Enterobacteriaceae Cultural Characteristics

Enterobacteriaceae Cultural Characteristics

Image Source: Cole-Parmer Instrument Company. Cultural Characteristics of Citrobacter freundii Citrobacter freundii on Nutrient Agar Smooth, convex, translucent, or opaque grey colored with a shiny surface and entire margin; mucoid or rough colonies occasionally. Citrobacter freundii on Blood Agar Circular, flat, entire red colored colonies. Citrobacter freundii on Mac-Conkey Agar Pink colored after 24 hr … Read more Enterobacteriaceae Cultural Characteristics

Sulfur Reduction Test

Sulfur Reduction Test

Objectives To determine the ability of the organism to reduce sulfur for the production of hydrogen sulfide. To differentiate members of Enterobacteriaceae, especially the sulfur-reducing Salmonella and Proteus from the non-reducing Morganella morganii and Providencia rettgeri. Principle The Sulfur Reduction Test is performed using the SIM medium. SIM medium also tests for indole production and … Read more Sulfur Reduction Test

Decarboxylase Test- Principle, Procedure and Result Interpretation

Decarboxylase Test- Principle, Procedure and Result Interpretation

Decarboxylase Test- Principle, Procedure and Result Interpretation Objective of Decarboxylase Test This test is used to differentiate decarboxylase producing Enterobacteriaceae from other gram-negative rods. Principle of Decarboxylase Test This test measures the enzymatic ability (decarboxylase) of an organism to decarboxylate (or hydrolyze) an amino acid to form an amine. Decarboxylation, or hydrolysis, of the amino acid results … Read more Decarboxylase Test- Principle, Procedure and Result Interpretation

Citrate Utilization Test- Principle, Procedure and Result Interpretation

Citrate Utilization Test- Principle, Procedure and Result Interpretation

Citrate Utilization Test- Principle, Procedure and Result Interpretation Objectives of Citrate Utilization Test The purpose of this test is to identify organisms capable of using sodium citrate as the sole carbon source and inorganic ammonium salts as the sole nitrogen source. The test is part of a series referred to as IMViC (indole, methyl red, Voges-Proskauer, … Read more Citrate Utilization Test- Principle, Procedure and Result Interpretation