Microbiology Lab Final

MAC positive

Lactose fermenting, pink and growth

MAC semi positive

Non-Lactose fermenting, colorless but growth

MSA negative

Does not grow on salt and no color change

MSA Positive

Growth and yellow able to grow on salt (Staph. Aureus)

MSA semi positive

Grows on salt does not change color (Staph. Epiderminis)

BAP alpha

Green

BAP beta

Clear or see through

BAP gamma

Grey or no change

TSIA negative

Red slant Red butt K/K

TSIA semi postive

Yellow slant Yellow butt A/A

TSIA all around positive

Yellow slant (Yellow butt if black) A/A +gas +h2s

SIM medium

Determines mobility, indole formation and H2S production

SIM all around positive

Black bottom and red ring (black bottom is automatic mobility)

SIM all around negative

No red, stick remains the same, no black

OF Glucose postive

Both tubes yellow (Fermentative and oxidative)

OF Glucose semi positive

Oil tube has no change, other tube yellow (Oxidative)

OF Glucose negative

Both tubes green No glucose metabolised

Negative CF

Red (no change in tube)

Semi positive CF

Yellow (Change in tube no gas made)

Positive CF

Yellow with gas production

Positive citrate test

media turns blue

Negative citrate test

Media remains green

Positive Urease Test

Media turns Magenta/Pink

Negative Urease Test

Media remains Light Orange/Orange

Methyl Red Positive

media turns red

Methyl Red Negative

Media remains Yellow

VP Test Postive

Media makes red ring

VP Test Negative

Media remains yellow (no red ring)

Catalase test positive

Hydrogen peroxide bubble reaction

Catalase test negative

No hydrogen peroxide reaction

Positive coagulase test

clots - indicates staph aureus

what is identified through the bacitracin test

Group A streptococcus pyogenes. Everything else does not have any bacitracin

CAMP Test

Identifies group B streptococcus agalactiae based on their formation

Positive CAMP test

Arrow head close to line

Negative CAMP test

No response just a line

Purpose of Mannitol Salt Agar

Selective for species that can grow on salt and changes colors for mannitol fermenters to yellow

Purpose of Macconkey Agar

Selective for Gram negative species and determines lactose fermenters changing color to pink

Purpose of Blood Agar Plate

Differential media that shows hemolysis or how an organism uses blood cells

Purpose of Phenylethyl Alcohol Agar

Selective media that only grows Gram Positive organisms

Purpose of Eosin-Methylene blue agar

Selective for Gram negative species and determines lactose fermenters changing color to purple (green or metallic = E.Coli)

Purpose of Cytochrome Oxidase Test

To determine if an organism uses cytochrome turning purple if positive. If negative the organism is part of the Entrobacterase family

Purpose of Coagulase Test

Used to differentiate Staph.aureus and Staph. Epiderminis.

Purpose of Bacitracin Disk Test

Determines if bacteria are resistant or sensitive to bacitracin and identifies Strep. pyogenes

Purpose of Triple Sugar Iron Agar Test

Determines if an organism uses Lactose, Sucrose and Glucose and to produce H2S gas

Purpose of Sulfide Indole Mobility Test

Determines if an organism produces H2S gas, indole formation and mobility

Purpose of Kirby Bauer Test

To determine antibiotic susceptibility and which antibiotics work for each bacteria

Purpose of Phenol Red Glucose Test

Used to determine if a bacteria can ferment glucose and produce carbon dioxide gas

Purpose of Phenol Red Lactose Test

Used to determine if a bacteria can ferment lactose and produce carbon dioxide gas

Purpose of OF Basal Glucose Test

Used to differentiate between oxidative and fermentative bacteria under anaerobic and aerobic conditions

Purpose of Decarboxylase (Arginine, Ornithine, and Lysine) Test

Determines if bacteria can break down amino acids and make the environment alkaline

Purpose of Citrate Test

Determines the ability of bacteria to utilize sodium citrate

Purpose of TSOY Broth Test

Used to determine indole production

Purpose of Methyl Red Vogues Proskauer Test

Determines if a bacteria can ferment glucose. MR produces acid changing to red color. VP determines the presence of acetoin

Purpose of Urease Test

Determines if the bacteria is able to produce the enzyme urease which breaks down ammonia and carbon dioxide

Purpose of Nitrate Test

Determines if the bacteria can reduce nitrate

Purpose of Catalase Test

Determines if a bacteria is a Strep or Staph through hydrogen peroxide