A Halophilic Vibrio Isolated from a Case of Chronic Cholecystitis

Abstract

We found a halophilic vibrio in B bile from a 75-year-old female patient with chronic cholecystitis, and examined its biochemical characteristics. The organisms are gram-negative short rods or comma shaped, with some ring forms. They have a single polar flagellum, but no capsule. The strains can grow in peptone water with 1.0 to 4.0% NaCI, but not with no NaCI or 6.0% NaCI. The characteristics of the organisms are positive dextrose fermentation, catalase, oxidase, and ornithine decarboxylase, and negative lysine decarboxylase, arginine dihydrolase, and absence of gas from glucose. They are sensitive to 2,4-diamine-6,7-diisopropyl pteridine (0/129). These characteristics indicate that the isolated strain should be a halophilic vibrio. However, no growth on Salmonella-Shigella (SS), SS with added sucrose and bromcresol purple (SS-SB), MacConkey's or thiosulfate citrate bile salts (TCBS) agar plates was demonstrated. Nitrate reduction, Simmons' citrate agar, indole, o-nitrophenol-p-d-galactopyranoside (ONPG), motility and esculin hydrolysis were positive. Urease, gelatinase, VogesProskauer, phenylalanine deaminase and malonate reactions were negative. Acid was produced from amygdalin, arabinose, cellobiose, fructose, galactose, glucose, lactose, maltose, mannitol, salicin, starch, sucrose, trehalose, and xylose, but not from adonitol, dulcitol, inositol, mannose, melibiose, raffinose, rhamnose and sorbitol. From these characteristics the isolate is considered to be not identical with V. parahaemolyticus, V. cholerae, V. oulnificus or other vibrios. It can be presumed that this isolate represents another species of halophilic vibrio.

Activation of Cholera Toxin Production by Anaerobic Respiration of Trimethylamine N-oxide in Vibrio cholerae

“…As a facultative anaerobe, V. cholerae can support its growth by fermentation of diverse carbohydrates including glucose, sucrose, maltose, mannitol, lactose, dextrin, and starch (12,13). Sucrose fermentation has been used as a basis for the identification of V. cholerae species among fecal isolates (14).…”