GRAM POSITIVE COCCI; CATALASE POSITIVE Flashcards
(22 cards)
Identify:
Identify: (2)
Gram (+) Cocci; Catalase (+)
- Staphylococci
- Microccoci
What is the positive test for catalase test?
Bubbling/Effervesence
Reagent used for catalase test for gram positive cocci:
3% Hydrogen Peroxide (H2O2)
Gram positive cocci with tetrad/cuboidal packets morphology:
Micrococci
Gram positive cocci with grape-like clusters morphology:
Staphylococci
Enumerate significant species in genus Staphylococci: (6)
- S. aureus
- S. epidermidis
- S. saprophyticus
- S. lugdunensis
- S. intermedius
Species in genus Staphylococci that are coagulase negative: (2)
- S. epidermidis
- S. saprophyticus
They are termed as CoNS or Coagulase Negative Staphylococci
Coagulase variable Staphylococci: (2)
- S. lugdunensis
- S. intermedius
Important identification tests for S. aureus: (3)
- Coagulase test
- Mannitol Fermentation test
- DNase test/Thermonuclease test
Which type of coagulase does slide method detect?
Bound coagulase/clumping factor
Which type of coagulase does tube method detect?
Free coagulase
Requirement for tube method in coagulase test:
Incubation at 37degC
Reagent for coagulase test:
Rabbit’s plasma collected using EDTA
What is the test result if citrated plasma was used in coagulase test?
False positive (+)
Positive result for coagulase test:
Clot formation
What does Mannitol Fermentation test detect?
Acid production
Reagent and media for Mannitol Fermentation test: (3)
- Mannitol Salt agar
- 7.5% Salt
- Phenol red
What is the inhibitor of Mannitol Fermentation test:
7.5% salt
What is the indicator of Mannitol Fermentation test:
Phenol red
Positive result for Mannitol Fermentation Test:
Yellow halo around the colonies
This is the only species that grows in MSA:
S. aureus
