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What test will differentiate between Klebsiella pneumonia and Citrobacter freundii?
K. oxytoca will be indole-positive while K. pneumonia is indole-negative
What are the indole test principles?
this test is done to determine if bacteria can breakdown the amino acid tryptophan into indole
Does escherichia coli give a negative result for citrate test?
No, it is present/positive. • Cocci* • Gram-Positive* • Non-motile* • No Capsules* • No Spores* • Facultative Aerobe* • No Glucose, Lactose*, Mannitol* Fermentation • No Urease*, Catalase*, Oxidase*, Ligase*, Protease* Production • Production of Indole*, tryptophonase*
Microbiology - what is SIM test?
Its a test where a semisolid agar called Sulfide-Indole-Motility medium (or SIM medium) is inoculated with a bacteria to test for hydrogen Sulfide, Indole, and Motility of the organism. The medium is inoculated by a swab and stab type method (rub some bacteria on the surface of the medium and stab a straight hole through the medium using a straight wire with the bacteria on it). Incubate the bacteria for about 24 hours and then begin testing.... If hydrogen sulfide is present, it will react with the sodium thiosulfate in the medium and the indicator, ferric ammonium citrate, to produce ferrous sulfide which falls out of solution as a blackish precipitate. The presence of hydrogen sulfide typically means that the bacteria produces the enzyme cysteine desulfanase which breaks up the cysteine in the medium into, among other components, hydrogen sulfide. The Indole portion of the test is performed by adding Kovac's reagent to the inoculated medium. The Kovac's reagent reacts with the indole(if indole is present) to produce a pinkish-red or redish-purple ring around the top of the test tube. If indole isn't present, there will be no color change. The presence of indole means that the bacteria produces tryptophanase, an enzyme which breaks down tryptophan into smaller components, one of which being indole. The Motility aspect of the test is done by checking the medium for turbidity, or "fuzziness". If the medium has become fairly turbid throughout the medium, then the bacteria is motile. If the medium is clear and the only turbid appearance is in the stab line, then the bacteria is non-motile. Unfortunately, the motility aspect of this test typically gives false negative results. Sometimes the temperature that the bacteria was incubated at wasn't optimum for the species, sometimes the bacteria only have weak motility, sometimes the bacteria's flagella can get damaged which would impair motility, etc... The point is, this test is good if you want to know whether or not the bacteria you're testing produces tryptophanase or cysteine desulfanase. The motility aspect of the test is suspect to question, at least if the test result was negative for motility(a large amount of turbidity in the medium is a definite sign of motility and is hard to refute though).
What is the best biochemical test to identify gram negative and H2S bacilli?
Gram Stain to determine gram negative and shape or streak on a Agar plate selective for gram negative such as Desoxycholate Agar (DES). A SIM (Sulfur, Indole, Motility) Test or a Kiliger's Iron Agar (KIA) Test can confirm the production of H2S. *I would choose Streaking on DES to isolate the gram Negative bacteria, and then stab inoculate a SIM tube. Black precipitate confirms H2S production positive.
What are the results for a capsule stain for alcaligenes faecalis?
I dont have any answer, But i will post it when i will know . No change in color or reaction on Indole Test - Negative result on Indole Test.
What test will differentiate between Proteus vulgaris and Citrobacter freundii?
Indole test,Proteus vulgaris is be indole positive and Citrobacter freundii will be indole negative
What is Staphylococcus aureus sim test results?
Staphylococcus aureus is negative for motility, and positive for the indole production. The SIM test tests for sulfur reduction, indole production and motility. Positive for indole production means tryptophan is broken down into indole and pyruvate and will give a red color. Motility, you will see the bacteria move outside of the stab. Positive for sulfur reduction will give a black color in the medium.
Is staphylococcus epidermidis indole positive?
S.aureus is a positive gram. Indole test is a part the biochemistry test to determinate a bacteria negative gram. indole test used to determine S.aureus, the result is negative. That is improve which S.aureus haven't trytophanase enzym (please see indole test principle)bcb
What are results of Imvic test on staphylococci?
Staphylococcus epidermidis indole test - negative methyl red - negative voges proskauer test - positive citrate test - no idea
What test will differentiate between Klebsiella pneumonia and Citrobacter freundii?
K. oxytoca will be indole-positive while K. pneumonia is indole-negative
What does the S.I.M. test for?
Sulfur Indole Motility test
Indole test in vibro cholera?
The indole positive test is used to test the absence or presence of the vibro cholera.
What are the indole test principles?
this test is done to determine if bacteria can breakdown the amino acid tryptophan into indole
Why is it important to incubate your culture for more than 5 days when performing the indole test?
If incubation surpasses 5 days, the bacteria may degrade indole to the point that a FALSE negative would result.
What is the substrate for the Indole test?
The indole test is a biochemical test performed on bacterial species to determine the ability of the organism to split indole from the amino acid tryptophan. This division is performed by a chain of a number of different intracellular enzymes, a system generally referred to as "tryptophanase."
Organism which is citrate positive indole negative MR negative VP negative sorbitol negative?
Klebsiella sp.
