Journal of Food Science and Technology

, Volume 54, Issue 3, pp 786–791 | Cite as

Occurrence of clinical genotype Vibrio vulnificus in clam samples in Mangalore, Southwest coast of India

  • M. S. Sangeetha
  • Malathi Shekar
  • M. N. Venugopal
Original Article


Vibrio vulnificus is an opportunistic human pathogen causing gastroenteritis, wound infection and primary septicemia. V. vulnificus population has been divided into subpopulations based on their phenotype and genotype characteristics. In this study, 38.5% (10/26) of clam (Meretrix meretrix) samples obtained from Mangalore markets were seen to harbor V. vulnificus. Biochemical characterization of V. vulnificus isolates showed the strains to belong to Biotype 1 phenotype. Genotyping of strains using the 16S rRNA and virulence correlated gene (vcg) typing methods identified the isolates to be of 16S rRNA typeB and vcgC type respectively. Analysis of representative 16S rRNA and vcg gene sequences further substantiated that the V. vulnificus associated with clams in the present study to be of clinical origin, implicated as virulent type responsible for causing infection in humans.


Vibrio vulnificus Clinical genotype Biotype 1 vcgC gene 16S rRNA typeB Clams 



The first author acknowledges the funding received by UGC Rajiv Gandhi National Fellowship Scheme (RGNF-2013-14-SC-KER-48760) to carry out this study. The authors acknowledge the DBT-Bioinformatics Centre, KVAFSU, College of Fisheries Mangalore for carrying out the sequence analysis work.


  1. Al-Assafi MMK, Mutalib SA, Ghani MA, Mohammed A (2014) A review of important virulence factors of Vibrio vulnificus. Curr Res J Biol Sci 6:76–88Google Scholar
  2. Alsina M, Blanch AR (1994) A set of keys for biochemical identification of Vibrio species. J Appl Microbiol 1:79–85Google Scholar
  3. Arias CR, Pujalte MJ, Gary E, Aznar R (1998) Genetic relatedness among environmental, clinical, and diseased eel Vibrio vulnificus isolates from different geographic regions by ribotyping and randomly amplified polymorphic DNA PCR. Appl Environ Microbiol 64:3403–3410Google Scholar
  4. Ausubel FM, Brent R, Kingston RE, Moore DD, Seidman JG, Smith JA, Struhl K (1995) Short protocols in molecular biology. Wiley, New York, Ch. 2.4Google Scholar
  5. Aznar R, Ludwig W, Amann RI, Schleifer KH (1994) Sequence determination of rRNA genes of pathogenic Vibrio species and whole cell identification of Vibrio vulnificus with rRNA-targeted oligonucleotide probes. Int J Syst Bacteriol 44:330–337CrossRefGoogle Scholar
  6. Bier N, Bechlars S, Diescher S, Klein F, Hauk G, Duty O, Strauch E, Dieckmann R (2013) Genotypic diversity and virulence characteristics of clinical and environmental Vibrio vulnificus isolates from the Baltic sea region. Appl Environ Microbiol 79:3570–3581CrossRefGoogle Scholar
  7. Biosca EG, Oliver JD, Amaro C (1996) Phenotypic characterization of Vibrio vulnificus biotype 2, a lipopolysaccharide based homogeneous O serogroup within Vibrio vulnificus. Lett Appl Microbiol 22:184–188CrossRefGoogle Scholar
  8. Bisharat N, Daniel IC, Rosalind MH, Daniel F, Derrick WC, Tim P, Martin MC (2005) Hybrid Vibrio vulnificus. Emerg Infect Dis 11:30–35CrossRefGoogle Scholar
  9. Chase E, Harwood VJ (2011) Comparison of the effects of environmental parameters on growth rates of Vibrio vulnificus biotypes I, II, and III by culture and quantitative PCR analysis. Appl Environ Microbiol 77:4200–4207CrossRefGoogle Scholar
  10. Chatzidaki-Livanis M, Hubbard MA, Gordon K, Harwood VJ, Wright AC (2006) Genetic distinctions between clinical and environmental strains of Vibrio vulnificus. Appl Environ Microbiol 72:6136–6141CrossRefGoogle Scholar
  11. Cohen ALV, Oliver JD, Depaola A, Feil EJ, Boyd EF (2007) Emergence of a virulent clade of Vibrio vulnificus and the correlations with the presence of a 33-kilobase genomic island. Appl Environ Microbiol 73:5553–5565CrossRefGoogle Scholar
  12. FAO/WHO (2005) Risk assessment of Vibrio vulnificus in raw oysters-Interpretative summary and technical report. Microbiological risk assessment series, 8th edn, p 17Google Scholar
  13. Food and Drug Administration (2000) Bacteriological analytical manual, Food and Drug Administration, 7th edn. AOAC International, Arlington, pp 383–419Google Scholar
  14. Guerrero A, Gómez Gil Rodríguez B, Wong-Chang I, Lizárraga-Partida ML (2015) Characterization of clinical and environmental types of Vibrio vulnificus isolates from Louisiana oysters. Foodborne Pathog Dis 6:1251–1258Google Scholar
  15. Gulig PA, Bourdage KL, Starks AM (2005) Molecular pathogenesis of Vibrio vulnificus. J Microbiol 43:118–131Google Scholar
  16. Han F, Pu S, Hou A, Ge B (2009) Characterization of clinical and environmental types of Vibrio vulnificus isolates from Louisiana oysters. Foodborne Pathog Dis 6:1251–1258CrossRefGoogle Scholar
  17. Kim MS, Jeong HD (2001) Development of 16S rRNA targeted PCR methods for the detection and differentiation of Vibrio vulnificus in marine environments. Aquaculture 193:199–211CrossRefGoogle Scholar
  18. Lee SE, Kim SY, Kim SJ, Kim HS, Shin JH, Choi SH, Chung SS, Rhee JH (1998) Direct identification of Vibrio vulnificus in clinical specimens by nested PCR. J Clin Microbiol 36:2887–2892Google Scholar
  19. Morrison SS, Cain A, Froelich B, Williams T, Taylor C, Baker-Austin C, Verners-Jeffreys D, Hartnell R, Oliver JD, Gibas CJ (2012) Pyrosequencing based comparative genome analysis of Vibrio vulnificus environmental isolates. PLoS ONE 7:e37553CrossRefGoogle Scholar
  20. Nilsson WB, Paranjype RN, Depaola A, Strom MS (2003) Sequence polymorphism of the 16S rRNA gene of Vibrio vulnificus is a possible indicator of strain virulence. J Clin Microbiol 41:442–446CrossRefGoogle Scholar
  21. Oliver JD (2015) The biology of Vibrio vulnificus. Microbiol spectr 3:1–10Google Scholar
  22. Reynaud Y, Steven P, Sophie DD, Gary HW, Christopher LB (2013) Molecular typing of environmental and clinical strains of Vibrio vulnificus isolated in the north-eastern USA. PLoS ONE 8:e83357CrossRefGoogle Scholar
  23. Rosche TM, Yano Y, Oliver JD (2005) A rapid and simple PCR analysis indicates there are two subgroups of Vibrio vulnificus which correlate with clinical or environmental isolation. Microbiol Immunol 49:381–389CrossRefGoogle Scholar
  24. Rosche TM, Binder EA, Oliver JD (2010) Vibrio vulnificus genome suggests two distinct ecotypes. Environ Microb Rep 2:128–132CrossRefGoogle Scholar
  25. Stelma GM, Jr Reyes AL, Peeler JT, Johnson CH, Spaulding PL (1992) Virulence characteristics of clinical and environmental isolates of Vibrio vulnificus. Appl Environ Microbiol 58:2776–2782Google Scholar
  26. Van de Peer Y, Nicolai S, De Rijk P, De Wachter R (1996) Database on the structure of small ribosomal subunit RNA. Nucleic Acids Res 24:86–91CrossRefGoogle Scholar
  27. Warner EB, Oliver JD (2008a) Multiples PCR assay for detection and simultaneous differentiation of genotypes of Vibrio vulnificus biotype1. Foodborn Pathog Dis 5:691–693CrossRefGoogle Scholar
  28. Warner EB, Oliver JD (2008b) Population structure of two genotypes of Vibrio vulnificus in oysters (Crassostrea virginica) and seawater. Appl Environ Microbiol 74:80–85CrossRefGoogle Scholar

Copyright information

© Association of Food Scientists & Technologists (India) 2017

Authors and Affiliations

  • M. S. Sangeetha
    • 1
  • Malathi Shekar
    • 1
  • M. N. Venugopal
    • 1
  1. 1.Department of Fisheries Microbiology, College of FisheriesKarnataka Veterinary, Animal and Fisheries Sciences UniversityMangaloreIndia

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