Staphylococcus

Question 1

Staphylococcus

Answer 1

2. Virulence: produce coagulases (coagulate the fibrinogen in blood, protecting bact. from phagocytosis)
   - - Some are virulent due to capsules
3. Exotoxin

Question 2

Staphylococcus aureus

Answer 2

1. Enterotoxin (a kind of exotoxin): affects the intestines in the same way as cholera toxin; is also associated with toxic shock syndrome
2. Scalded skin syndrome
3. Food poisoning

Question 3

Staphylococcus aureus

Answer 3

1. Skin infections:
   a. Impetigo -
   b. Folliculitis
   c. Toxic shock syndrome

Question 4

Staphylococcus epidermidies

Answer 4

1. Coagulase-negative strains
2. Very common on the skin, representing 90% of the normal microbiota
3. Opportunistic; pathogenic only when skin barrier is broken

Question 5

Staphylococcus aureus

Answer 5

Most pathogenic of the staphylococci; almost ALL pathogenic strains of S. aureus are coagulase positive
a. Coagulase: convert fibrinogen to fibrin, which protects the bacteria from phagocytosis

Question 6

Folliculitis, sty, furuncle, abscess

Answer 6

1. S. aureus infection of hair follicles
   The infected follicle of an eyelash is called a sty
2. A more serious hair follicle infection is the furancle (boil)

Question 7

Streptococcus pyogenes. toxins (move to another flash card!

Answer 7

1. Streptokinases: dissolve blood clots
2. Hyaluronidase: dissolves hyaluronic acid
3. Deoxyribonucleases: degrades DNA
4. Leukocidins: destroys leukocytes
5. Erythrogenic toxins: responsible for the red rash and other symptoms of Scarlet Fever