ABSTRACT
Vibrio cholerae is a gram-negative, facultatively anaerobic, curved rod that is polarly agellated, cytochrome oxidase-positive, and characteristically ferments glucose to acid without gas production. The generally accepted method for its isolation involves enrichment in alkaline peptone water (APW) followed by culture on selective thiosulfate-citrate-bile salts-sucrose (TCBS) agar (Table 6.5, Chapter 6). Sucrose-positive, smooth yellow colonies on TCBS agar are submitted to the oxidase test. Positive colonies are then puried on a nonselective agar and subjected to biochemical and serological tests. Detection of cholera toxin (CTX) is usually by an ELISA assay.
