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Bakteriologie (Subject) / Cocci (Lesson)
Staphyloccocus, Streptococcus, Micrococcus, Lactobacillus
This lesson was created by eysnirmgard.
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- Staphylococcus Morphology no flagella --> non-motile no capsule coccus shaped, in irregular clusters do not form spores gram+
- Staphylococcus Culture non fastidious --> nutrient agar, 37°C, 1 day facultative anaerobs (exc. S. aureus ssp. anaerobius) colony morphology: opaque, human and bovine strains produce golden pigments --> S. aureus ssp. anaerobius no pigment production broth: uniform turbidity
- Staphylococcus selective culture 10% NaCl + mannitol + phenolred agar --> red colonies Na-tellurite + glycine + pyruvic acid + eggyolk --> black colonies blood agar + nalidixic acid + colistin --> inhibit gram- bacteria
- Staphylococcus biochemistry catalase + oxidase - fermentative
- Staphylococcus Resistance survive for months in dry environment 60°C for 30 minutes 3% formalin for 30 minutes
- mrsa = methicillin resistant staphylococcus aureus strain --> resistant against: betalactam antibiotics --> multiresistant against: clindamycin, aminoglycosides, fluoroquinolons
- coagulase positive staphylococcus species S. aureus ssp. aureus S. aureus ssp. anaerobius S. pseudointermedius
- coagulase negative staphyloccus species S. hyicus S. epidermidis S. haemolyticu S. gallinarium S. equorum S. felis
- S. aureus ssp. aureus diseases local suppuration abscesses infections following surgeries
- S. aureus ssp. aureus in poultry arthritis septicaemia in 2-5 week old turkey
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- S. aureus ssp. aureus in cattle mastitis udder impetigo
- S. aureus sip. aureus in pigs mastitis metritis udder impetigo
- S. aureus ssp. aureus in sheep mastitis dermatitis septicaemia in 2-5 weeks old lamb
- S. aureus ssp. aureus in goat mastitis
- S. aureus ssp. aureus in horses mastitis botrymycosis (in spermatic cord after castration)
- S. aureus ssp. aureus in rabbits dermatitis septicaemia in 2-5 weeks old rabbit
- S. aureus ssp. anaerobes diseases morel-disease in sheep (caseous lymphadenitis)
- S. pseudointermedius diseases dog, cat: pyoderma pyometra otitis externa mastitis endometritis cystitis osteomyelitis wound infections
- S. hyicus diseases greasy pig disease (exudative dermatitis) under 3 months of age
- S. epidermidis diseases local suppuration dermatitis
- S. haemolyticus diseases local suppuration dermatitis
- S. gallinarium diseases local suppuration dermatitis
- S. felis diseases local suppuration dermatitis
- virulence factors of staphylococci coagulase lipase esterase elastase staphylo-kinase deoxyribonuclease hyaluronidase phospholipase leukocidin alpha toxin (haemolysin) beta toxin (sphingomyelinase) exfoliative toxin enterotoxins toxic shock syndrome toxins
- Streptococcus habitat distributed worldwide skin, mucous membranes (upper respiratory tract, lower genital, digestive tract) food milk
- streptococcus morphology no spores coccus chain formation capsule in S. pyogenes, S. pneumoniae, S. equi no flagella --> non motile fimbria in S. pyogenes, S. salivarius, S. sanguinis cell wall M proteins in S. pyogenes, S. equi, S. porcinus
- Streptococcus Resistance good, survive for weeks in dark and wet environment susceptible to dessication
- Streptococcus Culture more fastidious --> enriched media (blood or serum) facultative anaerobes, co2 enhanced growth incubation: aerobically, 37°C, 24-48 h small translucent colonies haemolytic: - alpha: partial or incomplete = greenish-hazy zones - beta: complete = clear zones - gamma: no haemolysis
- Streptococcus Selective Cultures Edwards agar: crystal violet + thallium-so4 + esculin + blood !! no growth on MacConkey agar!!
- streptococcus biochemistry catalase - oxidase - fermentative
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- streptococcus virulence factors extracellular enzymes and toxins: - streptolysins (haemolysins) - fibrinolysins - hyaluronidase - DNase - NADase - streptokinase - proteases
- Streptococci antigens - cell wall polysaccharide --> lancefield grouping (A-W) - capsule antigens in: S. pyogenes, S. suis, S. pneumoniae, S. equi
- lance field group A S. pyogenes
- Lancefield grouping B S. agalactieae
- lance field grouping C S. dysgalactiae ssp. dysgalactiae S. dysgalactiae ssp. equisimillis S. equi ssp. equi S. equi ssp. zooepidemicus
- lance field grouping D E. faecalis E. faecium S. bovis S. equinus
- lance field grouping E S. uberis
- lancefield grouping S S. suis
- streptococcus pathogenicity - local suppuration (pyogenic infections) - metritis, mastitis, arthritis, meningitis - septicaemia - strangles of horses - pneumonia
- S. pyogenes diseases scarlet fever (erythrogen-toxin producing strains) rheumatic fever glomerulonephritis pharyngitis tonsilits human erysipelas impetigo
- S. agalacticae diseases mastitis
- S. dysgalacticae diseases mastitis
- S. uberis diseases mastitis
- S. dysgalacticae ssp. equisimilis diseases lymphadenitis abortion
- S. equi ssp. equi diseases strangles of horses
- S. equi ssp. zooepidemicus diseases suppuration septicaemia (human) mastitis
- S. suis diseases septicaemia arthritis meningitis
- S. porcinus diseases lymphadenitis abscesses
- S. canis diseases metritis septicaemia
- oral streptococci S. salivarius S. sanguinis S. mutans