Staphylococcus

Question 1

Appearance and shape of staphylococcus

Answer 1

Grape-like appearance; Perfectly spherical

Question 2

Pigment of S. albus/epidermidis

Answer 2

White

Question 3

Pigment of S. aureus

Answer 3

Yellow

Question 4

What are the virulence factors of staphylococcus

Answer 4

1. Surface Proteins
2. Factors inhibiting phagocytosis
3. Protein toxins

Question 5

What are the surface proteins of staphylococcus

Answer 5

1. Laminin and Fibronectin
2. Fibrinogen or Fibrin
3. Collagen-binding factor

Question 6

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

Answer 6

Fibrinogen

Question 7

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

Answer 7

Fibronectin

Question 8

What are the factors that inhibits Phagocytosis

Answer 8

Capsule and Immunoglobulin-binding protein A

Question 9

It is the surface polysaccharide of Serotype 5 or 8

Answer 9

Capsular Polysaccharide

Question 10

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

Answer 10

Microcapsule

Question 11

What is the toxin that acts specifically on polymorphonuclear leukocytes

Answer 11

Leukocidin

Question 12

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

Answer 12

Protein Toxin

Question 13

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

Answer 13

Oligomerize ; Hxamic Rings

Question 14

What blood cells have high affinity to toxins

Answer 14

Human platelets and Monocytes

Question 15

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

Answer 15

A-toxin

Question 16

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

Answer 16

Eicosanoids ; Cytokines

Question 17

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

Answer 17

A-toxin

Question 18

This toxin damages membranes rich in sphingomyelinase C

Answer 18

B-toxin

Question 19

What is the classical test for B-toxin

Answer 19

Lysis of sheep RBC at 4-15 degrees Celsius

Question 20

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

Answer 20

Delta-toxin

Question 21

What toxins are produced separately but acts together to damage membranes

Answer 21

Gamma-toxin and Leucocidin

Question 22

Classification of Enterotoxins and Toxic Shock Syndrome Toxin (TSST1)

Answer 22

Superantigens

Question 23

This superantigen has 6 serotypes that cause diarrhea and vomiting

Answer 23

Enterotoxin

Question 24

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

Answer 24

Toxic Shock Syndrome Toxin 1

Question 25

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

Answer 25

Release of large amount of Cytokines from stimulated T-cells

Question 26

This toxin causes scalded skin syndrome in neonates

Answer 26

Epidermolytic Toxin

Question 27

What are the 2 forms of Epidermolytic/Exfoliative Toxin

Answer 27

ETA and ETB

Question 28

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

Answer 28

Coagulase

Question 29

What is formed coagulase of Staphylococcus binds with prothrombin

Answer 29

Staphylo-thrombin

Question 30

This enzyme is the traditional marker for identifying S. aureus

Answer 30

Coagulase

Question 31

This enzyme from staphylococcus is a known plasminogen activator

Answer 31

Staphylokinase

Question 32

What enzyme is a known Spreading Factor

Answer 32

Hyaluronidase

Question 33

What species of Staphylococcus is coagulase negative

Answer 33

S. epidermidis

Question 34

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

Answer 34

S. epidermidis

Question 35

True or False, S. epidermidis can be cultured in Mannitol Salt Agar (Salt tolerant)

Answer 35

False, it cannot ferment mannitol

Question 36

True or False, S. aureus is Coagulase negative but Catalase positive

Answer 36

False, it is both Coagulase and Catalase positive

Question 37

Diseases caused by S. aureus

Answer 37

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

Question 38

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

Answer 38

S. intermedius

Question 39

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

Answer 39

S. hyicus subsp. hyicus

Question 40

Diagnosis for Staphylococcus diseases

Answer 40

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