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Prithvisagar KS, Gollapalli P, D’Souza C, Rai P, Karunasagar I, Karunasagar I, Ballamoole KK. Genome analysis of clinical genotype Vibrio vulnificus isolated from seafood in Mangaluru Coast, India provides insights into its pathogenicity. Vet Q 2023; 43:1-17. [PMID: 37478018 PMCID: PMC10438861 DOI: 10.1080/01652176.2023.2240389] [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: 11/29/2022] [Revised: 07/17/2023] [Accepted: 07/19/2023] [Indexed: 07/23/2023] Open
Abstract
Vibrio vulnificus an opportunistic human pathogen native to marine/estuarine environment, is one of the leading causes of death due to seafood consumption and exposure of wounds to seawater worldwide. The present study involves the whole genome sequence analysis of an environmental strain of V. vulnificus (clinical genotype) isolated from seafood along the Mangaluru coast of India. The sequenced genome data was subjected to in-silico analysis of phylogeny, virulence genes, antimicrobial resistance determinants, and secretary proteins using suitable bioinformatics tools. The sequenced isolate had an overall genome length of 4.8 Mb and GC content of 46% with 4400 coding DNA sequences. The sequenced strain belongs to a new sequence type (Multilocus sequence typing) and was also found to branch with a phylogenetic lineage that groups the most infectious strains of V. vulnificus. The seafood isolate had complete genes involved in conferring serum resistance yet showed limited serum resistance. The study identified several genes against the antibiotics that are commonly used in their treatment, highlighting the need for alternative treatments. Also, the secretory protein analysis revealed genes associated with major pathways like ABC transporters, two-component systems, quorum sensing, biofilm formation, cationic antimicrobial peptide (CAMP) resistance, and others that play a critical role in the pathogenesis of the V. vulnificus. To the best of our knowledge, this is the first report of a detailed analysis of the genomic information of a V. vulnificus isolated from the Indian subcontinent and provides evidence that raises public health concerns about the safety of seafood.
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Affiliation(s)
- Kattapuni Suresh Prithvisagar
- Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Mangaluru, India
| | - Pavan Gollapalli
- Center for Bioinformatics and Biostatistics, Nitte (Deemed to be University), Mangaluru, India
| | - Caroline D’Souza
- Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Mangaluru, India
| | - Praveen Rai
- Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Mangaluru, India
| | - Iddya Karunasagar
- Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Mangaluru, India
| | - Indrani Karunasagar
- Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Mangaluru, India
| | - Krishna Kumar Ballamoole
- Department of Infectious Diseases and Microbial Genomics, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Mangaluru, India
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Bonny SQ, Hossain MAM, Uddin SMK, Pulingam T, Sagadevan S, Johan MR. Current trends in polymerase chain reaction based detection of three major human pathogenic vibrios. Crit Rev Food Sci Nutr 2020; 62:1317-1335. [DOI: 10.1080/10408398.2020.1841728] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Sharmin Quazi Bonny
- Nanotechnology and Catalysis Research Centre, Institute of Advanced Studies, University of Malaya, Kuala Lumpur, Malaysia
| | - M. A. Motalib Hossain
- Nanotechnology and Catalysis Research Centre, Institute of Advanced Studies, University of Malaya, Kuala Lumpur, Malaysia
| | - Syed Muhammad Kamal Uddin
- Nanotechnology and Catalysis Research Centre, Institute of Advanced Studies, University of Malaya, Kuala Lumpur, Malaysia
| | - Thiruchelvi Pulingam
- Nanotechnology and Catalysis Research Centre, Institute of Advanced Studies, University of Malaya, Kuala Lumpur, Malaysia
| | - Suresh Sagadevan
- Nanotechnology and Catalysis Research Centre, Institute of Advanced Studies, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohd Rafie Johan
- Nanotechnology and Catalysis Research Centre, Institute of Advanced Studies, University of Malaya, Kuala Lumpur, Malaysia
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D’Souza C, Prithvisagar KS, Deekshit VK, Karunasagar I, Karunasagar I, Kumar BK. Exploring the Pathogenic Potential of Vibrio vulnificus Isolated from Seafood Harvested along the Mangaluru Coast, India. Microorganisms 2020; 8:microorganisms8070999. [PMID: 32635463 PMCID: PMC7409051 DOI: 10.3390/microorganisms8070999] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/10/2020] [Accepted: 05/21/2020] [Indexed: 12/19/2022] Open
Abstract
It has been observed that not all strains of Vibrio vulnificus are virulent. Determining the virulence of strains that are frequently present in seafood is of significance for ensuring seafood safety. This study is an attempt to predict the virulence of seafood-borne V. vulnificus isolated along the Mangaluru Coast, India. The isolates tested possessed a vcgC gene sequence with high similarity to that in the clinical strain. Transcriptional analysis of core virulence genes in seafood isolate E4010 showed the phenomenon of contact-mediated expression of rtxA1 which correlated well with the actin disintegration and cytotoxicity. These results suggest that the seafood isolates tested in this study possess a functional RtxA1 which could help in initiating the infection. However, other putative virulence genes such as vvpE encoding an extracellular protease, vvhA encoding hemolysin, flp encoding tad pilin and ompU encoding fibronectin-binding protein were also constitutively expressed. Virulence-associated attributes such as cytotoxicity and adherence matched the response of the clinical strain (p > 0.05). On the other hand, the environmental strains showed higher serum sensitivity compared with the clinical strain. These findings show that the part of virulence attributes required for the disease process might be intact in these isolates.
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Affiliation(s)
- Caroline D’Souza
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangalore 575018, India; (C.D.); (K.S.P.); (V.K.D.); (I.K.)
| | - Kattapuni Suresh Prithvisagar
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangalore 575018, India; (C.D.); (K.S.P.); (V.K.D.); (I.K.)
| | - Vijay Kumar Deekshit
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangalore 575018, India; (C.D.); (K.S.P.); (V.K.D.); (I.K.)
| | - Indrani Karunasagar
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangalore 575018, India; (C.D.); (K.S.P.); (V.K.D.); (I.K.)
| | - Iddya Karunasagar
- Nitte (Deemed to be University), University Enclave, Medical Sciences Complex, Deralakatte, Mangaluru 575018, India;
| | - Ballamoole Krishna Kumar
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangalore 575018, India; (C.D.); (K.S.P.); (V.K.D.); (I.K.)
- Correspondence: ; Tel.: +91-824-220-4292 (ext. 201)
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4
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D'Souza C, Kumar BK, Rai P, Deekshit VK, Karunasagar I. Application of gyrB targeted SYBR green based qPCR assay for the specific and rapid detection of Vibrio vulnificus in seafood. J Microbiol Methods 2019; 166:105747. [PMID: 31639359 DOI: 10.1016/j.mimet.2019.105747] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 12/17/2022]
Abstract
A SYBR green based qPCR assay targeting a unique region of gyrB was developed for the detection of Vibrio vulnificus. The specificity of the assay was studied using V. vulnificus and other bacterial strains belonging to Vibrio and non-Vibrio species. The assay unambiguously distinguished V.vulnificus with a sensitivity of 101 CFU/mL in pure culture while 102CFU/g was detected in clam meat homogenate with an efficiency of ≥98%.The utility of the qPCR assay was validated with naturally incurred seafood samples, where 24 out of 59(40.67%) seafood samples tested positive for V. vulnificus after 6-8 h enrichment in APW-P broth. In contrast, conventional PCR could detect only 11 samples (18.64%). Our results showed that qPCR assay developed in this study could be used as a rapid method for screening seafood samples for the presence of V. vulnificus, as the assay can be completed within 9-12 h including the enrichment of seafood in APW-P broth. The gyrB targeted qPCR developed in this study can provide excellent results on the presence and load of V. vulnificus in naturally contaminated samples quickly and efficiently; thus it could find application as a routine test in the seafood industry for the analysis V. vulnificus.
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Affiliation(s)
- Caroline D'Souza
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangaluru 575018, Karnataka, India
| | - Ballamoole Krishna Kumar
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangaluru 575018, Karnataka, India.
| | - Praveen Rai
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangaluru 575018, Karnataka, India
| | - Vijay Kumar Deekshit
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangaluru 575018, Karnataka, India
| | - Indrani Karunasagar
- Division of Infectious Diseases, Nitte University Centre for Science Education and Research, Nitte (Deemed to be University), Deralakatte, Mangaluru 575018, Karnataka, India
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Karunasagar I, Maiti B, Kumar BK. Molecular Methods to Study Vibrio parahaemolyticus and Vibrio vulnificus From Atypical Environments. J Microbiol Methods 2018. [DOI: 10.1016/bs.mim.2018.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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6
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The Fish Pathogen
Vibrio vulnificus
Biotype 2: Epidemiology, Phylogeny, and Virulence Factors Involved in Warm-Water Vibriosis. Microbiol Spectr 2015; 3. [DOI: 10.1128/microbiolspec.ve-0005-2014] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
ABSTRACT
Vibrio vulnificus
biotype 2 is the etiological agent of warm-water vibriosis, a disease that affects eels and other teleosts, especially in fish farms. Biotype 2 is polyphyletic and probably emerged from aquatic bacteria by acquisition of a transferable virulence plasmid that encodes resistance to innate immunity of eels and other teleosts. Interestingly, biotype 2 comprises a zoonotic clonal complex designated as serovar E that has extended worldwide. One of the most interesting virulence factors produced by serovar E is RtxA1
3
, a multifunctional protein that acts as a lethal factor for fish, an invasion factor for mice, and a survival factor outside the host. Two practically identical copies of
rtxA1
3
are present in all biotype 2 strains regardless of the serovar, one in the virulence plasmid and the other in chromosome II. The plasmid also contains other genes involved in survival and growth in eel blood:
vep07
, a gene for an outer membrane (OM) lipoprotein involved in resistance to eel serum and
vep20
, a gene for an OM receptor specific for eel-transferrin and, probably, other related fish transferrins. All the three genes are highly conserved within biotype 2, which suggests that they are under a strong selective pressure. Interestingly, the three genes are related with transferable plasmids, which emphasizes the role of horizontal gene transfer in the evolution of
V. vulnificus
in nutrient-enriched aquatic environments, such as fish farms.
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Mechri B, Medhioub A, Medhioub MN, Aouni M. Diversity of Vibrionaceae associated with Ruditapes decussatus hatchery in Tunisia. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0296-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Surasilp T, Longyant S, Rukpratanporn S, Sridulyakul P, Sithigorngul P, Chaivisuthangkura P. Rapid and sensitive detection of Vibrio vulnificus by loop-mediated isothermal amplification combined with lateral flow dipstick targeted to rpoS gene. Mol Cell Probes 2011; 25:158-63. [PMID: 21513793 DOI: 10.1016/j.mcp.2011.04.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2011] [Revised: 03/30/2011] [Accepted: 04/05/2011] [Indexed: 10/18/2022]
Abstract
A novel loop-mediated isothermal amplification (LAMP) combined with amplicon detection by chromatographic lateral flow dipstick (LFD) assay was developed and evaluated for the detection of Vibrio vulnificus. Biotinylated LAMP amplicons were produced by a set of six designed primers that recognized the V. vulnificus RNA polymerase subunit sigma factor S (rpoS) gene followed by hybridization with an FITC-labeled probe and LFD detection. The optimized time and temperature conditions for the LAMP assay were 90 min at 65 °C. The LAMP-LFD method accurately identified 14 isolates of V. vulnificus but did not detect 25 non-vulnificus Vibrio isolates and 37 non-Vibrio isolates. The sensitivity of LAMP-LFD for V. vulnificus detection in pure culture was 1.5 × 10(3) CFU ml(-1) or equivalent to 2.8 CFU per reaction. In the case of spiked oyster samples without enrichment, the detection limit for V. vulnificus was 1.2 × 10(4) CFU g(-1) or equivalent to 11 CFU per reaction. The results show that this method appears to be accurate, precise and valuable tool for identification of V. vulnificus and can be used efficiently for detection of V. vulnificus in contaminated food sample.
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Affiliation(s)
- Thanai Surasilp
- Department of Biology, Srinakharinwirot University, Sukhumvit, Bangkok, Thailand
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Genetic characterization of Vibrio vulnificus strains from tilapia aquaculture in Bangladesh. Appl Environ Microbiol 2010; 76:4890-5. [PMID: 20495047 DOI: 10.1128/aem.00636-10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Outbreaks of Vibrio vulnificus wound infections in Israel were previously attributed to tilapia aquaculture. In this study, V. vulnificus was frequently isolated from coastal but not freshwater aquaculture in Bangladesh. Phylogenetic analyses showed that strains from Bangladesh differed remarkably from isolates commonly recovered elsewhere from fish or oysters and were more closely related to strains of clinical origin.
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10
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Shekar M, Acharya S, Karunasagar I, Karunasagar I. Variable repeat regions in the genome of Vibrio vulnificus and polymorphism in one of the loci in strains isolated from oysters. Int J Food Microbiol 2008; 123:240-5. [PMID: 18374439 DOI: 10.1016/j.ijfoodmicro.2008.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 02/12/2008] [Accepted: 02/12/2008] [Indexed: 10/22/2022]
Abstract
Vibrio vulnificus an estuarine bacterium is associated with severe wound infections and fatal septicemia related to consumption of raw shellfish. In this study we screened the two whole genome sequences available for V. vulnificus in GenBank for the presence of variable number of tandem repeat (VNTR) regions. Five potential VNTR loci with unit repeat size ranging from 6-7 nucleotides were identified for V. vulnificus genome. One of the loci designated Vv1 was selected to detect the repeat number present in V. vulnificus strains isolated from oyster samples in India. Twenty six of the thirty samples tested were found to be highly polymorphic for the Vv1 locus. Copy numbers for the hexanucleotide motif ranged from 4-55, giving rise to a total of 17 polymorphic groups. Our analysis, shows that different genotypic variants exist in the environment and the VNTR loci studied can be used as a marker for strain discrimination and in epidemiological study of this organism.
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Affiliation(s)
- Malathi Shekar
- Department of Fishery Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries , Mangalore 575 002, India
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11
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Cohen ALV, Oliver JD, DePaola A, Feil EJ, Boyd EF. Emergence of a virulent clade of Vibrio vulnificus and correlation with the presence of a 33-kilobase genomic island. Appl Environ Microbiol 2007; 73:5553-65. [PMID: 17616611 PMCID: PMC2042058 DOI: 10.1128/aem.00635-07] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vibrio vulnificus is a ubiquitous inhabitant of the marine coastal environment, and an important pathogen of humans. We characterized a globally distributed sample of environmental isolates from a range of habitats and hosts and compared these with isolates recovered from cases of human infection. Multilocus sequence typing data using six housekeeping genes divided 63 of the 67 isolates into the two main lineages previously noted for this species, and this division was also confirmed using the 16S rRNA and open reading frame VV0401 markers. Lineage I was comprised exclusively of biotype 1 isolates, whereas lineage II contained biotype 1 and all biotype 2 isolates. Four isolates did not cluster within either lineage: two biotype 3 and two biotype 1 isolates. The proportion of isolates recovered from a clinical setting was noted to be higher in lineage I than in lineage II. Lineage I isolates were also associated with a 33-kb genomic island (region XII), one of three regions identified by genome comparisons as unique to the species. Region XII contained an arylsulfatase gene cluster, a sulfate reduction system, two chondroitinase genes, and an oligopeptide ABC transport system, all of which are absent from the majority of lineage II isolates. Arylsulfatases and the sulfate reduction system, along with performing a scavenging role, have been hypothesized to play a role in pathogenic processes in other bacteria. Our data suggest that lineage I may have a higher pathogenic potential and that region XII, along with other regions, may give isolates a selective advantage either in the human host or in the aquatic environment or both.
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Affiliation(s)
- Ana Luisa V Cohen
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
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12
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Tracz DM, Backhouse PG, Olson AB, McCrea JK, Walsh JA, Ng LK, Gilmour MW. Rapid detection of Vibrio species using liquid microsphere arrays and real-time PCR targeting the ftsZ locus. J Med Microbiol 2007; 56:56-65. [PMID: 17172518 DOI: 10.1099/jmm.0.46759-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The development of rapid and sensitive molecular techniques for the detection of Vibrio species would be useful for the surveillance of sporadic infections and management of major outbreaks. Comparative sequence analysis of the ftsZ gene in the predominant Vibrio species that cause human disease revealed distinct alleles for each examined species, including Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus. Light Upon eXtension (LUX) real-time PCR assays were developed to target these species-specific polymorphisms, and were successful in rapidly differentiating the major pathogenic Vibrio species. Luminex liquid microsphere array technology was used to develop a comprehensive assay capable of simultaneously detecting V. cholerae, V. parahaemolyticus and V. vulnificus. These assays permitted the identification of a presumptive V. parahaemolyticus isolate as Vibrio alginolyticus, which was verified using additional molecular characterization.
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Affiliation(s)
- Dobryan M Tracz
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
| | - Paul G Backhouse
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
| | - Adam B Olson
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
| | - Joanne K McCrea
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
| | - Julie A Walsh
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
| | - Lai-King Ng
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
| | - Matthew W Gilmour
- National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
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13
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Eiler A, Johansson M, Bertilsson S. Environmental influences on Vibrio populations in northern temperate and boreal coastal waters (Baltic and Skagerrak Seas). Appl Environ Microbiol 2006; 72:6004-11. [PMID: 16957222 PMCID: PMC1563599 DOI: 10.1128/aem.00917-06] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Even if many Vibrio spp. are endemic to coastal waters, their distribution in northern temperate and boreal waters is poorly studied. To identify environmental factors regulating Vibrio populations in a salinity gradient along the Swedish coastline, we combined Vibrio-specific quantitative competitive PCR with denaturant gradient gel electrophoresis-based genotyping. The total Vibrio abundance ranged from 4 x 10(3) to 9.6 x 10(4) cells liter(-1), with the highest abundances in the more saline waters of the Skagerrak Sea. Several Vibrio populations were present throughout the salinity gradient, with abundances of single populations ranging from 5 x 10(2) to 7 x 10(4) cells liter(-1). Clear differences were observed along the salinity gradient, where three populations dominated the more saline waters of the Skagerrak Sea and two populations containing mainly representatives of V. anguillarum and V. aestuarianus genotypes were abundant in the brackish waters of the Baltic Sea. Our results suggest that this apparent niche separation within the genus Vibrio may also be influenced by alternate factors such as nutrient levels and high abundances of dinoflagellates. A V. cholerae/V. mimicus population was detected in more than 50% of the samples, with abundances exceeding 10(3) cells liter(-1), even in the cold (annual average water temperature of around 5 degrees C) and low-salinity (2 to 4 per thousand) samples from the Bothnian Bay (latitude, 65 degrees N). The unsuspected and widespread occurrence of this population in temperate and boreal coastal waters suggests that potential Vibrio pathogens may also be endemic to cold and brackish waters and hence may represent a previously overlooked health hazard.
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Affiliation(s)
- Alexander Eiler
- Limnology/Department of Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Norbyv. 20, SE-75236 Uppsala, Sweden
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14
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Kumar HS, Parvathi A, Karunasagar I, Karunasagar I. A gyrB-based PCR for the detection of Vibrio vulnificus and its application for direct detection of this pathogen in oyster enrichment broths. Int J Food Microbiol 2006; 111:216-20. [PMID: 16854484 DOI: 10.1016/j.ijfoodmicro.2006.05.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Revised: 04/08/2006] [Accepted: 05/14/2006] [Indexed: 10/24/2022]
Abstract
A polymerase chain reaction (PCR) method based on the gyrB (encoding gyrase B or topoisomerase II) gene sequence was developed for the detection of Vibrio vulnificus in seafood. The gyrB primers detected all laboratory isolates of V. vulnificus and did not cross react with other Vibiro and non-Vibrio species examined in this study. The sensitivity of detection of V. vulnificus by gyrB PCR was 300 CFU/g in artificially seeded oyster homogenate without enrichment while, 30 CFU/g could be detected following 18 h enrichment in alkaline peptone water (APW). The gyrB-specific PCR was employed for the direct detection of V. vulnificus in oyster enrichment broths. The assay detected V. vulnificus in 75% of natural oyster samples after 18 h enrichment in APW. The gyrB-based PCR described here offers a simple and specific one step PCR method for the detection of V. vulnificus in seafood enrichment broths.
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Affiliation(s)
- H Sanath Kumar
- Department of Fishery Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore 575 002, India
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