dr lu5a

1. Biochemical Tests
Principles
Reagents & Media
Procedures & Results

3. IMViC
x Indole - x Methyl Red -
– product of hydrolysis – pH indicator
of tryptophan – production of
– Reagent - (Ehrlichs) sufficient acidity
Para-dimethyl- from glucose
aminobenzaldehyde – Media- MR-VP
– (+) pink or red color broth
– (+) red - acid
– (-) yellow - alkaline

5. IMViC (2)
x Vogues Proskauer - x Citrate Utilization Test
– production of – citrate as a source
acetyl-methyl of Carbon
carbinol from – media :Simmon
glucose Citrate (SCA)
– media: MR-VP – (+) blue color
broth – (-) green color
– reagent: 40% KOH
– (+) production of an
eosin like color

7. Biochemical Tests (3)
x Urease Test - x Oxidase Test -
– Hydrolysis of urea – catalysis of Oxidase
by Proteus sp. through cytochrome
– media: by N. gonorrhea
Christensen’s urea – media: CAP
– (+) Pink color media – reagent: 1% para-
/hemolysis amino-dimethyl-
– (-) colorless aniline hydrochloride
– (+) black

9. Biochemical Tests (4)
x Catalase Test - x Coagulase Test -
– decomposition of – coagulation of
3% Hydrogen plasma with enzyme
peroxide coagulase by
– (+) rapid evolution pathogenic
of gas staphylococcus
– organisms: – media: Blood plasma
y(+) staphylococci – (+) clotting of plasma
y micrococci
y (-) streptococci

11. Biochemical Tests (5)
x Hemolysis test - x Hydrogen Sulfide
– destruction of RBC test -
– media : Blood agar – production of
plate Hydrogen sulfide
– (+) clearing zone – any media with
x Greig’s Test Fe
– hemolysis of – (+) black ppt.
sheep’s rbc x Pigment formation
– (+) El tor (-) vibrio – chromogens

13. Enzymes produced by bacteria:
x Constitutive - essential enzymes
x Adaptive - non-essential enzymes
x Intracellular
x Extracellular