Staphylococcus Flashcards

Module 1

1
Q

Appearance and shape of staphylococcus

A

Grape-like appearance; Perfectly spherical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Pigment of S. albus/epidermidis

A

White

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Pigment of S. aureus

A

Yellow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the virulence factors of staphylococcus

A
  1. Surface Proteins
  2. Factors inhibiting phagocytosis
  3. Protein toxins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the surface proteins of staphylococcus

A
  1. Laminin and Fibronectin
  2. Fibrinogen or Fibrin
  3. Collagen-binding factor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What substance is the dominant component that leads to adherence of S. aureus

A

Fibrinogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the predominant ligand that promotes attachment after degradation of Fibrinogen

A

Fibronectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the factors that inhibits Phagocytosis

A

Capsule and Immunoglobulin-binding protein A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

It is the surface polysaccharide of Serotype 5 or 8

A

Capsular Polysaccharide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is capsular polysaccharide called because it can only be visualized on electron microscopy after antibody labelling

A

Microcapsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the toxin that acts specifically on polymorphonuclear leukocytes

A

Leukocidin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

These are virulence factors that are responsible for symptom conditions during infections; are also known to be membrane damaging toxin

A

Protein Toxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A toxin binds to membranes of susceptible cells and its subunits _____________ to form __________________

A

Oligomerize ; Hxamic Rings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What blood cells have high affinity to toxins

A

Human platelets and Monocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What toxin binds to host cell and its subunits oligomerize to form hexamic rings

A

A-toxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

These is released from the series of secondary reactions that triggers production of inflammatory mediators producing symptoms of septic shock

A

Eicosanoids ; Cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What toxin is known to be the most potent membrane-damaging toxin and is the major virulent factor

A

A-toxin

18
Q

This toxin damages membranes rich in sphingomyelinase C

A

B-toxin

19
Q

What is the classical test for B-toxin

A

Lysis of sheep RBC at 4-15 degrees Celsius

20
Q

This toxin is a small peptide toxin produced by most strains of S. aureus phospholipase

A

Delta-toxin

21
Q

What toxins are produced separately but acts together to damage membranes

A

Gamma-toxin and Leucocidin

22
Q

Classification of Enterotoxins and Toxic Shock Syndrome Toxin (TSST1)

A

Superantigens

23
Q

This superantigen has 6 serotypes that cause diarrhea and vomiting

A

Enterotoxin

24
Q

This superantigen is responsible for 75% of Toxic Shock Syndrome including menstrual cases

A

Toxic Shock Syndrome Toxin 1

25
Q

What is another factor that causes the symptoms of Toxic Shock Syndrome

A

Release of large amount of Cytokines from stimulated T-cells

26
Q

This toxin causes scalded skin syndrome in neonates

A

Epidermolytic Toxin

27
Q

What are the 2 forms of Epidermolytic/Exfoliative Toxin

A

ETA and ETB

28
Q

This extracellular protein binds to prothrombin in host to form Staphylo-thrombin that activates protease

A

Coagulase

29
Q

What is formed coagulase of Staphylococcus binds with prothrombin

A

Staphylo-thrombin

30
Q

This enzyme is the traditional marker for identifying S. aureus

A

Coagulase

31
Q

This enzyme from staphylococcus is a known plasminogen activator

A

Staphylokinase

32
Q

What enzyme is a known Spreading Factor

A

Hyaluronidase

33
Q

What species of Staphylococcus is coagulase negative

A

S. epidermidis

34
Q

This species of Staphylococcus is the main cause of infection associated with prosthetic devices

A

S. epidermidis

35
Q

True or False,

S. epidermidis can be cultured in Mannitol Salt Agar (Salt tolerant)

A

False, it cannot ferment mannitol

36
Q

True or False,

S. aureus is Coagulase negative but Catalase positive

A

False, it is both Coagulase and Catalase positive

37
Q

Diseases caused by S. aureus

A
  1. Botryomycosis
  2. Mastitis
  3. Tick Pyemia
  4. Periorbital Eczema in sheep
  5. Purulent Synovitis
  6. Cutaneous Staphylococcosis
  7. Porcine Necrotizing Staphylococcal Endometritis
38
Q

What species of Staphylococcus is most prevalent in dogs and other carnivores

A

S. intermedius

39
Q

This species of Staphylococcus enters through breaks in skin and is an exudative epidermitis of swine

A

S. hyicus subsp. hyicus

40
Q

Diagnosis for Staphylococcus diseases

A
  1. Smear
  2. Culture on Blood Agar Plate
  3. Mannitol Salt Agar
  4. Coagulase
  5. Deoxyribonuclease