Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology 386 > Staph > Flashcards

Staph Flashcards

1
Q

What does staphylococci look like microscopically?

A

Gram +

Cocci

Grape clusters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
  1. What is this organism?
  2. Is it catalase + or - ?
A
  1. Staphylococci
  2. Catalase +
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

List the differences between staphylococcus and micrococcus in the following criteria:

  1. Size
  2. Shape
  3. Gram stain
  4. Colony color
  5. Hemolysis
  6. O2 requirement
  7. Salt tolerance
A
  1. Staphylococcus
    • Small
    • Spherical
    • Gram positive
    • White to golden in color
    • Some hemolytic
    • Facultative O2 requirement
    • Good salt tolerance
  2. Micrococcus
    • Big
    • Not always spherical
    • Decolorizes easily
    • Clear to yellow in color
    • Non - hemolytic
    • Obligate aerobe
    • Poor salt tolerance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are 2 things staphylococci are resistnat to?

A
  1. Heat (except boiling)
  2. Disinfectants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the white, non-hemolytic staphylococci?

A

Staphylococcus epidermidis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is this organism? Which staph species?

A

Staphylococcus aureus

(Notice the gold color of the colonies)

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

What is the natural habitat of Staphylococcus aureus?

A
  1. Skin
  2. Mucous membranes
  3. Oral cavity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

In which 3 types of disease processes can staphylococcus aureus be found?

A
  1. Wound infections
  2. Mastitis
  3. Boils
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  1. Which type of teichoic acid is in S. aureus?
  2. Which type of teichoic acid is in S. epidermidis?
A
  1. Polyribitol
  2. Polyglycerol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Teichoic acid is released from the S. aureus cell and combines with antibodies present. What does this cause?

A

Consumption of complement components up through C5

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

Which species of Staphylococcus have Protein A?

A

S. aureus

S. pseudointermedius

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

What biological effects/functions does Protein A have?

A
  1. Chemotactant
  2. Antiphagocytic
  3. Platelet injury
  4. Anticomplement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Protein A serves as a receptor for what?

A

Fc fragment of immunoglobulin molecules

(Binds antibody via that Fc receptor)

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

What is occuring in the attached image/what is happening?

A

Protein A coats the surface of S. aureus and S. pseudointermedius. It serves as a receptor for the Fc portion of the host’s immunoglobulin molecules. This allows the Staph organism to coat itself in HOST ANTIBODY. By doing so, the bacterium resists chemotaxis, phagocytosis, complement, and causes platelet injury on top of that.

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

The capsule in S. aureus is an important virulence factor to which disease processes?

A
  1. Mastitis in cattle
  2. Bacteremia in humans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the function of lipases?

A

Break down bactericidal fatty acids

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

Staphylococcal hemolysins:

  1. Alpha hemolysin causes ____ hemolysis
  2. Beta hemolysin causes ____ hemolysis
  3. When both are present there is ____ hemolysis
A
  1. Alpha hemolysin = BETA hemolysis
  2. Beta hemolysin = ALPHA hemolysis
  3. Both = DOUBLE ZONE hemolysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

At what point should you check your plates to most accurately observe DZ beta hemolysis?

A

24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Explain the staphylococcal alpha hemolysin.

  1. What is the mechanism of action?
  2. What type of damage does it cause?
A
  1. Through a heptamer, forms transmembrane channels through cell membranes
  2. Causes membrane damage, producing a lot of tissue necrosis
20
Q

Explain the staphylococcal beta hemolysin.

  1. What is the main molecule involved?
  2. What is that molecules activity?
A
  1. Phospholipase-C
  2. Digests cells
21
Q

Which staphylococcal hemolysins produce BETA hemolysis?

A

Alpha hemolysin

Gamma hemolysin

Delta hemolysin

22
Q

Explain the staphylococcal delta hemolysin.

  1. What type of mechanism does it use?
  2. What kinds of damage does this cause?
A
  1. Detergent-like activity
  2. Lethal; dermonecrotic
23
Q

Which staphylococcal hemolysin is pro-inflammatory?

A

Gamma hemolysin

24
Q

Which cells is leukocidin active against?

A

Macrophages

Neutrophils

25
Q

How does Leukocidin work?

Which cells does it affect again?

A

Assembles a ring structure on the cell membrane and creates a pore opening

Affects (1) neutrophils & (2) macrophage

26
Q

Staphylokinase is a fibrinolysin. How does it work?

A

Breaks down the fibrin barrier and allows the spread of the organim

27
Q

What are the 2 coagulase types?

Which is more reliable?

A
  1. Free
    • Release from the cell
    • MORE RELIABLE
  2. Bound
    • Known as clumping factor
28
Q

Staphylocoagulase converts what to what?

A

Fibrinogen to fibrin

29
Q
  1. What is know as the “spreading factor”?
  2. What is it responsible for?
A
  1. Hyaluronidase acid
  2. Responsible for breaking down hyaluronic acid in tissues
30
Q

Nucleases, such as DNase for example, as expecially important to bacteria that stimulate the formation of abscesses.

Why is this?

A

They assist in liquefaction of pus and obtaining of nutrients

31
Q

Explain enterotoxins.

  1. Which enterotoxin is most often associated with disease?
  2. What conditions can all enterotoxins cause?
A
  1. Enterotoxin A
  2. Cause gastrointestinal intoxication resulting in emesis, diarrhea, and enteritis
32
Q

What is responsible for the scalded skin syndrome seen in newborn babies?

A

Exfoliative toxins

33
Q

What are the 3 types of superantigens?

A
  1. Enterotoxins
  2. Toxic shock syndrome toxin-1
  3. Exfoliative toxins
34
Q

This is gangrenous mastitis in a cow.

  1. What bacterial genus and species is responsible for this infection?
  2. Which type of superantigen is involved?
A
  1. Staphylococcus aureus
  2. TSST-1
35
Q

How might S. aureus affect a dog?

A
  1. Skin infections
  2. Pustular dermatitis
  3. Wounds
  4. Ear
  5. Urogenital (cystitis)
  6. Acral lick dermatitis
36
Q

How might S. aureus affect a cat?

A
  1. Wounds
  2. Abscesses
  3. Urinary tract infections
37
Q

How might S. aureus affect a horse?

A
  1. Wounds
  2. Abscesses

Although more likely to be S. pseudointermedius

38
Q

How might S. aureus affect a chicken or turkey?

A
  1. Foot swellings (bumblefoot)
  2. Ocular infections
39
Q

How might S. schleiferi affect a dog?

A

Pyoderma

Otitis externa

40
Q

Is Staphylococcus epidermidis coagulase - or + ?

A

Coagulase NEGATIVE

41
Q

Which organism is responsible for the majority of mastitis seen in dairy cattle?

A

Staphylococcus epidermidis

42
Q

This is biofilm growth from an intravenous catheter.

What is the organism?

A

Staphylococcus epidermidis

43
Q

What is the cause of greasy pig disease?

44
Q

What kinds of problems can S. hyicus subspecies 1 cause in pigs?

A

Greasy pig disease

Septicemia polyarthritis

Microbiology 386 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions