Microbiology lab final
Microbiology
Final exam
Study reference
1. Gram Stain
* Verify if bacteria are present or not.
* Controls – positive (purple) – S.aureus
negative ( red/pink) – E.coli
2. Endospore Stain
Positive controller – B. magneterium
Green spore- Positive
Pink (vegetative ) – Negative
3. Acid fast
Positive control – M. smeagmatis
Blue – negative
Pink /red- positive
4. Motility
Positive control - P.vulgaris
A. Non motile is negative test
B. Motile is a positive test
5. Carbohydrates fermentation (test for gram -)
( glucose , manitol, lactose)
Positive control – E.coli (yellow)
Red- no color change – negative test
Yellow – color change – positive test
6. MaConkey’s Agar
Positive control - E.coli
Selective for negative gram stain . Differential for organism that could ferment lactase
Growth pink – positive
No growth – negative
7. Gelatin Hydrolysis ( Gelatinase)
Positive control – P.aeruginosa
Liquid –positive test
Solid - Negative test
8. Blood agar
Positive control – S. aureus
A. Betahemolysis
B. alphahemolysis
C. gammahemolysis
9. FTM
*broth – O2 relationship with
10. MRVP (mix acid fermentation)
MR- methyl red (PH lower than 4.4)
Positive control – E.coli red color- positive test no red – negative test
11. Voges Proskauer ( acetone) –precursor for those who fermented butane
Positive control- E. aerogenosa Red color – positive test No color change – negative test
12. Nitrate Reduction
Enzyme – nitrate redactase
Positive control- E.coli
Pink color- positive
No pink – negative
13. Starch hydrolysis (iodine), test for enzyme laminase
Positive control- B. subtillus Zone of clearing- positive test
No zone of clearing – negative test
14. Fat hydrolysis, test for enzyme lipase
Positive control – S.aureus
Dark blue – positive test
No dark blue- negative test
15. Casein Hydrolysis, enzyme caseinase
Positive control – B. subtilus
Positive- zone of clearing
Negative – no zone of clearing
16 Indole Production
Final exam
Study reference
1. Gram Stain
* Verify if bacteria are present or not.
* Controls – positive (purple) – S.aureus
negative ( red/pink) – E.coli
2. Endospore Stain
Positive controller – B. magneterium
Green spore- Positive
Pink (vegetative ) – Negative
3. Acid fast
Positive control – M. smeagmatis
Blue – negative
Pink /red- positive
4. Motility
Positive control - P.vulgaris
A. Non motile is negative test
B. Motile is a positive test
5. Carbohydrates fermentation (test for gram -)
( glucose , manitol, lactose)
Positive control – E.coli (yellow)
Red- no color change – negative test
Yellow – color change – positive test
6. MaConkey’s Agar
Positive control - E.coli
Selective for negative gram stain . Differential for organism that could ferment lactase
Growth pink – positive
No growth – negative
7. Gelatin Hydrolysis ( Gelatinase)
Positive control – P.aeruginosa
Liquid –positive test
Solid - Negative test
8. Blood agar
Positive control – S. aureus
A. Betahemolysis
B. alphahemolysis
C. gammahemolysis
9. FTM
*broth – O2 relationship with
10. MRVP (mix acid fermentation)
MR- methyl red (PH lower than 4.4)
Positive control – E.coli red color- positive test no red – negative test
11. Voges Proskauer ( acetone) –precursor for those who fermented butane
Positive control- E. aerogenosa Red color – positive test No color change – negative test
12. Nitrate Reduction
Enzyme – nitrate redactase
Positive control- E.coli
Pink color- positive
No pink – negative
13. Starch hydrolysis (iodine), test for enzyme laminase
Positive control- B. subtillus Zone of clearing- positive test
No zone of clearing – negative test
14. Fat hydrolysis, test for enzyme lipase
Positive control – S.aureus
Dark blue – positive test
No dark blue- negative test
15. Casein Hydrolysis, enzyme caseinase
Positive control – B. subtilus
Positive- zone of clearing
Negative – no zone of clearing
16 Indole Production