Citrate Utilization Test- Principle, Procedure, Results, Uses


Citrate utilization test is a biochemical test that determines whether a bacterium can use citrate as its sole source of carbon and energy. Citrate is a tricarboxylic acid that is an intermediate in the Krebs cycle, a metabolic pathway that generates energy from carbohydrates, fats, and proteins. Some bacteria have the ability to ferment citrate in the presence of an enzyme called citrase, which breaks down citrate into oxaloacetate and acetate. These bacteria can grow on a medium that contains citrate as the only carbon source and ammonium salts as the only nitrogen source.

Citrate utilization test is one of the four tests that make up the IMViC test, which stands for Indole, Methyl Red, Voges-Proskauer, and Citrate test. The IMViC test is a set of biochemical tests that are used to differentiate Gram-negative bacilli of the Enterobacteriaceae family, which includes many medically important bacteria such as Escherichia coli, Salmonella typhi, Shigella dysenteriae, and Klebsiella pneumoniae. The IMViC test is based on the different metabolic reactions of these bacteria to various substrates and indicators.