Question

Good growth occurs on blood agar after enrichment in alkaline peptone water. It is beta hemolytic on blood agar. On TCBS media, colonies will appear yellow. On MacConkey agar the colonies are colorless or may show a pale pink to tan pigment. It grows on most enteric media. The bacterial cells are gram-negative, short, straight or typically curved comma-shaped bacilli. Biochemical results are: oxidase positive, motility positive, esculin hydrolysis negative, citrate positive, VP negative, string test positive and sucrose positive.

Answer 1

Answer-

According to the given question-

Identification of any microorganism starts from gram staining followed by morphology detection. So here we have bacteria which is gram negative and do not retain crystal violet dye in their cell wall. Morphological identification we get it is straight, short, or comma-shaped bacilli.When grown on Thiosulfate-Citrate-Bile Salts-Sucrose or TCBS Agar it ferment sucrose and turn the medium yellow. in this medium peptone provide vitamins, nitrogen, and amino acids source . when grown on MacConkey agar the colony are colorless because the bacteria cannot ferment lactose and remain colorless. On blood agar it show clear zone which means that completely hydrolysis occur and gives positive results . other Biochemical results which are positive are oxidase, motility, sucrose , citrate , but show negative results for esculin hydrolysis and VP.

This bacteria is Vibrio cholerae

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