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35 terms

Microbiology Lab Exam 2

STUDY
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What is the Medium for Motility Test?
Motility Test Medium
What is the indicator for the Motility Test?
Trazolium Chloride (TTC) - it is an oxidation indicator
Would a red cloudiness be a + or a - in the Motitlity Test?
Positive
KOH stands for?
What is the main purpose?
What is the Medium?
Do we use a wax ring?
How long do we mix?
G- Result?
G+Result?
Potassium Hydroxide
To see if it is a G- or G+
Nutrient Agar
NO
2 minutes
stringy
non-stringy
What is the substrate for a Catalase Test?
What is the Exo-enzyme
Products?
Why were these products produced?

Do we use a wax ring?
Positive Result?
Negative Result?
H2O2- Hydrogen Peroxide
Catalase
Water and Oxygen Gas
Because Catalase is an enzyme of aerobes and facultative anaerobes that converts H2O2 to H20 and O2 gas.
Yes
Bubbles
No Bubbles
What is the medium for the Indole Test?
What are the reagents?
What is the substrate?
Exo-Enzyme?
What is the by product?
What is the Product?
What does a positive test look like?
Why is this test performed?
Indole Broth
Kovac's Reagent
Tryptophan
Tryptophanase
Indole
Pyruvic Acid, Ammonia, and Indole
Red/Orange + and Yellow-Greenish is -
To identify bacteria that possess the enzyme tryptophanase. If they do they can hydrolyze tryptophan to pyruvic acid, ammonia and indole as a by-product.
What is MR short for?
What is the Medium?
What is the Reagent?
This reagant is also a ?
What is a positive result look like?
This test tells us if ____________were produced from glucose fermentation
Why do we use this test?
Methyl Red
MR-VP Broth
12 drops of Methyl Red
pH indicator
Red
stable acids

to identify bacteria that are mixed acid fermenters of glucose.
What is VP short for?
Why do we use this test?

What is another name for Acetoin?
What are the Reagents?
How long does this test take?
What is positive result?
Vogues - Proskauer
Idenitifies organisms able to produce acetoin from degredation of glucose.
Acetylemethylcarbinol
12 drops of napthol and 4 drops of 40% KOH
up to 2 hours
A red color will appear, this means there was an acetoin production.
What is the purpose for the Citrate Utilization Test?
What is the Medium?
What is the pH indicator?
Exo-Enzyme?
Blue is (+), what is the pH?
Green is (-), what is the pH?
What happens metabolically for the cell?
To identify bacteria that use citrate as their carbon source.
Simmon's Citrate Agar (Slant)
Brothymol Blue
Citrase
7.5 or higher
6.9 or lower
In the presence of citrate, citrate enters the cells and is converted to Pyruvate. Pyruvate is then converted to a variety of products depending on the pH of the enviroment.
What is the purpose for the Oxidation Test?

What is the medium?
What is the substrate?
What is the Exo-Enzyme?
What is the Product?
What is a positive result?
To identify bacteria containing the respiratory enzyme cytochrome oxidase.
Nutrient Agar Plate
Phenylinediamine reduced
Cytochrome Oxidase
Phenylendiamine oxidized
Is blue within seconds
What is another name for the Amylase Production Test?
What is the medium?
What is the Substrate?
What is the Exo-Enzyme?
What is the Product?
What are the Reagents?
What does a positive result look like?
Starch Hydrolysis Test

Starch Agar - "S" on plate
Starch
Amylase
Simple Sugars ( monomoer's and disaccharides)
Gram's Iodine
When hydrolysis of Starch has occurred there will be a clear zone around streak.
What is another name for Sulfur Reduction Test?
What is the Medium?
What are the Substrates?
What are the possible Exo-Enzymes


What are the products?
What is the Differential Ingredient?
What precipitate is formed?
What does positive result look like?
H2s Production Test
SIM Agar Deep
Sulfate and Cysteine
If there is a reduction of Thiosulfate then it is Thiosulfate Reductase, If there is a putrefaction of Cysteine then it is Cysteine Desulfurase.
H2S and Ferric Sulfate
Ferric Sulfate
Ferric Sulfide
Black precipitate
What is the Medium for the Urease Test?
What is the pH indicator?
What is the substrate?
What is the Exo-Enzyme?
Product that is produced?
What does a positive result look like?
Urea Broth
Phenol Red
Urea
Urease + H20
Ammonia and CO2
Pink= alkaline + hydrolysis of urea
Yellow or Orange = Acidic -
What is the Medium for Nitrate Reduction Test?
After incubation, what is produced for a + result?
What occured?
Reagents?
After adding reagents, positive result is......
If negative add.....
Positive Result is?
What are the 5 possible products?
Nitrate Broth - had Durham Vial
NO2 Bubble
Denitrification
4 drops of Sulfanilic Acid and 4 drops of napthylamine
If Nitrite is present then it will be pink or red color +
Zinc Powder
If there is no color = + if there is red then = -
Nitrite, Ammonia, Nitric Oxide, Molecular Nitrogen, Nitrous Oxide
What is the DNase test used for?

What is the Medium?
What is the Indicator?
Substrate?
What is the Exo Enzyme?
What is the Product?
What is a positive result?
To identify bacteria that produce DNase, which catalyzes depolymerization of DNA into small fragments
DNase Test Agar
Methyl Green
DNA
Deoxyribnuclease DNase
Nucleotide
Clear area around microbe, no green
What are the other names for Gelatin Hydrolysis Test?
What is the substrate?
What is the Exo-Enzyme?
What is the Product?
If there is no change in the medium, is that a +or -?
Gelatinase Test, Gelatin Liquefication
Gelatin
Gelatinase
Amino Acids
Runny = +
Not Runny = - for gelatinase
What is the Medium for Growth on a Slant?
What are the possible forms?
Nutrient Agar Slant Filiform,
Arborescent, Beaded, Effuse, Rhizoid and Echinulate
What is the medium for the Carbohydrate Fermentation Test?
What are the 4 Variations:
What is the pH indicator?
Is this test positive, what is it positive for ?
What are the possible results?
PRB

PRB + Lactose, Mannitol, Glucose, Sucrose
Phenol Red
Fermentation of Carbohydrates
Orange = A negative NC-
Pink = - Alkaline ALK-
Yellow= Positive Acidid-A+ or with bubble AG+
What is the Lipase test used for?
What is the Medium?
What is the Substrate?
What is the Exo-Enzyme?
What is the Product?
What does a positive result look like?
Used to identify bacteria capable of producing the exoenzyme lipase to hydrolyze fats.
Tributyrin Agar - "T" on plate
Tributyrin
Lipase
Glycerol and Fatty Acids
Clear zones around microbe = lipase prod. +
No clear zone=no lipase prod. -
What was the medium used in The Temperature Effects Test?
What temperature's were used?
What are the possible categories of the microbes?
Nutrient Agar

5C, 25C, 37C, and 50C
Thermophile - optimum growth at 40C or higher
Mesophile - optimum growth at 20C - 40C
Psychrophile - optimum growth at 20C or less
What was the Medium used in the Osmotic Pressure Effects?
Which is ____+_________
What temperature did we incubate at?
What were the concentrations?
Non-Halophile only grows on......
Facultative Halophile grows on ...........
Obligate Halophile only grows on.......
Salt (NaCl) Agar Plate

Nutrient Agar and Sodium Chloride
37C
5%,7.5%,10%
isotonic solution
low or moderate or no salt
salt requiring
Net diffusion that is into the cell, swells protoplast, can cause osmotic lysis __________

Net diffusion is out of the cell and shrinks the protoplast away from the cell well creates plasmolysis_________

Equilibrium is ___________
Hypotonic


Hypertonic



Isotonic
What is another name for Atmospheric O2 Requirements?
What is the Medium?
This medium is special because the )2 has been boiled away, its called a _________medium
What is the oxidation indicator?
What are the 2 zones called?
What else do we use on the outside of the tube?
Aerotolerance

Thioglycollate Agar

Reducing
Resazurin
Aerobic Zone and Anaerobic Zone
A certain plastic wrap
What are the different types of results from the Aerotolerance test?
Aerobe: Growth on Surface
Facultative Anaerobe: Growth in Aerobic and Anaerobic Zones
Strict Anaerobe: Growth only in anaerobic zone
Aerophile: growth just below surface of aerobic zone
What type of medium was used for our Environmental Streak Plates?
What pattern did we use?
What temperature did we incubate at?
Nutrient Agar

Single Zig Zag or fishtail Streak pattern
25C
Quadrant Streak Plate Pattern?
How many loopfuls?
Why do we do this?
Quadrant Method
1
To isolate and pure a colony
What does FEMOC stand for?
Form, Elevation, Margin, Opacity, and Color
What are the 3 ph indicators we used?
Phenol Red, Methyl Green, Brothymol Blue
Which tests had media in a deep?
Gelatinase Test, Aerotolerance, Sulfur Reduction, Motility Test
Which 2 tests have media in a slant?
Citrate Utilization and Growth on a slant
If a petri dish has T on it what is it?
If a petri dish has S on it what is it?
Trybutyrin Agar
Starch Agar
On a qualitative scale, a 3+ would mean?

+/- means?
75% of streak line is filled

Scant growth
For which tests do we use the vortex mixer?
Nitrate Reduction Test, MR Test, VP Test, Indole Test
What is a Differential Media?


What is Complex Media?

What is Selective Media?
Media that contains 1 or more ingredient which change color as a result of microbial growth, activity or chemical reactions. e.x Thioglycollate
One which contains a variety of nutrients. ex. carbs and proteins. Generic type of Media
Contains 1 or more ingredient and promotes some microbes but inhibits the growth of others.
What was the Medium used for the Hemolytic Bacteria Test called?
What is another name for hemolysins?
What are the different types of hemolysis?
Blood Agar - Tripticsoy Agar, comprised of Animal protein, Plant protein and 5% sheep blood
Exotoxins. Streptococcus is called streptolysins
Alpha Hemolysis - partial destruction of RBCs. Brown/greenish darkening around colony
Beta Hemolysis - complete destruction of RBC's. No Red
Gamma Hemolysis - No Hemolysis. No change in Red Agar