Microbiology Lab - Gram-Positive ID

catalase test

test done to determine whether a gram positive bacteria belongs to genus staphylococcus or streptococcus

oxygen bubbles

a positive catalase test is indicated by the presence of?

no oxygen bubbles

a negative catalase test is indicated by the presence of? 

Staphylococcus

a positive catalase test result means that the microorganism belongs to genus?

Streptococcus

a negative catalase test result means that the microorganism belongs to genus?

superoxide dismutase

what is the enzyme that breaks down superoxide free radicals to hydrogen peroxide?

catalase

what is the enzyme that breaks down hydrogen peroxide to water and oxygen?

slide; loop

a catalase test is performed on a _____, with a ____ used for inoculationh

hydrogen peroxide

what must be added to the slide with the organism on it to allow catalase to begin breakdown?

Staphylococcus aureus

very pathogenic microorganism, can cause many diseases of the skin, lungs, bone and bone marrow, endocardium, kidneys, bladder, etc

Staphylococcus saprophyticus

an opportunistic staphylococcus microorganism, lives in the colon (specific epithet means living in dead/decaying material)

Staphylococcus epidermidis

opportunistic staphylococcus microorganism, part of the resident flora of the skin

Staphylococcus capitis

opportunistic staphylococcus microorganism, resident flora of the head and neck

coagulase

enzyme that produces a blood clot to protect microorganism from damage by immune cells 

fibrinolysin

aka Staphylokinase; enzyme that breaks apart the blood clot, allowing the microorganism to travel deeper into the body

Mannitol Salt Agar (MSA) test

questions asked for this test: Is the microorganism salt-loving (halophilic)?

Can it ferment mannitol?

Blood Agar Plate

hemolysis tests are performed on a?

Mueller Hinton agar

what is the preferred media for novobiocin sensitivity testing?

S. saphrophyticus

Novobiocin is the antibiotic to identify? (resistant)

Kirby-Bauer disk-diffusion

a method used to determine the drug sensitivity/susceptibility of microorganisms

zone of inhibition

the area surrounding the placement of the antibiotic which diameter determines whether a microorganism is sensitive or resistant to a drug

sensitive

S. auereus and S. epidermidis are (sensitive/resistant) to Novobiocin, evident by the larger zone of inhibition surrounding the antibiotic

resistant 

S. saprophyticus is (sensitive/resistant) to Novobiocin, evident by the smaller zone of inhibition surrounding the antibiotic

RNAse

while staphylococcus aureus contains the enzyme lipase, streptococcus pyogenes contains the enzyme..?

gelatinase

where streptococcus pyogenes has the enzyme hyaluronidase, staphylococcus aureus has the enzyme..?

erythrogenic toxin

where staphylococcus aureus has an enterotoxin, streptococcus pyogenes has..?

Streptococcus pyogenes

this beta-hemolytic microorganism can cause infections such as tonsillitis, bronchopneumonia, scarlet fever, or rheumatic fever

Streptococcus agalactiae

a beta-hemolytic microorganism typically found in vaginal mucosa that have been shown to be responsible for puerperal fever, neonatal meningitis, and endocarditis

Streptococcus salivarius

a microorganism that is resident flora of the mouth and gums, and can cause cavities and periodontal disease 

Streptococcus pneumonia

a microorganism that may be found in the throat of healthy carriers, causes pneumonia

C-substance

Rebecca Lancefield classified the streptococci into 20 subgroups, based on the presence of an antigenic determinant called the?

A,B,C,D

what four groups of streptococci are responsible for causing infection in humans?

negative

Streptococcus salivarius is catalase (positive/negative)

Enterococcus durans

previously known as Streptococcus durans, catalase negative, can cause bacteremia originating from the urinary tract

Bacitracin

what is the antibiotic used to identify S. salivarius?

Bacitracin Sensitivity Test

antibiotic sensitivity test for streptococcal species

6.5% NaCl broth test

selective test that answers the question: is the microorganism salt-tolerant? (Haloduric)

Bile esculin test

test used in differentiation of streptococcal species, selects for bile tolerant bacteria and differentiates between bacteria converting/nonconverting esculin to esculetin

black

the conversion of esculin to esculetin gives of what color?