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Updated: Sep 15, 2026

Development of a More Sensitive and Specific Chromogenic Agar Medium for the Detection of Vibrio parahaemolyticus and Other Vibrio Species
09:34

Development of a More Sensitive and Specific Chromogenic Agar Medium for the Detection of Vibrio parahaemolyticus and Other Vibrio Species

Published on: November 8, 2016

Hemolytic activity of and lethal toxin production by environmental strains of Vibrio parahaemolyticus

B L Sarkar1, R Kumar, S P De

  • 1National Institute of Cholera and Enteric Diseases, Beliaghata, Calcutta, India.

Applied and Environmental Microbiology
|November 1, 1987
PubMed

Insights

Kanagawa-negative Vibrio parahaemolyticus strains produced a novel hemolysin. This hemolysin showed lethal toxicity in mice, indicating environmental strains contribute to pathogenesis.

Area of Science:

  • Microbiology
  • Bacteriology
  • Pathogenesis Research

Background:

  • Vibrio parahaemolyticus is a significant foodborne pathogen.
  • Kanagawa-negative strains are typically considered non-pathogenic.
  • Understanding hemolysin production in environmental isolates is crucial.

Purpose of the Study:

  • To investigate hemolysin production in Kanagawa-negative Vibrio parahaemolyticus strains.
  • To characterize the induced hemolysin and its toxicity.
  • To assess the pathogenic potential of environmental V. parahaemolyticus isolates.

Main Methods:

  • Repeated subculturing of Kanagawa-negative Vibrio parahaemolyticus on Wagatsuma agar.
  • Induction and partial characterization of hemolysin.
  • Toxicity testing in mice via intraperitoneal injection.
  • Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for protein analysis.

Main Results:

  • Subculturing induced hemolysin production in Kanagawa-negative strains.
  • The induced hemolysin was distinct from thermostable direct hemolysin.
  • Crude hemolysin demonstrated 30-40% lethal toxicity in mouse models.
  • SDS-PAGE revealed a consistent 21-kilodalton protein band in environmental isolates.

Conclusions:

  • Kanagawa-negative Vibrio parahaemolyticus can produce pathogenic hemolysins under specific conditions.
  • Environmental strains of V. parahaemolyticus possess the potential for pathogenesis.
  • A 21 kDa protein may be associated with the induced hemolysin activity.

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