Biochemical Test

Phenylalanine Deaminase Test

Result Interpretation of Phenylalanine Deaminase Test

Phenylalanine Deaminase Test Objectives of Phenylalanine Deaminase Test To determine the ability of an organism to oxidatively deaminate phenylalanine to phenylpyruvic acid. To differentiate enteric Gram-nega­tive bacilli on the basis of their ability to produce phenylpyruvic acid from phenylalanine. Principle of Phenylalanine Deaminase Test Phenylalanine deaminase medium tests the ability of an organism to produce the enzyme … Read morePhenylalanine Deaminase Test

Triple Sugar Iron Agar (TSIA) Test

Result Interpretation of TSIA Test

Triple Sugar Iron Agar (TSIA) Test Objectives of TSIA Test To determine whether a gram negative bacilli ferments glucose and lactose or sucrose and forms hydrogen sulfide (H2S). To differentiate members of the Enterobacteriaceae family from other gram-negative rods. Principle of TSIA Test The Triple Sugar Iron agar (TSIA) test is designed to differentiate among … Read moreTriple Sugar Iron Agar (TSIA) Test

Casein Hydrolysis Test

Result of Casein Hydrolysis Test

Casein Hydrolysis Test Objectives of Casein Hydrolysis Test To determine the ability of the organism to degrade the casein protein. To differentiate the organism on the basis of production of exoenzyme proteinase (caseinase) Principle of Casein Hydrolysis Test Casein is a macromolecule composed of amino acids linked together by peptide bonds, CO-NH. Some microorganism have the ability … Read moreCasein Hydrolysis Test

Bile Esculin Test

Bile Esculin Test

Bile Esculin Test Objectives of Bile Esculin Test To identify Enterococci and group D Streptococci based on the ability of an organism to hydrolyze esculin in presence of bile. To differentiates enterococci and group D streptococci from non–group D viridans streptococci. Principle of Bile Esculin Test Esculin is a glycoside (a sugar molecule bonded by an acetyl linkage … Read moreBile Esculin Test

Beta (β)-Lactamase Test- Objectives, Principle, Procedure and Results

Result Interpretation of Beta (β)-Lactamase Test

Objective of Beta (β)-Lactamase Test To detect the enzyme beta-lactamase, which confers penicillin resistance to various bacterial organisms. Principle of Beta (β)-Lactamase Test Various bacteria produce a class of enzymes called beta-lactamases, which may be mediated by genes on plasmids or chromosomes. Production of beta-lactamase may be constitutive or induced by exposure to antimicrobials. Beta-lactamases hydrolyze (and thereby inactivate) … Read moreBeta (β)-Lactamase Test- Objectives, Principle, Procedure and Results

X and V Factor Test for Haemophilus

X and V Factor Test for Haemophilus

Objective of X and V Factor Test To differentiate among Haemophilus species based on X and V factor required for growth. Principle of X and V Factor Test Haemophilus spp. have varying requirements for X and V growth factors. X factor indicates hemin and V factor indicates nicotinamide-adenine-dinucleotide, NAD. Consequently, the significant differences in growth factor … Read moreX and V Factor Test for Haemophilus

Voges Proskauer (VP) Test

Result Interpretation of VP Test

Objective of VP Test To differentiate two major types of facultative anaerobic enteric bacteria based on production of neutral products. Principle of VP Test Voges Proskauer test, commonly known as VP test is used to determine the ability of some organisms to produce neutral end products (e.g., 2, 3-butanediol or acetoin) from glucose fermentation. All members … Read moreVoges Proskauer (VP) Test

L-Pyrrolidonyl Arylamidase (PYR) Test

Result Interpretation of PYR Test

Objectives of PYR Test To determine the ability of organism to produce L-pyrrolidonyl arylamidase enzyme. It aids in the presumptive identification of group A streptococci (Streptococcus pyogenes) and Enterococci by the presence of the enzyme L-pyrrolidonyl arylamidase. Principle of PYR Test Pyrrolidonyl Arylamidase (PYR) test is a rapid test which is used for the presumptive identification … Read moreL-Pyrrolidonyl Arylamidase (PYR) Test

Spot Indole Test- Objective, Principle, Procedure, Results and Limitations

Result Interpretation of Spot Indole Test

Objective of Spot Indole Test To determine the ability of organism for the production of indole by the action of tryptophanase enzyme. Principle of Spot Indole Test Intracellular enzyme tryptophanase mediate the production of indole by hydrolytic activity against amino acid Tryptophan. Bacteria that produce the enzyme tryptophanase are able to degrade the amino acid tryptophan into … Read moreSpot Indole Test- Objective, Principle, Procedure, Results and Limitations

Starch Hydrolysis Test- Objectives, Principle, Procedure and Results

Result interpretation of Starch Hydrolysis Test

Objectives of Starch Hydrolysis Test To determine the ability of the organism capable of hydrolyzing starch. To differentiate organism based on their ability to hydrolyze starch with the enzyme, α- amylase. It aids in the differentiation of species from genera Corynebacterium, Clostridium, Bacillus, Bacteroides, Fusobacterium, and members of Enterococcus. Principle of Starch Hydrolysis Test Starch is a complex … Read moreStarch Hydrolysis Test- Objectives, Principle, Procedure and Results