Lecture 10 - Staphylococcus Flashcards
Is staph gram + or -?
Positive
What type of arrangements does staph make?
Irregular
What the Catalase result for Staph?
Positive
What color are Staph colonies?
White to golden
What is the oxygen preference of MOST staph bacteria?
Facultative anerobes
What is the general characteristics of Staph?
Commensal, found on skin and mucous membranes
Opportunistics pathogens - pyogenic infectiosn
What color is S. Aureus on cows and humans?
Golden
How are the two different groups of Staph separated?
Coagulase + and -
What does coagulase correlate with?
Pathogenicity
What are the two methods for a coagulase test?
Test tube + Microscope slide
What is used in the coagulase test?
Rabbit plasma
What is the test tube coagulase test showing
Secreted enzyme
What is the microscope slide coagulase test showing?
Clumping factors
What are your CoPS staphs?
Aureus spp. Aureus
Pseudintermedius
Hyicus
What are your CoNS staphs?
Xylosus + Sciuri
What are the major pathogenic staphs?
Aureus + Hyicus + SIG
What are the three staphs within SIG?
Intermedius + Pseudintermedius + Delphini
What does it mean to be a major pathogenic staph?
Major cause of Mastitis
What are the main virulence factors on the surface of Staph?
Protein A + MSCRAMMS
What does Protein A in staph do?
Bings IgG by FC
What are MSCRAMMS?
Fibronectin + Collagen binding proteins
What two exoenzymes does staph have?
Coagulase + Urease
What does urease do?
Raises pH of urine
What happens symptomatically with urease?
Struvite crystals can form in kidneys and ureters
What are struvite crystals made out of?
Ammonium magnesium phosphate
What are the types of exotoxins found in staph?
Enterotoxins + TSST-1
What does urease do chemically?
Hydrolyze urea to ammonia + CO2
What are enterotoxins responsible for?
Diarrhea + Vomiting
What does S. aureus enterotoxin normally affect?
Goats, cattle, and sheep
What does S. pseudintermedius normally effect?
Dogs SEC
What type of activity does SE and TSST-1 might have?
Superantigen activity
What bacteria has urease?
S. Pseudintermedius
What are the two types of epidermolytic toxins?
Exforliative + Exforlative-like
What bacteria has Exfoliative toxins?
S. Aureus
What is the effect of the epidermolytic toxin in S. Aurues?
Bullous impetigo + scalded skin syndrome
Digests epidermal intercellular connections
What bacteria have exfoliative-like toxins?
S. hycius + S. pseudointermedius
What does the exfoliative-like toxin in S. hycius do?
Exudative epidermitis in pigs
What are hemolysins?
Membrane damaging toxins
What do hemolysins damage?
RBC + Platlets + Monocytes + LEU + Lipid membranes
What are the four types of hemolysins?
Alpha + Beta + Gamma + Delta
What do alpha toxins do?
Complete lysis - beta-hemolysis