Assays Flashcards
What biochemical assay is this? What does it test for?
Carbohydrate Fermentation (phenol red broth); ability to ferment carbohydrate, causing acid production and possibly gas production
What is the test result for the first tube, what does this mean?
-(K)/- Alkaline (deamination occurred) no gas production
What is the test result for the middle tube, what does this mean?
A/- Fermentation w/o gas production
What is the test result for the third tube, what does this mean?
A/G Fermentation w/gas production
What biochemical assay is this? What does it test for?
Bile Esculin Agar; ability to hydrolyze esculin in the presence of bile
Interprete results for both tubes
left is negative, right (more than half black in 48hrs) is postive
What is the reagent for Oxidase Test? What does it test for? What are the results?
Oxidase reagent; tests for presence of oxidase; turns purple in 15sec for G-, 60sec for G+
What does a catalase test use for reagent, what does it test for, what is a positive result?
H2O2; presence of catalase; gas bubbles
What does an anaerobic culture jar test for? What is a positive result?
ability to grow in the absence of oxygen; growth
SIM: Sulfer reduction tests for what?, what reagent is used? what is a positive result?
Sulfur reduction to H2S; no reagent; an amount of blackening
SIM: Indole tests for? What reagents? What is a positive result?
Presence of tryptophanase; Kovacs’ Reagent; red
SIM: Motility tests for? What reagents are used? What is a positive result?
motility; no reagents; growth radiating from the stab line/cloudiness in the media
What test is this?
SIM (sulfur, indole, motility)
What test is this? What does it test for?
Nitrate Reduction Test; reduction of nitrate
What is the reagent for phase 1? what are the results?
none; bubble in durham tube for non-fermentor is +
What is the reagent for Phase two of Nitrate Reduction? What are the results?
sulfanilic acid and alpha-naphthylamine; red color indicates nitrite +
What is the reagent for phase 3 of nitrate reduction, what are the results?
powdered zinc; if nitrate is still present it will be reduced by the zinc, red color indicates neg result (no color change is pos)
What test is this? what does it test for? What reagent is used?
Methyl Red (MR); glucose fermention by mixed-acid fermentation pathway; methyl red
Interpret the results
a-positive, b-negative (orange would be inconclusive)
What test is this? What does it test for? What reagents are used?
Voges-Proskaur (VP); KOH and alpha-naphathol; glucose fermentation via the 2,3-butanediol pathway
Interpret the results of this VP test
left-negative, right-positive
What test is this, what does it test for? What reagents? Interpret results.
Simmons Citrate, ability to utilize citrate as carbon source; none; left (green)-negative, right (blue)-positive
What is this? What does it test for? What are the results?
gelatinase; ability to hydrolyze gelatin; Liquid at low temp is positive result
What test is this? What does it test for? What reagents? Interprete results
Urease Agar; ability to hydrolyze urea to produce ammonia; none; left-negative, right-positive
