Micro Lab Practical 2

Front 1

The only sugar available to fermenters growing in a Phenol Red Lactose Broth is lactose. Therefore, only bacteria capable of fermenting lactose will produce { } in this broth.

Back 1

Acid

Front 2

Utilization media are designed to test the ability of an organism to:

Back 2

Grow in the presence of a single essential nutrient

Front 3

Catalase is an enzyme that breaks down hydrogen peroxide into

Back 3

Water and oxygen

Front 4

What is the function of the Durham tube inside a Phenol Red Tube?

Back 4

To indicate gas production

Front 5

The pH indicator bromthymol blue is used in the ( ) test.

Back 5

Simmons citrate agar

Front 6

The purpose of ferric citrate in the Bile Esculin Azide Agar is to

Back 6

Detect esculetin and form a dark brown color change

Front 7

True or False- in the Simmons Citrate Agar, lactose is the only carbon source

Back 7

False

Front 8

True or False- in the Phenylalanine test, the formation of a green color after incubation and addition of ferric chloride reagent indicates that phenylalanine has been deaminated

Back 8

True

Front 9

The alkali color of a Phenol Red broth is red and the acid color is

Back 9

Yellow

Front 10

A tube of TSB with 6.5% NaCl will be used for what test?

Back 10

Osmotic pressure test

Front 11

Describe a positive coagulase test

Back 11

Plasma is clotted

Front 12

What is a positive urea test and what does it mean

Back 12

A positive urea test has a bright pink tube and it is alkaline. Positve for amonia.

Front 13

The SIM tube tests for 3 things. What are they and how can you tell a positive test for each?

Back 13

1.Sulfur Reduction- (+) test is really dark, almost black

2. Indole Production- (+) test has a ring of pink at top

3. Motility- (+) test shows growth outside of stab line

Front 14

Describe A/A +G in TSI test

Back 14

Acidic- (+) for Glucose, Lactose or Sucrose

Over same thing

Has gas production

Front 15

Describe K/A +H2S

Back 15

Alkaline

Over

Acid- (+) for glucose then switched to peptone metabolism

Sulfur indicated

Front 16

How can u tell a (-) starch test?

Back 16

After iodine is added there will not be a clear ring around bacteria

Front 17

What is meant by the term "beta hemolysis"

Back 17

Beta hemolysis means there is a complete hemolysis of RBC's

Front 18

When obtaining results of the antimicrobial sensitivity tests, the inhibition zone diameters will be measured in which units

Back 18

Millimeters

Front 19

The antibiotic sensitivity (susceptibility) test is known as

Back 19

Kirby-Bauer method

Front 20

The antimicrobial sensitivity test is a

Back 20

Disk diffusion test

Front 21

Name 3 components of the antimicrobial susceptibility test that are standardized

Back 21

1. Agar depth

2. Agar pH

3. 0.5 McFarland Standard

Front 22

Explain bacteriostatic

Back 22

They stop the growth, but don't kill

Front 23

How do u provide aerobic conditions for certain compartments of the Enterotube ll following inoculation

Back 23

Use the needle that came out of the middle of tube and poke holes in the plastic over the compartments that u want to have aerobic conditions

Front 24

In the Enterotube ll, a reagent must be added before reading the result of the...

Back 24

H2S/Indole chamber

Front 25

If 2 species are initially identified with the same numeric code using the Enterotube ll, then a confirmatory ( ) test is performed to differentiate betwn the 2 organisms.

Back 25

Voges-Proskauer

Front 26

True or False- the Enterotube is inoculated using the loop in your drawer

Back 26

False

Front 27

The Enterotube ll is used to identify a member of the family. ..

Back 27

Enterobacteriaceae

Front 28

What is a bacteria that grows into a clump of cells

Back 28

CFU- colony forming unit

Front 29

What is a countable plate

Back 29

Btwn 30 and 300 colonies

Front 30

What is the preferred method of urine collection

Back 30

Clean catch

Front 31

What is bactururia

Back 31

Presence of bacteria in urine

Front 32

What is Serial Dilution

Back 32

10- fold reduction in cells using water blanks

Front 33

What is OCD

Back 33

# of bacteria in original pt sample

Front 34

What is a volumetric loop

Back 34

Streaking tool made to hold a specific volume

Front 35

Modified streak plate with volumetric loop

Back 35

Front 36

What is used for the salt tolerance test

Back 36

Osmetic Pressure Test- Osmosis

Water moves through a cell membrane from high concentration to low concentration.

Front 37

What does the osmotic pressure test look for?

What does a positive test look like?

Back 37

-Test looks for organisms that are halophiles.

-Positive test shows little cloudy and settled at the bottom- TSB 6 1/2% salt

-TSB control tube has some cloudy growth

Front 38

How to do Osmotic Pressure Test

Back 38

Inoculate saline medium tubes w/ Halobacterium broth using a sterile transfer pipette w/ 1mL of organism. Keep one uninoculated tube. Inoculate all tubes at 35+2degree C for 48 hours. Mix broth gently and check for turbidity, not color.

Front 39

What is important for control tube in osmotic pressure test (salt tolerance test)

Back 39

Plain TSB needs to be (+) when you compare contol to salt tube. If control tube is (-) then it's an invalid test. HAVE to HAVE (+) TSB control tube!

Front 40

What does Bile Esculin Agar test do?

Back 40

Differentiates different organisms. The bile in tube will select against gram (+).

Gram (-) will grow. Add sodium azide to inhibit growth of gram (-).

Front 41

How does Bile Esculin Agar work?

Back 41

Test selects for Enterococcus. Use nutrient called esculin in tube. If bacteria wants to live in the tube it has to convert esculin into glucose and esculetin. Glucose goes away and esculetin is left in the tube. BLACK test tube is (+), no darkening of tube is (-).

Front 42

Phenol Red Broth

Back 42

Phenol Red broth is a differential test medium prepared as a base to which a carbohydrate is added. Included in the base medium are peptone and the pH indicator phenol red. An inverted Durham tube is added to each tube as an indicator of gas production. Keep one uninoculated tube for comparison.

Front 43

Test results for Phenol Red

Back 43

pH indicator is phenol red

Red at neutral

Yellow at acid-(+)

We use lactose, dextrose, & sucrose (dextrose is same as glucose)

Front 44

PR results

Yellow broth, bubble in tube

Back 44

Fermentation w/ acid and gas end products

Symbol= A/G

Front 45

PR test results

Yellow broth, no bubble in tube

Back 45

Fermentation w/ acid end products; no gas produced

Symbol= A/-

Front 46

PR test results

Red broth, no bubble in tube

Back 46

No fermentation

Symbol= -/-

Front 47

PR test results

Pink broth, no bubble in tube

Back 47

Degredation of peptone; alkaline end products

Symbol= K

Front 48

Phenol Red pic

Back 48

Front 49

Catalase test

Back 49

Catalase test is used to identify organisms that produce the enzyne catalase. It breaks down peroxide into water and oxygen

(+) catalase= bubbles

After adding peroxide don't forget to cover slide with lid of petri dish

Front 50

Citrate test

Back 50

Citrate tests to see if organism can break down citrate & convert it to pyruvate. pH indicator is bromothymol blue dye

Front 51

Citrate test results

Back 51

Blue tube is (+)

Blue alkaline products were produced

Green tube is (-)

Uninoculated tube is also green

Front 52

Phenylalanine Deaminase Test

Back 52

To see if organism can use phenylalanine . Act of pulling off amino group is deamination. Pulling off a nitrogen group. Streak 2 slants

Front 53

Phenylalanine test results

Back 53

If u add ferric chloride and it turns dark green then it's positive.

Negative has no reaction.

Front 54

Starch Hydrolysis (amylase test)

Back 54

Main nutrient is starch, bunch of glucose. Just need to pluck off glucose w/ amalase. Add iodine to starch agar after incubatio

Front 55

Starch Hydrolysis test before iodine

Back 55

Front 56

Starch Hydrolysis test after iodine

Back 56

Clear glow on left (halo) - (+)

Right w/o clearing- (-)

Front 57

Urea Hydrolysis (urease test)

Back 57

This test is used to differentiate organisms based on their ability to hydrolyze urea w/ the enzyme urease. Use water and urease to break apart urea molecule. Urea is a byproduct of protein motabolism (waste product). Add pH indicator= phenol red

Front 58

Urea Hydrolysis test results

Back 58

Red- neutral

Yellow- acidic (-) no urea hydrolysis

Pink- basic (+) amonia building up in tube, rapid urea hydrolysis

Front 59

SIM Medium

Sulfur reduction, indole production, motility

Back 59

》Motility- growing away from stab line (+) & dark brown (+) = motile

Solid stab line= (-) for motility

》Sulfur- amino acid cysteine

Iron (phyric sulfate) added to tube

Black= (+)

Not black= (-) for sulfur

》Indole Production- add reagent called Kovac's

Cherry red= (+) indole test

Nothing is (-) indole test

Front 60

Triple Sugar Iron

3 sugars- glucose, lactose, sucrose

Glucose very small %- 0.1%

Lactose- 1%

Sucrose- 1%

Back 60

Peptone in tube (protein product)

Iron in tube (sulfur test)

pH indicator- phenol red

All organisms use glucose to start

Yello-ferment glucose, stays yellow if like lactose or sucrose

Aerobically (only like glucose), slant back to orange

Any bubbles or breaks- gas positive

Black tube (+) for sulfur reduction but only happens in acidic conditions

Front 61

How to record triple sugar iron agar/ kligler iron agar

Back 61

Slant/butt

A= acid/ yellow

K= pink or red/ alkaline

Black is H2S

If black add +gas, +H2S

Front 62

Blood Agar

Back 62

Allows differentiation of bacteria based on their ability to hemolyze RBC's

Front 63

Blood Agar test results

Back 63

a-Hemolysis (alpha)= partial breakdown, green

y-Hemolysis (gamma)= no break down

B-Hemolysis (beta)= complete breakdown, clear

Front 64

B-HEMOLYSIS

Back 64

Clear

Front 65

a-Hemolysis

Back 65

Green

Front 66

y-Hemolysis

Back 66

No breakdown

Front 67

Coagulase and Clumping Factor tests

Back 67

Coagulase tube test

Remains liquid- coagulase (-)

Solid- coagulase (+)

Same for slide

Front 68

Enterotube ll

Back 68

Multitest system designed to identify enteric bacteria and other select oxidase-negative, Gram-neg bacteria

Front 69

Standard plate count (viable plate)

Urine plate

Yellow loop, blue loop

Back 69

Yellow loop= 10 microliter, .01

Blue loop= 1 microliters, .001

Front 70

Standard plate calculation

Back 70

OCD= CFU/loop volume

Make sure u put CFU's/ml at end

CFU= # counting

OCD= # looking for

Front 71

Urinary tract infections results

Back 71

*Greater than or = to 100,000 CFU's/ml is UTI

*greater than or = to 10,000 to less than 100,000 CFU's/ml is possible UTI

*less than 10,000 CFU's/ml is contamination (specimen collected or handled improperly)

Front 72

Antimicrobial susceptibility test: disk diffusion (kirby-Bauer) method

Back 72

Measure green circle in mm counting smallest lines

Front 73

The Enterotube ll is inoculated using

Back 73

A plated colony

Front 74

What is the Kirby-Bauer test

Back 74

It tests the susceptibility of microorganisms to antimicrobial agents

Front 75

Which test utilizes iodine reagent

Back 75

Starch

Front 76

Which of the following tests for amonia production

Back 76

Urea

Front 77

Clotted plasma is a (+) result for which test

Back 77

Coagulase

Front 78

Which test uses semisoft agar

Back 78

SIM

Front 79

The coagulase test is used to identify which species

Back 79

Staphylococcus

Front 80

What reagent is added to the SIM tube for the Indole test

Back 80

Kovac's Reagent

Front 81

Utilization media are designed to test the ability of an organism to

Back 81

Grow in the presence of a single essential nutrient

Front 82

The pH indicator bromthymol blue is used in the

Back 82

Simmons Citrate Agar test

Front 83

The purpose of the bile salts in the Bile Esculin Azide Agar is to

Back 83

Inhibit the growth of gram (+) organisms

Front 84

Bile Esculin Agar pic

Back 84

Left is bile esculin (+)