Metabolic tests 2: IMViC, TSI, catalase, bonus urease and coagulase; a few Metabolic tests part 1 (catalase, oxidase).

2 different bacteria, Microbe A (red color) and Microbe B (yellow color).

 

Which one of the microbes is "indole positive" and which enzyme does this microbe make that permits it to make indole?

 

Microbe A; tryptophanase

Methyl Red test results for 2 bacteria, Bacterium A and Bacterium B.

(Methyl Red) MR +

 

Does not carry out mixed acid fermentation

 

final pH ~4.4 or lower

 

Which microbe could be E. coli?

A

B

A

A

VP results for 2 bacteria, Bacterium C and Bacterium D

Which microbe could be E. coli?

 

Which microbe could be Enterobacter aerogenes?

 

Which microbe carries out 2,3-butanediol fermentation/butylene glycol fermentation?

 

Which microbe makes acetoin/acetylmethylcarbinol?

 

C

D

D

D

Simmon's Citrate Agar slants

A= uninoculated, green

B= Microbe B,  green

C= Microbe C, blue

Which microbe can use citrate as its sole source of carbon and energy?

 

Which microbe could be Enterobacter aerogenes?

C

C

TSI slants:

Presume tube C is the uninoculated control

This microbe makes hydrogen sulfide

 

This tube contains iron sulfide

 

This microbe ferments glucose only and does not make hydrogen sulfide

 

This microbe ferments glucose and either lactose or sucrose or both, and makes CO2 and/or H2, carbon dioxide and/or molecular hydrogen

 

This microbe cannot ferment any sugars and does not make hydrogen sulfide

D

D

A

E

B

Catalase test results for 2 microbes, A and B

This microbe is catalase positive

 

This microbe could be a member of the genus Streptococcus

 

This microbe could be a member of the genus Staphylococcus

B

A

B

Which pH indicator: test pair below is incorrect/false?

a. Phenol Red: TSI

b. bromthymol blue: indole

c. methyl red: MR test

d. bromthymol blue: Simmon's citrate test

B

What are the IMViC results for E. coli?

++--

Indole (I): Positive

Methyl Red (M): Positive

Voges-Proskauer (V): Negative

Citrate (C): Negative

Fecal contamination of food and/or drinking water  is indicated by the presence of high numbers of ______.

Candida albicans_

Staphylocoous aureus

 

Enterobacter aerogenes

 

E. coli

E. coli

Bonus True or False?: If a microbe makes urease, it can hydrolyze urea and release ammonia.

True

Bonus True or False: If a microbe is oxidase-negative, you know you can not perform aerobic respiration

False

Bonus, True or False? One way to differentiate Staphylococcus aureus from Staphylococcus epidermidis is that S. aureus is coagulase-positive and S. epidermidis is coagulase-negative.

True