Staphylococcaceae Flashcards
Staining Reaction and Shape
Gram-positive cocci
Motility
Non-motile
Spore
Non-spore formers
capsule
o encapsulated
o Non-capsulated
O2 requirement
Aerobes/facultative aerobes
NOTABLE BIOCHEMICAL TESTS
CATALASE TEST
NITRATE REDUCTION TEST
TRANSMISSION
Direct contact transmission
HABITAT
Normal colonizers of humans:
o Nasal passages
o Skin
Perianal area
Normal flora; Pathogenic species to man
Attachment to host
MICROCAPSULE
Inhibits opsonization
Binds with Fc of IgC
PROTEIN A
Breakdown of toxic oxygen derivatives
CATALASE
Converts fibrinogen to fibrin
Molecular mimicry
COAGULASE
Forms of COAGULASE
BOUND COAGULASE
FREE COAGULASE
Liquefies purulent materials
Destroys DNA
DNASE
destruction of DNA by DNAse
Decreases viscosity of environment
Facilitates dissemination
Clumping factor
Directly converts fibrinogen to fibrin
BOUND COAGULASE
FREE COAGULASE Reacts with globulin plasma factor to form
staphylothrombin
Neutralizes hyaluronic acid
Spreading factor
Facilitate deep infection
HYALURONIDASE
Digests lipids
Allows bacteria to colonize skin
LIPASE
Acts as fibrinolysin
Allows bacterial dissemination
STAPHYLOKINASE
Cleaves beta-lactam double ring
Plasmid-controlled
mecA gene
BETA-LACTAMASE
Digests lipids
Allows bacteria to colonize skin
LIPASE
Acts as fibrinolysin
Allows bacterial dissemination
STAPHYLOKINASE
Cleaves beta-lactam double ring
Plasmid-controlled
mecA gene
BETA-LACTAMASE
Destroy WBCs
Panton Valentine Leukocidin
LEUKOCIDINS
o Pore-forming toxin
o Important CA-MRSA
Panton Valentine Leukocidin
Lyses RBCS
ALPHA – HEMOLYSIN
ALPHA – HEMOLYSIN includes
Monocytes
Macrophages
Lymphocytes
Dermenocretic
ALPHA – HEMOLYSIN
o Protein exotoxin
BETA – HEMOLYSIN
SPHINGOMYELINASE
o Specific on sphingomyelin
BETA – HEMOLYSIN
SPHINGOMYELINASE
o Membrane disruption
BETA – HEMOLYSIN
SPHINGOMYELINASE
o Cytotoxic to monocytes
BETA – HEMOLYSIN
SPHINGOMYELINASE
o “Hot-cold” hemolysin
BETA – HEMOLYSIN
SPHINGOMYELINASE