Micro Lab 2
Card Set Information
Micro Lab 2
Lab Exam 2
Skim milk agar is a test for a _______ type enzyme.
The protein in skim milk is _______ and a positive test for its digestion is _______.
This plate is used to test for the type of digestive enzyme called ________ because it breaks down _______ to ___________.
lipase; lipids; fatty acids & glycerol.
This slide is test is used to detect the enzyme _______ . The substrate is ________ and the end product is _______.
catalase; H2O2; O2
Which gram positive coccus produces a negative result for this test? Which is positive?
What is the indicator in this media?
What color is it if it is "acid"?
Phenyl Red; yellow
What type of end product does fermentation produce? What color does it change the indicator to?
The small tube in the broth is called a ________ and will collect _______ produced in fermentation reactions.
fermentation tube; gas
Gelatin is a ______ derived from animals. This test detects the enzyme ______ that digests the material.
protein; gelatinase or protease
A positive nutrient gelatin test is described as _______ after inocculation & incubation & chilling in the refrigerator. Which tube below is (-) for the digestive enzyme?
liquid; B & C
In the starch test, the name of the starch used is ______ and the enzyme we are testing for is called ________.
In a starch test, the end product of starch hydrolysis is _______.
What reagent is added after incubation to see the positive test in starch hydrolysis?
In this test, E. coli is (+) or (-) for starch hydrolysis? Why?
negative; no ZOC
The indicator in a urease test is ________ and is ______ if positive.
phenyl red; hot pink
Describe the positive starch test.
The pH of a positive urease test is ________.
Urea is produced by the _________ .
deamination of amino acids that make up proteins
Microbes can degrade urea. What are the two end products of the digestion of urea?
NH3 (ammonia) and CO2 (carbon dioxide)
What is a defined media? What is an example of one?
It means we know exactly what is in it;
Simmons citrate media
The only source of carbon in simmons citrate media is ________.
citric acid (or citrate)
A positive test in simmons citrate media is described as ______.
What does a positive simmons citrate test mean?
The organism produces the enzyme citrate permease and can use citric acid as the SOLE source of carbon.
What is the indicator in a simmons citrate test?
What is the pH of the positive tube?
Which tube is (+) for MR? WHat's the name of the indicator added after innoculation and incubation?
B (b/c its red)
What is the pH of the positive MR test?
What enzyme system is being tested here?
Name 3 end products of the nitrate reduction test.
What is the sugar in high concentration in the MR-VP media?
Describe the positive VP test.
What is the name of the reagents added after innoculation and incubation in the VP test?
Barrit's A & B
Name one coliform enteric that is positive for VP.
E. Cloachae (see flow chart)
The MR-VP tests are part of the ______ battery of tests to separate coliforms into two categories for further testing and identification.
What are the 3 tests for SIM media?
sulfur, Indole, motility
In SIM media, what color is a positive for "s" ?
What is added to the SIM media?
Iron is added to the SIM media to react with _______ produced from the breakdown of _____ containing amino acids.
Hydrogen Sulfide (H2S)
A positive "I" is a _______ color after the addition of _______ in SIM media.
The red ring color in SIM media after adding kovacs is the result of the break down of what?
the amino acid tryptophan
A positive "M" in SIM media is described as what?
A SIM media is innoculated with a _____ because it is a _____.
The "base" medium in decarboxylase media is _______.
The indicator in decarboxylase media.
In a decarboxylase test, a (+) test is ______ and indicates an ______ pH.
What is added to decarboxylase test media after innoculation and BEFORE incubation and why?
mineral oil to seal out the air
TSI stands for?
Triple Sugar Iron
The 3 sugars in TSI.
glucose, sucrose, lactose
How much glucose is in TSI compared to sucrose & lactose?
1/10 as much
The indicator in TSI media.
Phenyl red in TSI media indicates _________ end products when the color is YELLOW.
Which tube is positive for glucose fermentation only? Why?
The 2nd one from the left;
acid butt (yellow) but has an alkaline slant
What pathogen would produce an acid butt (yellow) and alkaline slant (red) in TSI media?
Which TSI tube indicates hydrogen sulfide production?
The 3rd from left because it's black
What is added to TSI media to make the black color show up?
Which tube is showing lactose fermentation (TSI media)? Why?
1st on left - because it is acid-acid & has gas at the bottom
Which tube is showing no fermentation (TSI media)? Why?
One on far right - it's red.
Phenylalanine is an _______.
What is the reagent added in phenylalanine deaminase that is added after innoculation & incubation to see a positive deaminase rxn?
The positive phenylalanine deaminase test is a ______ color.
The end product of phenylalanine deaminase is __________.
Pheynol pyruvic acid
DNASE plates test for the presence of what enzyme?
The indicator in a DNASE plate is ________ and a positive DNASE is described as a ______.
A pathogen that is positive for DNASES.
What two enterics would be (+) for hydrogen sulfide in a TSI test?
salmonella & proteus
Which specific other test would you run to separate salmonella & proteus?
When running a urease test to separate salmonella & proteus, what color would a (+) test be?