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1

Are Staphylococcus normal flora

yes, but they can be opportunistic pathogens

2

What are the nine groups of Gram positive pathogens we study

1. Staphylococcus Aureus
2. Streptococcus Pyogenes (A)
3. Streptococcus pneumoniae
4. Bacillus Anthracis
5. Clostridium (perfringins, dificile, tetani, and botulinum)
6. Listeria monocytogenes
7. Corynebacterium diptheriae
8. propionibacterium acnes
9. Actinomyces species

3

Staphylococcus is motile or nonmotile?

non-motile

4

how does Staphylococcus interact with oxygen (anarobe, aerobe)

facultative aerobe

5

What does Staphylococcus look like under a microscope

cocci in irregular clusters (grapes)

6

What is the most common organism found on the skin

Staphylococcus epidermis

7

Where is Staphylococcus aureus typically carried in 30-50% of the healthy population

nose and perineum

8

How can you tell between Staphylococcus aureus and Staphylococcus epidermis

Staphylococcus Areus is
coagulase positive, mannitol positive
Staphylococcus Epidermis
coagulase negative, mannitol negative

9

which is more virulent Staphylococcus Aureus or Staphylococcus epidermis

Staphylococcus Aureus

10

How many bacteria are required for disease to result from a staph infection

only a few hundred bacteria

11

what are the three things about Staphylococcus that cause pathogenicity

1. It's ability to evade phagocytosis
2. Production of enzymes
3. production of toxins

12

What are the three categories of Staphylococcus diseases

Noninvasive disease
Cutaneous disease
Systemic disease

13

What is a non-invasive Staphylococcus disease

food poisoning that results from ingested food contaminated with enterotoxin

14

What are examples of cutaneous Staphylococcus disease

scalded skin syndrome
impetigo
folliculitis
furuncles

15

How does Staphylococcus defend itself against phagocytosis

Protein A
Bound Coagulase:

16

how does Protein A help Staphylococcus defend against phagocytosis

Protein A onthe bacterial surface binds antibodies by the Fc end. This inhibits opsonization and complement

17

how does bound coagulase help Staphylococcus defend against phagocytosis

converts blood protein fibrinogen into fibrin molecules, which make blood clots, the Staphylococcus hides from the phagocytes in the clots

18

What are the 5 enzymes created by Staphylococcus that attribute to its virulence

Cell-free coagulase
hyaluronidase
staphylokinase
lipases
B-lactamase

19

What does Cell-free coagulase do for Staphylococcus

triggers fibrin formation, which helps the Staphylococcus hide from phagocytes

20

What does hyaluronidase do for Staphylococcus

breaks down hyaluronic acid, which allows the bacteria to spread between cells

21

what does staphylokinase do for Staphylococcus

dissolves fibrin threads in blood clots, which allows Staphylococcus aureus to free itself from clots

22

what do lipases do for Staphylococcus

digests lipids, allows Staphylococcus to grow on the skins surface and in oil glands

23

what do B-lactamases do for Staphylococcus

Breaks down penicilins, makes them resistant to beta-lactams

24

What are the 4 toxins produced by Staphylococcus

Cytolytic toxins
exfoliative toxins
Toxic shock syndrome toxins
Enterotoxins

25

What are the two cytolytic toxins created by Staphylococcus and what do they do

alpha-toxins- pore forming toxins
PVL - beta pore forming toxin that lyses leukocytes

26

What do the exfoliative toxins of Staphylococcus cause

they cause the patients skin cells to separate from each other and slough off the body

27

What does the toxic shock syndrome toxin of Staphylococcus cause

it causes toxic shock syndrome, which is caused by the creation of a superantigen

28

What do enterotoxins of Staphylococcus cause

they stimulate intestinal muscle crampings, naseua, and intense vomiting (staph food poisoning)

29

Does Staphylococcus aureus cause food poisoning

yes

30

Does Staphylococcus cause colitis

yes