Lab Final

Front 1

Catalase test:

Back 1

Positive Result:= Bubble formation after placing a drop of hydrogen peroxide on the colony

Negative Result= No bubble formation after placing a drop of hydrogen peroxide on the colony on a glass slide

Front 2

What does Catalase test for?

Back 2

to see if the microbe has catalase, a protective enzyme capable of destroying the dangerous chemical hydrogen peroxide.

Front 3

What is the reagent for catalase?

Back 3

Peroxide

Front 4

Oxidase test:

Back 4

Positive Result = Purple edging effect after Kovac's reagent is added

Negative Result= No edging effect after Kovac's reagent is added

Front 5

What is the reagent for Oxidase?

Back 5

Kovac's

Front 6

What does the Oxidase test for?

Back 6

used in microbiology to determine if a bacterium produces certain cytochrome c oxidases

Front 7

Carbohydrate Fermentation test:

Back 7

Positive Result= Yellow color changes with or without gas production

Negative Result= No color change

Front 8

What does the Carbohydrate fermentation test for?

Back 8

To see is the bacteria can make the specific enzyme required to breakdown each carbohydrate; then it can USE the carbohydrate.

Phenol Red- a pH indicator that changes from red to yellow to indicate acid production ( yielding positive result)

Front 9

Starch Hydrolysis test:

Back 9

Positive Result= A clear halo around the colonies after the addition of Gram's Iodine

Negative Result = The entire medium is dark blue/brown

Front 10

What is the reagent for the Starch test?

Back 10

Gram's Iodine

Front 11

What does the Starch test, test for?

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The purpose is to see if the microbe can use starch, a complex carbohydrate made from glucose, as a source of carbon and energy for growth. Use of starch is accomplished by an enzyme called alpha-amylase.

Front 12

Nitrate Reduction Test:

Back 12

Positive Result for Nitrate ---> Nitrite= Yellow,pink or red color change after the addition of Paba.

Negative Result for Nitrate--> Nitrite= No color change after addition of the Paba

Front 13

What is the reagent for the Nitrate Reduction Test?

Back 13

Paba

Front 14

What is the purpose of the Nitrate reduction test?

Back 14

Nitrate broth is used to determine the ability of an organism to reduce nitrate (NO3) to nitrite (NO2) using the enzyme nitrate reductase. It also tests the ability of organisms to perform nitrification on nitrate and nitrite to produce molecular nitrogen.

Front 15

H2S Production (Peptone) test:

Back 15

Positive Result= growth with black precipitate in the media

Negative Result= growth with no black precipitate

Front 16

What is the purpose of the H2S Production test?

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the microbe reduces sulfur-containing compounds to sulfides during the process of metabolism.

Front 17

Citrate Utilization test:

Back 17

Positive Result= Green to blue color change (citrate was utilized as sole carbon source)

Negative Result= No color change (citrate was not utilized)

Front 18

What is the indicator for the Agar used in the citrate test? And what does the Medium contain?

Back 18

Indicator= bromothymol blue; will detect a pH change greater than 7.5 from the conversion of ammonium dihydrogen phosphate to ammonia and ammonium hydroxide.

Front 19

What is the purpose of the Citrate test?

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Simmons citrate agar tests for the ability of organism to utilize citrate as a sole carbon source.

Front 20

Motility test:

Back 20

Positive Result= fanning out away from the stab line. This can also make the tube look cloudy

Negative Result= No fanning out from the stab line

** there is a dye in the media that shows the color pink for growth.

Front 21

Urea Hydrolysis test:

Back 21

Positive Result= Bright pink slant ( Urea Hydrolyzed, urease is present)

Negative Result= Light orange to yellow color (Urea not hydrolyzed, no urease present.)

Front 22

What is the purpose of the Urea Hydrolysis test?

Back 22

Using Christensen's urea broth, a media containing urea.The purpose is to see if the microbe can use the compound urea as a source of carbon and energy for growth. Use of urea is accomplished by the enzyme urease.

Front 23

Phenylalanine Deamination test:

Back 23

*** reagent =FeCl3

Positive Result= Dark green color on slant (Phenylalanine metabolized to phenylalanine acid, phenylalanine deaminase present)

Negative Result= No color change (Phenylalanine not metabolized, phenylalanine deaminase is not present)

Front 24

What is the purpose of the Phenylalanine Deamination test?

Back 24

Used to detect the presence of phenylalanine deaminase.

Front 25

BEA, Selective and Differential Media

Bile Esculin:

Back 25

Positive Result= Growth (selective) of bacteria with a color change of the media to black (differential; Bacteria able to hydrolyze esculin and survive the bile salts, often Enterococcus spp.)

Negative Result= Growth of bacteria without color change or no growth of bacteria (Bacteria unable to hydrolyze esculin or unable to grow in presence of bile.

Front 26

What is the purpose of the BEA test?

Back 26

To test if the bacteria can survive in the presence of bile and hydrolyze esculin.

Front 27

Mannitol Salt Agar (MSA):

Back 27

Positive Result= Growth of bacteria with a color change of the media to yellow

Negative Result= Growth of bacteria without a color change or no growth of bacteria ( Bacteria unable to tolerate high salt or unable to ferment mannitol)

Front 28

What is the purpose of the Mannitol Salt Agar (MSA) test?

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Isolation of some pathogenic Gram-positive organisms. Selective for salt-loving bacteria and differential for species that can ferment the Mannitol into acid (color change)

Front 29

Eosin Methylene Blue Agar (EMB) Test:

Back 29

Positive Result= Growth of bacteria with a color change of the colonies that have dark centers (magenta or purple) or a metallic green sheen

Negative Result= Growth of bacteria without color change (takes on media color) or no growth of bacteria

Front 30

(MR) Methyl Red test

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Positive= red color change indicating mixed acid production

Negative= no color change

**yellow = neutral environment

Front 31

What is the reagent for Methyl Red test?

Back 31

Methyl Red

Front 32

What is the purpose of the MR test?

Back 32

To look for either acetoin or mixed acid production.

Front 33

What is the purpose of the EMB ager test?

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used in identification and isolation of Gram-negative rods. EMB agar inhibits the growth of Gram-postivie organism (selective), and differentiates bacteria between lactose fermenting and non-lactose fermenting.

TWO indicator dyes: Eosin and methylene Blue

Metallic green sheen = E.coli colonies

Front 34

MacConkey Agar (MAC) test=

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Positive Result= Growth of bacteria with a color change of the media to bright pink

Negative Result= Growth of bacteria without color change or no growth of bacteria

Front 35

What is the purpose of the MAC agar test?

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It is also for the identification of lactose fermenting, Gram-negative enteric organisms, and for inhibiting growth of Gram-positive organisms.

The red color is due to the pH indicators response to the acidic environment created by fermentation of lactose.

Front 36

O/F Test

Back 36

Positive Result=growth in both tubes with and without mineral oil with color change from red to yellow.

Negative Result= No growth or only growth in the tube without mineral oil layer. No color change .

Front 37

Purpose of O/F test?

Back 37

To test for the ability to oxidize and ferment lactose.

Front 38

Lactose, Glucose, Sucrose, Xylose, Trehalose test

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Positive Result= Growth with a color change of sugar broth from red to yellow and production of gas ( gas bubble in the Durham tube)

Negative Result = No growth with no color change nor gas bubble.

Front 39

List of types of Agars used:

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-Sheep Blood Agar (SBA)

-Iron Peptone Agar (PIA)

-Simmon's citrate agar ( SC)

-Christenson's Urea Broth

-Bile Esculin Agar (BEA)

-Mannitol Salt Agar (MSA)

-Eosin Methylene Blue Agar (EMB)

-MacConkey Agar (MAC)

-Brain Heart Infusion Agar (BHI)

-Nutrient Agar (NA)

-Thioglycolate broths

-Tryptic Soy Agar (TSA)

-Mueller-Hinton Agar (MH) *Antibiotic Infused

Front 40

For sugar Agars, what does the +/- mean?

Back 40

the left hand side is for color change, differential, and the right hand side is for gas production ( selective)

Front 41

What does MPN stand for?

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Most probable number of contaminants (water samples)

Front 42

Hemolysis=

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Some microbes contain enzymes that can lyse host cells, especially red blood cells.

---Test is done onSBA plates (Sheep blood agar)

Front 43

Virulence factors

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are molecules produced by pathogens (bacteria, viruses, fungi and protozoa) that contribute to the pathogenicity of the organism and enable them to achieve the following: colonization of a niche in the host (this includes attachment to cells)

Front 44

What was on the poop plate?

Back 44

Tetracycline; therefore, if there was growth, it was a tetracycline resistant anaerobe and a facultative anaerobe ( can grow in the presence of O2 but prefers no O2)

Front 45

High copy number:

Back 45

plasmid that may have up to 300 copies of itself in any one bacterial cell, thus is can produce up to 300 copies of gene product that it carriers in that one bacterial cell.

Front 46

pGlO:

Back 46

a plasmid that contains an ampicillin resistance gene, which codes for the exoenzyme ampicillinase.

Front 47

Alpha hemolysis:

Back 47

incomplete

Front 48

Beta hemolysis=

Back 48

complete

Front 49

transformation:

Back 49

to move DNA around

Front 50

What did the CaCl2 do in the experiment with transformation?

Back 50

Brings plasmids to cell wall so that when the sample is heat shocked, the pores open and the plasmids can enter.

Front 51

AMPr gene:

Back 51

encodes for an ampicillinase ( becomes resistant to ampiciline)

Front 52

pGLO gener -->

Back 52

GFP-Green flouresent protein (isolated in bioilluminesent; potential to glow)

---only transcribed/ translated in the presence of arabinose---> inducer (like an operon)

Front 53

Indicator organism

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is one which is present in human waste in high enough numbers to be readily detected and east to find

Front 54

Coliforms:

Back 54

are aerobic or facultatively anaerobic gram negative rods. They do not form endospores and they ferment lactose which leads to acid and gas production within 48 hours of incubation at 35 degrees Celsius.

Front 55

multiple tube technique:

Back 55

a way to detect Coliforms. Involves two tests; a presumptive test in lactose broth and a confirmation test. Those tubes that test positive in the presumptive test (acid and gas production) go on to be confirmed using MUG (methylumbelliferyl-B D glucuronide) agar or EMB ( Eosin Methylene Blue) agar.

Front 56

Gram Stain procedure:

Back 56

Crystal Violet

Rinse

Grams iodine

Ethanol

Rinse

Safranin

Rinse

Front 57

Dilutions equation:

Back 57

CFU= # of colonies / (amount plated)(dilution factor)

*** divide every time by 10 then; multiply each total to give the final mL. Plug in that ML for "dilution factor) the amount plated is a CONSTANT : 0.1 remember only can be 30- 300 colonies to be used for calculations.

Front 58

Microaerophiles:

Back 58

require low concentrations of O2 fro growth. However, higher oxygen concentrations will inhibit heir growth and they cannot grow in the total absence of oxygen.

Front 59

Capnophillic organisms:

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prefer higher concentrations of CO2

Front 60

Reservoirs

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are humans or animals that are sources of infection.

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Vectors

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Diseases transmitted by insect and arthropod

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Mechanical Transmission

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occurs when an insect carriers fecal pathogens on its feet and then walks on food.

Front 63

Biological transmission

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occurs through the bite of an infected mosquito, tick, or flea

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Endemic

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diseases are present in a population all the time at low levels.

Front 65

Zoonoses

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are diseases of animals that can spread to humans.

Front 66

aseptically

Back 66

without introducing other microbes

Front 67

Autoclave

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steam and pressure. heated to 121 degrees C at 15 psi. for 15 mins can kill all microbes including spores.

Front 68

Psychrophile-

Mesophile-

Thermophile-

Back 68

Cold-loving

Middle-temp loving

Heat-loving

Front 69

Disk-diffusion method

Back 69

used to determine the effectiveness of some antibiotics on certain bacteria