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Bakteriologie (Fach) / generell (Lektion)
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- catalase = splits hydrogenperoxide to water and oxygen detectable by putting H2O2 --> if bubbles appear, it's catalase positive
- oxidase = catalyzes oxidation-reduction reactions
- fermentative = can split glycose in absence of oxygen
- coagulase = converts fibrinogen to fibrin --> fibrin may shield staphylococci from phagocygotic cells
- coagulase test 0.5 ml of rabbit blood plasma in tube + 2 drops of overnight culture mix gently, incubation at 37°C if positive, fibrin-clott appears in 2-4 hours
- surface protein A binds to Fc portion of IgG and inhibits phagocytosis
- leukocidin cytolytic destruction of phagocytes
- alpha toxin (hemolysin) spasms of smooth muscle necrotizing, lethal major toxin in gangrenous mastitis
- beta toxin (sphingomyelinase) damages cell membranes
- exfoliative toxin responsible for skin lesions in humans
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- enterotoxins heat stabile toxins associated with staphylococcal food poisoning in human
- toxic shock syndrome toxins induce tissue damage in humans
- extrazellular enzymes which promote tissue invasion lipase esterase elastase staphylo-kinase = fibrinolysin deoxyribonuclease hyaluronidase phospholipase