The Kanagawa phenomenon, regarded as a marker of pathogenicity in Vibrio parahaemolyticus, refers to:

• A Yellow colony color on TCBS agar due to sucrose fermentation
• B Swarming growth over the surface of blood agar at 37 degrees Celsius
• C Beta-hemolysis on Wagatsuma agar produced by thermostable direct hemolysin ✓
• D String-like mucoviscous colony morphology on MacConkey agar

Explanation

The Kanagawa phenomenon is beta-hemolysis of human red blood cells on Wagatsuma agar, mediated by the thermostable direct hemolysin (TDH). Virtually all clinical isolates of V. parahaemolyticus are Kanagawa positive, whereas environmental isolates are mostly negative, making it a reliable marker of enteropathogenicity. Swarming is characteristic of Proteus, yellow colonies on TCBS indicate sucrose fermentation by V. cholerae, and the string test denotes hypermucoviscous Klebsiella.

Reference: Ananthanarayan and Paniker Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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