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Sorée M, Lozach S, Kéomurdjian N, Richard D, Hughes A, Delbarre-Ladrat C, Verrez-Bagnis V, Rincé A, Passerini D, Ritchie JM, Heath DH. Virulence phenotypes differ between toxigenic Vibrio parahaemolyticus isolated from western coasts of Europe. Microbiol Res 2024; 285:127744. [PMID: 38735242 DOI: 10.1016/j.micres.2024.127744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 04/19/2024] [Accepted: 04/30/2024] [Indexed: 05/14/2024]
Abstract
Vibrio parahaemolyticus is the leading bacterial cause of gastroenteritis associated with seafood consumption worldwide. Not all members of the species are thought to be pathogenic, thus identification of virulent organisms is essential to protect public health and the seafood industry. Correlations of human disease and known genetic markers (e.g. thermostable direct hemolysin (TDH), TDH-related hemolysin (TRH)) appear complex. Some isolates recovered from patients lack these factors, while their presence has become increasingly noted in isolates recovered from the environment. Here, we used whole-genome sequencing in combination with mammalian and insect models of infection to assess the pathogenic potential of V. parahaemolyticus isolated from European Atlantic shellfish production areas. We found environmental V. parahaemolyticus isolates harboured multiple virulence-associated genes, including TDH and/or TRH. However, carriage of these factors did not necessarily reflect virulence in the mammalian intestine, as an isolate containing TDH and the genes coding for a type 3 secretion system (T3SS) 2α virulence determinant, appeared avirulent. Moreover, environmental V. parahaemolyticus lacking TDH or TRH could be assigned to groups causing low and high levels of mortality in insect larvae, with experiments using defined bacterial mutants showing that a functional T3SS1 contributed to larval death. When taken together, our findings highlight the genetic diversity of V. parahaemolyticus isolates found in the environment, their potential to cause disease and the need for a more systematic evaluation of virulence in diverse V. parahaemolyticus to allow better genetic markers.
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Affiliation(s)
| | - Solen Lozach
- Ifremer, Univ Brest, CNRS, IRD, LEMAR, Plouzané F-29280, France
| | | | | | - Alexandra Hughes
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | | | | | - Alain Rincé
- Biotargen, Université de Caen Normandie, Saint-Contest F-14380, France
| | | | - Jennifer M Ritchie
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom.
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2
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Hsueh BY, Severin GB, Elg CA, Waldron EJ, Kant A, Wessel AJ, Dover JA, Rhoades CR, Ridenhour BJ, Parent KN, Neiditch MB, Ravi J, Top EM, Waters CM. Phage defence by deaminase-mediated depletion of deoxynucleotides in bacteria. Nat Microbiol 2022; 7:1210-1220. [PMID: 35817890 PMCID: PMC9830645 DOI: 10.1038/s41564-022-01162-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 05/24/2022] [Indexed: 02/03/2023]
Abstract
Vibrio cholerae biotype El Tor is perpetuating the longest cholera pandemic in recorded history. The genomic islands VSP-1 and VSP-2 distinguish El Tor from previous pandemic V. cholerae strains. Using a co-occurrence analysis of VSP genes in >200,000 bacterial genomes we built gene networks to infer biological functions encoded in these islands. This revealed that dncV, a component of the cyclic-oligonucleotide-based anti-phage signalling system (CBASS) anti-phage defence system, co-occurs with an uncharacterized gene vc0175 that we rename avcD for anti-viral cytodine deaminase. We show that AvcD is a deoxycytidylate deaminase and that its activity is post-translationally inhibited by a non-coding RNA named AvcI. AvcID and bacterial homologues protect bacterial populations against phage invasion by depleting free deoxycytidine nucleotides during infection, thereby decreasing phage replication. Homologues of avcD exist in all three domains of life, and bacterial AvcID defends against phage infection by combining traits of two eukaryotic innate viral immunity proteins, APOBEC and SAMHD1.
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Affiliation(s)
- Brian Y Hsueh
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | - Geoffrey B Severin
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA
| | - Clinton A Elg
- Department of Biological Sciences, Institute for Interdisciplinary Data Sciences, Bioinformatics and Computational Biology Program, University of Idaho, Moscow, ID, USA
| | - Evan J Waldron
- Department of Microbiology, Biochemistry, and Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ, USA
- Department of Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Abhiruchi Kant
- Department of Microbiology, Biochemistry, and Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Alex J Wessel
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | - John A Dover
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Christopher R Rhoades
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | - Benjamin J Ridenhour
- Department of Mathematics and Statistical Sciences, University of Idaho, Moscow, ID, USA
| | - Kristin N Parent
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Matthew B Neiditch
- Department of Microbiology, Biochemistry, and Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Janani Ravi
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, USA
| | - Eva M Top
- Department of Biological Sciences, Institute for Interdisciplinary Data Sciences, Bioinformatics and Computational Biology Program, University of Idaho, Moscow, ID, USA
| | - Christopher M Waters
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA.
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3
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Meparambu Prabhakaran D, Patel HR, Sivakumar Krishnankutty Chandrika S, Thomas S. Genomic attributes differ between Vibrio parahaemolyticus environmental and clinical isolates including pathotypes. ENVIRONMENTAL MICROBIOLOGY REPORTS 2022; 14:365-375. [PMID: 34461673 DOI: 10.1111/1758-2229.13000] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
Vibrio parahaemolyticus is a marine bacterium and causes opportunistic gastroenteritis in humans. Clinical strains of V. parahaemolyticus contain haemolysin and type III secretion systems (T3SS) that define their pathotype. A growing number of strains isolated recently from the environment have acquired these virulence genes constituting a pool of potential pathogens. This study used comparative genomics to identify genetic factors that delineate environmental and clinical V. parahaemolyticus population and understand the similarities and differences between the T3SS2 phylotypes. The comparative analysis revealed the presence of a cluster of genes belonging to bacterial cellulose synthesis (bcs) in isolates of environmental origin. This cluster, previously unreported in V. parahaemolyticus, exhibit significant similarity to that of Aliivibrio fischeri, and might dictate a potentially new mechanism of its environmental adaptation and persistence. The study also identified many genes predicted in silico to be T3SS effectors that are unique to T3SS2β of tdh- trh+ and tdh+ trh+ pathotype and having no identifiable homologue in tdh+ trh- T3SS2α. Overall, these findings highlight the importance of understanding the genes and strategies V. parahaemolyticus utilize for the myriad interactions with its hosts, either marine invertebrates or humans.
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Affiliation(s)
- Divya Meparambu Prabhakaran
- Cholera and Biofilm Research Lab, Department of Pathogen Biology, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | - Hardip R Patel
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, 2601, Australia
| | | | - Sabu Thomas
- Cholera and Biofilm Research Lab, Department of Pathogen Biology, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
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4
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Beck KL, Haiminen N, Chambliss D, Edlund S, Kunitomi M, Huang BC, Kong N, Ganesan B, Baker R, Markwell P, Kawas B, Davis M, Prill RJ, Krishnareddy H, Seabolt E, Marlowe CH, Pierre S, Quintanar A, Parida L, Dubois G, Kaufman J, Weimer BC. Monitoring the microbiome for food safety and quality using deep shotgun sequencing. NPJ Sci Food 2021; 5:3. [PMID: 33558514 PMCID: PMC7870667 DOI: 10.1038/s41538-020-00083-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 11/24/2020] [Indexed: 01/30/2023] Open
Abstract
In this work, we hypothesized that shifts in the food microbiome can be used as an indicator of unexpected contaminants or environmental changes. To test this hypothesis, we sequenced the total RNA of 31 high protein powder (HPP) samples of poultry meal pet food ingredients. We developed a microbiome analysis pipeline employing a key eukaryotic matrix filtering step that improved microbe detection specificity to >99.96% during in silico validation. The pipeline identified 119 microbial genera per HPP sample on average with 65 genera present in all samples. The most abundant of these were Bacteroides, Clostridium, Lactococcus, Aeromonas, and Citrobacter. We also observed shifts in the microbial community corresponding to ingredient composition differences. When comparing culture-based results for Salmonella with total RNA sequencing, we found that Salmonella growth did not correlate with multiple sequence analyses. We conclude that microbiome sequencing is useful to characterize complex food microbial communities, while additional work is required for predicting specific species' viability from total RNA sequencing.
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Affiliation(s)
- Kristen L. Beck
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Niina Haiminen
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481554.9IBM T.J. Watson Research Center, Yorktown Heights, Ossining, NY USA
| | - David Chambliss
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Stefan Edlund
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Mark Kunitomi
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - B. Carol Huang
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.27860.3b0000 0004 1936 9684University of California Davis, School of Veterinary Medicine, 100 K Pathogen Genome Project, Davis, CA 95616 USA
| | - Nguyet Kong
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.27860.3b0000 0004 1936 9684University of California Davis, School of Veterinary Medicine, 100 K Pathogen Genome Project, Davis, CA 95616 USA
| | - Balasubramanian Ganesan
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,Mars Global Food Safety Center, Beijing, China ,grid.507690.dWisdom Health, A Division of Mars Petcare, Vancouver, WA USA
| | - Robert Baker
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,Mars Global Food Safety Center, Beijing, China
| | - Peter Markwell
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,Mars Global Food Safety Center, Beijing, China
| | - Ban Kawas
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Matthew Davis
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Robert J. Prill
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Harsha Krishnareddy
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Ed Seabolt
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Carl H. Marlowe
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.418312.d0000 0001 2187 1663Bio-Rad Laboratories, Hercules, CA USA
| | - Sophie Pierre
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481801.40000 0004 0623 3323Bio-Rad, Food Science Division, MArnes-La-Coquette, France
| | - André Quintanar
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481801.40000 0004 0623 3323Bio-Rad, Food Science Division, MArnes-La-Coquette, France
| | - Laxmi Parida
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481554.9IBM T.J. Watson Research Center, Yorktown Heights, Ossining, NY USA
| | - Geraud Dubois
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - James Kaufman
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.481551.cIBM Almaden Research Center, San Jose, CA USA
| | - Bart C. Weimer
- Consortium for Sequencing the Food Supply Chain, San Jose, CA USA ,grid.27860.3b0000 0004 1936 9684University of California Davis, School of Veterinary Medicine, 100 K Pathogen Genome Project, Davis, CA 95616 USA
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5
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Miller JJ, Weimer BC, Timme R, Lüdeke CHM, Pettengill JB, Bandoy DJD, Weis AM, Kaufman J, Huang BC, Payne J, Strain E, Jones JL. Phylogenetic and Biogeographic Patterns of Vibrio parahaemolyticus Strains from North America Inferred from Whole-Genome Sequence Data. Appl Environ Microbiol 2021; 87:e01403-20. [PMID: 33187991 PMCID: PMC7848924 DOI: 10.1128/aem.01403-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 11/04/2020] [Indexed: 11/20/2022] Open
Abstract
Vibrio parahaemolyticus is the most common cause of seafood-borne illness reported in the United States. The draft genomes of 132 North American clinical and oyster V. parahaemolyticus isolates were sequenced to investigate their phylogenetic and biogeographic relationships. The majority of oyster isolate sequence types (STs) were from a single harvest location; however, four were identified from multiple locations. There was population structure along the Gulf and Atlantic Coasts of North America, with what seemed to be a hub of genetic variability along the Gulf Coast, with some of the same STs occurring along the Atlantic Coast and one shared between the coastal waters of the Gulf and those of Washington State. Phylogenetic analyses found nine well-supported clades. Two clades were composed of isolates from both clinical and oyster sources. Four were composed of isolates entirely from clinical sources, and three were entirely from oyster sources. Each single-source clade consisted of one ST. Some human isolates lack tdh, trh, and some type III secretion system (T3SS) genes, which are established virulence genes of V. parahaemolyticus Thus, these genes are not essential for pathogenicity. However, isolates in the monophyletic groups from clinical sources were enriched in several categories of genes compared to those from monophyletic groups of oyster isolates. These functional categories include cell signaling, transport, and metabolism. The identification of genes in these functional categories provides a basis for future in-depth pathogenicity investigations of V. parahaemolyticusIMPORTANCEVibrio parahaemolyticus is the most common cause of seafood-borne illness reported in the United States and is frequently associated with shellfish consumption. This study contributes to our knowledge of the biogeography and functional genomics of this species around North America. STs shared between the Gulf Coast and the Atlantic seaboard as well as Pacific waters suggest possible transport via oceanic currents or large shipping vessels. STs frequently isolated from humans but rarely, if ever, isolated from the environment are likely more competitive in the human gut than other STs. This could be due to additional functional capabilities in areas such as cell signaling, transport, and metabolism, which may give these isolates an advantage in novel nutrient-replete environments such as the human gut.
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Affiliation(s)
- John J Miller
- FDA, Biostatistics and Bioinformatics Staff, College Park, Maryland, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA
| | - Bart C Weimer
- University of California-Davis, Institute for Veterinary Medicine, Davis, California, USA
| | - Ruth Timme
- FDA, Division of Microbiology, College Park, Maryland, USA
| | - Catharina H M Lüdeke
- FDA, Division of Seafood Science and Technology, Gulf Coast Seafood Laboratory, Dauphin Island, Alabama, USA
- University of Hamburg, Hamburg School of Food Science, Hamburg, Germany
| | - James B Pettengill
- FDA, Biostatistics and Bioinformatics Staff, College Park, Maryland, USA
| | - DJ Darwin Bandoy
- University of California-Davis, Institute for Veterinary Medicine, Davis, California, USA
| | - Allison M Weis
- University of California-Davis, Institute for Veterinary Medicine, Davis, California, USA
| | | | - B Carol Huang
- University of California-Davis, Institute for Veterinary Medicine, Davis, California, USA
| | - Justin Payne
- FDA, Division of Microbiology, College Park, Maryland, USA
| | - Errol Strain
- FDA, Biostatistics and Bioinformatics Staff, College Park, Maryland, USA
| | - Jessica L Jones
- FDA, Division of Seafood Science and Technology, Gulf Coast Seafood Laboratory, Dauphin Island, Alabama, USA
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6
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Food authentication from shotgun sequencing reads with an application on high protein powders. NPJ Sci Food 2019; 3:24. [PMID: 31754632 PMCID: PMC6863864 DOI: 10.1038/s41538-019-0056-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 08/23/2019] [Indexed: 01/19/2023] Open
Abstract
Here we propose that using shotgun sequencing to examine food leads to accurate authentication of ingredients and detection of contaminants. To demonstrate this, we developed a bioinformatic pipeline, FASER (Food Authentication from SEquencing Reads), designed to resolve the relative composition of mixtures of eukaryotic species using RNA or DNA sequencing. Our comprehensive database includes >6000 plants and animals that may be present in food. FASER accurately identified eukaryotic species with 0.4% median absolute difference between observed and expected proportions on sequence data from various sources including sausage meat, plants, and fish. FASER was applied to 31 high protein powder raw factory ingredient total RNA samples. The samples mostly contained the expected source ingredient, chicken, while three samples unexpectedly contained pork and beef. Our results demonstrate that DNA/RNA sequencing of food ingredients, combined with a robust analysis, can be used to find contaminants and authenticate food ingredients in a single assay.
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7
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Edlind T, Richards GP. Development and Evaluation of Polymorphic Locus Sequence Typing for Epidemiological Tracking of Vibrio parahaemolyticus. Foodborne Pathog Dis 2019; 16:752-760. [PMID: 31144991 DOI: 10.1089/fpd.2019.2649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Vibrio parahaemolyticus is a common inhabitant of coastal estuaries, and can accumulate to high levels in the shellfish that populate those waters. Human gastrointestinal infection occasionally follows ingestion of raw oysters, and it can lead to extended closures of implicated oyster beds with serious economic consequences. To track down the source of human infection, and to monitor strain variation in the environment, a user-friendly and affordable typing method that provides sufficient resolution for epidemiological analysis is needed. Polymorphic locus sequence typing (PLST) is based on conventional PCR and dideoxynucleotide sequencing of the one or two most phylogenetically informative genomic loci. Bioinformatic analyses of GenBank databases identified the V. parahaemolyticus polymorphic tandem repeat-containing loci VpMT1 and VpMT2 on chromosomes 1 and 2, respectively, as promising PLST targets, yielding diversity indexes of 0.99. Phylogenetic analysis identified multiple clusters representing strains known or likely to be epidemiologically related. Correlations with serotype and multilocus sequence type were strong but resolution was higher; for example, North American ST36 strains yielded 16 VpMT1 alleles. In the laboratory, VpMT1 and VpMT2 were robust, resolving 16 of 17 strains following PCR and sequencing directly from heat-killed colonies. Finally, 4 of 13 retail oyster enrichments yielded VpMT sequences that were unique but closely related to previously characterized clinical or environmental V. parahaemolyticus isolates.
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Affiliation(s)
- Tom Edlind
- MicrobiType LLC, Plymouth Meeting, Pennsylvania
| | - Gary P Richards
- U.S. Department of Agriculture, Agricultural Research Service, Dover, Delaware
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8
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Chung HY, Lee B, Na EJ, Lee KH, Ryu S, Yoon H, Lee JH, Kim HB, Kim H, Jeong HG, Kim BS, Choi SH. Potential Survival and Pathogenesis of a Novel Strain, Vibrio parahaemolyticus FORC_022, Isolated From a Soy Sauce Marinated Crab by Genome and Transcriptome Analyses. Front Microbiol 2018; 9:1504. [PMID: 30034383 PMCID: PMC6043650 DOI: 10.3389/fmicb.2018.01504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 06/18/2018] [Indexed: 11/13/2022] Open
Abstract
Vibrio parahaemolyticus can cause gastrointestinal illness through consumption of seafood. Despite frequent food-borne outbreaks of V. parahaemolyticus, only 19 strains have subjected to complete whole-genome analysis. In this study, a novel strain of V. parahaemolyticus, designated FORC_022 (Food-borne pathogen Omics Research Center_022), was isolated from soy sauce marinated crabs, and its genome and transcriptome were analyzed to elucidate the pathogenic mechanisms. FORC_022 did not include major virulence factors of thermostable direct hemolysin (tdh) and TDH-related hemolysin (trh). However, FORC_022 showed high cytotoxicity and had several V. parahaemolyticus islands (VPaIs) and other virulence factors, such as various secretion systems (types I, II, III, IV, and VI), in comparative genome analysis with CDC_K4557 (the most similar strain) and RIMD2210633 (genome island marker strain). FORC_022 harbored additional virulence genes, including accessory cholera enterotoxin, zona occludens toxin, and tight adhesion (tad) locus, compared with CDC_K4557. In addition, O3 serotype specific gene and the marker gene of pandemic O3:K6 serotype (toxRS) were detected in FORC_022. The expressions levels of genes involved in adherence and carbohydrate transporter were high, whereas those of genes involved in motility, arginine biosynthesis, and proline metabolism were low after exposure to crabs. Moreover, the virulence factors of the type III secretion system, tad locus, and thermolabile hemolysin were overexpressed. Therefore, the risk of foodborne-illness may be high following consumption of FORC_022 contaminated crab. These results provided molecular information regarding the survival and pathogenesis of V. parahaemolyticus FORC_022 strain in contaminated crab and may have applications in food safety.
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Affiliation(s)
- Han Y Chung
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, South Korea.,Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea
| | - Byungho Lee
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, South Korea.,Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea
| | - Eun J Na
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, South Korea.,Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea
| | - Kyu-Ho Lee
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea.,Department of Life Science, Sogang University, Seoul, South Korea
| | - Sangryeol Ryu
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, South Korea.,Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea
| | - Hyunjin Yoon
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea.,Department of Applied Chemistry & Biological Engineering, Ajou University, Suwon, South Korea
| | - Ju-Hoon Lee
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea.,Department of Food Science and Biotechnology, Kyung Hee University, Yongin, South Korea
| | - Hyeun B Kim
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea.,Department of Animal Resources Science, Dankook University, Cheonan, South Korea
| | - Heebal Kim
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea.,Department of Animal Science and Biotechnology, Seoul National University, Seoul, South Korea
| | - Hee G Jeong
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea.,Department of Food Science and Technology, Chungnam National University, Daejeon, South Korea
| | - Bong-Soo Kim
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea.,Department of Life Science, Multidisciplinary Genome Institute, Hallym University, Chuncheon, South Korea
| | - Sang H Choi
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, South Korea.,Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, South Korea
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9
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Using genome-scale metabolic models to compare serovars of the foodborne pathogen Listeria monocytogenes. PLoS One 2018; 13:e0198584. [PMID: 29879172 PMCID: PMC6012718 DOI: 10.1371/journal.pone.0198584] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 05/22/2018] [Indexed: 01/06/2023] Open
Abstract
Listeria monocytogenes is a microorganism of great concern for the food industry and the cause of human foodborne disease. Therefore, novel methods of control are needed, and systems biology is one such approach to identify them. Using a combination of computational techniques and laboratory methods, genome-scale metabolic models (GEMs) can be created, validated, and used to simulate growth environments and discern metabolic capabilities of microbes of interest, including L. monocytogenes. The objective of the work presented here was to generate GEMs for six different strains of L. monocytogenes, and to both qualitatively and quantitatively validate these GEMs with experimental data to examine the diversity of metabolic capabilities of numerous strains from the three different serovar groups most associated with foodborne outbreaks and human disease. Following qualitative validation, 57 of the 95 carbon sources tested experimentally were present in the GEMs, and; therefore, these were the compounds from which comparisons could be drawn. Of these 57 compounds, agreement between in silico predictions and in vitro results for carbon source utilization ranged from 80.7% to 91.2% between strains. Nutrient utilization agreement between in silico predictions and in vitro results were also conducted for numerous nitrogen, phosphorous, and sulfur sources. Additionally, quantitative validation showed that the L. monocytogenes GEMs were able to generate in silico predictions for growth rate and growth yield that were strongly and significantly (p < 0.0013 and p < 0.0015, respectively) correlated with experimental results. These findings are significant because they show that these GEMs for L. monocytogenes are comparable to published GEMs of other organisms for agreement between in silico predictions and in vitro results. Therefore, as with the other GEMs, namely those for Escherichia coli, Staphylococcus aureus, Vibrio vulnificus, and Salmonella spp., they can be used to determine new methods of growth control and disease treatment.
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10
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Petronella N, Ronholm J. The mechanisms that regulate Vibrio parahaemolyticus virulence gene expression differ between pathotypes. Microb Genom 2018; 4. [PMID: 29813014 PMCID: PMC6096935 DOI: 10.1099/mgen.0.000182] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Most Vibrio parahaemolyticus isolates found in marine environments are non-pathogenic; however, certain lineages have acquired genomic pathogenicity islands (PAIs) that enable these isolates to cause human illness. The V. parahaemolyticus PAI contains one or both of two toxins: thermostable direct haemolysin (TDH) or TDH-related haemolysin (TRH) and type III secretion system 2 (T3SS2). Recently, a few V. parahaemolyticus isolates that do not have this PAI were obtained from clinical samples, and there has been interest in determining whether these isolates possess novel virulence factors. In this investigation, we have selected four V. parahaemolyticus isolates: a canonical pathogenic strain containing TDH, TRH and T3SS2; two strains from clinical cases which do not contain a PAI; and an environmental isolate which also does not contain a PAI. For each isolate, we analyzed differential gene expression after crude bile exposure. Several enteric bacterial pathogens are known to use bile as a signal to enhance virulence gene expression. We have shown that in the tdh-positive trh-positive pathotype gene virulence gene expression was not up-regulated in response to crude bile, strongly indicating that the current dogma of virulence gene regulation in V. parahaemolyticus needs to be revisited and separately investigated for each pathotype. In addition, we have created a list of genes of interest that were up-regulated in the non-canonical pathotypes which may contribute to virulence in these isolates.
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Affiliation(s)
- Nicholas Petronella
- 1Biostatistics and Modelling Division, Bureau of Food Surveillance and Science Integration, Food Directorate, Health Canada, Ottawa, ON, Canada
| | - Jennifer Ronholm
- 2Department of Animal Science, McGill University, Ste-Anne-de-Bellevue, QC, Canada.,3Department of Food Science and Agricultural Chemistry, McGill University, Ste-Anne-de-Bellevue, QC, Canada
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11
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Lawton SJ, Weis AM, Byrne BA, Fritz H, Taff CC, Townsend AK, Weimer BC, Mete A, Wheeler S, Boyce WM. Comparative analysis of Campylobacter isolates from wild birds and chickens using MALDI-TOF MS, biochemical testing, and DNA sequencing. J Vet Diagn Invest 2018; 30:354-361. [PMID: 29528812 PMCID: PMC6505823 DOI: 10.1177/1040638718762562] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was compared to conventional biochemical testing methods and nucleic acid analyses (16S rDNA sequencing, hippurate hydrolysis gene testing, whole genome sequencing [WGS]) for species identification of Campylobacter isolates obtained from chickens ( Gallus gallus domesticus, n = 8), American crows ( Corvus brachyrhynchos, n = 17), a mallard duck ( Anas platyrhynchos, n = 1), and a western scrub-jay ( Aphelocoma californica, n = 1). The test results for all 27 isolates were in 100% agreement between MALDI-TOF MS, the combined results of 16S rDNA sequencing, and the hippurate hydrolysis gene PCR ( p = 0.0027, kappa = 1). Likewise, the identifications derived from WGS from a subset of 14 isolates were in 100% agreement with the MALDI-TOF MS identification. In contrast, biochemical testing misclassified 5 isolates of C. jejuni as C. coli, and 16S rDNA sequencing alone was not able to differentiate between C. coli and C. jejuni for 11 sequences ( p = 0.1573, kappa = 0.0857) when compared to MALDI-TOF MS and WGS. No agreement was observed between MALDI-TOF MS dendrograms and the phylogenetic relationships revealed by rDNA sequencing or WGS. Our results confirm that MALDI-TOF MS is a fast and reliable method for identifying Campylobacter isolates to the species level from wild birds and chickens, but not for elucidating phylogenetic relationships among Campylobacter isolates.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Walter M. Boyce
- Walter M. Boyce, Department
of Pathology, Microbiology and Immunology, University of California, Davis, 1
Shields Avenue, Davis, CA 95616.
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12
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Obaidat MM, Salman AEB, Roess AA. Virulence and Antibiotic Resistance of Vibrio parahaemolyticus Isolates from Seafood from Three Developing Countries and of Worldwide Environmental, Seafood, and Clinical Isolates from 2000 to 2017. J Food Prot 2017; 80:2060-2067. [PMID: 29154715 DOI: 10.4315/0362-028x.jfp-17-156] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Vibrio parahaemolyticus is a leading cause of seafood-associated illness. This study investigated the prevalence, virulence, and antibiotic resistance of V. parahaemolyticus in three low- and middle-income countries. Freshly caught fish samples (n = 330) imported to Jordan from Yemen, India, and Egypt were tested. The overall prevalence of V. parahaemolyticus was 15% (95% confidence interval: 11 to 19%). Three isolates (6%) were positive for the thermostable direct hemolysin-related (trh) gene, and all isolates was negative for the thermostable direct hemolysin (tdh) gene. All isolates were resistant to colistin sulfate, neomycin, and kanamycin, and 51 and 43% of isolates were resistant to tetracycline and ampicillin, respectively. Only 4% of the isolates were resistant to cefotaxime and chloramphenicol, and no isolates were resistant to sulfamethoxazole-trimethoprim, streptomycin, gentamicin, ciprofloxacin, and nalidixic acid. All isolates were resistant to two classes of antibiotics, and 86% were multidrug resistant (resistant to at least one drug in three or more classes of antibiotics). A literature review of clinical, seafood, and environmental V. parahaemolyticus isolates worldwide revealed high rates of gentamicin and ampicillin resistance, emerging resistance to third-generation cephalosporins, and limited resistance to sulfamethoxazole-trimethoprim, ciprofloxacin, nalidixic acid, and chloramphenicol. Thus, last-resort antibiotics could be ineffective for treating V. parahaemolyticus infections. Several global reports also documented illness outbreaks in humans caused by trh- and tdh-negative V. parahaemolyticus strains. More research is needed to determine whether the presence of these genes is sufficient to classify the strains as virulent.
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Affiliation(s)
- Mohammad M Obaidat
- 1 Department of Veterinary Pathology and Public Health, Faculty of Veterinary Medicine, Jordan University of Science and Technology, Irbid, Jordan 22110; and
| | - Alaa E Bani Salman
- 1 Department of Veterinary Pathology and Public Health, Faculty of Veterinary Medicine, Jordan University of Science and Technology, Irbid, Jordan 22110; and
| | - Amira A Roess
- 2 Department of Global Health, George Washington University, Washington, D.C. 20052, USA
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13
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Variation of genomic islands and flanking fragments in Vibrio parahaemolyticus isolates from environmental and clinical sources in Taiwan. Int J Food Microbiol 2017; 259:68-76. [PMID: 28841447 DOI: 10.1016/j.ijfoodmicro.2017.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 08/08/2017] [Accepted: 08/08/2017] [Indexed: 01/28/2023]
Abstract
Vibrio parahaemolyticus is a halophilic foodborne pathogenic bacterium that causes gastroenteritis; it has become an issue of global concern since the emergence and spread of pandemic O3:K6 strains. This study evaluated the role of Vibrio pathogenicity island (VPaI)-associated fragments in the genetic variation and grouping of this pathogen. Distribution of some VPaI fragments and flanking fragments (VPaI-1, VPaI-4, VPaI-5, VPaI-6 and VPaI-7) was determined in a total of 53 V. parahaemolyticus isolates from environmental and clinical sources in Taiwan, and supported by the sequences of seven fragments of VPaI-4 and its flanking fragment VP2145. As determined from the distribution of these VPaI-associated fragments, the clinical pandemic isolates were closely related in a single cluster; the clinical nonpandemic isolates were grouped into several clusters, while the environmental isolates were comparatively highly diversified. The profiles of virulence-associated genes of environmental pathogenic isolates varied, and were closer to those of clinical nonpandemic isolates than those of pandemic isolates. Isolates with atypical profiles of the VPaI-associated fragments and virulence-associated genes were identified. Sequences of VP2145 exhibited a close phylogenetic relationship among these local isolates, which were distinct from most V. parahaemolyticus strains from other geographic regions. This investigation demonstrated the application of VPaI-associated fragments in studying the genetic variation and clustering of V. parahaemolyticus isolates from different sources.
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14
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Draft Genome Sequences of Salmonella enterica Serovar Typhimurium LT2 with Deleted Chitinases That Are Emerging Virulence Factors. GENOME ANNOUNCEMENTS 2017; 5:5/31/e00659-17. [PMID: 28774970 PMCID: PMC5543632 DOI: 10.1128/genomea.00659-17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Chitinases are glycosyl hydrolases that catalyze the hydrolysis of the β-1,4 linkages in complex carbohydrates and those that contain GlcNAc. These enzymes are considered emerging virulence factors during infection because the host glycan changes. This is the release of four single chitinase deletion mutants in Salmonella enterica serovar Typhimurium LT2.
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15
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Abstract
The 100K Pathogen Genome Project is producing draft and closed genome sequences from diverse pathogens. This project expanded globally to include a snapshot of global bacterial genome diversity. The genomes form a sequence database that has a variety of uses from systematics to public health.
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16
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Draft Genome Sequences of Salmonella Lysozyme Gene Knockout Mutants. GENOME ANNOUNCEMENTS 2017; 5:5/23/e00519-17. [PMID: 28596411 PMCID: PMC5465630 DOI: 10.1128/genomea.00519-17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lysozyme enzymes hydrolyze the β-1,4-glycosidic bond in oligosaccharides. These enzymes are part of a broad group of glucoside hydrolases that are poorly characterized; however, they are important for growth and are being recognized as emerging virulence factors. This is the release of four lysozyme-encoding-gene-deletion mutants in Salmonella enterica serovar Typhimurium LT2.
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17
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Amylases and Their Importance during Glycan Degradation: Genome Sequence Release of Salmonella Amylase Knockout Strains. GENOME ANNOUNCEMENTS 2017; 5:5/20/e00355-17. [PMID: 28522713 PMCID: PMC5477324 DOI: 10.1128/genomea.00355-17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Amylases catalyze the cleavage of α-d-1,4 and α-d-1,6-glycosidic bonds in starch and related carbohydrates. Amylases are widely distributed in nature and are important in carbohydrate metabolism. This is the release of four single and two double deletions in Salmonella enterica serovar Typhimurium LT2 that are important for glycan degradation during infection.
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18
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Implication of Sialidases in Salmonella Infection: Genome Release of Sialidase Knockout Strains from Salmonella enterica Serovar Typhimurium LT2. GENOME ANNOUNCEMENTS 2017; 5:5/19/e00341-17. [PMID: 28495784 PMCID: PMC5427219 DOI: 10.1128/genomea.00341-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sialidases, which are widely distributed in nature, cleave the α-ketosidic bond of terminal sialic acid residue. These emerging virulence factors degrade the host glycan. We report here the release of seven sialidase and one sialic acid transporter deletion in Salmonella enterica serovar Typhimurium strain LT2, which are important in cellular invasion during infection.
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19
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Defining a Core Genome Multilocus Sequence Typing Scheme for the Global Epidemiology of Vibrio parahaemolyticus. J Clin Microbiol 2017; 55:1682-1697. [PMID: 28330888 PMCID: PMC5442524 DOI: 10.1128/jcm.00227-17] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 03/11/2017] [Indexed: 01/27/2023] Open
Abstract
Vibrio parahaemolyticus is an important human foodborne pathogen whose transmission is associated with the consumption of contaminated seafood, with a growing number of infections reported over recent years worldwide. A multilocus sequence typing (MLST) database for V. parahaemolyticus was created in 2008, and a large number of clones have been identified, causing severe outbreaks worldwide (sequence type 3 [ST3]), recurrent outbreaks in certain regions (e.g., ST36), or spreading to other regions where they are nonendemic (e.g., ST88 or ST189). The current MLST scheme uses sequences of 7 genes to generate an ST, which results in a powerful tool for inferring the population structure of this pathogen, although with limited resolution, especially compared to pulsed-field gel electrophoresis (PFGE). The application of whole-genome sequencing (WGS) has become routine for trace back investigations, with core genome MLST (cgMLST) analysis as one of the most straightforward ways to explore complex genomic data in an epidemiological context. Therefore, there is a need to generate a new, portable, standardized, and more advanced system that provides higher resolution and discriminatory power among V. parahaemolyticus strains using WGS data. We sequenced 92 V. parahaemolyticus genomes and used the genome of strain RIMD 2210633 as a reference (with a total of 4,832 genes) to determine which genes were suitable for establishing a V. parahaemolyticus cgMLST scheme. This analysis resulted in the identification of 2,254 suitable core genes for use in the cgMLST scheme. To evaluate the performance of this scheme, we performed a cgMLST analysis of 92 newly sequenced genomes, plus an additional 142 strains with genomes available at NCBI. cgMLST analysis was able to distinguish related and unrelated strains, including those with the same ST, clearly showing its enhanced resolution over conventional MLST analysis. It also distinguished outbreak-related from non-outbreak-related strains within the same ST. The sequences obtained from this work were deposited and are available in the public database (http://pubmlst.org/vparahaemolyticus). The application of this cgMLST scheme to the characterization of V. parahaemolyticus strains provided by different laboratories from around the world will reveal the global picture of the epidemiology, spread, and evolution of this pathogen and will become a powerful tool for outbreak investigations, allowing for the unambiguous comparison of strains with global coverage.
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20
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Draper JL, Hansen LM, Bernick DL, Abedrabbo S, Underwood JG, Kong N, Huang BC, Weis AM, Weimer BC, van Vliet AHM, Pourmand N, Solnick JV, Karplus K, Ottemann KM. Fallacy of the Unique Genome: Sequence Diversity within Single Helicobacter pylori Strains. mBio 2017; 8:e02321-16. [PMID: 28223462 PMCID: PMC5358919 DOI: 10.1128/mbio.02321-16] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 01/30/2017] [Indexed: 12/30/2022] Open
Abstract
Many bacterial genomes are highly variable but nonetheless are typically published as a single assembled genome. Experiments tracking bacterial genome evolution have not looked at the variation present at a given point in time. Here, we analyzed the mouse-passaged Helicobacter pylori strain SS1 and its parent PMSS1 to assess intra- and intergenomic variability. Using high sequence coverage depth and experimental validation, we detected extensive genome plasticity within these H. pylori isolates, including movement of the transposable element IS607, large and small inversions, multiple single nucleotide polymorphisms, and variation in cagA copy number. The cagA gene was found as 1 to 4 tandem copies located off the cag island in both SS1 and PMSS1; this copy number variation correlated with protein expression. To gain insight into the changes that occurred during mouse adaptation, we also compared SS1 and PMSS1 and observed 46 differences that were distinct from the within-genome variation. The most substantial was an insertion in cagY, which encodes a protein required for a type IV secretion system function. We detected modifications in genes coding for two proteins known to affect mouse colonization, the HpaA neuraminyllactose-binding protein and the FutB α-1,3 lipopolysaccharide (LPS) fucosyltransferase, as well as genes predicted to modulate diverse properties. In sum, our work suggests that data from consensus genome assemblies from single colonies may be misleading by failing to represent the variability present. Furthermore, we show that high-depth genomic sequencing data of a population can be analyzed to gain insight into the normal variation within bacterial strains.IMPORTANCE Although it is well known that many bacterial genomes are highly variable, it is nonetheless traditional to refer to, analyze, and publish "the genome" of a bacterial strain. Variability is usually reduced ("only sequence from a single colony"), ignored ("just publish the consensus"), or placed in the "too-hard" basket ("analysis of raw read data is more robust"). Now that whole-genome sequences are regularly used to assess virulence and track outbreaks, a better understanding of the baseline genomic variation present within single strains is needed. Here, we describe the variability seen in typical working stocks and colonies of pathogen Helicobacter pylori model strains SS1 and PMSS1 as revealed by use of high-coverage mate pair next-generation sequencing (NGS) and confirmed by traditional laboratory techniques. This work demonstrates that reliance on a consensus assembly as "the genome" of a bacterial strain may be misleading.
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Affiliation(s)
- Jenny L Draper
- Institute of Environmental Science and Research, Porirua, New Zealand
- Department of Biomolecular Engineering, UC Santa Cruz, Santa Cruz, California, USA
- Department of Microbiology & Environmental Toxicology, UC Santa Cruz, Santa Cruz, California, USA
| | - Lori M Hansen
- Departments of Medicine and Microbiology & Immunology, Center for Comparative Medicine, UC Davis, California, USA
| | - David L Bernick
- Department of Biomolecular Engineering, UC Santa Cruz, Santa Cruz, California, USA
| | - Samar Abedrabbo
- Department of Microbiology & Environmental Toxicology, UC Santa Cruz, Santa Cruz, California, USA
| | | | - Nguyet Kong
- Department of Population Health and Reproduction, 100K Pathogen Genome Project, UC Davis, Davis, California, USA
| | - Bihua C Huang
- Department of Population Health and Reproduction, 100K Pathogen Genome Project, UC Davis, Davis, California, USA
| | - Allison M Weis
- Department of Population Health and Reproduction, 100K Pathogen Genome Project, UC Davis, Davis, California, USA
| | - Bart C Weimer
- Department of Population Health and Reproduction, 100K Pathogen Genome Project, UC Davis, Davis, California, USA
| | - Arnoud H M van Vliet
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Nader Pourmand
- Department of Biomolecular Engineering, UC Santa Cruz, Santa Cruz, California, USA
| | - Jay V Solnick
- Departments of Medicine and Microbiology & Immunology, Center for Comparative Medicine, UC Davis, California, USA
| | - Kevin Karplus
- Department of Biomolecular Engineering, UC Santa Cruz, Santa Cruz, California, USA
| | - Karen M Ottemann
- Department of Microbiology & Environmental Toxicology, UC Santa Cruz, Santa Cruz, California, USA
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21
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Draft Genome Sequences of Campylobacter jejuni Strains That Cause Abortion in Livestock. GENOME ANNOUNCEMENTS 2016; 4:4/6/e01324-16. [PMID: 27908990 PMCID: PMC5137404 DOI: 10.1128/genomea.01324-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Campylobacter jejuni is an intestinal bacterium that can cause abortion in livestock. This publication announces the public release of 15 Campylobacter jejuni genome sequences from isolates linked to abortion in livestock. These isolates are part of the 100K Pathogen Genome Project and are from clinical cases at the University of California (UC) Davis.
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22
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Genomic Comparison of Campylobacter spp. and Their Potential for Zoonotic Transmission between Birds, Primates, and Livestock. Appl Environ Microbiol 2016; 82:7165-7175. [PMID: 27736787 DOI: 10.1128/aem.01746-16] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 09/30/2016] [Indexed: 12/30/2022] Open
Abstract
Campylobacter is the leading cause of human gastroenteritis worldwide. Wild birds, including American crows, are abundant in urban, suburban, and agricultural settings and are likely zoonotic vectors of Campylobacter Their proximity to humans and livestock increases the potential spreading of Campylobacter via crows between the environment, livestock, and humans. However, no studies have definitively demonstrated that crows are a vector for pathogenic Campylobacter We used genomics to evaluate the zoonotic and pathogenic potential of Campylobacter from crows to other animals with 184 isolates obtained from crows, chickens, cows, sheep, goats, humans, and nonhuman primates. Whole-genome analysis uncovered two distinct clades of Campylobacter jejuni genotypes; the first contained genotypes found only in crows, while a second genotype contained "generalist" genomes that were isolated from multiple host species, including isolates implicated in human disease, primate gastroenteritis, and livestock abortion. Two major β-lactamase genes were observed frequently in these genomes (oxa-184, 55%, and oxa-61, 29%), where oxa-184 was associated only with crows and oxa-61 was associated with generalists. Mutations in gyrA, indicative of fluoroquinolone resistance, were observed in 14% of the isolates. Tetracycline resistance (tetO) was present in 22% of the isolates, yet it occurred in 91% of the abortion isolates. Virulence genes were distributed throughout the genomes; however, cdtC alleles recapitulated the crow-only and generalist clades. A specific cdtC allele was associated with abortion in livestock and was concomitant with tetO These findings indicate that crows harboring a generalist C. jejuni genotype may act as a vector for the zoonotic transmission of Campylobacter IMPORTANCE: This study examined the link between public health and the genomic variation of Campylobacter in relation to disease in humans, primates, and livestock. Use of large-scale whole-genome sequencing enabled population-level assessment to find new genes that are linked to livestock disease. With 184 Campylobacter genomes, we assessed virulence traits, antibiotic resistance susceptibility, and the potential for zoonotic transfer to observe that there is a "generalist" genotype that may move between host species.
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23
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Ahn S, Chung HY, Lim S, Kim K, Kim S, Na EJ, Caetano-Anolles K, Lee JH, Ryu S, Choi SH, Kim H. Complete genome of Vibrio parahaemolyticus FORC014 isolated from the toothfish. Gut Pathog 2016; 8:59. [PMID: 27891183 PMCID: PMC5114773 DOI: 10.1186/s13099-016-0134-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 10/19/2016] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Foodborne illness can occur due to various pathogenic bacteria such as Staphylococcus aureus, Escherichia coli and Vibrio parahaemolyticus, and can cause severe gastroenteritis symptoms. In this study, we completed the genome sequence of a foodborne pathogen V. parahaemolyticus FORC_014, which was isolated from suspected contaminated toothfish from South Korea. Additionally, we extended our knowledge of genomic characteristics of the FORC_014 strain through comparative analysis using the complete sequences of other V. parahaemolyticus strains whose complete genomes have previously been reported. RESULTS The complete genome sequence of V. parahaemolyticus FORC_014 was generated using the PacBio RS platform with single molecule, real-time (SMRT) sequencing. The FORC_014 strain consists of two circular chromosomes (3,241,330 bp for chromosome 1 and 1,997,247 bp for chromosome 2), one plasmid (51,383 bp), and one putative phage sequence (96,896 bp). The genome contains a total of 4274 putative protein coding sequences, 126 tRNA genes and 34 rRNA genes. Furthermore, we found 33 type III secretion system 1 (T3SS1) related proteins and 15 type III secretion system 2 (T3SS2) related proteins on chromosome 1. This is the first reported result of Type III secretion system 2 located on chromosome 1 of V. parahaemolyticus without thermostable direct hemolysin (tdh) and thermostable direct hemolysin-related hemolysin (trh). CONCLUSIONS Through investigation of the complete genome sequence of V. parahaemolyticus FORC_014, which differs from previously reported strains, we revealed two type III secretion systems (T3SS1, T3SS2) located on chromosome 1 which do not include tdh and trh genes. We also identified several virulence factors carried by our strain, including iron uptake system, hemolysin and secretion system. This result suggests that the FORC_014 strain may be one pathogen responsible for foodborne illness outbreak. Our results provide significant genomic clues which will assist in future understanding of virulence at the genomic level and help distinguish between clinical and non-clinical isolates.
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Affiliation(s)
- Sojin Ahn
- Interdisciplinary Program in Bioinformatics, Seoul National University, Kwan-ak St. 599, Kwan-ak Gu, Seoul, 151-741 Republic of Korea.,Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea
| | - Han Young Chung
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea.,Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Sooyeon Lim
- Microbiomics and Immunity Research Center, Korean Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahackro, Yuseong-gu, Daejeon, Republic of Korea
| | - Kwondo Kim
- Interdisciplinary Program in Bioinformatics, Seoul National University, Kwan-ak St. 599, Kwan-ak Gu, Seoul, 151-741 Republic of Korea.,C&K genomics, Seoul National University Research Park, Seoul, 151-919 Republic of Korea
| | - Suyeon Kim
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea.,Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Eun Jung Na
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea.,Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Kelsey Caetano-Anolles
- Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Republic of Korea
| | - Ju-Hoon Lee
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea.,Department of Food Science and Biotechnology, Kyung Hee University, 1732 Deokyoungdae-ro, Yongin, 17104 Republic of Korea
| | - Sangryeol Ryu
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea.,Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Sang Ho Choi
- Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea.,Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Heebal Kim
- Interdisciplinary Program in Bioinformatics, Seoul National University, Kwan-ak St. 599, Kwan-ak Gu, Seoul, 151-741 Republic of Korea.,Food-borne Pathogen Omics Research Center (FORC), Seoul National University, Seoul, Republic of Korea.,C&K genomics, Seoul National University Research Park, Seoul, 151-919 Republic of Korea.,Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Republic of Korea
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24
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Influence of Host Ecology and Behavior on Campylobacter jejuni Prevalence and Environmental Contamination Risk in a Synanthropic Wild Bird Species. Appl Environ Microbiol 2016; 82:4811-20. [PMID: 27260356 DOI: 10.1128/aem.01456-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 05/15/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Campylobacter jejuni is a foodborne pathogen that often leads to human infections through the consumption of contaminated poultry. Wild birds may play a role in the transmission of C. jejuni by acting as reservoir hosts. Despite ample evidence that wild birds harbor C. jejuni, few studies have addressed the role of host ecology in transmission to domestic animals or humans. We tested the hypothesis that host social behavior and habitat play a major role in driving transmission risk. C. jejuni infection and host ecology were studied simultaneously in wild American crows (Corvus brachyrhynchos) in Davis, CA, over 3 years. We found that 178 of 337 samples tested were culture positive (53%), with infection varying by season and host age. Among adult crows, infection rates were highest during the winter, when migrants return and crows form large communal roosts. Nestlings had the highest risk of infection, and whole-genome sequencing supports the observation of direct transmission between nestlings. We deployed global positioning system (GPS) receivers to quantify habitat use by crows; space use was nonrandom, with crows preferentially occupying some habitats while avoiding others. This behavior drastically amplified the risk of environmental contamination from feces in specific locations. This study demonstrates that social behavior contributes to infection within species and that habitat use leads to a heterogeneous risk of cross-species transmission. IMPORTANCE Campylobacter jejuni is the most common cause of gastroenteritis in industrialized countries. Despite efforts to reduce the colonization of poultry flocks and eventual infection of humans, the incidence of human C. jejuni infection has remained high. Because wild birds can harbor strains of C. jejuni that eventually infect humans, there has long been speculation that wild birds might act as an important reservoir in the C. jejuni infection cycle. We simultaneously studied infection prevalence, social behavior, and movement ecology in wild American crows (Corvus brachyrhynchos). We found that social behavior contributed to patterns of infection and that movement behavior resulted in some areas having a high risk of transmission while others had a low risk. The incorporation of ecological data into studies of C. jejuni in wild birds has the potential to resolve when and how wild birds contribute to domestic animal and human C. jejuni infection, leading to better control of initial poultry contamination.
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Salmonella Degrades the Host Glycocalyx Leading to Altered Infection and Glycan Remodeling. Sci Rep 2016; 6:29525. [PMID: 27389966 PMCID: PMC4937416 DOI: 10.1038/srep29525] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 06/17/2016] [Indexed: 12/13/2022] Open
Abstract
Complex glycans cover the gut epithelial surface to protect the cell from the environment. Invasive pathogens must breach the glycan layer before initiating infection. While glycan degradation is crucial for infection, this process is inadequately understood. Salmonella contains 47 glycosyl hydrolases (GHs) that may degrade the glycan. We hypothesized that keystone genes from the entire GH complement of Salmonella are required to degrade glycans to change infection. This study determined that GHs recognize the terminal monosaccharides (N-acetylneuraminic acid (Neu5Ac), galactose, mannose, and fucose) and significantly (p < 0.05) alter infection. During infection, Salmonella used its two GHs sialidase nanH and amylase malS for internalization by targeting different glycan structures. The host glycans were altered during Salmonella association via the induction of N-glycan biosynthesis pathways leading to modification of host glycans by increasing fucosylation and mannose content, while decreasing sialylation. Gene expression analysis indicated that the host cell responded by regulating more than 50 genes resulting in remodeled glycans in response to Salmonella treatment. This study established the glycan structures on colonic epithelial cells, determined that Salmonella required two keystone GHs for internalization, and left remodeled host glycans as a result of infection. These data indicate that microbial GHs are undiscovered virulence factors.
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A Nonautochthonous U.S. Strain of Vibrio parahaemolyticus Isolated from Chesapeake Bay Oysters Caused the Outbreak in Maryland in 2010. Appl Environ Microbiol 2016; 82:3208-3216. [PMID: 26994080 DOI: 10.1128/aem.00096-16] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 03/15/2016] [Indexed: 12/25/2022] Open
Abstract
UNLABELLED In the summer of 2010, Vibrio parahaemolyticus caused an outbreak in Maryland linked to the consumption of oysters. Strains isolated from both stool and oyster samples were indistinguishable by pulsed-field gel electrophoresis (PFGE). However, the oysters contained other potentially pathogenic V. parahaemolyticus strains exhibiting different PFGE patterns. In order to assess the identity, genetic makeup, relatedness, and potential pathogenicity of the V. parahaemolyticus strains, we sequenced 11 such strains (2 clinical strains and 9 oyster strains). We analyzed these genomes by in silico multilocus sequence typing (MLST) and determined their phylogeny using a whole-genome MLST (wgMLST) analysis. Our in silico MLST analysis identified six different sequence types (STs) (ST8, ST676, ST810, ST811, ST34, and ST768), with both of the clinical and four of the oyster strains being identified as belonging to ST8. Using wgMLST, we showed that the ST8 strains from clinical and oyster samples were nearly indistinguishable and belonged to the same outbreak, confirming that local oysters were the source of the infections. The remaining oyster strains were genetically diverse, differing in >3,000 loci from the Maryland ST8 strains. eBURST analysis comparing these strains with strains of other STs available at the V. parahaemolyticus MLST website showed that the Maryland ST8 strains belonged to a clonal complex endemic to Asia. This indicates that the ST8 isolates from clinical and oyster sources were likely not endemic to Maryland. Finally, this study demonstrates the utility of whole-genome sequencing (WGS) and associated analyses for source-tracking investigations. IMPORTANCE Vibrio parahaemolyticus is an important foodborne pathogen and the leading cause of bacterial infections in the United States associated with the consumption of seafood. In the summer of 2010, Vibrio parahaemolyticus caused an outbreak in Maryland linked to oyster consumption. Strains isolated from stool and oyster samples were indistinguishable by pulsed-field gel electrophoresis (PFGE). The oysters also contained other potentially pathogenic V. parahaemolyticus strains with different PFGE patterns. Since their identity, genetic makeup, relatedness, and potential pathogenicity were unknown, their genomes were determined by using next-generation sequencing. Whole-genome sequencing (WGS) analysis by whole-genome multilocus sequence typing (wgMLST) allowed (i) identification of clinical and oyster strains with matching PFGE profiles as belonging to ST8, (ii) determination of oyster strain diversity, and (iii) identification of the clinical strains as belonging to a clonal complex (CC) described only in Asia. Finally, WGS and associated analyses demonstrated their utility for trace-back investigations.
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Kim S, Chung HY, Lee DH, Lim JG, Kim SK, Ku HJ, Kim YT, Kim H, Ryu S, Lee JH, Choi SH. Complete genome sequence of Vibrio parahaemolyticus strain FORC_008, a foodborne pathogen from a flounder fish in South Korea. Pathog Dis 2016; 74:ftw044. [PMID: 27170457 DOI: 10.1093/femspd/ftw044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2016] [Indexed: 02/04/2023] Open
Abstract
Vibrio parahaemolyticus is a Gram-negative, motile, nonspore-forming pathogen that causes foodborne illness associated with the consumption of contaminated seafoods. Although many cases of foodborne outbreaks caused by V. parahaemolyticus have been reported, the genomes of only five strains have been completely sequenced and analyzed using bioinformatics. In order to characterize overall virulence factors and pathogenesis of V. parahaemolyticus associated with foodborne outbreak in South Korea, a new strain FORC_008 was isolated from flounder fish and its genome was completely sequenced. The genomic analysis revealed that the genome of FORC_008 consists of two circular DNA chromosomes of 3266 132 bp (chromosome I) and 1772 036 bp (chromosome II) with a GC content of 45.36% and 45.53%, respectively. The entire genome contains 4494 predicted open reading frames, 129 tRNAs and 31 rRNA genes. While the strain FORC_008 does not have genes encoding thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH), its genome encodes many other virulence factors including hemolysins, pathogenesis-associated secretion systems and iron acquisition systems, suggesting that it may be a potential pathogen. This report provides an extended understanding on V. parahaemolyticus in genomic level and would be helpful for rapid detection, epidemiological investigation and prevention of foodborne outbreak in South Korea.
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Affiliation(s)
- Suyeon Kim
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Republic of Korea
| | - Han Young Chung
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Republic of Korea
| | - Dong-Hoon Lee
- Department of Food Science and Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Jong Gyu Lim
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Republic of Korea
| | - Se Keun Kim
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Republic of Korea
| | - Hye-Jin Ku
- Department of Food Science and Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Yongin 17104, Republic of Korea
| | - You-Tae Kim
- Department of Food Science and Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Heebal Kim
- Department of Agricultural Biotechnology, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Sangryeol Ryu
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Republic of Korea
| | - Ju-Hoon Lee
- Department of Food Science and Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Sang Ho Choi
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Seoul National University, Seoul 08826, Republic of Korea
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Trh (tdh−/trh+) gene analysis of clinical, environmental and food isolates of Vibrio parahaemolyticus as a tool for investigating pathogenicity. Int J Food Microbiol 2016; 225:43-53. [DOI: 10.1016/j.ijfoodmicro.2016.02.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 02/24/2016] [Accepted: 02/25/2016] [Indexed: 01/28/2023]
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Genomic Features of Environmental and Clinical Vibrio parahaemolyticus Isolates Lacking Recognized Virulence Factors Are Dissimilar. Appl Environ Microbiol 2015; 82:1102-1113. [PMID: 26637607 DOI: 10.1128/aem.03465-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 11/25/2015] [Indexed: 11/20/2022] Open
Abstract
Vibrio parahaemolyticus is a bacterial pathogen that can cause illness after the consumption or handling of contaminated seafood. The primary virulence factors associated with V. parahaemolyticus illness are thermostable direct hemolysin (TDH) and Tdh-related hemolysin (TRH). However, clinical strains lacking tdh and trh have recently been isolated, and these clinical isolates are poorly understood. To help understand the emergence of clinical tdh- and trh-negative isolates, a genomic approach was used to comprehensively compare 4 clinical tdh- and trh-negative isolates with 16 environmental tdh- and trh-negative isolates and 34 clinical isolates positive for tdh or trh, or both, with the objective of identifying genomic features that are unique to clinical tdh- and trh-negative isolates. The prevalence of pathogenicity islands (PAIs) common to clinical isolates was thoroughly examined in each of the clinical tdh- and trh-negative isolates. The tdh PAI was not present in any clinical or environmental tdh- and trh-negative isolates. The trh PAI was not present in any environmental isolates; however, in clinical tdh- and trh-negative isolate 10-4238, the majority of the trh PAI including a partial trh1 gene was present, which resulted in reclassification of this isolate as a tdh-negative and trh-positive isolate. In the other clinical tdh- and trh-negative isolates, neither the trh gene nor the trh PAI was present. We identified 862 genes in clinical tdh- and trh-negative isolates but not in environmental tdh- and trh-negative isolates. Many of these genes are highly homologous to genes found in common enteric bacteria and included genes encoding a number of chemotaxis proteins and a novel putative type VI secretion system (T6SS) effector and immunity protein (T6SS1). The availability of genome sequences from clinical V. parahaemolyticus tdh- and trh-negative isolates and the comparative analysis may help provide an understanding of how this pathotype is able to survive in vivo during clinical illness.
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