Micro 3 - Staphylococcus

Question 1

What G(+) has branching filaments and is aerobe and acid fast?

Answer 1

Nocardia.

Question 2

What are 4 G(+) rods?

Answer 2

Clostridium (anaerobe), corynebacterium, Listeria, Bacillus.

Question 3

What G(+) cocci is catalase negative?

Answer 3

Streptococcus.

Question 4

What G(+) cocci are catalase positive?

Answer 4

Staphylococcus.

Question 5

What are 2 G(+) cocci?

Answer 5

Staphylococcus and Streptococcus.

Question 6

What Staphylococcus type is coagulase positive?

Answer 6

S. aureus.

Question 7

What G(+) Staphylococcus are coagulase negative?

Answer 7

S. epidermis and S. saprophyticus.

Question 8

What Staphylococcus is novobiocin sensitive?

Answer 8

S. epidermidis. It is coagulase negative.

Question 9

What Staphylococcus is novobiocin resistant?

Answer 9

S. saprophyticus. It is coagulase negative.

Question 10

How can we differentiate between Staphylococcus vs Streptococcus In a simple microscope finding?

Answer 10

Staphylococcus stick together in clusters and Streptococcus are in chains or in pairs.

Question 11

What does catalase do?

Answer 11

Degrades hydrogen peroxide into oxygen and water. So if you put hydrogen peroxide on a catalase postive bacteria, it will start to make bubbles (oxygen and water).

Question 12

What G(+) Has branching filament that is anaerobe and no acid fast?

Answer 12

Actinomyces.

Question 13

What does coagulase do?

Answer 13

A virulence factor, that allows the bacteria that have it to induce coagulation or blood clotting. It also allows bacterial binding to fibrin and fibrinogen, increasing binding to host tissue and decreasing to phagocytosis.

Question 14

What is the difference between alpha, beta, and gamma hemolysis?

Answer 14

Beta is complete hemolysis, alpha is partial and gamma has no hemolysis.

Question 15

In blood agar, there is a green ring around this cultivated bacteria. Which bacteria could it be?

Answer 15

Green ring around the bacteria is the alpha hemolysis. It can be either S.pneumoniae or viridans streptococci.

Question 16

Which streptococcus have alpha hemolysis?

Answer 16

S.pneumoniae, and viridans streptococci.

Question 17

Which type of stretococcus has beta hemolysis?

Answer 17

S.pyogenes and S.agalactiae.

Question 18

Which type of streptococcus has gamma hemolysis?

Answer 18

Enterococcus.

Question 19

There is bacteria that has alpha hemolysis and has a capsule. Which bacteria is it?

Answer 19

S.pneumoniae.

Question 20

What is another name for Group A streptococcus? What is for Group B?

Answer 20

Group A: S.pyogenes.

Group B: S.agalactiae.

Question 21

What bacteria colonizes the female genital tract and cause pneumonia and meningitis in newborns?

Answer 21

Group B streptococcus (S.agalactiae).

Question 22

Which streptococcus is sensitive to Bacitracin and which one is resistant to it?

Answer 22

S.pyogenes is sensitive to bacitracin while S.agalactiae is resistant.

Question 23

RFF: Acid-fast bacilli on sputum.

Answer 23

Mycobacterium.

Question 24

What does Protein A made from Staphylococcus aureus do?

Answer 24

It binds to human immunogobulin, disrupting opsonization and phagocytosis.

Question 25

What are some pigment-producing bacteria?

Answer 25

Staph aureus (Large golden colonies), Actinomyces israelii (yellow “sulfer” granules), Pseudomonas aeruginosa(blue-green pigment), Serratia marcescens(red pigment).

Question 26

Where do we see staph epidermidis?

Answer 26

It is part of the normal flora. However, when it gets into the blood stream it can colonize prosthetic heart valves, central venous catheters, and prosthetic joints by making a biofilm.

Question 27

Where do we see staph saprophyticus?

Answer 27

UTIs, among young sexually active females.