Lab Quiz 3

DNase

test uses methyl green to test if the organism can depolymerize DNA

Nitrate

This tests for if the organism has Nitrate reductase and/or nitrite reductase. if red after incubation it is positve because of nitrate reductase. if colorless then add zinc. when zinc is added if there is nitrate then it will turn red meaning a negative result. If it is still colorless then it is positive because it was reduced into ammonia or nitrogen gas

Phenylalanine Deanimase test

this test removes NH2 amino group and makes NH3 and pyruvate. Then acidified ferric chloride solution is added to react with pyruvate proving that the organism could make energy.

Bacteria Agglutination

using antibodies to make the bacteria agglutinate with each other and latex beads to intensify the reaction of antibodies binding to the bacteria.

Coagulase

This test uses plasma to check if the microorganism can agglutinate fibrin into fibrinogen.

Indole

This test checks for the protein metabolism making tryptophan into indole, pyruvate and ammonia. then Kovacs reagent is used to color the indole and makes a reddish layer

Methyl red

This test was for carbohydrate fermentation and checks if its PH increases with a Methyl red Indicator.

Voges Proskauer test

This test checks for fermentation and if the organism has made acetocin. if so, it turns pink

Citrate

This tests if the organism can grow in an organic acid

Urease

this test checks for urease and whether it breaks down the urea into co2 and ammonia. if it changes to pink that means it has the enzyme.

Catalase

this test checks if an organism has the enzyme to break down hydrogen peroxide into water and oxygen. if it does it will make gas bubbles.

Hydrogen Sulfide

this test checks if the organism can remove sulfur from amino acids. If they can they relase H2S gas. This gas is mixed with iron and will make a black percipitate.

Oxidase

this test checks if an organism has an enzyme that is found in the electron transport chain in bacteria using cytochrome C

Carbohydrate Fermentation

test whether the organism can ferment either glucose and lactose. if positive acid will be formed and there may or may not be gas in the durham tube.

Digestive Exoenzymes

this test checks if the bacteria has enzmes that allow it to hydrolyzes starch, and the if it can degrade gelatin. Iodine is used to detect if the enzyme that hydrolyzes starch is present.

Oxygen requiremnents

This uses thioglycollate broth in order to test what type of respiration a type of microorganism uses

bacterial motility

this test whether the bacteria is able to be motile using a motile deep

Lysine

this test checks if the organism can do decaboxylization which then can then translate into cadaverine and uses a PH indicator of Bromosol purple. which will turn lavender if pos

Ornithine

this test checks if the organism can do decaboxylization which then can then translate into putrescine and uses a PH indicator of Bromosol purple. which will turn lavender if pos