MLT 140 Quiz 2

What is an enzyme that makes organism resistant to penicillin class of drugs?

Beta-Lactamase

What is an protein-toxin associated with food poisoning?

Enterotoxin

What damages RBC, platelets and WBC and macrophages?

Hemolysin

What is the clotting enzyme used for differentiating Staph. spp.?

Coagulase

What is the spreading factor enzyme that destroys connective tissue?

Hyaluronidase

What differentiates Staph from Streps?

Catalase

What is the epidermolytic toxin associated with ritters disease?

Exfoliative toxin

What causes chemical decomposition of dsDNA?

DNAse

What is two disease caused by Staph aureus?

TSS and Food poisoning

What is the gene associated the antibiotic resistance demonstrated in MRSA?

meca

What is the reagent for the tube coagulase test?

Rabbit Plasma

What is the organism that is the negative control for the slide coagulase test?

Epidermidis

If the organism shows beta hemolysis on the BAP, is a gram positive coccus on the gram stain and is catalase positive, what is the next test that should be performed?

Coagulase

What is the organism that is the positive control for MSA?

S. aureus

What is the type of culture from which S. saprophyticus is usually recovered?

Urine

What is called when you see a red/clear colony on MSA indicates what organism?

Coagulase, Negative Staph

How does Staphylococcus appear on MAC?

It will not grow because MAC is selective

What is in the MSA that makes it a selective agar?

Salt

What is the type of species of Staphylococcus which causes TSS?

S. Aureus

Hydrogen peroxide is the reagent for what test?

Catalase

Name a test that distinguishes Staph aureus from the other Staph spp.?

Coagulase

A staphylococcus species is tested using the novobiocin disk test. After overnight incubation, the organism has grown all the way up to the novobiocin disk. What organism is this?

Saprophyticus

What is the reagent for the slide coagulase test?

Rabbit Plasma

How does the beta hemolysis appear on a blood agar plate?

A clearing in the agar

The bacitracin disc test is used to differentiate staphylococcus from what other organism?

Micrococcus

If an organism is positive for the beta lactamase test, what are the implications in treating the patient? What antibiotic could or could not be used and why?

It means that the organism would be resistant to the penicillin class of drugs and it could not be used to treat

What is the name of the virulence factor produced by S.aureus that makes the organism capable of blocking phagocytosis?

Protein A

What is the name of the pigment that causes the yellow color seen in many strains of S. saprophyticus?

Lipochrome

What is the other species of Staphylococcus?

S. Epidermis S. LudgendousS. DelphiniS. Hyicus