A positive gelatin liquefaction is characteristic of which organism?

Prepare for the Clinical Laboratory Science Bacteriology Test. Engage with multiple choice questions and flashcards with helpful hints and explanations. Ace your exam confidently!

Multiple Choice

A positive gelatin liquefaction is characteristic of which organism?

Explanation:
Gelatin liquefaction tests detect extracellular gelatinase, an enzyme that hydrolyzes gelatin in the medium. When an organism produces this enzyme, the solid gelatin becomes liquid during incubation and stays liquid after chilling, giving a positive result. Serratia liquefaciens is classically known to be gelatinase-positive, so it liquefies gelatin and yields a positive test. The other listed organisms are not the typical examples used to illustrate gelatin liquefaction in standard teaching, with Salmonella Typhimurium not normally showing this trait.

Gelatin liquefaction tests detect extracellular gelatinase, an enzyme that hydrolyzes gelatin in the medium. When an organism produces this enzyme, the solid gelatin becomes liquid during incubation and stays liquid after chilling, giving a positive result.

Serratia liquefaciens is classically known to be gelatinase-positive, so it liquefies gelatin and yields a positive test. The other listed organisms are not the typical examples used to illustrate gelatin liquefaction in standard teaching, with Salmonella Typhimurium not normally showing this trait.

Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy