What is the purpose of the IMViC test?
The IMViC tests are a group of individual tests used in microbiology lab testing to identify an organism in the coliform group. A coliform is a gram negative, aerobic, or facultative anaerobic rod, which produces gas from lactose within 48 hours. The presence of some coliforms indicate fecal contamination.
What is the principle of the indole test?
Principle of Indole Test Tryptophanase catalyzes the deamination reaction, during which the amine (-NH2) group of the tryptophan molecule is removed. Final products of the reaction are indole, pyruvic acid, ammonium (NH4+) and energy. Pyridoxal phosphate is required as a coenzyme.
How do you do the IMViC test?
Procedure: Bacterium to be tested is inoculated into glucose phosphate broth and incubated for at least 48 hours. 0.6 ml of alpha-naphthol is added to the test broth and shaken. 0.2 ml of 40% KOH is added to the broth and shaken. The tube is allowed to stand for 15 minutes.
Is IMViC a biochemical test?
IMVIC is a group of individual biochemical tests, used for the detection of coliform group. IMVIC test is the combination of four tests, such as Indol test, Methyl red test, Voges-Proskauer test, and Citrate utilization test. The indole test detects the production of indole from the amino acid tryptophan.
Is the IMViC test selective or differential?
The IMVIC series provides definitive differentiation of Escherichia coli and Enterobacter aerogenes in testing water potability. Why is such differentiation required? a. This media is both selective and differential.
What is the principle of citrate test?
When the bacteria metabolize citrate, the ammonium salts are broken down to ammonia, which increases alkalinity. The shift in pH turns the bromthymol blue indicator in the medium from green to blue above pH 7.6.
Why is the IMViC test useful in identifying Enterobacteriaceae?
What does the term IMViC mean? Why is the IMViC useful in identifying Enterobacteriaceae? IMViC is useful b/c it incorporates four tests to identify gram negative bacteria of Enterobacteriaceae. For complete identification, oxidase, ONPG, and urease tests can be used.
How many tests are in IMViC test Mcq?
To obtain the results of these four tests, three test tubes are inoculated: tryptone broth (indole test), methyl red – Voges Proskauer broth (MR-VP broth), and citrate. IMViC tests are employed in the identification/differentiation of members of family Enterobacteriaceae.
What is IMViC test?
IMVIC test is the combination of four tests, such as Indol test, Methyl red test, Voges-Proskauer test, and Citrate utilization test. The indole test detects the production of indole from the amino acid tryptophan.
What are IMViC reactions?
IMViC REACTIONS IMViC reactions are a set of four useful reactions that are commonly employed in the identification of members of family enterobacteriaceae. The four reactions are: Indole test, Methyl Red test, Voges Proskauer test and Citrate utilization test.
What do the letters in IMViC stand for?
Each of the letters in “IMViC” stands for one of these tests. “I” is for indole; “M” is for methyl red; “V” is for Voges-Proskauer, and “C” is for citrate, lowercase “i” is added for the ease of pronunciation.
What is the use of Kovac reagent in IMViC?
Kovac’s reagent is mainly used for the detection of the ability of an organism to separate indole from amino acid tryptophan and it is added after incubation. Methyl red and Voges–Proskauer is the second step of IMVIC test procedure.