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Beta (β) Lactamase Test – Principle, Procedure, Results

Last Updated July 5, 2024 0 revisions 18 min readby BNO Team

Many bacteria produce a group of enzymes known as beta-lactamases that are mediated through genes in plasmids or the chromosomes. Beta-lactamase can be a constant process or it may be triggered through contact with antimicrobials. Beta-lactamases hydrolyze (and consequently inhibit) the beta-lactam ring of many Cephalosporins as well as penicillins. Beta-Lactamase Test is a rapid test to determine the presence of beta-lactamase , an enzyme that is produced by the strains from Staphylococcus aureus Neisseria gonorrhoeae, Branhamella catarrhalis as well as Haemophilus influenzae.

PYR Test (Pyrrolidonyl Arylamidase (PYR) test) – Principle, Procedure, Result

Published on May 12, 2024 7 min readby BNO Team

Principle of PYR Test Purpose of PYR Test Procedure of PYR Test The PYR examination is accessible in many versions. The original PYR test took 16 to 20 hours, but a 4-hour broth assay is now available, as reported in this post. Other forms include quick (10-15 minute) assays in which organisms to be evaluated … Read more

Urease Test – Principle, Procedure, Result

Published on May 12, 2024 11 min readby BNO Team

What is Urease Test? Purpose of Urease Test Principle of Urease Test (NH2)2CO + H2O → CO2 + 2NH3 Media Used for Urease Test Two types of media are typically employed to detect urease activity. Christensen’s urea agar is employed to identify urease activity in numerous bacteria. Stuart’s urea broth is largely used to distinguish … Read more

Nitrite Reduction Test – Principle, Procedure, Result

Published on May 12, 2024 10 min readby BNO Team

Principle of Nitrite Reduction Test Nitrites combine with an acidic solution of sulfanilic acid and alpha-naphthylamine to produce a red azo dye. In each test reaction, the appearance of the red dye shows the presence of NO2- in the test tube, either as an unreduced main substrate, a product of the test organism’s reduction of … Read more

Esculin Hydrolysis test Principle, Procedure, Result

Published on May 12, 2024 8 min readby BNO Team

Test Name Esculin Hydrolysis test Purpose This test is used to try to figure out what kind of Enterobacteriaceae it is and how it differs from other kinds.To see if the microbe can use esculin as a source of carbon by breaking it down with water. Media Required Esculin Hydrolysis Agar Result Positive: Blackened medium, … Read more

Gram-Sure (L-Alanine-7-amido-4-methylcourmarin) Test

Published on May 12, 2024 3 min readby BNO Team

Purpose of Gram-Sure Test Principle of Gram-Sure Gram-negative organisms’ cell walls include aminopeptidase, which can be identified through the hydrolysis of L-alanine-7-amido-4-methylcoumarin, a nonfluorescent substrate, into a fluorescent product. Materials Required Quality Control All Gram-Sure lot numbers were tested with the following quality control organisms and determined to be acceptable. The examination of control organisms … Read more

Deoxyribonuclease (DNase) Test – Principle, Procedure, Result

Published on May 12, 2024 14 min readby BNO Team

Test Name Deoxyribonuclease (DNase) Test Detection DNases enzyme Uses To find out if an organism can break down DNA and use it to get carbon and energy so it can grow.To distinguish Staphylococcus aureus from other Staphylococci. Result DNase Test Agar: After adding 1N HCl, a clear zone forms around the growth line, but the … Read more

Cetrimide Test – Principle, Purpose, Procedure, Results

Published on May 12, 2024 9 min readby BNO Team

Cetrimide Selective Agar is a solid medium that is recommended for use in qualitative procedures for selective isolation and presumed identification of Pseudomonas aeruginosa and other nonfermenting, gram-negative bacilli.

Casein Hydrolysis Test – Principle, Procedure, Result

Published on May 12, 2024 7 min readby BNO Team

Test Name Casein Hydrolysis Test Detection Enzyme caseinase producing microorganisms Uses To show that some microorganisms can make enzymes outside of their cells that can break down the milk protein casein. Result A clear, transparent zone can be seen around the area where the colonies are growing, or sometimes under the area where the colonies … Read more

Butyrate Disk Test – Principle, Procedure, Result

Published on May 12, 2024 6 min readby BNO Team

Overview of Butyrate Test Test Name Butyrate Disk Test Detection Enzyme butyrate esterase Uses This is a quick way to find out if Moraxella catarrhalis has the enzyme butyrate esterase. Result A blue colour development Require Bromochloro-indolyl butyrate and 4-methylumbelliferyl impregnated discs Test Organism Moraxella catarrhalis ATCC 25240: butyrate positive Butyrate Disk Test Purpose Principle … Read more