lactones production by Aeromonas spp.

    PubMed

    Medina-Martínez, M S; Uyttendaele, M; Demolder, V; Debevere, J

    2006-12-01

    Eleven of 13 Aeromonas strains were shown to produce AHLs. Results of TLC showed that N-butanoyl-L-homoserine lactone (C4-HSL) was the main AHL produced in LB medium at 30 degrees C. The influence of different carbon sources, temperature, pH values and salt concentrations on AHL production was determined in eight A. hydrophila and one A. caviae strain. Additionally a quantitative study of C4-HSL production by A. hydrophila strain 519 under different conditions was performed. Positive results were found in the AHL induction assay for some Aeromonas strains in cultures in LB agar incubated at 12 degrees C after 72-96 h. The induction of the sensor strains by Aeromonas spp. occurred in LB medium supplemented with all carbon sources in a concentration of 0.5%. The production of C4-HSL by A. hydrophila 519 was found until 3.5% (w/v) of NaCl. For pHs close to the neutrality the C4-HSL production by A. hydrophila was evident after 24-48 h of incubation. A. hydrophila 519 produced C4-HSL under anaerobic conditions. Also, the AHL production by Aeromonas strains was studied in simulate agar of shrimp, fish and some vegetables. The production of AHLs was evident by almost all the test strains in shrimp simulated agar. In fish agar only for one of three fish species tested, positive results were found. Induction assay in vegetables simulated agar showed principally negative results, probably because of the presence of inhibitory compounds in these vegetables.

  4. Preparation of Metabolically Active Staphylococcus aureus Protoplasts by Use of the Aeromonas hydrophila Lytic Enzyme

    PubMed Central

    Coles, N. W.; Gross, R.

    1973-01-01

    Stable, metabolically active protoplasts of Staphylococcus aureus have been prepared by the use of a staphylolytic enzyme produced by Aeromonas hydrophila. Respiratory and glycolytic rates and synthesis of nucleic acids, protein, and lipid in these protoplasts, stabilized variously in 1.1 M sucrose, 0.37 M sodium succinate, or 0.37 M sodium sulfate, have been shown to be comparable with the same parameters in intact cells under the same conditions. Images PMID:4728270

  5. Bioinformatic Genome Comparisons for Taxonomic and Phylogenetic Assignments Using Aeromonas as a Test Case

    PubMed Central

    Colston, Sophie M.; Fullmer, Matthew S.; Beka, Lidia; Lamy, Brigitte

    2014-01-01

    ABSTRACT Prokaryotic taxonomy is the underpinning of microbiology, as it provides a framework for the proper identification and naming of organisms. The “gold standard” of bacterial species delineation is the overall genome similarity determined by DNA-DNA hybridization (DDH), a technically rigorous yet sometimes variable method that may produce inconsistent results. Improvements in next-generation sequencing have resulted in an upsurge of bacterial genome sequences and bioinformatic tools that compare genomic data, such as average nucleotide identity (ANI), correlation of tetranucleotide frequencies, and the genome-to-genome distance calculator, or in silico DDH (isDDH). Here, we evaluate ANI and isDDH in combination with phylogenetic studies using Aeromonas, a taxonomically challenging genus with many described species and several strains that were reassigned to different species as a test case. We generated improved, high-quality draft genome sequences for 33 Aeromonas strains and combined them with 23 publicly available genomes. ANI and isDDH distances were determined and compared to phylogenies from multilocus sequence analysis of housekeeping genes, ribosomal proteins, and expanded core genes. The expanded core phylogenetic analysis suggested relationships between distant Aeromonas clades that were inconsistent with studies using fewer genes. ANI values of ≥96% and isDDH values of ≥70% consistently grouped genomes originating from strains of the same species together. Our study confirmed known misidentifications, validated the recent revisions in the nomenclature, and revealed that a number of genomes deposited in GenBank are misnamed. In addition, two strains were identified that may represent novel Aeromonas species. PMID:25406383

  6. Complex Evolutionary History of the Aeromonas veronii Group Revealed by Host Interaction and DNA Sequence Data

    PubMed Central

    Faucher, Joshua; Horneman, Amy J.; Gogarten, J. Peter; Graf, Joerg

    2011-01-01

    Aeromonas veronii biovar sobria, Aeromonas veronii biovar veronii, and Aeromonas allosaccharophila are a closely related group of organisms, the Aeromonas veronii Group, that inhabit a wide range of host animals as a symbiont or pathogen. In this study, the ability of various strains to colonize the medicinal leech as a model for beneficial symbiosis and to kill wax worm larvae as a model for virulence was determined. Isolates cultured from the leech out-competed other strains in the leech model, while most strains were virulent in the wax worms. Three housekeeping genes, recA, dnaJ and gyrB, the gene encoding chitinase, chiA, and four loci associated with the type three secretion system, ascV, ascFG, aexT, and aexU were sequenced. The phylogenetic reconstruction failed to produce one consensus tree that was compatible with most of the individual genes. The Approximately Unbiased test and the Genetic Algorithm for Recombination Detection both provided further support for differing evolutionary histories among this group of genes. Two contrasting tests detected recombination within aexU, ascFG, ascV, dnaJ, and gyrB but not in aexT or chiA. Quartet decomposition analysis indicated a complex recent evolutionary history for these strains with a high frequency of horizontal gene transfer between several but not among all strains. In this study we demonstrate that at least for some strains, horizontal gene transfer occurs at a sufficient frequency to blur the signal from vertically inherited genes, despite strains being adapted to distinct niches. Simply increasing the number of genes included in the analysis is unlikely to overcome this challenge in organisms that occupy multiple niches and can exchange DNA between strains specialized to different niches. Instead, the detection of genes critical in the adaptation to specific niches may help to reveal the physiological specialization of these strains. PMID:21359176

  7. Complex evolutionary history of the Aeromonas veronii group revealed by host interaction and DNA sequence data.

    PubMed

    Silver, Adam C; Williams, David; Faucher, Joshua; Horneman, Amy J; Gogarten, J Peter; Graf, Joerg

    2011-02-16

    Aeromonas veronii biovar sobria, Aeromonas veronii biovar veronii, and Aeromonas allosaccharophila are a closely related group of organisms, the Aeromonas veronii Group, that inhabit a wide range of host animals as a symbiont or pathogen. In this study, the ability of various strains to colonize the medicinal leech as a model for beneficial symbiosis and to kill wax worm larvae as a model for virulence was determined. Isolates cultured from the leech out-competed other strains in the leech model, while most strains were virulent in the wax worms. Three housekeeping genes, recA, dnaJ and gyrB, the gene encoding chitinase, chiA, and four loci associated with the type three secretion system, ascV, ascFG, aexT, and aexU were sequenced. The phylogenetic reconstruction failed to produce one consensus tree that was compatible with most of the individual genes. The Approximately Unbiased test and the Genetic Algorithm for Recombination Detection both provided further support for differing evolutionary histories among this group of genes. Two contrasting tests detected recombination within aexU, ascFG, ascV, dnaJ, and gyrB but not in aexT or chiA. Quartet decomposition analysis indicated a complex recent evolutionary history for these strains with a high frequency of horizontal gene transfer between several but not among all strains. In this study we demonstrate that at least for some strains, horizontal gene transfer occurs at a sufficient frequency to blur the signal from vertically inherited genes, despite strains being adapted to distinct niches. Simply increasing the number of genes included in the analysis is unlikely to overcome this challenge in organisms that occupy multiple niches and can exchange DNA between strains specialized to different niches. Instead, the detection of genes critical in the adaptation to specific niches may help to reveal the physiological specialization of these strains.

  8. Draft Genome Sequence of Aeromonas sobria Strain 08005, Isolated from Sick Rana catesbeiana

    PubMed Central

    Yang, Qiu-Hua; Zhou, Chen; Lin, Qi; Lu, Zhen; He, Li-Bin

    2017-01-01

    ABSTRACT Aeromonas sobria is a Gram-negative, rod-shaped, and ubiquitous bacterium. We present here the draft genome sequence of A. sobria strain 08005, isolated from an infected bullfrog. It is composed of 66 contigs totaling 4,678,951 bp, contains 4,252 coding DNA sequences (CDSs), four rRNAs, and 88 tRNA sequences, and shows the presence of various putative virulence-related genes. PMID:28082483

  9. Virulence properties and enterotoxin production of Aeromonas strains isolated from fish.

    PubMed Central

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

    1988-01-01

    The biological activities in vivo and in vitro of 59 motile Aeromonas spp. isolated from fish and water tanks were simultaneously analyzed in poikilothermic and homoiothermic systems. A total of 64.3% of the isolates tested were pathogenic for fish, and 62% of Aeromonas hydrophila and A. sobria isolates either virulent or nonvirulent for fish were enterotoxigenic. Although the majority of the strains were proteolytic and amylolytic and produced DNase, other activities, such as elastase and staphylolysis, were only present in A. hydrophila. Most of the strains (96%) produced hemolysins, and 68% had agglutinating capacity, but neither isolates pathogenic for fish nor enterotoxigenic isolates showed specificity for trout or human erythrocytes, respectively. The production of siderophores, agglutination in acriflavine, and precipitation after boiling were found not to be useful tests for screening virulent strains. Although statistical analysis revealed a significant relationship between virulence for fish and positive results for arabinose and sucrose fermentations, elastase, and hemolysis of human erythrocytes, only lysine decarboxylase showed a significant positive relationship with enterotoxigenicity. Using extracellular products from representative Aeromonas strains with different virulence markers and belonging to distinct O serogroups, we demonstrated a lack of correlation between cytotoxicity for fish and homoiothermic cell lines and pathogenicity. The extracellular products from selected pathogenic A. hydrophila strains were lethal for rainbow trout and displayed proteolytic, hemolytic, and cytotoxic activities which were simultaneously lost after heat treatment. The findings reported here indicate that it is not possible to establish a common and single mechanism involved in the invasion of Aeromonas spp. in poikilothermic and homoiothermic hosts. Images PMID:2972627

  10. Evaluation of four molecular typing methodologies as tools for determining taxonomy relations and for identifying species among Yersinia isolates.

    PubMed

    Souza, Roberto A; Pitondo-Silva, André; Falcão, Deise P; Falcão, Juliana P

    2010-08-01

    In the last few decades, molecular typing has become an important tool in taxonomic, phylogenetic and identification studies of numerous groups of bacteria, including the yersiniae. In this study, Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR), Pulsed-Field Gel Electrophoresis (PFGE), 16S rRNA gene sequencing and Multilocus Sequence Analysis (MLSA) were performed to determine the ability of these techniques to be used in taxonomy and identification of Yersinia strains. A total of 60 Yersinia strains were genotyped by ERIC-PCR and PFGE. Moreover, an in silico analysis was carried out for 16S rRNA gene sequencing and MLSA, using 68 and 49 Yersinia strains, respectively. A phylogenetic tree constructed from the ERIC-PCR, 16S rRNA gene sequencing and MLSA data grouped most of the Yersinia species into distinct species-specific clusters. In the PFGE assay these clusters were not observed. On this basis, ERIC-PCR, 16S rRNA gene sequencing and MLSA seem to be valuable techniques for use in taxonomic and identification studies of the genus Yersinia, whereas PFGE does not. Furthermore, ERIC-PCR has the advantage of being a cheaper, easier and faster assay than 16S rRNA gene sequencing or MLSA, and for these reasons can be considerate an alternative tool in taxonomic studies of yersiniae.

  11. 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.

  12. Aeromonas hydrophila-associated septicemia in captive crocodiles (Crocodylus johnstoni and Crocodylus porosus).

    PubMed

    Roh, Yoon-Seok; Park, Heejin; Cho, Hyun-Ung; Cho, Ara; Islam, Mohammad Rafiqul; Cho, Ho-Seong; Lim, Chae Woong; Kim, Bumseok

    2011-12-01

    Five 25-yr-old crocodiles (Crocodylus johnstoni and Crocodylus porosus) were diagnosed with Aeromonas hydrophila-associated septicemia accelerated by improper thermoregulation. At necropsy, pulmonary congestion and pleural effusion were the main lesions in the thorax. Necrotizing enteritis, intestinal hemorrhage, fibrinous serositis, hepatitis, and pancreatitis were observed in the abdominal cavities of all five crocodiles. Aeromonas hydrophila was identified in the pleural effusions and abdominal ascites of all necropsied crocodiles by using an API system 20NE. Aeromonas hydrophila infection and evaluation of virulence were confirmed by polymerase chain reaction targeting the 16S rRNA and extracellular hemolysin gene. The crocodiles in the present case were housed in an indoor facility at a private zoo that failed to optimize land and water portions of the enclosure, exposing the animals to impeded thermoregulation, and it is suggested that the pathogenesis was accelerated by the improper thermoregulation-induced stress. This is the first description of A. hydrophila pathogenicity associated with impeded thermoregulation in reptiles.

  13. The Genus Aeromonas: Biochemical Characteristics, Atypical Reactions, and Phenotypic Identification Schemes

    PubMed Central

    Abbott, Sharon L.; Cheung, Wendy K. W.; Janda, J. Michael

    2003-01-01

    A total of 193 strains representing 14 different Aeromonas genomospecies were evaluated for 63 phenotypic properties to create useful tables for the reference identification of mesophilic aeromonads. Only 9 of 62 biochemical tests (14%) yielded uniform results, and the fermentation of certain carbohydrates was found to be linked to specific species. A number of unusual or aberrant properties for the genus Aeromonas were also detected in the collection of 428 strains (193 in the phenotypic study, 235 in a retrospective review). These tests included susceptibility to the vibriostatic agent, fermentation of m-inositol and d-xylose, hydrolysis of urea, and the lack of cytochrome oxidase activity. Fermentation of melibiose was linked to raffinose fermentation in all Aeromonas species except A. jandaei. Keys are provided for clinical laboratories choosing to identify aeromonads to species level based upon initial Møeller decarboxylase and dihydrolase reactions. In addition, several new tests were identified that help to separate members of the A. caviae complex (A. caviae, A. media, and A. eucreonophila). PMID:12791848

  14. Bacteriocin-like substance (BLS) production in Aeromonas hydrophila water isolates.

    PubMed

    Messi, Patrizia; Guerrieri, Elisa; Bondi, Moreno

    2003-03-14

    30 Aeromonas hydrophila water isolates were tested for bacteriocin-like substance (BLS) production using a target panel of closely related microorganisms and other Gram-positive and Gram-negative bacteria, including food-borne pathogens. A. hydrophila showed antibacterial activity against one or more indicator microorganisms, but the activity emerged only with non-phylogenetically related genera or species. In particular all A. hydrophila showed antibacterial activity against one or more of the tested Staphylococcus strains, five against Listeria spp. (Listeria seeligeri, Listeria welshimeri and Listeria ivanovii), and eight presented a weak antagonistic activity towards Streptococcus agalactiae and Lactobacillus spp. Inhibitory activity was not observed against the other Gram-positive (Listeria monocytogenes, Listeria innocua and Enterococcus spp.) and Gram-negative tested strains, including Aeromonas sobria, Aeromonas caviae and the same A. hydrophila, when used as indicator. Anti-staphylococcal activity was observed with a gradual increase of the inhibition zone during incubation and seemed to be influenced by A. hydrophila hemolytic expression. Extrachromosomal analysis showed the presence, in 70% of the strains, of one to five plasmids with molecular masses ranging from 2.1 to 41.5 MDa, but it was not possible to relate this result with BLS production.

  15. Inactivation of Aeromonas hydrophila by Fe(II)-related-radical generation in oxidizing groundwaters.

    PubMed Central

    Kersters, I; Verstraete, W

    1996-01-01

    The survival of Aeromonas hydrophila AWWX1 in filter-sterilized phreatic groundwaters was studied by using viable counts. Aeromonas counts rapidly decreased 2 to 3 log units in oxidizing raw groundwaters from Snellegem and Beernem, Belgium (Snellegem-raw and Beernem-raw, respectively), containing high concentrations of Fe2+ (460 to 1,070 microM). The rapid decline in viable counts of Aeromonas cells in the oxidizing raw groundwater of Snellegem was prevented by the addition of an Fe2+ chelator (2,2'-dipyridyl) or compounds (i.e., ascorbic acid and catalase) that act on toxic oxygen species. The results suggest that free radicals, generated spontaneously in oxidizing Fe2+-containing groundwaters, caused the inactivation of A. hydrophila AWWX1. Evidence that free radicals are generated under the given conditions was provided by the observation that propylphosphonic acid, a compound which is very susceptible to radicals, was degraded upon addition to these waters. A. hydrophila PWBS, Pseudomonas fluorescens P17, Spirillum strain NOX, and heterotrophs showed decreases in culturability in filter-sterilized Snellegem-raw water similar to that shown by A. hydrophila AWWX1. These findings indicate that free radicals generated in Fe2+-containing groundwaters upon aeration are capable of inactivating various bacterial species. PMID:8795217

  16. A Disease Model of Muscle Necrosis Caused by Aeromonas dhakensis Infection in Caenorhabditis elegans

    PubMed Central

    Chen, Po-Lin; Chen, Yi-Wei; Ou, Chun-Chun; Lee, Tzer-Min; Wu, Chi-Jung; Ko, Wen-Chien; Chen, Chang-Shi

    2017-01-01

    A variety of bacterial infections cause muscle necrosis in humans. Caenorhabditis elegans has epidermis and bands of muscle that resemble soft-tissue structures in mammals and humans. Here, we developed a muscle necrosis model caused by Aeromonas dhakensis infection in C. elegans. Our data showed that A. dhakensis infected and killed C. elegans rapidly. Characteristic muscle damage in C. elegans induced by A. dhakensis was demonstrated in vivo. Relative expression levels of host necrosis-associated genes, asp-3, asp-4, and crt-1 increased significantly after A. dhakensis infection. The RNAi sensitive NL2099 rrf-3 (pk1426) worms with knockdown of necrosis genes of crt-1 and asp-4 by RNAi showed prolonged survival after A. dhakensis infection. Specifically knockdown of crt-1 and asp-4 by RNAi in WM118 worms, which restricted RNAi only to the muscle cells, conferred significant resistance to A. dhakensis infection. In contrast, the severity of muscle damage and toxicity produced by the A. dhakensis hemolysin-deletion mutant is attenuated. In another example, shiga-like toxin-producing enterohemorrhagic E. coli (EHEC) known to elicit toxicity to C. elegans with concomitant enteropathogenicty, did not cause muscle necrosis as A. dhakensis did. Taken together, these results show that Aeromonas infection induces muscle necrosis and rapid death of infected C. elegans, which are similar to muscle necrosis in humans, and then validate the value of the C. elegans model with A. dhakensis infection in studying Aeromonas pathogenicity. PMID:28101079

  17. Quorum Sensing Activity of Aeromonas Caviae Strain YL12, A Bacterium Isolated from Compost

    PubMed Central

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

    2014-01-01

    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. PMID:24759107

  18. [Cloning and expression of a hemolysin gene of Aeromonas hydrophila and the immunogenicity of the toxoid].

    PubMed

    Zhang, Cuijuan; Yu, Zhouliang; Tian, Liying; Zhao, Baohua

    2009-02-01

    According to the GenBank sequences (GenBank Accession No. AF539467), one pair of primers was designed to amplify hly gene of Aeromonas hydrophila by PCR. After sequencing, homology analysis indicated that a DNA fragment of 1485 bp was amplified from isolated DNA from Aeromonas hydrophila, and it shared more than 99% homology in nucleotide sequence compared with other reference strains in GenBank. The gene was cloned in pET-28a vector to construct a recombinant plasmid pET-28a-hly, which was transformed into Escherichia coli BL21 (DE3), and the recombinant strain BL21(DE3)(pET-28a-hly) was obtained. The hemolysin was highly expressed when the recombinant strain BL21 (DE3) (pET-28a-hly) was induced by IPTG. The expressed protein was 56 kD as estimated by 15% SDS-polyacrylamide gel electrophoresis (SDS-PAGE). The immunogenicity of the expressed Hly protein was confirmed by Western blotting. Mice were immunized with inactivated whole bacteria vaccine and the genetic engineering vaccines showing promise that all these vaccines have a high protective ability. The results showed that the recombinant strain BL21 (DE3)(pET-28a-hly) could be candidate of hemolysin toxoid vaccine to provide protective immunity against diseases caused by Aeromonas hydrophila.

  19. Population dynamics, antibiotics resistance and biofilm formation of Aeromonas and Vibrio species isolated from aquatic sources in Northern Malaysia.

    PubMed

    Odeyemi, Olumide A; Ahmad, Asmat

    2017-02-01

    This study aimed to compare population dynamics, antibiotic resistance and biofilm formation of Aeromonas and Vibrio species from seawater and sediment collected from Northern Malaysia. Isolates with different colony morphology were characterized using both biochemical and molecular methods before testing for antibiotic resistance and biofilm formation. Results obtained from this study showed that in Kedah, the population of Aeromonas isolated from sediment was highest in Pantai Merdeka (8.22 log CFU/ml), Pulau Bunting recorded the highest population of Aeromonas from sediment (8.43 log CFU/g). It was observed that Vibrio species isolated from seawater and sediment were highest in Kuala Sanglang (9.21 log CFU/ml). In Kuala Perlis, the population of Aeromonas isolated from seawater was highest in Jeti (7.94 log CFU/ml). Highest population of Aeromonas from sediment was recorded in Kampong Tanah Baru (7.99 log CFU/g). It was observed that Vibrio species isolated from seawater was highest in Padang Benta (8.42 log CFU/g) while Jeti Kuala Perlis had highest population of Vibrio isolated from sediment. It was observed that location does not influence population of Aeromonas. The results of the independent t - test revealed that there was no significant relationship between location and population of Vibrio (df = 10, t = 1.144, p > 0.05). The occurrence of biofilm formation and prevalence of antibiotic resistant Aeromonas and Vibrio species in seawater and sediment pose danger to human and aquatic animals' health.

  20. Potentials and limits for the use of ozone as a fish disease control agent

    USGS Publications Warehouse

    Wedemeyer, Gary A.; Nelson, Nancy C.; Yasutake, Wm. T.

    1979-01-01

    Ozone and chlorine inactivation curves were determined in three types of freshwater at 20 C for the destruction of the fish pathogens Aeromonas salmonicida the etiologic agent of furunculosis, and Yersinia ruckeri the enteric redmouth bacterium (ERM). Ozone and chlorine inactivation curves were also obtained in the same water types at 10 C for the fish pathogenic viruses infectious hematopoietic necrosis (IHNV), and infectious pancreatic necrosis (IPNV). Acute toxicity tests using the rainbow trout as a representative salmonid revealed that ozone was highly toxic at the dose levels used. Partial chronic (3. mo.) testing revealed that ozone exposure at 2 μg/L causes only minimal physiological changes, none of which would be expected to compromise biological function.

  1. Yersinia pestis YopM: thrombin binding and overexpression.

    PubMed Central

    Reisner, B S; Straley, S C

    1992-01-01

    In previous studies, Yersinia pestis YopM has been shown through mutational analysis to be necessary for virulence in mice and found to have homology with the thrombin-binding domain of the platelet receptor GPIb alpha. In this study, YopM was purified and shown by dot blot and chemical cross-linking tests to bind to human alpha-thrombin. No cross-linked product could be detected when human prothrombin was incubated with YopM. As a functional test of thrombin binding, it was shown that native but not boiled YopM inhibits thrombin-induced aggregation of human platelets. Control tests showed that YopM did not inactivate the platelets themselves, nor was its effect a nonspecific consequence of its very acidic isoelectric point. Microsequencing of YopM revealed an intact N terminus, indicating that functional YopM is not processed at the N terminus or secreted by a mechanism involving a cleavable signal sequence. Further characterization was made of an interesting effect on yopM expression that had been noticed in a previous study. A 1.5-kb HaeIII subclone overexpressed YopM in both Y. pestis and Escherichia coli compared with a larger clone containing the 5.3-kb HindIII-F fragment. To search for a possible regulator of YopM expression, the HindIII-F fragment was sequenced, revealing several open reading frames and three large repeated sequences. Deletional analysis showed that these were not involved in regulation of yopM. The data implicated a DNA structure 5' to yopM in moderating yopM expression. Images PMID:1452357

  2. LPS modification promotes maintenance of Yersinia pestis in fleas

    PubMed Central

    Aoyagi, Kari L.; Brooks, Benjamin D.; Bearden, Scott W.; Montenieri, John A.; Gage, Kenneth L.

    2015-01-01

    Yersinia pestis, the causative agent of plague, can be transmitted by fleas by two different mechanisms: by early-phase transmission (EPT), which occurs shortly after flea infection, or by blocked fleas following long-term infection. Efficient flea-borne transmission is predicated upon the ability of Y. pestis to be maintained within the flea. Signature-tagged mutagenesis (STM) was used to identify genes required for Y. pestis maintenance in a genuine plague vector, Xenopsylla cheopis. The STM screen identified seven mutants that displayed markedly reduced fitness in fleas after 4 days, the time during which EPT occurs. Two of the mutants contained insertions in genes encoding glucose 1-phosphate uridylyltransferase (galU) and UDP-4-amino-4-deoxy-l-arabinose-oxoglutarate aminotransferase (arnB), which are involved in the modification of lipid A with 4-amino-4-deoxy-l-arabinose (Ara4N) and resistance to cationic antimicrobial peptides (CAMPs). These Y. pestis mutants were more susceptible to the CAMPs cecropin A and polymyxin B, and produced lipid A lacking Ara4N modifications. Surprisingly, an in-frame deletion of arnB retained modest levels of CAMP resistance and Ara4N modification, indicating the presence of compensatory factors. It was determined that WecE, an aminotransferase involved in biosynthesis of enterobacterial common antigen, plays a novel role in Y. pestis Ara4N modification by partially offsetting the loss of arnB. These results indicated that mechanisms of Ara4N modification of lipid A are more complex than previously thought, and these modifications, as well as several factors yet to be elucidated, play an important role in early survival and transmission of Y. pestis in the flea vector. PMID:25533446

  3. Quorum sensing in Yersinia enterocolitica controls swimming and swarming motility.

    PubMed

    Atkinson, Steve; Chang, Chien-Yi; Sockett, R Elizabeth; Cámara, Miguel; Williams, Paul

    2006-02-01

    The Yersinia enterocolitica LuxI homologue YenI directs the synthesis of N-3-(oxohexanoyl)homoserine lactone (3-oxo-C6-HSL) and N-hexanoylhomoserine lactone (C6-HSL). In a Y. enterocolitica yenI mutant, swimming motility is temporally delayed while swarming motility is abolished. Since both swimming and swarming are flagellum dependent, we purified the flagellin protein from the parent and yenI mutant. Electrophoresis revealed that in contrast to the parent strain, the yenI mutant grown for 17 h at 26 degrees C lacked the 45-kDa flagellin protein FleB. Reverse transcription-PCR indicated that while mutation of yenI had no effect on yenR, flhDC (the motility master regulator) or fliA (the flagellar sigma factor) expression, fleB (the flagellin structural gene) was down-regulated. Since 3-oxo-C6-HSL and C6-HSL did not restore swimming or swarming in the yenI mutant, we reexamined the N-acylhomoserine lactone (AHL) profile of Y. enterocolitica. Using AHL biosensors and mass spectrometry, we identified three additional AHLs synthesized via YenI: N-(3-oxodecanoyl)homoserine lactone, N-(3-oxododecanoyl)homoserine lactone (3-oxo-C12-HSL), and N-(3-oxotetradecanoyl)homoserine lactone. However, none of the long-chain AHLs either alone or in combination with the short-chain AHLs restored swarming or swimming in the yenI mutant. By investigating the transport of radiolabeled 3-oxo-C12-HSL and by introducing an AHL biosensor into the yenI mutant we demonstrate that the inability of exogenous AHLs to restore motility to the yenI mutant is not related to a lack of AHL uptake. However, both AHL synthesis and motility were restored by complementation of the yenI mutant with a plasmid-borne copy of yenI.

  4. Yersinia enterocolitica: a review of its role in food hygiene*

    PubMed Central

    Morris, G. K.; Feeley, J. C.

    1976-01-01

    Since Yersinia enterocolitica, now classified as a member of the Enterobacteriaceae, was recognized as a distinct species in 1964 it has been isolated with increasing frequency from man and animals (including dogs and pigs) and from some human foods. Y. enterocolitica infections are now seen as a cause for some concern in both human and veterinary medicine. The organism is commonly found in specimens from swine slaughterhouses and has been isolated from samples of market meat, vacuum-packed beef, mussels, oysters, and ice-cream. It has also been found in nonchlorinated well water used for drinking purposes. Infections in man therefore probably have an alimentary origin. Only 23 human infections were recorded in 1966 but the number increased to over 4000 in 1974. However, reported incidence is affected by growing awareness about the role of the organism in human and animal disease and by intensive laboratory analyses. While knowledge about the geographical distribution of Y. enterocolitica is still fragmentary it is clear that infections are very frequent in some parts of the world and probably common but unrecognized in many countries. The most common symptoms of Y. enterocolitica infections in man are fever, abdominal pain, and diarrhoea. In the USA most isolations in human infections were made from blood and mesenteric lymph node samples. The pathogenic mechanism is not known. In one experiment involving a human volunteer subject a dose of 3.5 × 109 organisms was required to produce an infection. Only recently has some success been obtained in establishing experimental infections in mice, guinea-pigs, rats, and rabbits. Laboratory cultivation techniques for Y. enterocolitica are described together with a table of minimal tests for characterizing the organism and two biotyping schema. Little is known about methods for controlling this disease, but environmental hygiene and sanitation with regard to food and water should apply. PMID:1087589

  5. Superantigen YPMa Exacerbates the Virulence of Yersinia pseudotuberculosis in Mice

    PubMed Central

    Carnoy, Christophe; Mullet, Chantal; Müller-Alouf, Heide; Leteurtre, Emmanuelle; Simonet, Michel

    2000-01-01

    Yersinia pseudotuberculosis, a gram-negative bacterium responsible for enteric and systemic infection in humans, produces a superantigenic toxin designated YPMa (Y. pseudotuberculosis-derived mitogen). To assess the role of YPMa in the pathogenesis of Y. pseudotuberculosis, we constructed a superantigen-deficient mutant and compared its virulence in a mouse model of infection to the virulence of the wild-type strain. Determination of the survival rate after intravenous (i.v.) bacterial inoculation of OF1 mice clearly showed that inactivation of ypmA, encoding YPMa, reduced the virulence of Y. pseudotuberculosis. Mice infected i.v. with 104 and 105 wild-type bacteria died within 9 days, whereas mice infected with the ypmA mutant survived 12 and 3 days longer, respectively. This decreased virulence of the ypmA mutant strain was not due to an impaired colonization of the spleen, liver, or lungs. In contrast to i.v. challenge, bacterial inoculation by the intragastric (i.g.) route did not reveal any difference in virulence between wild-type Y. pseudotuberculosis and the ypmA mutant since the 50% lethal doses were identical for both strains. Moreover, inactivation of ypmA gene did not affect the bacterial growth of Y. pseudotuberculosis in Peyer's patches, mesenteric lymph nodes (MLNs), and spleen after oral infection. Histological studies of spleen, liver, lungs, heart, Peyer's patches, and MLNs after i.v. or i.g. challenge with the wild type or the ypmA mutant did not reveal any feature that can be specifically related to YPMa. Our data show that the superantigenic toxin YPMa contributes to the virulence of Y. pseudotuberculosis in systemic infection in mice. PMID:10768943

  6. Recent findings about the Yersinia enterocolitica phage shock protein response.

    PubMed

    Yamaguchi, Saori; Darwin, Andrew J

    2012-02-01

    The phage shock protein (Psp) system is a conserved extracytoplasmic stress response in bacteria that is essential for virulence of the human pathogen Yersinia enterocolitica. This article summarizes some recent findings about Y. enterocolitica Psp system function. Increased psp gene expression requires the transcription factor PspF, but under non-inducing conditions PspF is inhibited by an interaction with another protein, PspA, in the cytoplasm. A Psp-inducing stimulus causes PspA to relocate to the cytoplasmic membrane, freeing PspF to induce psp gene expression. This PspA relocation requires the integral cytoplasmic membrane proteins, PspB and PspC, which might sense an inducing trigger and sequester PspA by direct interaction. The subsequent induction of psp gene expression increases the PspA concentration, which also allows it to contact the membrane directly, perhaps for its physiological function. Mutational analysis of the PspB and PspC proteins has revealed that they both positively and negatively regulate psp gene expression and has also identified PspC domains associated with each function. We also compare the contrasting physiological roles of the Psp system in the virulence of Y. enterocolitica and Salmonella enterica sv. Typhimurium (S. Typhimurium). In S. Typhimurium, PspA maintains the proton motive force, which provides the energy needed to drive ion importers required for survival within macrophages. In contrast, in the extracellular pathogen Y. enterocolitica, PspB and PspC, but not PspA, are the Psp components needed for virulence. PspBC protect Y. enterocolitica from damage caused by the secretin component of its type 3 secretion system, an essential virulence factor.

  7. Recent emergence of new variants of Yersinia pestis in Madagascar.

    PubMed

    Guiyoule, A; Rasoamanana, B; Buchrieser, C; Michel, P; Chanteau, S; Carniel, E

    1997-11-01

    Yersinia pestis, the causative agent of plague, has been responsible for at least three pandemics. During the last pandemic, which started in Hong Kong in 1894, the microorganism colonized new, previously unscathed geographical areas where it has become well established. The aim of this longitudinal study was to investigate the genetic stability of Y. pestis strains introduced into a new environment just under a century ago and to follow the epidemiology of any new genetic variant detected. In the present study, 187 strains of Y. pestis isolated between 1939 and 1996 from different regions of Madagascar and responsible mainly for human cases of bubonic and pneumonic plague were studied. Our principal genotyping method was rRNA gene profiling (ribotyping), which has previously been shown to be an effective scheme for typing Y. pestis strains of different geographical origins. We report that all studied Y. pestis strains isolated in Madagascar before 1982 were of classical ribotype B, the ribotype attributed to the Y. pestis clone that spread around the world during the third pandemic. In 1982, 1983, and 1994, strains with new ribotypes, designated R, Q, and T, respectively, were isolated on the high-plateau region of the island. Analysis of other genotypic traits such as the NotI genomic restriction profiles and the EcoRV plasmid restriction profiles revealed that the new variants could also be distinguished by specific genomic and/or plasmid profiles. A follow-up of these new variants indicated that strains of ribotypes Q and R have become well established in their ecosystem and have a tendency to spread to new geographical areas and supplant the original classical strain.

  8. A Precise Temperature-Responsive Bistable Switch Controlling Yersinia Virulence

    PubMed Central

    Klein, Johannes; Bücker, René; Herbst, Katharina; Heroven, Ann Kathrin; Pisano, Fabio; Wittmann, Christoph; Münch, Richard; Müller, Johannes; Jahn, Dieter

    2016-01-01

    Different biomolecules have been identified in bacterial pathogens that sense changes in temperature and trigger expression of virulence programs upon host entry. However, the dynamics and quantitative outcome of this response in individual cells of a population, and how this influences pathogenicity are unknown. Here, we address these questions using a thermosensing virulence regulator of an intestinal pathogen (RovA of Yersinia pseudotuberculosis) as a model. We reveal that this regulator is part of a novel thermoresponsive bistable switch, which leads to high- and low-invasive subpopulations within a narrow temperature range. The temperature range in which bistability is observed is defined by the degradation and synthesis rate of the regulator, and is further adjustable via a nutrient-responsive regulator. The thermoresponsive switch is also characterized by a hysteretic behavior in which activation and deactivation occurred on vastly different time scales. Mathematical modeling accurately mirrored the experimental behavior and predicted that the thermoresponsiveness of this sophisticated bistable switch is mainly determined by the thermo-triggered increase of RovA proteolysis. We further observed RovA ON and OFF subpopulations of Y. pseudotuberculosis in the Peyer’s patches and caecum of infected mice, and that changes in the RovA ON/OFF cell ratio reduce tissue colonization and overall virulence. This points to a bet-hedging strategy in which the thermoresponsive bistable switch plays a key role in adapting the bacteria to the fluctuating conditions encountered as they pass through the host’s intestinal epithelium and suggests novel strategies for the development of antimicrobial therapies. PMID:28006011

  9. Population structure and evolution of pathogenicity of Yersinia pseudotuberculosis.

    PubMed

    Ch'ng, Shear Lane; Octavia, Sophie; Xia, Qiuyu; Duong, An; Tanaka, Mark M; Fukushima, Hiroshi; Lan, Ruiting

    2011-02-01

    Yersinia pseudotuberculosis is an enteric human pathogen but is widespread in the environment. Pathogenicity is determined by a number of virulence factors, including the virulence plasmid pYV, the high-pathogenicity island (HPI), and the Y. pseudotuberculosis-derived mitogen (YPM), a superantigen. The presence of the 3 virulence factors varies among Y. pseudotuberculosis isolates. We developed a multilocus sequence typing (MLST) scheme to address the population structure of Y. pseudotuberculosis and the evolution of its pathogenicity. The seven housekeeping genes selected for MLST were mdh, recA, sucA, fumC, aroC, pgi, and gyrB. An MLST analysis of 83 isolates of Y. pseudotuberculosis, representing 19 different serotypes and six different genetic groups, identified 61 sequence types (STs) and 12 clonal complexes. Out of 26 allelic changes that occurred in the 12 clonal complexes, 13 were mutational events while 13 were recombinational events, indicating that recombination and mutation contributed equally to the diversification of the clonal complexes. The isolates were separated into 2 distinctive clusters, A and B. Cluster A is the major cluster, with 53 STs (including Y. pestis strains), and is distributed worldwide, while cluster B is restricted to the Far East. The YPM gene is widely distributed on the phylogenetic tree, with ypmA in cluster A and ypmB in cluster B. pYV is present in cluster A only but is sporadically absent in some cluster A isolates. In contrast, an HPI is present only in a limited number of lineages and must be gained by lateral transfer. Three STs carry all 3 virulence factors and can be regarded as high-pathogenicity clones. Isolates from the same ST may not carry all 3 virulence factors, indicating frequent gain or loss of these factors. The differences in pathogenicity among Y. pseudotuberculosis strains are likely due to the variable presence and instability of the virulence factors.

  10. Protective efficacy of PLGA microspheres loaded with divalent DNA vaccine encoding the ompA gene of Aeromonas veronii and the hly gene of Aeromonas hydrophila in mice.

    PubMed

    Gao, Shanshan; Zhao, Na; Amer, Said; Qian, Mingming; Lv, Mengxi; Zhao, Yuliang; Su, Xin; Cao, Jieying; He, Hongxuan; Zhao, Baohua

    2013-11-19

    In the present study, poly (lactic-co-glycolic) acid (PLGA) was used as a carrier for a divalent fusion DNA vaccine encoding the Aeromonas veronii outer membrane protein A (ompA) and Aeromonas hydrophila hemolysins (hly) protein. The recombinant pET-28a-ompA-hly was constructed by inserting the ompA gene and hly gene into a pET-28a expression vector. Loading of ompA-hly antigen module on PLGA microspheres were accomplished by water-in-oil-in-water (W/O/W) encapsulation. The molecular weight and specificity of pET-28a-ompA-hly were detected by dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting. The microspheres showed an average particle size of 100-150 μm and a loading efficiency (LE) of 68.8%. Mice received ompA-hly antigen-loaded PLGA microspheres by intraperitoneal or intragastric administration mounted strong and sustained IgG response, which was significantly higher (p<0.05) than those achieved by pET-28a-ompA-hly antigen alone. OmpA-hly antigen-loaded PLGA microsphere vaccine uniquely conferred a long lasting (30 days) sterile immunity against challenge infection. Results indicated that ompA-hly antigen-loaded PLGA microsphere vaccine is a qualified candidate vector system for sterile protective immunity against A. hydrophila and A. veronii infections.

  11. 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

  12. Genome Sequence of the Fish Pathogen Yersinia ruckeri Strain 150, Isolated from Diseased Rainbow Trout

    PubMed Central

    Cascales, Desirée; Guijarro, José A.; Reimundo, Pilar; García-Torrico, Ana I.

    2016-01-01

    We present here the draft genome of a pathogenic Yersinia ruckeri strain, isolated from rainbow trout (Oncorhynchus mykiss) affected by enteric redmouth disease. The chromosome has 3,826,775 bp, a GC content of 46.88%, and is predicted to contain 3,538 coding sequences. The data will be useful for comparative pathogenicity studies. PMID:27908991

  13. A mutli-omic systems approach to elucidating Yersinia virulence mechanisms

    PubMed Central

    Ansong, Charles; Schrimpe-Rutledge, Alexandra C.; Mitchell, Hugh; Chauhan, Sadhana; Jones, Marcus B.; Kim, Young-Mo; McAteer, Kathleen; Deatherage Kaiser, Brooke L.; Dubois, Jennifer L.; Brewer, Heather M.; Frank, Bryan C.; McDermott, Jason E.; Metz, Thomas O.; Peterson, Scott N.; Smith, Richard D.; Motin, Vladimir L.; Adkins, Joshua N.

    2012-01-01

    The underlying mechanisms that lead to dramatic differences between closely related pathogens are not always readily apparent. For example, the genomes of Yersinia pestis (YP) the causative agent of plague with a high mortality rate and Yersinia pseudotuberculosis (YPT) an enteric pathogen with a modest mortality rate are highly similar with some species specific differences; however the molecular causes of their distinct clinical outcomes remain poorly understood. In this study, a temporal multi-omic analysis of YP and YPT at physiologically relevant temperatures was performed to gain insights into how an acute and highly lethal bacterial pathogen, YP, differs from its less virulent progenitor, YPT. This analysis revealed higher gene and protein expression levels of conserved major virulence factors in YP relative to YPT, including the Yop virulon and the pH6 antigen. This suggests that adaptation in the regulatory architecture, in addition to the presence of unique genetic material, may contribute to the increased pathogenenicity of YP relative to YPT. Additionally, global transcriptome and proteome responses of YP and YPT revealed conserved post-transcriptional control of metabolism and the translational machinery including the modulation of glutamate levels in Yersiniae. Finally, the omics data was coupled with a computational network analysis, allowing an efficient prediction of novel Yersinia virulence factors based on gene and protein expression patterns. PMID:23147219

  14. Hfq Regulates Biofilm Gut Blockage That Facilitates Flea-Borne Transmission of Yersinia pestis

    PubMed Central

    Rempe, Katherine A.; Hinz, Angela K.

    2012-01-01

    The plague bacillus Yersinia pestis can achieve transmission by biofilm blockage of the foregut proventriculus of its flea vector. Hfq is revealed to be essential for biofilm blockage formation and acquisition and fitness of Y. pestis during flea gut infection, consistent with posttranscriptional regulatory mechanisms in plague transmission. PMID:22328669

  15. Far East Scarlet-Like Fever Caused by a Few Related Genotypes of Yersinia pseudotuberculosis, Russia.

    PubMed

    Timchenko, Nelly F; Adgamov, Ruslan R; Popov, Alexander F; Psareva, Ekaterina K; Sobyanin, Konstantin A; Gintsburg, Alexander L; Ermolaeva, Svetlana A

    2016-03-01

    We used multivirulence locus sequence typing to analyze 68 Yersinia pseudotuberculosis isolates from patients in Russia during 1973-2014, including 41 isolates from patients with Far East scarlet-like fever. Four genotypes were found responsible, with 1 being especially prevalent. Evolutionary analysis suggests that epidemiologic advantages could cause this genotype's dominance.

  16. Flagella biosynthesis and regulation by the Rcs pathway within the fish pathogen Yersinia ruckeri during infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The gram-negative Enterobacterium Yersinia ruckeri is the etiologic agent of enteric redmouth disease (ERM) within farmed rainbow trout (Oncorhynchus mykiss, Walbaum). Over the past decade, there has been an increase in the prevalence of non-motile variants of Y. ruckeri and the appearance of these ...

  17. Independent emergence of biotype 2 Yersinia ruckeri in the United States and Europe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biotype 2 (BT2) variants of the bacterium Yersinia ruckeri are an increasing disease problem in United States (US) and European aquaculture and have been characterized as serovar 1 isolates that lack peritrichous flagella and secreted phospholipase activity. The emergence of this biotype has been as...

  18. Intestinal obstruction complicating Yersinia enterocolitica serotype O:21 infection in an infant.

    PubMed

    Mufti, Areej; Al Kaabi, Nawal A; Rubin, Steven Z; Suh, Kathryn N

    2005-12-01

    Intestinal obstruction is an uncommon complication of Yersinia enterocolitica infection. We report a case of enterocolitis in an 11-month-old infant, complicated by intestinal obstruction. Y. entercolitica serotype O:21, previously reported to cause severe disease, was isolated from the patient's stool. Unusual or complicated presentations of yersiniosis may be associated with more pathogenic strains of Y. enterocolitica.

  19. Yersinia virulence factors - a sophisticated arsenal for combating host defences

    PubMed Central

    Atkinson, Steve; Williams, Paul

    2016-01-01

    The human pathogens Yersinia pseudotuberculosis and Yersinia enterocolitica cause enterocolitis, while Yersinia pestis is responsible for pneumonic, bubonic, and septicaemic plague. All three share an infection strategy that relies on a virulence factor arsenal to enable them to enter, adhere to, and colonise the host while evading host defences to avoid untimely clearance. Their arsenal includes a number of adhesins that allow the invading pathogens to establish a foothold in the host and to adhere to specific tissues later during infection. When the host innate immune system has been activated, all three pathogens produce a structure analogous to a hypodermic needle. In conjunction with the translocon, which forms a pore in the host membrane, the channel that is formed enables the transfer of six ‘effector’ proteins into the host cell cytoplasm. These proteins mimic host cell proteins but are more efficient than their native counterparts at modifying the host cell cytoskeleton, triggering the host cell suicide response. Such a sophisticated arsenal ensures that yersiniae maintain the upper hand despite the best efforts of the host to counteract the infecting pathogen. PMID:27347390

  20. Shotgun genome sequence of a Yersinia enterocolitica isolate from the Philippines.

    PubMed

    Klinzing, David C; Matias, Ronald R; Skowronski, Evan; Alvarez, May; Liles, Veni; Dimamay, Mark Pierre; Natividad, Filipinas F

    2012-01-01

    The first shotgun genome sequence of a microbial pathogen from the Philippines is reported. Yersinia enterocolitica subsp. palearctica strain PhRBD_Ye1 is the first Y. enterocolitica strain sequenced from an animal source, swine, which is a natural source of yersiniosis. The closest phylogenetic match is a human clinical isolate from Germany.

  1. Shotgun Genome Sequence of a Yersinia enterocolitica Isolate from the Philippines

    PubMed Central

    Matias, Ronald R.; Skowronski, Evan; Alvarez, May; Liles, Veni; Dimamay, Mark Pierre; Natividad, Filipinas F.

    2012-01-01

    The first shotgun genome sequence of a microbial pathogen from the Philippines is reported. Yersinia enterocolitica subsp. palearctica strain PhRBD_Ye1 is the first Y. enterocolitica strain sequenced from an animal source, swine, which is a natural source of yersiniosis. The closest phylogenetic match is a human clinical isolate from Germany. PMID:22207747

  2. Genome assemblies for 11 Yersinia pestis strains isolated in the Caucasus region

    DOE PAGES

    Zhgenti, Ekaterine; Johnson, Shannon L.; Davenport, Karen W.; ...

    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.

  3. 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.

  4. Inactivation of avirulent pgm+ and delta pgm Yersinia pestis by ultraviolet light (UV-C)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yersinia pestis is the causative agent of bubonic plague. Though not considered a foodborne pathogen, Y. pestis can survive, and even grow, in some foods, and the foodborne route of transmission is not without precedent. As such, concerns exist over the possible intentional contamination of foods wi...

  5. 76 FR 69034 - Microbiology Devices; Classification of In Vitro Diagnostic Device for Yersinia Species Detection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ... specimens as an aid in the diagnosis of plague and other diseases caused by Yersinia spp. This device may... three different forms of plague (bubonic, pneumonic, and septicemic), caused by Y. pestis, and... treatment, as well as inaccurate epidemiological information on the presence of plague disease in...

  6. Inactivation of avirulent Yersinia pestis in beef bologna by gamma irradiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yersinia pestis, a psychrotrophic pathogen capable of growth at refrigeration temperatures, can cause pharyngeal and gastrointestinal plague in humans as a result of eating contaminated foods. Because Y. pestis is listed as a select agent for food safety and defense, evaluation of food safety interv...

  7. Inactivation of avirulent Yersinia pestis on food and food contact surfaces by ultraviolet light and freezing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yersinia pestis, the causative agent of plague, can occasionally be contracted as a naso-pharangeal or gastrointestinal illness through consumption of contaminated meat. In this study, the use of 254 nm ultraviolet light (UV-C) to inactivate a multi-isolate cocktail of avirulent Y. pestis on food an...

  8. Far East Scarlet-Like Fever Caused by a Few Related Genotypes of Yersinia pseudotuberculosis, Russia

    PubMed Central

    Timchenko, Nelly F.; Adgamov, Ruslan R.; Popov, Alexander F.; Psareva, Ekaterina K.; Sobyanin, Konstantin A.; Gintsburg, Alexander L.

    2016-01-01

    We used multivirulence locus sequence typing to analyze 68 Yersinia pseudotuberculosis isolated in Russia during 1973–2014, including 41 isolates from patients with Far East scarlet-like fever. Four genotypes were found responsible, with 1 being especially prevalent. Evolutionary analysis suggests that epidemiologic advantages could cause this genotype’s dominance. PMID:26889961

  9. Yersinia virulence factors - a sophisticated arsenal for combating host defences.

    PubMed

    Atkinson, Steve; Williams, Paul

    2016-01-01

    The human pathogens Yersinia pseudotuberculosis and Yersinia enterocolitica cause enterocolitis, while Yersinia pestis is responsible for pneumonic, bubonic, and septicaemic plague. All three share an infection strategy that relies on a virulence factor arsenal to enable them to enter, adhere to, and colonise the host while evading host defences to avoid untimely clearance. Their arsenal includes a number of adhesins that allow the invading pathogens to establish a foothold in the host and to adhere to specific tissues later during infection. When the host innate immune system has been activated, all three pathogens produce a structure analogous to a hypodermic needle. In conjunction with the translocon, which forms a pore in the host membrane, the channel that is formed enables the transfer of six 'effector' proteins into the host cell cytoplasm. These proteins mimic host cell proteins but are more efficient than their native counterparts at modifying the host cell cytoskeleton, triggering the host cell suicide response. Such a sophisticated arsenal ensures that yersiniae maintain the upper hand despite the best efforts of the host to counteract the infecting pathogen.

  10. Yersinia enterocolitica Outbreak Associated with Ready-to-Eat Salad Mix, Norway, 2011

    PubMed Central

    Heier, Berit Tafjord; Nygård, Karin; Stalheim, Torunn; Cudjoe, Kofitsyo S.; Skjerdal, Taran; Wester, Astrid Louise; Lindstedt, Bjørn-Arne; Stavnes, Trine-Lise; Vold, Line

    2012-01-01

    In 2011, an outbreak of illness caused by Yersinia enterocolitica O:9 in Norway was linked to ready-to-eat salad mix, an unusual vehicle for this pathogen. The outbreak illustrates the need to characterize isolates of this organism, and reinforces the need for international traceback mechanisms for fresh produce. PMID:22932318

  11. Prevalence, serotype, virulence characteristics, clonality and antibiotic susceptibility of pathogenic Yersinia enterocolitica from swine feces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Swine are the only known animal reservoir of Yersinia enterocolitica (YE), a human pathogen. Since YE is a fecal organism of swine, the primary goal of this study was to evaluate the prevalence, serotype, virulence plasmid (pYV)-associated characteristics, clonality, and antibiotic su...

  12. Combined detection and strain typing of Yersinia enterocolitica directly from pork and poultry enrichments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Yersinia enterocolitica is responsible for an estimated 98,000 cases of foodborne illness per year in the U.S. causing both intestinal and extraintestinal diseases. Its prevalence in retail pork and poultry, believed to the primary sources of these infections, ranges widely from 0 to 6...

  13. Clonality and Antibiotic Susceptibility of Yersinia enterocolitica Isolated From U.S. Market Weight Hogs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pigs are the only known animal reservoir of Yersinia enterocolitica pathogenic to humans. In this study 106 ail-positive pathogenic Y. enterocolitica isolates, previously recovered from 2,793 swine fecal samples (3.8%) collected during National Animal Health Monitoring System’s Swine 2000 study, wer...

  14. Yersinia enterocolitica outbreak associated with ready-to-eat salad mix, Norway, 2011.

    PubMed

    MacDonald, Emily; Heier, Berit Tafjord; Nygård, Karin; Stalheim, Torunn; Cudjoe, Kofitsyo S; Skjerdal, Taran; Wester, Astrid Louise; Lindstedt, Bjørn-Arne; Stavnes, Trine-Lise; Vold, Line

    2012-09-01

    In 2011, an outbreak of illness caused by Yersinia enterocolitica O:9 in Norway was linked to ready-to-eat salad mix, an unusual vehicle for this pathogen. The outbreak illustrates the need to characterize isolates of this organism, and reinforces the need for international traceback mechanisms for fresh produce.

  15. Complete Genome Sequence of Pigmentation-Negative Yersinia pestis Strain Cadman

    PubMed Central

    Lovett, Sean; Chase, Kitty; Koroleva, Galina; Palacios, Gustavo; Ladner, Jason T.

    2016-01-01

    Here, we report the genome sequence of Yersinia pestis strain Cadman, an attenuated strain lacking the pgm locus. Y. pestis is the causative agent of plague and generally must be worked with under biosafety level 3 (BSL-3) conditions. However, strains lacking the pgm locus are considered safe to work with under BSL-2 conditions. PMID:27789646

  16. Detection, seroprevalence and antimicrobial resistance of Yersinia enterocolitica and Yersinia pseudotuberculosis in pig tonsils in Northern Italy.

    PubMed

    Bonardi, S; Bruini, I; D'Incau, M; Van Damme, I; Carniel, E; Brémont, S; Cavallini, P; Tagliabue, S; Brindani, F

    2016-10-17

    Yersiniosis is the third most common reported zoonoses in Europe, with Y. enterocolitica and Y. pseudotuberculosis responsible for 98.66% and 0.94% of the confirmed human cases in 2013. From June 2013 to October 2014, 201 pigs at slaughter belonging to 67 batches were tested for Y. enterocolitica and Y. pseudotuberculosis in tonsils. Diaphragm muscle samples were tested for antibodies against Yersinia by a commercially available ELISA test. Y. enterocolitica 4/O:3 was detected in 55/201 pig tonsils (27.4%; 95% CI 23.1-37.1). The positive pigs came from 38/67 batches (56.7%) and were reared in 36/61 farms (59.0%). There was no statistical difference between farrow-to-finish and finishing farms. The mean count of Y. enterocolitica was 3.56±0.85log10CFU/g with a minimum of 2.0log10CFU/g and a maximum of 4.78log10CFU/g. Y. pseudotuberculosis was isolated from 4/201 pig tonsils (2.0%; 95% CI 0.0-4.5). Three isolates belonged to serotype O:3 and one to serotype O:1. The positive pigs belonged to 4/67 batches (6.0%) and came from finishing farms only. Y. pseudotuberculosis could be enumerated in one sample only (4.27log10CFU/g). The ELISA test demonstrated that 56.1% of the meat juice samples were positive for Yersinia antibodies. Serological positivity was found in 67.9% (36/53) of the Y. enterocolitica- and 75.0% (3/4) of the Y. pseudotuberculosis positive pigs. A significant association was found between serological results and the presence of Y. enterocolitica in tonsils (OR=1.97, p=0.044). All the Y. enterocolitica 4/O:3 isolates were susceptible to amoxicillin-clavulanic acid, gentamicin, ceftazidime, ertapenem and meropenem, 94.5% to cefotaxime, 89.1% to kanamycin and 78.2% to tetracycline. The highest resistance rates were observed for ampicillin (100%), sulphonamides (98.2%) and streptomycin (78.2%). Y. pseudotuberculosis strains were sensitive to all the antimicrobials tested, i.e. amoxicillin, amoxicillin/clavulanic acid, azithromycin, cephalothin, cefoxitin

  17. Development and application of real-time PCR assays for quantifying total and aerolysin gene-containing aeromonas in source, intermediate, and finished drinking water.

    PubMed

    Yu, Chang-Ping; Farrell, Sara K; Robinson, Bruce; Chu, Kung-Hui

    2008-02-15

    Aeromonas spp., opportunistic pathogens, are listed as a microbiological contaminant on the Environmental Protection Agency's (EPA) Drinking Water Contaminant Candidate List. Culture-based methods for identification and quantification of Aeromonas in drinking water are time-consuming and often fail to differentiate pathogenic species from nonpathogenic ones. This study reports successful development and applications of two real-time PCR assays, based on 16S rRNA gene sequences and a virulence gene (aerolysin gene), for rapid and effective quantification of total and aerolysin gene-containing Aeromonas spp. The assays successfully quantified total and aerolysin gene-containing Aeromonas in source, intermediate, and finished water samples collected from seven water works and one pilot plant. The effectiveness of Aeromonas removal by different drinking water treatment processes was examined by comparing the results obtained from the EPA culture-based method and developed real-time PCR assays. Regardless of the methods, our results indicated that conventional water treatment combination (prechlorination/ coagulation/sedimentation/rapid sand filtration) and membrane filtration alone could effectively remove Aeromonas. Slow sand filtration alone might not be effective. The removal efficiencies by different disinfection treatments were not determined, due to the lack of detectable Aeromonas. No Aeromonas was detected in samples with turbidity below 0.06 NTU.

  18. 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...

  19. Characterization of genetic determinants involved in antibiotic resistance in Aeromonas spp. and fecal coliforms isolated from different aquatic environments.

    PubMed

    Carnelli, Alessandro; Mauri, Federica; Demarta, Antonella

    2017-03-02

    Aeromonas spp. and fecal coliforms, two abundant and cultivable bacterial populations that can be found in water ecosystems, might substantially contribute to the spread of antibiotic resistance. We investigated the presence and spread of transposons (elements that can move from one location to another in the genome), integrons (structures able to capture and incorporate gene cassettes) and resistance plasmids in strains isolated from polluted and unpolluted water. We recovered 231 Aeromonas and 250 fecal coliforms from water samplings with different degrees of pollution (hospital sewage, activated sludge of a wastewater treatment plant, river water before and after treatment and water from an alpine lake). Sixteen Aeromonas spp. and 22 fecal coliforms carried intI, coding for the site-specific integrase of class 1 integrons, while 22 Aeromonas spp. and 14 fecal coliforms carried tnpA, the transposase gene of the Tn3-family of replicative transposons. The majority of intI and tnpA-positive strains were phenotypically resistant to at least four antibiotics. Integrons and transposons were mainly located on mobilizable plasmids. Our results did not detect common mobile structures in the two populations and therefore relativize the role played by Aeromonas spp. as vectors of antimicrobial resistance determinants between water and commensal gut bacteria.

  20. Presence of Aeromonas spp in water from drinking-water- and wastewater-treatment plants in Mexico City.

    PubMed

    Villarruel-López, Angélica; Fernández-Rendón, Elizabeth; Mota-de-la-Garza, Lydia; Ortigoza-Ferado, Jorge

    2005-01-01

    The frequency of Aeromonas spp in three wastewater-treatment plants (WWTPs) and two drinking-water plants (DWPs) in México City was determined. Samples were taken throughout a year by the Moore's swab technique. A total of 144 samples were obtained from WWTPs and 96 from DWPs of both incoming and outflowing water. Aeromonas spp was isolated in 31% of the samples, from both kinds of sources. The technique used for the isolation of the pathogen was suitable for samples with high associate microbiota content and for those with a scarce microbial content. The presence of mesophilic-aerobic, coliform, and fecal-coliform organisms was investigated to determine whether there was any correlation with the presence of Aeromonas spp. Most samples from WWTP, which did not comply with the Mexican standards, had the pathogen, and some of the samples from the outflow of the DWP, which were within the limits set by the Mexican standards, also had Aeromonas spp. Most samples containing Aeromonas spp. had concentrations below 0.1 ppm residual chlorine, and the strains were resistant to 0.3 ppm, which supports the recommendation to increase the residual chlorine concentration to 0.5 to 1.0 ppm, as recommended by the Mexican standards.

  1. Subcellular proteomic analysis of host-pathogen interactions using human monocytes exposed to Yersinia pestis and Yersinia pseudotuberculosis

    SciTech Connect

    Zhang, C G; Gonzales, A D; Choi, M W; Chromy, B A; Fitch, J P; McCutchen-Maloney, S L

    2004-05-20

    Yersinia pestis, the etiological agent of plague, is of concern to human health both from an infectious disease and a civilian biodefense perspective. While Y. pestis and Y. pseudotuberculosis share more than 90% DNA homology, they have significantly different clinical manifestations. Plague is often fatal if untreated, yet Y. pseudotuberculosis causes severe intestinal distress and is rarely fatal. A better understanding of host response to these closely related pathogens may help explain the different mechanisms of virulence and pathogenesis that result in such different clinical outcomes. The aim of this study was to characterize host protein expression changes in human monocyte-like U937 cells after exposure to Y. pestis and Y. pseudotuberculosis. In order to gain global proteomic coverage of host response, proteins from cytoplasmic, nuclear and membrane fractions of host cells were studied by 2-dimensional differential gel electrophoresis (2-D DIGE) and relative protein expression differences were quantitated. Differentially expressed proteins, with at least 1.5 fold expression changes and p values of 0.01 or less, were identified by MALDI-MS or LC/MS/MS. With these criteria, differential expression was detected in 16 human proteins after Y. pestis exposure and 13 human proteins after Y. pseudotuberculosis exposure, of which only two of the differentially expressed proteins identified were shared between the two exposures. Proteins identified in this study are reported to be involved in a wide spectrum of cellular functions and host defense mechanisms including apoptosis, cytoskeletal rearrangement, protein synthesis and degradation, DNA replication and transcription, metabolism, protein folding, and cell signaling. Notably, the differential expression patterns observed can distinguish the two pathogen exposures from each other and from unexposed host cells. The functions of the differentially expressed proteins identified provide insight on the different

  2. Evaluation of different enrichment methods for pathogenic Yersinia species detection by real time PCR

    PubMed Central

    2014-01-01

    Background Yersiniosis is a zoonotic disease reported worldwide. Culture and PCR based protocols are the most common used methods for detection of pathogenic Yersinia species in animal samples. PCR sensitivity could be increased by an initial enrichment step. This step is particularly useful in surveillance programs, where PCR is applied to samples from asymptomatic animals. The aim of this study was to evaluate the improvement in pathogenic Yersinia species detection using a suitable enrichment method prior to the real time PCR (rtPCR). Nine different enrichment protocols were evaluated including six different broth mediums (CASO, ITC, PSB, PBS, PBSMSB and PBSSSB). Results The analysis of variance showed significant differences in Yersinia detection by rtPCR according to the enrichment protocol used. These differences were higher for Y. pseudotuberculosis than for Y. enterocolitica. In general, samples incubated at lower temperatures yielded the highest detection rates. The best results were obtained with PBSMSB and PBS2. Application of PBSMSB protocol to free-ranging wild board samples improved the detection of Y. enterocolitica by 21.2% when compared with direct rtPCR. Y. pseudotuberculosis detection was improved by 10.6% when results obtained by direct rtPCR and by PBSMSB enrichment before rtPCR were analyzed in combination. Conclusions The data obtained in the present study indicate a difference in Yersinia detection by rtPCR related to the enrichment protocol used, being PBSMSB enrichment during 15 days at 4°C and PBS during 7 days at 4°C the most efficient. The use of direct rtPCR in combination with PBSMSB enrichment prior to rtPCR resulted in an improvement in the detection rates of pathogenic Yersinia in wild boar and could be useful for application in other animal samples. PMID:25168886

  3. Expression of the Plague Plasminogen Activator in Yersinia pseudotuberculosis and Escherichia coli

    PubMed Central

    Kutyrev, V.; Mehigh, R. J.; Motin, V. L.; Pokrovskaya, M. S.; Smirnov, G. B.; Brubaker, R. R.

    1999-01-01

    Enteropathogenic yersiniae (Yersinia pseudotuberculosis and Yersinia enterocolitica) typically cause chronic disease as opposed to the closely related Yersinia pestis, the causative agent of bubonic plague. It is established that this difference reflects, in part, carriage by Y. pestis of a unique 9.6-kb pesticin or Pst plasmid (pPCP) encoding plasminogen activator (Pla) rather than distinctions between shared ∼70-kb low-calcium-response, or Lcr, plasmids (pCD in Y. pestis and pYV in enteropathogenic yersiniae) encoding cytotoxic Yops and anti-inflammatory V antigen. Pla is known to exist as a combination of 32.6-kDa (α-Pla) and slightly smaller (β-Pla) outer membrane proteins, of which at least one promotes bacterial dissemination in vivo and degradation of Yops in vitro. We show here that only α-Pla accumulates in Escherichia coli LE392/pPCP1 cultivated in enriched medium and that either autolysis or extraction of this isolate with 1.0 M NaCl results in release of soluble α and β forms possessing biological activity. This process also converted cell-bound α-Pla to β-Pla and smaller forms in Y. pestis KIM/pPCP1 and Y. pseudotuberculosis PB1/+/pPCP1 but did not promote solubilization. Pla-mediated posttranslational hydrolysis of pulse-labeled Yops in Y. pseudotuberculosis PB1/+/pPCP1 occurred more slowly than that in Y. pestis but was otherwise similar except for accumulation of stable degradation products of YadA, a pYV-mediated fibrillar adhesin not encoded in frame by pCD. Carriage of pPCP by Y. pseudotuberculosis did not significantly influence virulence in mice. PMID:10024583

  4. Hunger for iron: the alternative siderophore iron scavenging systems in highly virulent Yersinia.

    PubMed

    Rakin, Alexander; Schneider, Lukas; Podladchikova, Olga

    2012-01-01

    Low molecular weight siderophores are used by many living organisms to scavenge scarcely available ferric iron. Presence of at least a single siderophore-based iron acquisition system is usually acknowledged as a virulence-associated trait and a pre-requisite to become an efficient and successful pathogen. Currently, it is assumed that yersiniabactin (Ybt) is the solely functional endogenous siderophore iron uptake system in highly virulent Yersinia (Yersinia pestis, Y. pseudotuberculosis, and Y. enterocolitica biotype 1B). Genes responsible for biosynthesis, transport, and regulation of the yersiniabactin (ybt) production are clustered on a mobile genetic element, the High-Pathogenicity Island (HPI) that is responsible for broad dissemination of the ybt genes in Enterobacteriaceae. However, the ybt gene cluster is absent from nearly half of Y. pseudotuberculosis O3 isolates and epidemic Y. pseudotuberculosis O1 isolates responsible for the Far East Scarlet-like Fever. Several potential siderophore-mediated iron uptake gene clusters are documented in Yersinia genomes, however, neither of them have been proven to be functional. It has been suggested that at least two siderophores alternative to Ybt may operate in the highly virulent Yersinia pestis/Y. pseudotuberculosis group, and are referred to as pseudochelin (Pch) and yersiniachelin (Ych). Furthermore, most sporadic Y. pseudotuberculosis O1 strains possess gene clusters encoding all three iron scavenging systems. Thus, the Ybt system appears not to be the sole endogenous siderophore iron uptake system in the highly virulent yersiniae and may be efficiently substituted and/or supplemented by alternative iron siderophore scavenging systems.

  5. Yersinia enterocolitica, a Neglected Cause of Human Enteric Infections in Côte d’Ivoire

    PubMed Central

    Saraka, Daniel; Savin, Cyril; Kouassi, Stephane; Cissé, Bakary; Koffi, Eugène; Cabanel, Nicolas; Brémont, Sylvie; Faye-Kette, Hortense; Dosso, Mireille; Carniel, Elisabeth

    2017-01-01

    Background Enteropathogenic Yersinia circulate in the pig reservoir and are the third bacterial cause of human gastrointestinal infections in Europe. In West Africa, reports of human yersiniosis are rare. This study was conducted to determine whether pathogenic Yersinia are circulating in pig farms and are responsible for human infections in the Abidjan District. Methodology/Principal findings From June 2012 to December 2013, pig feces were collected monthly in 41 swine farms of the Abidjan district. Of the 781 samples collected, 19 Yersinia strains were isolated in 3 farms: 7 non-pathogenic Yersinia intermedia and 12 pathogenic Yersinia enterocolitica bioserotype 4/O:3. Farm animals other than pigs and wild animals were not found infected. Furthermore, 2 Y. enterocolitica 4/O:3 strains were isolated from 426 fecal samples of patients with digestive disorders. All 14 Y. enterocolitica strains shared the same PFGE and MLVA profile, indicating their close genetic relationship. However, while 6 of them displayed the usual phage type VIII, the other 8 had the highly infrequent phage type XI. Whole genome sequencing and SNP analysis of individual colonies revealed that phage type XI strains had unusually high rates of mutations. These strains displayed a hypermutator phenotype that was attributable to a large deletion in the mutS gene involved in DNA mismatch repair. Conclusions/Significance This study demonstrates that pathogenic Y. enterocolitica circulate in the pig reservoir in Côte d'Ivoire and cause human infections with a prevalence comparable to that of many developed countries. The paucity of reports of yersiniosis in West Africa is most likely attributable to a lack of active detection rather than to an absence of the microorganism. The identification of hypermutator strains in pigs and humans is of concern as these strains can rapidly acquire selective advantages that may increase their fitness, pathogenicity or resistance to commonly used treatments. PMID

  6. Quinolone resistant Aeromonas spp. as carriers and potential tracers of acquired antibiotic resistance in hospital and municipal wastewater.

    PubMed

    Varela, Ana Rita; Nunes, Olga C; Manaia, Célia M

    2016-01-15

    Members of the genus Aeromonas are recognized carriers of antibiotic resistance in aquatic environments. However, their importance on the spread of resistance from hospital effluents to the environment is poorly understood. Quinolone resistant Aeromonas spp. (n = 112) isolated from hospital effluent (HE) and from raw (RWW) and treated wastewater (TWW) of the receiving urban wastewater treatment plant (UWTP) were characterized. Species identification and genetic intraspecies diversity were assessed based on the 16S rRNA, cpn60 and gyrB genes sequence analysis. The antibiotic resistance phenotypes and genotypes (qnrA, qnrB, qnrC, qnrD, qnrS, qnrVC; qepA; oqxAB; aac(6′)-Ib-cr; blaOXA; incU) were analyzed in function of the origin and taxonomic group. Most isolates belonged to the species Aeromonas caviae and Aeromonas hydrophila (50% and 41%, respectively). The quinolone and the beta-lactamase resistance genes aac(6′)-Ib-cr and blaOXA, including gene blaOXA-101, identified for the first time in Aeromonas spp., were detected in 58% and 56% of the isolates, respectively, with identical prevalence in HE and UWTP wastewater. In contrast, the gene qnrS2 was observed mainly in isolates from the UWTP (51%) and rarely in HE isolates (3%), suggesting that its origin is not the clinical setting. Bacterial groups and genes that allow the identification of major routes of antibiotic resistance dissemination are valuable tools to control this problem. In this study, it was concluded that members of the genus Aeromonas harboring the genes aac(6′)-Ib-cr and blaOXA are relevant tracers of antibiotic resistance dissemination in wastewater habitats, while those yielding the gene qnrS2 allow the traceability from non-clinical sources.

  7. 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

  8. Dropped head syndrome in a patient with Aeromonas hydrophila-induced septic arthritis of the shoulder.

    PubMed

    Wang, Sheng-Huei; Juan, Chun-Jung; Lin, Te-Yu

    2014-12-01

    Septic arthritis of the shoulder is very rarely caused by Aeromonas hydrophila. We present the case of a 45-year-old woman who presented with symptoms of painful shoulder for 2 weeks and dropped head for 1 week prior to admission. A. hydrophila was isolated from a culture of purulent synovial fluid. Magnetic resonance imaging revealed profuse abscess collection between the right infraspinatus muscle and trapezius muscle and swelling of the right and left paraspinatus muscles, which suggested myositis-related dropped head syndrome. After surgery with arthrotomy, function of the shoulder and neck extensors was significantly improved.

  9. Virulence factors-pathogenicity relationships for Aeromonas species from clinical and food isolates.

    PubMed

    Pin, C; Morales, P; Marín, M L; Selgas, M D; García, M L; Casas, C

    1997-01-01

    The presence of virulence factors in 96 Aeromonas strains isolated from food and clinical samples was studied. Neither cytotoxic activity and hydrophobicity, not the presence of pili or an extra surface layer made it possible to establish differences between food and clinical strains. Statistical studies showed that cytotoxin production was associated with a positive Voges-Proskauer reaction, inability to ferment arabinose and a positive lysine decarboxylation. Therefore, when comparing cytotoxic clinical and food strains with lysine decarboxylation phenotype, there was a significant difference (p < 0.05) between the two groups. The association of a cytotoxin production and lysine decarboxylation character should thus be considered as a possible virulence marker.

  10. Evaluation of the Role of the opgGH Operon in Yersinia pseudotuberculosis and Its Deletion during the Emergence of Yersinia pestis.

    PubMed

    Quintard, Kévin; Dewitte, Amélie; Reboul, Angéline; Madec, Edwige; Bontemps-Gallo, Sébastien; Dondeyne, Jacqueline; Marceau, Michaël; Simonet, Michel; Lacroix, Jean-Marie; Sebbane, Florent

    2015-09-01

    The opgGH operon encodes glucosyltransferases that synthesize osmoregulated periplasmic glucans (OPGs) from UDP-glucose, using acyl carrier protein (ACP) as a cofactor. OPGs are required for motility, biofilm formation, and virulence in various bacteria. OpgH also sequesters FtsZ in order to regulate cell size according to nutrient availability. Yersinia pestis (the agent of flea-borne plague) lost the opgGH operon during its emergence from the enteropathogen Yersinia pseudotuberculosis. When expressed in OPG-negative strains of Escherichia coli and Dickeya dadantii, opgGH from Y. pseudotuberculosis restored OPGs synthesis, motility, and virulence. However, Y. pseudotuberculosis did not produce OPGs (i) under various growth conditions or (ii) when overexpressing its opgGH operon, its galUF operon (governing UDP-glucose), or the opgGH operon or Acp from E. coli. A ΔopgGH Y. pseudotuberculosis strain showed normal motility, biofilm formation, resistance to polymyxin and macrophages, and virulence but was smaller. Consistently, Y. pestis was smaller than Y. pseudotuberculosis when cultured at ≥ 37°C, except when the plague bacillus expressed opgGH. Y. pestis expressing opgGH grew normally in serum and within macrophages and was fully virulent in mice, suggesting that small cell size was not advantageous in the mammalian host. Lastly, Y. pestis expressing opgGH was able to infect Xenopsylla cheopis fleas normally. Our results suggest an evolutionary scenario whereby an ancestral Yersinia strain lost a factor required for OPG biosynthesis but kept opgGH (to regulate cell size). The opgGH operon was presumably then lost because OpgH-dependent cell size control became unnecessary.

  11. Evaluation of the Role of the opgGH Operon in Yersinia pseudotuberculosis and Its Deletion during the Emergence of Yersinia pestis

    PubMed Central

    Quintard, Kévin; Dewitte, Amélie; Reboul, Angéline; Madec, Edwige; Bontemps-Gallo, Sébastien; Dondeyne, Jacqueline; Marceau, Michaël; Simonet, Michel

    2015-01-01

    The opgGH operon encodes glucosyltransferases that synthesize osmoregulated periplasmic glucans (OPGs) from UDP-glucose, using acyl carrier protein (ACP) as a cofactor. OPGs are required for motility, biofilm formation, and virulence in various bacteria. OpgH also sequesters FtsZ in order to regulate cell size according to nutrient availability. Yersinia pestis (the agent of flea-borne plague) lost the opgGH operon during its emergence from the enteropathogen Yersinia pseudotuberculosis. When expressed in OPG-negative strains of Escherichia coli and Dickeya dadantii, opgGH from Y. pseudotuberculosis restored OPGs synthesis, motility, and virulence. However, Y. pseudotuberculosis did not produce OPGs (i) under various growth conditions or (ii) when overexpressing its opgGH operon, its galUF operon (governing UDP-glucose), or the opgGH operon or Acp from E. coli. A ΔopgGH Y. pseudotuberculosis strain showed normal motility, biofilm formation, resistance to polymyxin and macrophages, and virulence but was smaller. Consistently, Y. pestis was smaller than Y. pseudotuberculosis when cultured at ≥37°C, except when the plague bacillus expressed opgGH. Y. pestis expressing opgGH grew normally in serum and within macrophages and was fully virulent in mice, suggesting that small cell size was not advantageous in the mammalian host. Lastly, Y. pestis expressing opgGH was able to infect Xenopsylla cheopis fleas normally. Our results suggest an evolutionary scenario whereby an ancestral Yersinia strain lost a factor required for OPG biosynthesis but kept opgGH (to regulate cell size). The opgGH operon was presumably then lost because OpgH-dependent cell size control became unnecessary. PMID:26150539

  12. Rapid Identification of Yersinia enterocolitica in Blood by the 5′ Nuclease PCR Assay

    PubMed Central

    Sen, Keya

    2000-01-01

    Yersinia enterocolitica accounts for 50% of the clinical sepsis episodes caused by the transfusion of contaminated red blood cells. A 5′ nuclease TaqMan PCR assay was developed to detect Y. enterocolitica in blood. Primers and a probe based on the nucleotide sequence of the 16S rRNA gene from Y. enterocolitica were designed. Whole-blood samples were spiked with various numbers of Y. enterocolitica cells, and total chromosomal DNA was extracted. When the TaqMan PCR assay was performed, as few as six bacteria spiked in 200 μl of blood could be detected. The assay was specific and did not detect other Yersinia species. The TaqMan assay is easy to perform, takes 2 h, and has the potential for use in the rapid detection of Y. enterocolitica contamination in stored blood units. PMID:10790127

  13. Detection of pathogenic Yersinia enterocolitica in pet Djungarian hamsters in Japan

    PubMed Central

    KAMEYAMA, Mitsuhiro; YABATA, Junko; OBANE, Noriko; OTSUKA, Hitoshi; NOMURA, Yasuharu

    2016-01-01

    The prevalence of Yersinia enterocolitica (Y. enterocolitica) and Yersinia pseudotuberculosis was examined in 151 pet animals including 108 rodents, 39 rabbits and four sugar gliders from 13 pet stores in the Yamaguchi Prefecture, Japan. Y. enterocolitica serogroup O:3 biotype 3 negative for the Voges-Proskauer reaction (O:3/3 variant VP-) was isolated from five Djungarian hamsters (Phodopus sungorus) raised at the same pet store. These pathogenic Y. enterocolitica isolates carried the virulence genes, yadA, ail and virF, and were shown to be clonal by pulsed-field gel electrophoresis with NotI digestion. This is a first report of pathogenic Y. enterocolitica O:3/3 variant VP- in pet Djungarian hamsters in Japan. PMID:27396397

  14. Translational regulation of Yersinia enterocolitica mRNA encoding a type III secretion substrate.

    PubMed

    Kopaskie, Karyl S; Ligtenberg, Katherine Given; Schneewind, Olaf

    2013-12-06

    Yersinia enterocolitica type III secretion machines transport YopQ and other Yop effectors into host immune cells. YopD and its chaperone LcrH are essential components of the Yersinia type III pathway, enabling effector translocation into host cells. YopD, LcrH, and YscM1 also regulate yop expression post-transcriptionally in response to environmental signals; however, the molecular mechanisms for this regulation and Yop secretion are unknown. We show here that YopD associates with 30 S ribosomal particles in a manner requiring LcrH. When added to ribosomes, YopD, LcrH, and YscM1 block the translation of yopQ mRNA. We propose a model whereby LcrH-dependent association of YopD with 30 S ribosomal particles enables YscM1 to block yopQ translation unless type III machines are induced to secrete the effector.

  15. Pathogenic Yersinia enterocolitica O:3 isolated from a hunted wild alpine ibex.

    PubMed

    Joutsen, S; Sarno, E; Fredriksson-Ahomaa, M; Cernela, N; Stephan, R

    2013-03-01

    Occurrence of Yersinia spp. in wild ruminants was studied and the strains were characterized to get more information on the epidemiology of enteropathogenic Yersinia in the wildlife. In total, faecal samples of 77 red deer, 60 chamois, 55 roe deer and 27 alpine ibex were collected during 3 months of the hunting season in 2011. The most frequently identified species was Y. enterocolitica found in 13%, 10%, 4% and 2% of roe deer, red deer, alpine ibex and chamois, respectively. Interestingly, one Y. enterocolitica O:3 strain, isolated from an alpine ibex, carried the important virulence genes located on the virulence plasmid (yadA and virF) and in the chromosome (ail, hreP, myfA and ystA). Most of the Y. enterocolitica strains belonged to biotype 1A of which 14 were ystB positive. Further studies are needed to clarify the importance of alpine ibex as a reservoir of pathogenic Y. enterocolitica.

  16. Retracing the evolutionary path that led to flea-borne transmission of Yersinia pestis.

    PubMed

    Sun, Yi-Cheng; Jarrett, Clayton O; Bosio, Christopher F; Hinnebusch, B Joseph

    2014-05-14

    Yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from Yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. This radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. Here, we determined the genetic and mechanistic basis of the evolutionary adaptation of Y. pestis to flea-borne transmission. Remarkably, only four minor changes in the bacterial progenitor, representing one gene gain and three gene losses, enabled transmission by flea vectors. All three loss-of-function mutations enhanced cyclic-di-GMP-mediated bacterial biofilm formation in the flea foregut, which greatly increased transmissibility. Our results suggest a step-wise evolutionary model in which Y. pestis emerged as a flea-borne clone, with each genetic change incrementally reinforcing the transmission cycle. The model conforms well to the ecological theory of adaptive radiation.

  17. Yersinia pseudotuberculosis disrupts intestinal barrier integrity through hematopoietic TLR-2 signaling

    PubMed Central

    Jung, Camille; Meinzer, Ulrich; Montcuquet, Nicolas; Thachil, Elodie; Château, Danielle; Thiébaut, Raphaële; Roy, Maryline; Alnabhani, Ziad; Berrebi, Dominique; Dussaillant, Monique; Pedruzzi, Eric; Thenet, Sophie; Cerf-Bensussan, Nadine; Hugot, Jean-Pierre; Barreau, Frederick

    2012-01-01

    Intestinal barrier function requires intricate cooperation between intestinal epithelial cells and immune cells. Enteropathogens are able to invade the intestinal lymphoid tissue known as Peyer’s patches (PPs) and disrupt the integrity of the intestinal barrier. However, the underlying molecular mechanisms of this process are poorly understood. In mice infected with Yersinia pseudotuberculosis, we found that PP barrier dysfunction is dependent on the Yersinia virulence plasmid and the expression of TLR-2 by hematopoietic cells, but not by intestinal epithelial cells. Upon TLR-2 stimulation, Y. pseudotuberculosis–infected monocytes activated caspase-1 and produced IL-1β. In turn, IL-1β increased NF-κB and myosin light chain kinase activation in intestinal epithelial cells, thus disrupting the intestinal barrier by opening the tight junctions. Therefore, Y. pseudotuberculosis subverts intestinal barrier function by altering the interplay between immune and epithelial cells during infection. PMID:22565313

  18. Cultural and morphological properties of the vaccine strain Yersinia pestis EV NIIEG bacteria after photodynamic inactivation

    NASA Astrophysics Data System (ADS)

    Ulianova, Onega V.; Lyapina, Anna M.; Khizhnyakova, Mariya A.; Laskavy, Vladislav N.; Feodorova, Valentina A.; Ulyanov, Sergey S.

    2015-03-01

    New method of photoinactivation of plague microbes (bacteria Yersinia pestis) has been suggested. Rate of growth of colonies of Y. pestis EV NIIEG at specific regimes of photo processing have been analyzed. Dependence of growth on exposure time and concentrations of photosensitizer (methylene blue) has been studied. Number of colony forming units of Y. pestis EV NIIEG bacteria as a function of intensity of light and concentration of methylene blue has been scrutinized.

  19. Phenotypic characterization of OmpX, an Ail homologue of Yersinia pestis KIM.

    PubMed

    Kolodziejek, Anna M; Sinclair, Dylan J; Seo, Keun S; Schnider, Darren R; Deobald, Claudia F; Rohde, Harold N; Viall, Austin K; Minnich, Scott S; Hovde, Carolyn J; Minnich, Scott A; Bohach, Gregory A

    2007-09-01

    The goal of this study was to characterize the Yersinia pestis KIM OmpX protein. Yersinia spp. provide a model for studying several virulence processes including attachment to, and internalization by, host cells. For Yersinia enterocolitica and Yersinia pseudotuberculosis, Ail, YadA and Inv, have been implicated in these processes. In Y. pestis, YadA and Inv are inactivated. Genomic analysis of two Y. pestis strains revealed four loci with sequence homology to Ail. One of these genes, designated y1324 in the Y. pestis KIM database, encodes a protein designated OmpX. The mature protein has a predicted molecular mass of 17.47 kDa, shares approximately 70 % sequence identity with Y. enterocolitica Ail, and has an identical homologue, designated Ail, in the Y. pestis CO92 database. The present study compared the Y. pestis KIM6(+) parental strain with a mutant derivative having an engineered disruption of the OmpX structural gene. The parental strain (and a merodiploid control strain) expressed OmpX at 28 and 37 degrees C, and the protein was detectable throughout all phases of growth. OmpX was required for efficient adherence to, and internalization by, cultured HEp-2 cell monolayers and conferred resistance to the bactericidal effect of human serum. Deletion of ompX resulted in a significantly reduced autoaggregation phenotype and loss of pellicle formation in vitro. These results suggest that Y. pestis OmpX shares functional homology with Y. enterocolitica Ail in adherence, internalization into epithelial cells and serum resistance.

  20. Production of Recombinant Injectosome and Outer Membrane Proteins from Yersinia Pestis KIM5

    DTIC Science & Technology

    2009-06-01

    7 2.2 Threat Assessment from WMD ............................................................ 7 2.3 Bacterial Based Biological Weapons (BBBW...Introduction 1.1 Chapter Overview Yersinia pestis, formerly Pasteurella pestis, has long been a blight upon the human species. As the causative agent of...Centers for Disease Control has classified Y. pestis as a Category A Agent (CDC 2009). This bacterial disease is endemic in a large portion of the

  1. Ferrioxamine B analogues: targeting the FoxA uptake system in the pathogenic Yersinia enterocolitica.

    PubMed

    Kornreich-Leshem, Hagit; Ziv, Carmit; Gumienna-Kontecka, Elzbieta; Arad-Yellin, Rina; Chen, Yona; Elhabiri, Mourad; Albrecht-Gary, Anne-Marie; Hadar, Yitzhak; Shanzer, Abraham

    2005-02-02

    A series of ferrioxamine B analogues that target the bacterium Yersinia enterocolitica were prepared. These iron carriers are composed of three hydroxamate-containing monomeric units. Two identical monomers consist of N-hydroxy-3-aminopropionic acid coupled with beta-alanine, and a third unit at the amino terminal is composed of N-hydroxy-3-aminopropionic acid and one of the following amino acids: beta-alanine (1a), phenylalanine (1b), cyclohexylalanine (1c), or glycine (1d). Thermodynamic results for representatives of the analogues have shown a strong destabilization (3-4 orders of magnitude) of the ferric complexes with respect to ferrioxamine B, probably due to shorter spacers and a more strained structure around the metal center. No significant effect of the variations at the N-terminal has been observed on the stability of the ferric complexes. By contrast, using in vivo radioactive uptake experiments, we have found that these modifications have a substantial effect on the mechanism of iron(III) uptake in the pathogenic bacteria Yersinia enterocolitica. Analogues 1a and 1d were utilized by the ferrioxamine B uptake system (FoxA), while 1b and 1c either used different uptake systems or were transported to the microbial cell nonspecifically by diffusion via the cell membrane. Transport via the FoxA system was also confirmed by uptake experiments with the FoxA deficient strain of Yersinia enterocolitica. A fluorescent marker, attached to 1a in a way that did not interfere with its biological activity, provided additional means to monitor the uptake mechanism by fluorescence techniques. Of particular interest is the observation that 1a was utilized by the uptake system of ferrioxamine B in Yersinia enterocolitica (FoxA) but failed to use the ferrioxamine uptake route in Pseudomonas putida. Here, we present a case in which biomimetic siderophore analogues deliberately designed for a particular bacterium can distinguish between related uptake systems of different

  2. Enterobacterial Repetitive Intergenic Consensus Sequence Repeats in Yersiniae: Genomic Organization and Functional Properties

    PubMed Central

    De Gregorio, Eliana; Silvestro, Giustina; Petrillo, Mauro; Carlomagno, Maria Stella; Di Nocera, Pier Paolo

    2005-01-01

    Genome-wide analyses carried out in silico revealed that the DNA repeats called enterobacterial repetitive intergenic consensus sequences (ERICs), which are present in several Enterobacteriaceae, are overrepresented in yersiniae. From the alignment of DNA regions from the wholly sequenced Yersinia enterocolitica 8081 and Yersinia pestis CO92 strains, we could establish that ERICs are miniature mobile elements whose insertion leads to duplication of the dinucleotide TA. ERICs feature long terminal inverted repeats (TIRs) and can fold as RNA into hairpin structures. The proximity to coding regions suggests that most Y. enterocolitica ERICs are cotranscribed with flanking genes. Elements which either overlap or are located next to stop codons are preferentially inserted in the same (or B) orientation. In contrast, ERICs located far apart from open reading frames are inserted in the opposite (or A) orientation. The expression of genes cotranscribed with A- and B-oriented ERICs has been monitored in vivo. In mRNAs spanning B-oriented ERICs, upstream gene transcripts accumulated at lower levels than downstream gene transcripts. This difference was abolished by treating cells with chloramphenicol. We hypothesize that folding of B-oriented elements is impeded by translating ribosomes. Consequently, upstream RNA degradation is triggered by the unmasking of a site for the RNase E located in the right-hand TIR of ERIC. A-oriented ERICs may act in contrast as upstream RNA stabilizers or may have other functions. The hypothesis that ERICs act as regulatory RNA elements is supported by analyses carried out in Yersinia strains which either lack ERIC sequences or carry alternatively oriented ERICs at specific loci. PMID:16291667

  3. The Role of Early-Phase Transmission in the Spread of Yersinia pestis

    PubMed Central

    EISEN, REBECCA J.; DENNIS, DAVID T.; GAGE, KENNETH L.

    2015-01-01

    Early-phase transmission (EPT) of Yersinia pestis by unblocked fleas is a well-documented, replicable phenomenon with poorly defined mechanisms. We review evidence demonstrating EPT and current knowledge on its biological and biomechanical processes. We discuss the importance of EPT in the epizootic spread of Y. pestis and its role in the maintenance of plague bacteria in nature. We further address the role of EPT in the epidemiology of plague. PMID:26336267

  4. Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions.

    PubMed

    Wolters, Manuel; Zobiak, Bernd; Nauth, Theresa; Aepfelbacher, Martin

    2015-10-13

    Many gram-negative bacteria including pathogenic Yersinia spp. employ type III secretion systems to translocate effector proteins into eukaryotic target cells. Inside the host cell the effector proteins manipulate cellular functions to the benefit of the bacteria. To better understand the control of type III secretion during host cell interaction, sensitive and accurate assays to measure translocation are required. We here describe the application of an assay based on the fusion of a Yersinia enterocolitica effector protein fragment (Yersinia outer protein; YopE) with TEM-1 beta-lactamase for quantitative analysis of translocation. The assay relies on cleavage of a cell permeant FRET dye (CCF4/AM) by translocated beta-lactamase fusion. After cleavage of the cephalosporin core of CCF4 by the beta-lactamase, FRET from coumarin to fluorescein is disrupted and excitation of the coumarin moiety leads to blue fluorescence emission. Different applications of this method have been described in the literature highlighting its versatility. The method allows for analysis of translocation in vitro and also in in vivo, e.g., in a mouse model. Detection of the fluorescence signals can be performed using plate readers, FACS analysis or fluorescence microscopy. In the setup described here, in vitro translocation of effector fusions into HeLa cells by different Yersinia mutants is monitored by laser scanning microscopy. Recording intracellular conversion of the FRET reporter by the beta-lactamase effector fusion in real-time provides robust quantitative results. We here show exemplary data, demonstrating increased translocation by a Y. enterocolitica YopE mutant compared to the wild type strain.

  5. A novel high-resolution melting analysis-based method for Yersinia enterocolitica genotyping.

    PubMed

    Souza, Roberto A; Falcão, Juliana P

    2014-11-01

    Pathogenic Yersinia enterocolitica strains are associated with biotypes 1B, 2-5, while environmental strains with biotype 1A. In this work a method for Y. enterocolitica genotyping based on HRMA to determine SNPs was developed and the genetic diversity of 50 strains was determined. The strains were clustered into three groups consistent with the pathogenic profile of each biotype. The results provided a better understanding of the Y. enterocolitica genetic variability.

  6. Complete genome sequence and comparative genome analysis of a new special Yersinia enterocolitica.

    PubMed

    Shi, Guoxiang; Su, Mingming; Liang, Junrong; Duan, Ran; Gu, Wenpeng; Xiao, Yuchun; Zhang, Zhewen; Qiu, Haiyan; Zhang, Zheng; Li, Yi; Zhang, Xiaohe; Ling, Yunchao; Song, Lai; Chen, Meili; Zhao, Yongbing; Wu, Jiayan; Jing, Huaiqi; Xiao, Jingfa; Wang, Xin

    2016-09-01

    Yersinia enterocolitica is the most diverse species among the Yersinia genera and shows more polymorphism, especially for the non-pathogenic strains. Individual non-pathogenic Y. enterocolitica strains are wrongly identified because of atypical phenotypes. In this study, we isolated an unusual Y. enterocolitica strain LC20 from Rattus norvegicus. The strain did not utilize urea and could not be classified as the biotype. API 20E identified Escherichia coli; however, it grew well at 25 °C, but E. coli grew well at 37 °C. We analyzed the genome of LC20 and found the whole chromosome of LC20 was collinear with Y. enterocolitica 8081, and the urease gene did not exist on the genome which is consistent with the result of API 20E. Also, the 16 S and 23 SrRNA gene of LC20 lay on a branch of Y. enterocolitica. Furthermore, the core-based and pan-based phylogenetic trees showed that LC20 was classified into the Y. enterocolitica cluster. Two plasmids (80 and 50 k) from LC20 shared low genetic homology with pYV from the Yersinia genus, one was an ancestral Yersinia plasmid and the other was novel encoding a number of transposases. Some pathogenic and non-pathogenic Y. enterocolitica-specific genes coexisted in LC20. Thus, although it could not be classified into any Y. enterocolitica biotype due to its special biochemical metabolism, we concluded the LC20 was a Y. enterocolitica strain because its genome was similar to other Y. enterocolitica and it might be a strain with many mutations and combinations emerging in the processes of its evolution.

  7. In Vitro Intracellular Trafficking of Virulence Antigen during Infection by Yersinia pestis

    DTIC Science & Technology

    2009-07-17

    movement of Salmonella typhi in infected cells appears to involve a pattern of vesicular trafficking via endosome and lysosomes [77]. This infection...the Yersinia spp . Observations reported using an in vitro model of gastric epithelial cell infection indicate that, like V, H. pylori exhibits a... Salmonella - induced caspase-2 activation in macrophages: a novel mechanism in pathogen- mediated apoptosis. J Exp Med 192: 1035–1046. 59. Johannes L

  8. Yersinia pseudotuberculosis IP32953 survives and replicates in trophozoites and persists in cysts of Acanthamoeba castellanii

    PubMed Central

    Santos-Montañez, Jennifer; Benavides-Montaño, Javier A.; Hinz, Angela K.; Vadyvaloo, Viveka

    2015-01-01

    Yersinia pseudotuberculosis is a foodborne enteric pathogen that causes a mild self-limiting diarrhea in humans. Yersinia pseudotuberculosis is able to persist in soil and water and in association with fresh produce, but the mechanism by which it persists is unknown. It has been shown that Y. pseudotuberculosis co-occurs with protozoans in these environments; therefore, this study investigates if bacterivorous free-living amoeba (FLA) are able to support persistence of Y. pseudotuberculosis. Coculture studies of Y. pseudotuberculosis and the prototype FLA, Acanthamoeba castellanii revealed that bacteria had an enhanced capacity to survive in association with amoeba and in the absence of any cytotoxic effects. Yersinia pseudotuberculosis is able to survive and replicate in trophozoites specifically localized within vacuoles, and persists within cysts over a period of at least a week. These data present the first evidence that Y. pseudotuberculosis is able to resist the bacterivorous nature of FLA and instead exhibits an enhanced ability to replicate and persist in coculture with amoeba. This study sheds light on the potential role of FLA in the ecology of Y. pseudotuberculosis which may have implications for food safety. PMID:26025069

  9. Detection of Yersinia spp. in meat products by enrichment culture, immunomagnetic separation and nested PCR.

    PubMed

    Estrada, Cecilia S M Lucero; Velázquez, Lidia Del Carmen; Favier, Gabriela Isabel; Genaro, María Silvia Di; Escudero, María Esther

    2012-05-01

    The prevalence of Yersinia enterocolitica in meat products was assessed by four methods: cold enrichment in trypticase soy broth (A), enrichment in modified Rappaport broth at 25 °C (B), concentration by immunomagnetic separation (C) and yadA nested PCR (D). Furthermore, the pathogenic potentials of the isolates were established by phenotypic and genotypic tests, and their genomic relationships were determined by pulsed-field gel electrophoresis (PFGE). A total of 238 samples were collected at retail level in the city of San Luis, Argentina, during the period 2007-2008. The highest Yersinia prevalence in meat products was observed by method D (92 positive samples), followed by methods A (13 positive samples) and C (5 positive samples); however, no isolation was obtained by method B. Fourteen Y. enterocolitica and 4 Yersinia intermedia strains were recovered by culture. All Y. enterocolitica 2/O:9 strains gave results related to virulence by phenotypic tests and exhibited the genotype virF(+)myfA(+)ail(+)ystA(+). Two biotype 1A strains showed a genotype virF(-)myfA(-)ail(+)ystA(+)ystB(+). The 14 Y. enterocolitica strains isolated during this work plus one reference strain were separated into 11 genomic types by PFGE. This genomic heterogeneity of the isolates shows the diversity of Y. enterocolitica strains in our region. It is the first time that IMS was used to search Y. enterocolitica strains from naturally contaminated meat products.

  10. Yersinia pseudotuberculosis IP32953 survives and replicates in trophozoites and persists in cysts of Acanthamoeba castellanii.

    PubMed

    Santos-Montañez, Jennifer; Benavides-Montaño, Javier A; Hinz, Angela K; Vadyvaloo, Viveka

    2015-07-01

    Yersinia pseudotuberculosis is a foodborne enteric pathogen that causes a mild self-limiting diarrhea in humans. Yersinia pseudotuberculosis is able to persist in soil and water and in association with fresh produce, but the mechanism by which it persists is unknown. It has been shown that Y. pseudotuberculosis co-occurs with protozoans in these environments; therefore, this study investigates if bacterivorous free-living amoeba (FLA) are able to support persistence of Y. pseudotuberculosis. Coculture studies of Y. pseudotuberculosis and the prototype FLA, Acanthamoeba castellanii revealed that bacteria had an enhanced capacity to survive in association with amoeba and in the absence of any cytotoxic effects. Yersinia pseudotuberculosis is able to survive and replicate in trophozoites specifically localized within vacuoles, and persists within cysts over a period of at least a week. These data present the first evidence that Y. pseudotuberculosis is able to resist the bacterivorous nature of FLA and instead exhibits an enhanced ability to replicate and persist in coculture with amoeba. This study sheds light on the potential role of FLA in the ecology of Y. pseudotuberculosis which may have implications for food safety.

  11. Genome-scale reconstruction of the metabolic network in Yersinia pestis, strain 91001

    SciTech Connect

    Navid, A; Almaas, E

    2009-01-13

    The gram-negative bacterium Yersinia pestis, the aetiological agent of bubonic plague, is one the deadliest pathogens known to man. Despite its historical reputation, plague is a modern disease which annually afflicts thousands of people. Public safety considerations greatly limit clinical experimentation on this organism and thus development of theoretical tools to analyze the capabilities of this pathogen is of utmost importance. Here, we report the first genome-scale metabolic model of Yersinia pestis biovar Mediaevalis based both on its recently annotated genome, and physiological and biochemical data from literature. Our model demonstrates excellent agreement with Y. pestis known metabolic needs and capabilities. Since Y. pestis is a meiotrophic organism, we have developed CryptFind, a systematic approach to identify all candidate cryptic genes responsible for known and theoretical meiotrophic phenomena. In addition to uncovering every known cryptic gene for Y. pestis, our analysis of the rhamnose fermentation pathway suggests that betB is the responsible cryptic gene. Despite all of our medical advances, we still do not have a vaccine for bubonic plague. Recent discoveries of antibiotic resistant strains of Yersinia pestis coupled with the threat of plague being used as a bioterrorism weapon compel us to develop new tools for studying the physiology of this deadly pathogen. Using our theoretical model, we can study the cell's phenotypic behavior under different circumstances and identify metabolic weaknesses which may be harnessed for the development of therapeutics. Additionally, the automatic identification of cryptic genes expands the usage of genomic data for pharmaceutical purposes.

  12. Yersinia Virulence Depends on Mimicry of Host Rho-Family Nucleotide Dissociation Inhibitors

    SciTech Connect

    Prehna,G.; Ivanov, M.; Blisha, J.; Stebbins, C.

    2006-01-01

    Yersinia spp. cause gastroenteritis and the plague, representing historically devastating pathogens that are currently an important biodefense and antibiotic resistance concern. A critical virulence determinant is the Yersinia protein kinase A, or YpkA, a multidomain protein that disrupts the eukaryotic actin cytoskeleton. Here we solve the crystal structure of a YpkA-Rac1 complex and find that YpkA possesses a Rac1 binding domain that mimics host guanidine nucleotide dissociation inhibitors (GDIs) of the Rho GTPases. YpkA inhibits nucleotide exchange in Rac1 and RhoA, and mutations that disrupt the YpkA-GTPase interface abolish this activity in vitro and impair in vivo YpkA-induced cytoskeletal disruption. In cell culture experiments, the kinase and the GDI domains of YpkA act synergistically to promote cytoskeletal disruption, and a Y. pseudotuberculosis mutant lacking YpkA GDI activity shows attenuated virulence in a mouse infection assay. We conclude that virulence in Yersinia depends strongly upon mimicry of host GDI proteins by YpkA.

  13. Yersinia pestis Biofilm in the Flea Vector and Its Role in the Transmission of Plague

    PubMed Central

    Erickson, D. L.

    2013-01-01

    Transmission by fleabite is a relatively recent evolutionary adaptation of Yersinia pestis, the bacterial agent of bubonic plague. To produce a transmissible infection, Y. pestis grows as an attached biofilm in the foregut of the flea vector. Biofilm formation both in the flea foregut and in vitro is dependent on an extracellular matrix (ECM) synthesized by the Yersinia hms gene products. The hms genes are similar to the pga and ica genes of Escherichia coli and Staphylococcus epidermidis, respectively, that act to synthesize a poly-β-1,6-N-acetyl-d-glucosamine ECM required for biofilm formation. As with extracellular polysaccharide production in many other bacteria, synthesis of the Hms-dependent ECM is controlled by intracellular levels of cyclic-di-GMP. Yersinia pseudotuberculosis, the food- and water-borne enteric pathogen from which Y. pestis evolved recently, possesses identical hms genes and can form biofilm in vitro but not in the flea. The genetic changes in Y. pestis that resulted in adapting biofilm-forming capability to the flea gut environment, a critical step in the evolution of vector-borne transmission, have yet to be identified. During a flea bite, Y. pestis is regurgitated into the dermis in a unique biofilm phenotype, and this has implications for the initial interaction with the mammalian innate immune response. PMID:18453279

  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. 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

  16. sugE: A gene involved in tributyltin (TBT) resistance of Aeromonas molluscorum Av27.

    PubMed

    Cruz, Andreia; Micaelo, Nuno; Félix, Vitor; Song, Jun-Young; Kitamura, Shin-Ichi; Suzuki, Satoru; Mendo, Sónia

    2013-01-01

    The mechanism of bacterial resistance to tributyltin (TBT) is still unclear. The results herein presented contribute to clarify that mechanism in the TBT-resistant bacterium Aeromonas molluscorum Av27. We have identified and cloned a new gene that is involved in TBT resistance in this strain. The gene is highly homologous (84%) to the Aeromonas hydrophila-sugE gene belonging to the small multidrug resistance gene family (SMR), which includes genes involved in the transport of lipophilic drugs. In Av27, expression of the Av27-sugE was observed at the early logarithmic growth phase in the presence of a high TBT concentration (500 μM), thus suggesting the contribution of this gene for TBT resistance. E. coli cells transformed with Av27-sugE become resistant to ethidium bromide (EtBr), chloramphenicol (CP) and tetracycline (TE), besides TBT. According to the Moriguchi logP (miLogP) values, EtBr, CP and TE have similar properties and are substrates for the sugE-efflux system. Despite the different miLogP of TBT, E. coli cells transformed with Av27-sugE become resistant to this compound. So it seems that TBT is also a substrate for the SugE protein. The modelling studies performed also support this hypothesis. The data herein presented clearly indicate that sugE is involved in TBT resistance of this bacterium.

  17. Aeromonas punctata derived depolymerase that disrupts the integrity of Klebsiella pneumoniae capsule: optimization of depolymerase production.

    PubMed

    Bansal, Shruti; Soni, Sanjeev Kumar; Harjai, Kusum; Chhibber, Sanjay

    2014-07-01

    Formation of dense, highly hydrated biofilm structures pose a risk for public and environmental health. Extracellular polymeric substances encompassing biofilms offer 1000-fold greater resistance as compared to the planktonic cells. Using enzymes as anti-biofouling agents, will improve penetration of antimicrobials and increase susceptibility of biofilms to components of immune system. The challenge of using enzymes derived from unrelated bacteria for the degradation of capsular matrix of Klebsiella pneumoniae has not been dealt in the past. Thus, statistical optimization was done to enhance depolymerase production by Aeromonas punctata, directed against the exopolysaccharide matrix of Klebsiella pneumoniae B5055, capable of substituting the available phage borne depolymerase enzyme. Optimization via central composite design (CCD) resulted in 16-fold enhancement in depolymerase yield (166.65 µmoles ml(-1)  min(-1) ) over unoptimized medium. Out of the 19 variables, media composition giving maximum expression levels of the enzyme consisted of 1 mg ml(-1) galactose and ammonium chloride, 1.5 mg ml(-1) each of capsular polysaccharide (CPS) and magnesium sulfate. Tryptic peptide analysis of the purified 29 kDa band by Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) showed a high homology with a protein of unknown function from Aeromonas cavaie Ae398. Further improvements in the enzyme can lead to its successful development as prophylactic and/or a therapeutic agent.

  18. Role of MshQ in MSHA pili biosynthesis and biofilm formation of Aeromonas hydrophila.

    PubMed

    Qin, Y X; Yan, Q P; Mao, X X; Chen, Z; Su, Y Q

    2014-10-31

    Biofilm formation of pathogen bacterium is currently one of the most widely studied topics; however, little is known regarding pathogen bacteria biofilms in aquaculture. Aeromonas hydrophila is a representative species of the genus Aeromonas, which has been recognized as a common pathogen, is associated with many diseases in aquatic animals, and causes significant mortality. The objectives of this study are i) to confirm that A. hydrophila can form biofilms on abiotic substrates and construct a biofilm growth curve for this bacterium; ii) to identify the genes that play crucial roles in A. hydrophila biofilm formation. The biofilm growth curve of A. hydrophila was constructed using a crystal violet assay, which showed that biofilm formation for this bacterium is a dynamic process. Next, a mutant library of pathogenic A. hydrophila B11 was constructed using the mini-Tn10 transposon mutagenesis system. A total of 861 mutants were screened, and 5 mutants were stably deficient in biofilm formation. Molecular analysis of the mutant B112 revealed that the open reading frame that encodes the protein MshQ was disrupted. Comparison of biological characteristics including growth, motility, and adhesion between the mutant B112 and the wild-type strain B11 suggested that MshQ is necessary for mannose-sensitive hemagglutinin pilus biosynthesis of A. hydrophila, and that these pili play crucial roles in A.hydrophila adherence to a solid surface during the early stages of biofilm formation.

  19. Antibiotic resistance profiling and phenotyping of Aeromonas species isolated from aquatic sources.

    PubMed

    Odeyemi, Olumide A; Ahmad, Asmat

    2017-01-01

    This study aimed to investigate antibiotics resistance pattern and phenotyping of Aeromonas species isolated from different aquatic sources in Melaka, Malaysia. A total of 53 Aeromonas species were isolated from the following sources: sediment (n = 13), bivalve (n = 10), sea cucumber (n = 16) and sea water (n = 14) and resistance to 12 antibiotics - Tetracycline (30 μg), Kanamycin (30 μg), Oxytetracycline (30 μg), Ampicillin (10 μg), Streptomycin (10 μg), Gentamicin (10 μg), Sulphamethoxazole (25 μg), Nalixidic acid (30 μg), Trimethoprim (1.25 μg), Novobiocin (5 μg), Penicilin (10 μg) and Chloramphenicol (10 μg) was tested. The results obtained from this study reveal multi drug resistance pattern among the isolates. All the isolates were completely resistant to Ampicillin, Novobiocin, Sulphamethoxazole and Trimethoprim, respectively but susceptible to Tetracycline (100%), Kanamycin (5.7%), Gentamicin (5.7%) and Oxytetracycline (24.5%). Antibiotics phenotyping of the bacteria revealed 21 different phenotypes among the isolates.

  20. Evidence for bacterial chemotaxis to cyanobacteria from a radioassay technique. [Lyngbya birgei; Aphanizomenon flos-aquae; Aeromonas hydrophila

    SciTech Connect

    Kangatharalingam, N.; Wang, Lizhu; Priscu, J.C. )

    1991-08-01

    Lyngbya birgei and Aphanizomenon flos-aquae elicited a significant chemotactic attraction of Aeromonas hydrophila compared with controls lacking cyanobacteria. There was a positive exponential relationship between biomass (chlorophyll a) of L. birgei and A. flos-aquae and chemotactic attraction of A. hydrophila. The assay equipment was simple and reliable and could be used to study bacterial chemotaxis in other species in situ.

  1. Chicken-type lysozyme in channel catfish: expression analysis, lysozyme activity, and efficacy as immunostimulant against Aeromonas hydrophila infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To understand whether chicken-type lysozyme (Lys-c) in channel catfish was induced by infection of Aeromonas hydrophila, the transcriptional levels of Lys-c in skin, gut, liver, spleen, posterior kidney, and blood cells in healthy channel catfish was compared to that in channel catfish infected with...

  2. Construction, expression and characterization of eleven putative flagellar apparatus genes of Aeromonas hydrophila AL09-73

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aeromonas hydrophila is ubiquitous in aquatic environments worldwide and is responsible for many human and fish diseases. The genome sequence of A. hydrophila is available in the GenBank database. Our ultimate goal is to develop the whole genome protein arrays of A. hydrophila. In this study, we ...

  3. Draft Genome Sequence of Pseudomonas mosselii Gil3, Isolated from Catfish and Antagonistic against Hypervirulent Aeromonas hydrophila

    PubMed Central

    Xu, De-Hai; Qiu, Junqiang; Rasmussen-Ivey, Cody R.; Liles, Mark R.; Beck, Benjamin H.

    2016-01-01

    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 metabolism pathways and proteins for biosynthesis of antimicrobial compounds. PMID:27856595

  4. 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...

  5. Chicken-type lysozyme in channel catfish: Expression analysis, lysozyme activity and efficacy as immunostimulant against Aeromonas hydrophila infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To understand whether chicken-type lysozyme (Lys-c) in channel catfish was induced by infection of Aeromonas hydrophila, the transcriptional levels of Lys-c in skin, gut, liver, spleen, posterior kidney, and blood cells in healthy channel catfish was compared to that in channel catfish infected with...

  6. Development and efficacy of novobiocin and rifampicin-resistant Aeromonas hydrophila as novel vaccines in channel catfish and Nile tilapia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three attenuated Aeromonas hydrophila vaccines were developed from the virulent 2009 West Alabama isolates through selection for resistance to both novobiocin and rifampicin. When channel catfish (Ictalurus punctatus) were IP injected with 4×105 colony-forming units (CFU) of the mutants, no fish die...

  7. 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...

  8. 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...

  9. Yersinia murine toxin is not required for early-phase transmission of Yersinia pestis by Oropsylla montana (Siphonaptera: Ceratophyllidae) or Xenopsylla cheopis (Siphonaptera: Pulicidae)

    PubMed Central

    Hinnebusch, B. Joseph; Boegler, Karen A.; Graham, Christine B.; MacMillan, Katherine; Montenieri, John A.; Bearden, Scott W.; Gage, Kenneth L.; Eisen, Rebecca J.

    2014-01-01

    Plague, caused by Yersinia pestis, is characterized by quiescent periods punctuated by rapidly spreading epizootics. The classical ‘blocked flea’ paradigm, by which a blockage forms in the flea’s proventriculus on average 1–2 weeks post-infection (p.i.), forces starving fleas to take multiple blood meals, thus increasing opportunities for transmission. Recently, the importance of early-phase transmission (EPT), which occurs prior to blockage formation, has been emphasized during epizootics. Whilst the physiological and molecular mechanisms of blocked flea transmission are well characterized, the pathogen–vector interactions have not been elucidated for EPT. Within the blocked flea model, Yersinia murine toxin (Ymt) has been shown to be important for facilitating colonization of the midgut within the flea. One proposed mechanism of EPT is the regurgitation of infectious material from the flea midgut during feeding. Such a mechanism would require bacteria to colonize and survive for at least brief periods in the midgut, a process that is mediated by Ymt. Two key bridging vectors of Y. pestis to humans, Oropsylla montana (Siphonaptera: Ceratophyllidae) or Xenopsylla cheopis (Siphonaptera: Pulicidae), were used in our study to test this hypothesis. Fleas were infected with a mutant strain of Y. pestis containing a non-functional ymt that was shown previously to be incapable of colonizing the midgut and were then allowed to feed on SKH-1 mice 3 days p.i. Our results show that Ymt was not required for EPT by either flea species. PMID:25187626

  10. Yersinia murine toxin is not required for early-phase transmission of Yersinia pestis by Oropsylla montana (Siphonaptera: Ceratophyllidae) or Xenopsylla cheopis (Siphonaptera: Pulicidae).

    PubMed

    Johnson, Tammi L; Hinnebusch, B Joseph; Boegler, Karen A; Graham, Christine B; MacMillan, Katherine; Montenieri, John A; Bearden, Scott W; Gage, Kenneth L; Eisen, Rebecca J

    2014-11-01

    Plague, caused by Yersinia pestis, is characterized by quiescent periods punctuated by rapidly spreading epizootics. The classical 'blocked flea' paradigm, by which a blockage forms in the flea's proventriculus on average 1-2 weeks post-infection (p.i.), forces starving fleas to take multiple blood meals, thus increasing opportunities for transmission. Recently, the importance of early-phase transmission (EPT), which occurs prior to blockage formation, has been emphasized during epizootics. Whilst the physiological and molecular mechanisms of blocked flea transmission are well characterized, the pathogen-vector interactions have not been elucidated for EPT. Within the blocked flea model, Yersinia murine toxin (Ymt) has been shown to be important for facilitating colonization of the midgut within the flea. One proposed mechanism of EPT is the regurgitation of infectious material from the flea midgut during feeding. Such a mechanism would require bacteria to colonize and survive for at least brief periods in the midgut, a process that is mediated by Ymt. Two key bridging vectors of Y. pestis to humans, Oropsylla montana (Siphonaptera: Ceratophyllidae) or Xenopsylla cheopis (Siphonaptera: Pulicidae), were used in our study to test this hypothesis. Fleas were infected with a mutant strain of Y. pestis containing a non-functional ymt that was shown previously to be incapable of colonizing the midgut and were then allowed to feed on SKH-1 mice 3 days p.i. Our results show that Ymt was not required for EPT by either flea species.

  11. Molecular characterization of antibiotic resistance in Pseudomonas and Aeromonas isolates from catfish of the Mekong Delta, Vietnam.

    PubMed

    Nguyen, Hoang Nam Kha; Van, Thi Thu Hao; Nguyen, Huu Thinh; Smooker, Peter M; Shimeta, Jeff; Coloe, Peter J

    2014-07-16

    A collection of 116 motile Pseudomonas spp. and 92 Aeromonas spp. isolated from 15 Vietnamese intensive catfish farms was analyzed to examine the molecular antibiotic resistance characteristics and the transferability of resistance markers within and between species. High levels of resistance to ampicillin, trimethoprim/sulfamethoxazole, nalidixic acid, chloramphenicol, and nitrofurantoin were observed. The percentage of multiple drug resistance of Pseudomonas spp. and Aeromonas spp. isolates was 96.6% and 61.9%, respectively. The multiple antibiotic resistance (MAR) index mean values of 0.457 and 0.293 of Pseudomonas and Aeromonas isolates, respectively, indicated that these isolates were exposed to high risk sources of contamination where antibiotics were commonly used. Approximately 33% of Pseudomonas spp. and 28% of Aeromonas spp. isolates from catfish contained class 1 integrons, but no class 2 integrons were detected. Several common resistance genes including aadA, dfrA and catB were harbored in class 1 integrons. Large plasmids (>55 kb) were frequently detected in 50% and 71.4% of the plasmids extracted from Pseudomonas and Aeromonas isolates, respectively. Conjugation and transformation experiments demonstrated the successful transfer of all or part of the resistance phenotypes of catfish isolates to the recipient strains, including laboratory strains and strains isolated from this study. These results highlight the likely role of catfish bacteria as a reservoir of antibiotic resistant, Gram-negative bacteria harboring a pool of mobile genetic elements that can readily be transferred intra- and interspecies. To our knowledge, this is the first report on molecular characterization of antibiotic resistance of bacteria isolated from catfish in Vietnam.

  12. Piericidin A1 Blocks Yersinia Ysc Type III Secretion System Needle Assembly

    PubMed Central

    Morgan, Jessica M.; Duncan, Miles C.; Johnson, Kevin S.; Diepold, Andreas; Lam, Hanh; Dupzyk, Allison J.; Martin, Lexi R.; Wong, Weng Ruh; Linington, Roger G.

    2017-01-01

    ABSTRACT The type III secretion system (T3SS) is a bacterial virulence factor expressed by dozens of Gram-negative pathogens but largely absent from commensals. The T3SS is an attractive target for antimicrobial agents that may disarm pathogenic bacteria while leaving commensal populations intact. We previously identified piericidin A1 as an inhibitor of the Ysc T3SS in Yersinia pseudotuberculosis. Piericidins were first discovered as inhibitors of complex I of the electron transport chain in mitochondria and some bacteria. However, we found that piericidin A1 did not alter Yersinia membrane potential or inhibit flagellar motility powered by the proton motive force, indicating that the piericidin mode of action against Yersinia type III secretion is independent of complex I. Instead, piericidin A1 reduced the number of T3SS needle complexes visible by fluorescence microscopy at the bacterial surface, preventing T3SS translocator and effector protein secretion. Furthermore, piericidin A1 decreased the abundance of higher-order YscF needle subunit complexes, suggesting that piericidin A1 blocks YscF needle assembly. While expression of T3SS components in Yersinia are positively regulated by active type III secretion, the block in secretion by piericidin A1 was not accompanied by a decrease in T3SS gene expression, indicating that piericidin A1 may target a T3SS regulatory circuit. However, piericidin A1 still inhibited effector protein secretion in the absence of the T3SS regulator YopK, YopD, or YopN. Surprisingly, while piericidin A1 also inhibited the Y. enterocolitica Ysc T3SS, it did not inhibit the SPI-1 family Ysa T3SS in Y. enterocolitica or the Ysc family T3SS in Pseudomonas aeruginosa. Together, these data indicate that piericidin A1 specifically inhibits Yersinia Ysc T3SS needle assembly. IMPORTANCE The bacterial type III secretion system (T3SS) is widely used by both human and animal pathogens to cause disease yet remains incompletely understood

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

    PubMed

    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

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

    PubMed

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

    2016-02-25

    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.

  16. Purification and characterization of Aeromonas sobria pili, a possible colonization factor.

    PubMed Central

    Hokama, A; Iwanaga, M

    1991-01-01

    Pili of Aeromonas sobria Ae1 were purified and characterized. The molecular mass of the pilin was estimated to be about 23 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The Ae1 pili were electrophoretically and immunologically distinguishable from the W pili of A. hydrophila Ae6, although the two pili were morphologically indistinguishable. The N-terminal amino acid sequences of the two pilins were identical in the first 10 residues. Strain Ae1 and its purified pili adhered to human and rabbit intestines and agglutinated human and rabbit erythrocytes. Hemagglutination was inhibited by D-galactose and D-mannose, but not by L-fucose. Organisms pretreated with the Fab fraction of the antipilus antibody failed to adhere to the intestines. Organisms did not adhere to intestines pretreated with the purified pili. These findings suggest that the pili are a colonization factor of A. sobria Ae1. Images PMID:1680105

  17. Aeromonas hydrophila typing scheme based on patterns of agglutination with erythrocytes and yeast cells.

    PubMed Central

    Adams, D; Atkinson, H M; Woods, W H

    1983-01-01

    An agglutination typing scheme has been developed for strains of Aeromonas hydrophila. Primary agglutination typing is based on testing agar-grown A. hydrophila cells with human, horse, rat, and guinea pig erythrocytes and Saccharomyces cerevisiae cells. Further subdivision of primary groups is based firstly on whether yeast cell agglutination is inhibited by a D-mannose polymer, yeast mannan, and secondly on patterns of inhibition of hemagglutination by yeast mannan and the monomeric sugars L-fucose, D-galactose, and D-mannose. A total of 320 isolates were tested, and these were divisible into 39 distinct types on the basis of this scheme. Application of this typing scheme in the future to isolates of A. hydrophila known to be associated with human infection may enable correlations to be made between particular agglutination types and human pathogenicity. PMID:6841579

  18. Aeromonas dhakensis pneumonia and sepsis in a neonate Risso's dolphin Grampus griseus from the Mediterranean Sea.

    PubMed

    Pérez, Lola; Abarca, M Lourdes; Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Figueras, M José; Domingo, Mariano

    2015-09-17

    A neonate Risso's dolphin Grampus griseus was found stranded alive on a beach in Catalonia, Spain. Rehabilitation attempts were unsuccessful and it died 2 d later, showing pneumonia and sepsis. A pure bacterial culture was obtained from all tissues and blood and identified as Aeromonas hydrophila using the API 20NE. However, sequencing the rpoD gene showed that the strain in fact belongs to A. dhakensis, making this the first report of fatal haemorrhagic-necrotizing pneumonia and sepsis due to this species in a marine mammal. The A. dhakensis strain GMV-704 produced β-haemolysis, possessed several virulence genes and showed sensitivity to several antimicrobials. This study provides a new potential host for A. dhakensis, and its potential virulence in dolphins and its presence in the marine environment may warrant considering this species a potential threat to marine mammals.

  19. Expression of Aeromonas caviae ST pyruvate dehydrogenase complex components mediate tellurite resistance in Escherichia coli

    SciTech Connect

    Castro, Miguel E.; Molina, Roberto C.; Diaz, Waldo A.; Pradenas, Gonzalo A.; Vasquez, Claudio C.

    2009-02-27

    Potassium tellurite (K{sub 2}TeO{sub 3}) is harmful to most organisms and specific mechanisms explaining its toxicity are not well known to date. We previously reported that the lpdA gene product of the tellurite-resistant environmental isolate Aeromonas caviae ST is involved in the reduction of tellurite to elemental tellurium. In this work, we show that expression of A. caviae ST aceE, aceF, and lpdA genes, encoding pyruvate dehydrogenase, dihydrolipoamide transacetylase, and dihydrolipoamide dehydrogenase, respectively, results in tellurite resistance and decreased levels of tellurite-induced superoxide in Escherichia coli. In addition to oxidative damage resulting from tellurite exposure, a metabolic disorder would be simultaneously established in which the pyruvate dehydrogenase complex would represent an intracellular tellurite target. These results allow us to widen our vision regarding the molecular mechanisms involved in bacterial tellurite resistance by correlating tellurite toxicity and key enzymes of aerobic metabolism.

  20. Cloning, Sequencing, and Role in Serum Susceptibility of Porin II from Mesophilic Aeromonas hydrophila

    PubMed Central

    Nogueras, Maria Mercé; Merino, Susana; Aguilar, Alicia; Benedi, Vicente Javier; Tomás, Juan M.

    2000-01-01

    We cloned and sequenced the structural gene for Aeromonas hydrophila porin II from strain AH-3 (serogroup O:34). The genetic position of this gene, like that of ompF in Escherichia coli, is adjacent to aspC and transcribed in the same direction. However, upstream of the porin II gene no similarities with E. coli were found. We obtained defined insertion mutants in porin II gene either in A. hydrophila (O:34) or A. veronii sobria (serogroup O:11) serum-resistant or -sensitive strains. Furthermore, we complemented these mutants with a plasmid harboring only the porin II gene, which allowed us to define the role of porin II as an important surface molecule involved in serum susceptibility and C1q binding in these strains. PMID:10722573