Bacteria Guide 01 - = major Staph pathogen aureus = gold...

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Staphylococcus aureus= majorStaphpathogenaureus = goldLab IDG+ grape-like clusterscatalase(+)coagulase(+)golden-yellow pigment(from carotenoids)all Staph = cat(+)all Strep = cat(-)S. aureus is onlyStaph that iscoagulase (+)Metabolism- facultative w/ ETCoftenPenicillin GresistantOther UniqueFeatures- thermonstable nucleus (+)- cells divides perpendicular to last plane of division-Ribitolin teichoic acid- high salt tolerance (e.g. can grow on salted meats)-can ferment mannitolorganic acids-longstationary phaseother Staph arethermostable (-)Virulence FactorsProtective-protein A(binds IgGto prevent phago/ops)- coagulase (fibrinformation,αphago)- hemolysins- leukocidins- penicillinaseTissue-destroying- hyaluronidase (breaksdown proteog in CT)- staphylokinase (lysesformed fibrin clots)- lipase (disseminate)-clumping factor (adhere tofibrinogen,αuptake)Host defensemechanismsinclude: skin,group IIAphospholipase A(from platelets),PMN-C3opsonization & Abto toxins-αhemolysin forms pores (most potent), ßlysis- leukocidinPMN lysis + LT4+ IL-8inflamm-Exfoliative exotoxinscalded skin syndrome-Enterotoxin (SE)food poisoning, superAg-TSST-1IL1B +TNFTSS, agr-quorum sensinghemolysins &leukocidin lysecells by creatingpores in themembraneAssociated DiseasesExotoxin-dependent*Gastroenteritis(“food poisoning”)*Toxic Shock Syndrome(can be lethal!)- high fever, nausea & vomiting, watery diarrhea- erythematous rash, HoTN- desquamation of palms & soles (late)*Scalded Skin Syndrome,Bullous Impetigo-Cellulitis, abscess, furuncle, carbuncle, wound inf.Direct Invasion(tend to be localized)* Pneumonia* Meningitis* Osteomyelitis (boys <12)* Acute bacterial endocarditis – rapid veg growth* Bacteremia/sepsis, Septic arthritis – synovial fluid* Skin: folliculitis, carbuncles, abscesses, cellulitis* UTINOT normal flora,but transientlycolonizesnasopharynx of~30% pop.can colonizenasopharynx, skin,vaginarisk in medicalpersonnel,diabetics & IVdrug usersDiagnosis- Culture- PCR detection of ribosomal RNAMRSA!Treatment(s)-penicilinase-resistant penicillins (e.g.Methicillin)-Vancomycinif Methicillin-resistant (MRSA)-Clindamycinno protectiveimmunity; infxncan be aquiredover & overGram stain under microscopeCulture on blood agar
Staphylococcus saprophyticusLab IDG+ grape-like clusterscatalase(+)coagulase(-)all Staph = cat(+)all Strep = cat(-)Metabolism- facultative w/ ETCOther UniqueFeatures- thermostable nucleus (-)- cells divide perpendicular to last place of division-Glycerolin teichoic acid-cannotferment mannitol- “γhemolysis” on blood agarVirulence FactorsAssociated Diseases*UTI- causes 10-20% of 1°UTIs in young- 90% are symptomaticTreatment(s)-Penicillin-Novobiocinresistantcompare S.epidermidisStaphylococcus epidermidisN= nosocomial pathogen & most common isolate of coagulase(-)StaphLab IDG+ grape-like clusterscatalase(+)coagulase(-)all Staph = cat(+)all Strep = cat(-)Metabolism- facultative w/ETCOther UniqueFeatures- thermostable nucleus (-)- cells divide perpendicular to last plane of division-Glycerol

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Term
Spring
Professor
staff
Tags
Bacteria, Escherichia coli, Lab ID

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