SF I Lab: Gram Neg

Question 1

Used primarily to differentiate members of Enterobacteriaceae family from other GN rods

Answer 1

Triple Sugar Iron

Question 2

Indicator of Hydrogen Sulfide

Answer 2

Ferric Ammonium Citrate

Question 3

Expected Result: lactose and glucose fermenter

Answer 3

A/A (Acid slant/ Acid Butt)

Question 4

Reporting for Non lactose fermenter but glucose fermenter and H2s positive

Answer 4

K/A H2s+

Question 5

How many hours do we incubate the TSI tube in ambient air?

Answer 5

18-24 hours

Question 6

Ph indicator for TSI

Answer 6

Phenol red

Question 7

Used to differentiate Gram negative bacteria on the deaminatio of phenylalanine

Answer 7

Phenylalanine Deaminase Agar

Question 8

Reagent for Phenylalanine Deaminase Agar

Answer 8

10% Ferric Chloride (FeCl3)

Question 9

Product for Phenylalanine Deaminase Agar

Answer 9

Green Color

Question 10

How many drop(s) of 24 hour BHI broth do we add to inoculate phenylalanine?

Answer 10

1 drop

Question 11

Used to differentiatw Gram negative bacilli based on the decarboxylation or deaminatio of lysine and H2s production

Answer 11

Lysine Iron Agar

Question 12

pH Indicator for LIA

Answer 12

Bromcresol purple

Question 13

Amino acid source for LIA

Answer 13

L-lysine

Question 14

Product for Lysine Deamination

Answer 14

Burgundy/ Bordeaux Red Color

Question 15

Enzyme for LIA

Answer 15

Lysine Deaminase

Question 16

Substrate for LIA

Answer 16

Lysine

Question 17

Lysine decarboxylation positive reaction

Answer 17

Purple Color

Question 18

Product for Lysine Decarboxylation

Answer 18

CO2 + Cadaverine

Question 19

Deaminase negative color

Answer 19

Purple

Question 20

Decarboxylase negative color

Answer 20

Yellow

Question 21

Detects the presence of tryptophanase

Answer 21

Indole Test

Question 22

Reagent use for indole test

Answer 22

dimethylamine-benzaldehyde

Question 23

Product for Indole test

Answer 23

Triarylmethane Dye (Red)

Question 24

Rapid/Spot indole test reagent

Answer 24

Paradimethylamino-cinnamaldehyde

Question 25

Detects the presence of glucose metabolic by products via the mixed acid fermentation pathway

Answer 25

Methyl Red Test

Question 26

Number of methyl red drops use per 5 ml of Methyl red broth

Answer 26

5 or 6

Question 27

Detects thw presence of glucose metabolic by products via butylene glycol pathway

Answer 27

Voges-Proskauer Test

Question 28

Reagent use for Voges-Proskauer Test

Answer 28

Potassium hydroxise (KOH) & a-naphthol

Question 29

Number of drops of alpha-naphthol use for VP broth

Answer 29

6 drops

Question 30

Number of minutes VP broth should be incubated for the second time after shaking the tube

Answer 30

30 minutes

Question 31

Determines whether an organism can utilize citrate as the sole carbon source and inorganic ammonium salta as the sole nitrogen source

Answer 31

Citrate Utilization

Question 32

pH indicator of Citrate utilization test

Answer 32

Bromthymol blue

Question 33

Positive reaction of Citrate utilization test

Answer 33

Prussian blue

Question 34

Negative reaction for Citrate utilization test

Answer 34

Green

Question 35

This test is used to determine the ability of an organism to reduce nitrate to nitrite

Answer 35

Nitrate reduction

Question 36

True negative reaction of Nitrate reduction test

Answer 36

Nitrate + Zinc powder = Nitrate ( reacts with reacts with reagent to form red dye)

Question 37

Reagent for Nitrate reduction

Answer 37

Sulfanilic acid + alpha-naphthylamine

Question 38

False negative reaction of Nitrate reduction

Answer 38

Organisms reduced it further to NH3, NO, or N2O2

Question 39

Tube use for nitrate reduction test to identify gas production

Answer 39

Durham tube

Question 40

Substrate for ONPG test

Answer 40

O-nitrophenyl-b-D-Galactopyranoside

Question 41

ONPG test product

Answer 41

Ortho-nitrophenol

Question 42

Positive reaction for ONPG test

Answer 42

Yellow

Question 43

Test is used to determine an organism's ability to produce the enzyme urease, which hydrolyzes urea

Answer 43

Urease Test (Christensen's Method)

Question 44

Positive reaction for urease test

Answer 44

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