Chapter 18 Review
Staphylococcus
1. Gram + or -? Gram +
2. Can it synthesize catalase? How does this differ Yes, staphylococcus differs from streptococcus
from Streptococcus? because it produces catalase while streptococcus
does not produce catalase.
3. Does it have the tendency to be drug resistant? Yes, it has variety of drug resistance.
Give 2 examples of drugs? 2 examples of the drugs are MRSA and VRSA.
4. Is it part of the normal flora? If so, where? Does Yes, Stap. is a normal flora of nose, skin, gut,
it always cause disease? and vagina. It does not always cause disease.
5. Does salt inhibit its growth? What does this No, salt does not inhibit its growth because it is
make it? haloduric, which means it has tolerant to high
salt concentration.
6. Does it cause nosocomial infections? Yes. For example, S. epidermidis and S. aureus
are normally harmless resident of skin but
associated to serious nosocomial infection (esp.
surgery)
7. What does it mean to be pus forming? Pyogenic
8. Which is the most serious stap. species of the Staphylococcus aureus
pathogens?
S. aureus
9. What areas of the body can be problematic due Skin, GI tract, reproductive (TSS), systemic
to S. aureus? (blood, bone, joint, heart, lung, meninges…)
10. What are 5 examples of exoenzymes utilitzed by 1. Coagulase – trigger blood clotting
Staphylococcus aureus? 2. B-lactamase – break down penicillin and
cephalosporin.
3. Hyaluronidase – break down hyaluronic
acid.
4. Staphylokinase – free bacteria from blood
clots
5. Lipase – hydrolyze fat and lipids in the
host cell membrane
11. What does coagulase trigger? Blood clothing (hide cells from immune cells)
12. What does producing -lactamases enable the Enable the bacterium to break down penicillin
bacterium to do? and cephalosporin, which are antibiotics that
inhibit cell wall production.
13. Is -lactamases commonly produced? Yes, over 90% of strains
, 14. What does hyaluronidase do? What does this Break down hyaluronic acid (hold cells together
allow the bacterium to do? in the connective tissue) that allows the
bacterium to spread.
15. How does the bacterium free itself from clots? Through the staphylokinase. This exoenzyme
dissolve the fibrin threads in blood clots
16. What are some of the toxins produced by S. Hemolysin
aureus? Leukocidin
Exfoliative toxin (A and B)
Enterotoxin
Toxic shock syndrome toxin (TSST)
17. Are these endotoxins or exotoxins? How do you Exotoxins. It is gram positive bacteria, and the
know? toxins target specifically
18. What does leukocidin target? Phospholipid of the cell membrane, and
specifically this cytolytic toxin targets plasma
membrane of the leukocytes (e.g. neutrophil)
and macrophages.
19. What do hemolysis destroy? RBCs
skin
20. Know what folliculitis is. What type of flora Folliculitis is the inflammation of the hair follicles or
causes this? skin gland caused by endogenous flora (or stap.
aureus that already existed in/on the skin)
21. Does folliculitis always stay in the follicle or No, it begins in the follicles or gland but then it can
gland? spread.
22. What are the dangers of untreated boils? Cause tender abscess and pustule or lead to
carbuncle (cluster of boils)
23. What skin infection can also be cause by Impetigo (superficial skin infection starting from
strept and is very contagious and spreads nose or mouth and spread from scratching.
from scratching? Which is more common? It is more common caused by staphylococcus while
only 20% can caused by streptococcus.
24. What does SSSS stand for? Staphylococcal scalded skin syndrome (sloughing off
of the skin)
25. What is required for a strain of aureus to Requires plasmid carried by a strain of S. aureus for
cause SSSS? exfoliative toxin (A&B) to cause SSSS.
26. What is the name of the toxin used to cause Epidermolyic toxin (A&B) or exfoliative toxin (A&B)
SSSS?
27. What occurs to cause this “sloughing off”? Epidermolytic toxin (A&B) cause the separation
between epidermis and dermis by acting on the
desmoglein = sloughing off -> layers of skin become
unstick or peel away
Staphylococcus
1. Gram + or -? Gram +
2. Can it synthesize catalase? How does this differ Yes, staphylococcus differs from streptococcus
from Streptococcus? because it produces catalase while streptococcus
does not produce catalase.
3. Does it have the tendency to be drug resistant? Yes, it has variety of drug resistance.
Give 2 examples of drugs? 2 examples of the drugs are MRSA and VRSA.
4. Is it part of the normal flora? If so, where? Does Yes, Stap. is a normal flora of nose, skin, gut,
it always cause disease? and vagina. It does not always cause disease.
5. Does salt inhibit its growth? What does this No, salt does not inhibit its growth because it is
make it? haloduric, which means it has tolerant to high
salt concentration.
6. Does it cause nosocomial infections? Yes. For example, S. epidermidis and S. aureus
are normally harmless resident of skin but
associated to serious nosocomial infection (esp.
surgery)
7. What does it mean to be pus forming? Pyogenic
8. Which is the most serious stap. species of the Staphylococcus aureus
pathogens?
S. aureus
9. What areas of the body can be problematic due Skin, GI tract, reproductive (TSS), systemic
to S. aureus? (blood, bone, joint, heart, lung, meninges…)
10. What are 5 examples of exoenzymes utilitzed by 1. Coagulase – trigger blood clotting
Staphylococcus aureus? 2. B-lactamase – break down penicillin and
cephalosporin.
3. Hyaluronidase – break down hyaluronic
acid.
4. Staphylokinase – free bacteria from blood
clots
5. Lipase – hydrolyze fat and lipids in the
host cell membrane
11. What does coagulase trigger? Blood clothing (hide cells from immune cells)
12. What does producing -lactamases enable the Enable the bacterium to break down penicillin
bacterium to do? and cephalosporin, which are antibiotics that
inhibit cell wall production.
13. Is -lactamases commonly produced? Yes, over 90% of strains
, 14. What does hyaluronidase do? What does this Break down hyaluronic acid (hold cells together
allow the bacterium to do? in the connective tissue) that allows the
bacterium to spread.
15. How does the bacterium free itself from clots? Through the staphylokinase. This exoenzyme
dissolve the fibrin threads in blood clots
16. What are some of the toxins produced by S. Hemolysin
aureus? Leukocidin
Exfoliative toxin (A and B)
Enterotoxin
Toxic shock syndrome toxin (TSST)
17. Are these endotoxins or exotoxins? How do you Exotoxins. It is gram positive bacteria, and the
know? toxins target specifically
18. What does leukocidin target? Phospholipid of the cell membrane, and
specifically this cytolytic toxin targets plasma
membrane of the leukocytes (e.g. neutrophil)
and macrophages.
19. What do hemolysis destroy? RBCs
skin
20. Know what folliculitis is. What type of flora Folliculitis is the inflammation of the hair follicles or
causes this? skin gland caused by endogenous flora (or stap.
aureus that already existed in/on the skin)
21. Does folliculitis always stay in the follicle or No, it begins in the follicles or gland but then it can
gland? spread.
22. What are the dangers of untreated boils? Cause tender abscess and pustule or lead to
carbuncle (cluster of boils)
23. What skin infection can also be cause by Impetigo (superficial skin infection starting from
strept and is very contagious and spreads nose or mouth and spread from scratching.
from scratching? Which is more common? It is more common caused by staphylococcus while
only 20% can caused by streptococcus.
24. What does SSSS stand for? Staphylococcal scalded skin syndrome (sloughing off
of the skin)
25. What is required for a strain of aureus to Requires plasmid carried by a strain of S. aureus for
cause SSSS? exfoliative toxin (A&B) to cause SSSS.
26. What is the name of the toxin used to cause Epidermolyic toxin (A&B) or exfoliative toxin (A&B)
SSSS?
27. What occurs to cause this “sloughing off”? Epidermolytic toxin (A&B) cause the separation
between epidermis and dermis by acting on the
desmoglein = sloughing off -> layers of skin become
unstick or peel away
