Lab Exam #2 Review Flashcards
Which tests should be used for G+ rods? (1)
LM (litmus milk)
Which tests should be used for G+ cocci? (5)
1) BA
2) MSA
3) Coagulase (SA+; SE-)
4) SM-110
5) MS
Which tests should be used for G- rods (6)?
1) SS
2) MAC
3) TSI
4) Citrate (EC-; EA+)
5) VP (EC-; EA+)
6) Methyl Red (EC+; EA+)
Which tests should be used for G- cocci? (1)
1) SIM
Which tests should be used for G- bacteria in general? (1)
EMB
Which tests are differential only? (6)
1) LM
2) TSI
3) Citrate
4) VP
5) MR
6) SIM
Which tests are selective only? (2)
Coagulase and BA
Which tests are both selective and differential? (6)
1) SS
2) SM-110
3) MAC
4) MSA
5) MS
6) EMB
List the enzymes the following tests look for the presence of, and state what each enzyme degrades:
1) DNase
2) Urea
3) Nutrient starch
4) LYS
5) Nutrient gelatin
6) Catalase
7) PHE
8) ONPG
9) Coagulase
10) MS
1) DNase: DNase, DNA
2) Urea: Urease, urea
3) Nutrient starch: Amylase, starch
4) LYS: Lysine decarboxylase, amino acid
5) Nutrient gelatin: Gelatinase, gelatin
6) Catalase: Catalase, H2O2
7) PHE: Phenylalanine deaminase, phenylalanine
8) ONPG: B-galactosidase; lactose fermentation
9) Coagulase: Coagulase, protein clotting
10) MS: Saccharase; sucrose
What question does a NO3 (nitrate) test answer?
Does bacteria use NO3- as a terminal electron acceptor in anaerobic respiration (and denitrify it to N2)?
1) What does a SIM test test for? (3 things)
2) What does an EMB test test for? (2 things)
1) SIM: Motility and H2S to FeS production (some G- cocci); indole production (from tryptophan breakdown) (EC+; EA-)
2) EMB: Ability to grow on EMB (G-) and coliform differentiation (by color and lactose fermentation)
1) What does an SM-110 test test for? (3 things) What bacteria are positive?
2) What does an MS test test for? What bacteria are positive?
1) Ability to grow on NaCl (G+); gelatinase presence; glycolysis of fructose-phosphate from mannitol (G+ cocci: SA+; SE-)
2) Ability to grow on MS’s sucrose due to saccharase (G+ cocci: SM and EF+)
What do the following tests look for?
1) Methyl red
2) VP
3) Citrate
1) Ability to ferment (make) mixed acids, decreasing pH (EC+, EA-)
2) Ability to ferment alcohol, creating intermediate acetylmethylcarbinol (EC-; EA+)
3) Ability to grow on citrate which releases ammonia, increasing pH (EC-; EA+)
What does a TSI test look for? (3 things)
Include the color of each thing
1) Ability to ferment glucose (red over yellow, K/A)
2) Ability to ferment lactose and/or sucrose (all yellow, A/A)
3) H2S production (black)
What does an MAC test look for? (2 things)
Include what species are positive for each thing.
1) Ability to grow on MAC (G-)
2) Ability to ferment lactose (EC+, red)
What does an SS test look for? (3 things).
Include what species are positive for each thing.
1) Ability to grow on SS (G- non-coliform rods)
2) Ability to ferment lactose (EC+, red)
3) H2S production (Salmonella+)
What does an MSA test look for? (2 things)
Include what species are positive for each thing.
1) Ability to grow on MSA (G+ cocci: Bacillus and staphylococcus)
2) Ability to ferment mannitol (SA+)
1) What genuses are a BA test differential for?
2) What question does a BA test answer?
Include which species are positive.
1) Staph and strep
2) Does bacteria do gamma, alpha, or beta hemolysis? (G+ cocci: SA does beta; SE does gamma)
What 2 things does a LM test look for? Include what species is positive.
1) Ability to ferment lactose and produce acid, decreasing pH (Bacillus)
2) Ability to break down casein protein in milk
1) What 2 tests use neutral red indicator?
2) What color is neutral red indicator when introduced to an acid?
1) SS and MAC
2) Red: acidic
1) What 3 tests use phenol red indicator?
2) What color is phenol red when introduced to an acid?
1) MSA, TSI, Urea
2) Yellow: acidic
1) What test uses litmus milk as an indicator? What color is it when positive?
2) What test uses methyl green as an indicator? What color is it when positive?
3) What test uses bromcresol purple as an indicator?
4) What test uses bromothymol blue as an indicator?
1) LM: litmus milk (white: acidic = +)
2) DNase: methyl green (clearing = +)
3) LYS: bromocresol purple (purple/black: basic = +)
4) Citrate: bromothymol blue (vivid blue: basic = +)
Which 4 tests can help differentiate between Staphylococcus aureus (SA) and Staphylococcus epidermidis (SE)?
Report when each is positive and negative
1) Coagulase (TSB): SA+; SE-
2) BA: SA beta; SE gamma
3) MSA: SA+; SE-
4) SM-110: SA+; SE-
Salmonella and shigella grow well on which two media?
MAC and SS
1) What two bacterial species ferment mannitol (MSA test)? What color does this result in?
2) What two bacterial species do not ferment on MSA? What color does this result in?
1) S. aureus (SA) and B. subtilis (BS): turn yellow (acidic)
2) S. epidermidis (SE) and B. cereus (BS): stay red (basic)
What 7 media can help differentiate between E. coli (EC) and E. aerogenes?
1) VP: EC-; EA+
2) Citrate: EC-; EA+
3) Indole: EC+; EA-
4) Methyl red: EC+; EA-
5) MAC: EC+; EA-
6) SS: EC+; EA-
7) SIM: EC+; EA-
List the 3 media that use phenol red and what color they are when positive
1) MSA: Turns yellow when positive
2) TSI: Red is ‘k’, yellow is ‘a’
3) Urea: Turns red when positive
