Physiological Tests etc.

Methyl Red-Voges Proskauer (MR-VP)

fermentation test

red is positive

glucose fermentation test

fermentation test

yellow is positive

tryptophan degradation test

reagent: kovac’s reagent

positive is red

casein hydrolysis

citrate utilization test

fermentation test

blue is positive

oxidase test

oxidative test

reagent: oxidase reagent

aerobic cellular respiration!!!

purple is pos

starch hydrolysis

reagent: gram’s iodine

catalase test

oxidative test

reagent: hydrogen peroxide

bubbles pos

phenylalanine deamination test

ferric chloride reagent

blue is pos

urea hydrolysis

pink is pos

lipid hydrolysis

spirit blue agar

no reagents

dark blue pos

nitrate reduction test

oxidative test

reagents: nitrate reagent A, nitrate reagent B, zinc

pos is red after nitrate reagents A and B OR colorless after nitrate reagents A and B and zinc

SIM test

s = sulfide, I = indole, M = motility

pos for S is black

pos for indole is pink ring

pos for motility is cloudiness

kligler’s iron agar

all yellow = glucose and lactose fermentation

red slant = only glucose

all red = no fermentation

black = sulfide production, yellow butt under (because it needs an acidic enviorment)

b. subtils positive tests?

starch hydrolysis

caesin hydrolysis

e. coli positive tests?

tryptophan degradation

kligler’s iron agar (all yellow + gas production)

glucose fermentation

p. vulgaris positive tests?

kligler’s iron agar for hydrogen sulfide (and glucose fermentation)

SIM test (all)

urea hydrolysis

what are the two selective media for s. aureus? explain positive results. what makes these media selective?

MSA: selective due to high salt concentration; differential because s. aureus ferments mannitol making it yellow

SM110: selective due to high salt concentration; differential because s. aureus shows up golden due to a pigment staphyloxanthin