Microbiology and Immunology 2500A/B Lecture Notes - Lecture 18: Staphylococcus, Staphylococcus Lugdunensis, Staphylococcus Epidermidis
21 Mar 2020
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Distinguish species based on coagulase tests (slide or tube) Positive bac produce clumping factors (surface proteins) bind to fibrinogen forms clumps. Skin colonizer (not as dangerous as s. aureus) Main vf: capsule (surface polysaccharide) antibiotic resistance. Attach by protein factors on host surface. Major problem for implanted devices (eg. catheters, prostheses: pseudintermedius (c+) Common colonizer of dogs (+ other mammals) Resistant to multiple antibiotics (eg. methicillin-resistant s. pseudintermedius - mrsp) Transmission to humans can occur but very rare. Efficient colonizer of humans (doesn"t usually cause problems) 30% of global population persistently colonized; 20-30% transiently colonized. Colonization greater infection risk but better prognosis. Generally in skin & mucous membranes (especially anterior nares/nostrils) Fomites inanimate objects that transmit infectious disease directly (eg. towels, razors, bandages) Adhesins (surface protein) allow binding to host proteins colonize. Eg. fibronectin, collagen, and elastin binding proteins. Many strains = many vfs + regulation many diseases. Vf expression regulated based on current needs.
