Staph Flashcards
All staph are Aerobic or facultative anaerobic except for
S. saccharolyticus
lipochrome fat soluble pigment that is responsible for the
golden pigment production of S. aureus
Staphyloxanthin
acts as a virulence factor that provides antioxidant
properties to staph
Staphyloxanthin
Associated with UTIs in young women
Staphylococcus saprophyticus
This species adheres more effectively to the epithelial cells
lining the urogenital tract than other CoNS
S.saphro
Rarely found on other mucous membranes or skin surfaces
S.saphro
Infections are predominantly hospital-acquired
S.epi
Can cause health-care acquired UTIs and prosthetic valve
endocarditis
S.epi
Biofilm productions: key component to its pathogenesis
o biofilm – communities of bacteria that has enclosed
themselves to produce extracellular matrix
S.epi
• Has a positive clumping factor test result, but it has a negative
tube coagulase reaction
S.lugdu
Can cause both community-associated and hospital-acquired
infections
S.lugdu
Known to contain the mecA gene
S.lugdu
Can cause an aggressive type of endocarditis
S.lugdu
particular gene that codes for methicillin resistance of most
microorganisms
S.lugdu
Selective media for s.aureus
7.5% NaCl MSA
▪ S. aureus can ferment mannitol
Selective and Differential Media of S.aureus
CHROMagar
Staphylococci
ferments glucose while micrococcus fails to produce acid under
anaerobic conditions
Oxidation-Fermentation (O/F) Reaction
most rapid method for separating staphylococci from
other gram-positive cocci
Modified Oxidase Test
best test for pathogenic S. aureus
Coagulase Test
reagent for coagulase test
Rabbit plasma
: used to differentiate
S. aureus (negative) from S. lugdunensis, S. intermedius and S.
schleiferi (positive)
Pyrrolidonyl arylamidase (PYR) activity
: used to differentiate S. aureus
(positive – red formation on top of media) from S. intermedius
(negative)
Vogue-Proskauer (VP) test:
Used to differentiate S.saphro and S.epidermidis
Novobiocin (5-ug) Susceptibility Testing
