Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Clinical Bacteriology (Finals) > (Laboratory) Identification of Enterobacteriaceae > Flashcards

(Laboratory) Identification of Enterobacteriaceae Flashcards

1
Q

List down the step-by-step procedure in EMB, SSA and HEA Inoculation:

A
  1. Using a sterile swab, obtain a small amount of stool specimen and use it to make the first streaks in your first quadrant.
  2. Change into a sterilized loop and continue streaking to the second, third, and fourth quadrant.
  3. Incubate overnight. Observe the colonial morphology.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

List down the step-by-step procedure in the Gram Staining of Enterobacteriaceae:

A
  1. Prepare a smear from the bacterial source.
  2. Air dry and proceed with the staining.
  3. Observe microscopic morphology under the microscope.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

List down the step-by-step procedure in the MacConkey Inoculation:

A
  1. Inoculate bacteria from the source plate into the MacConkey agar.
  2. Incubate overnight. Observe the colonial morphology.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

List down the step-by-step procedure in TSI for Enterobacteriaceae:

A
  1. Sterilize your inoculating needle and pick an isolated colony from your source plate.
  2. Observe aseptic techniques. Stab the butt portion of the media and continue making serpentine motion on the slant portion.
  3. Incubate overnight. Interpret based on color reaction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List down the step-by-step procedure in SCA for Enterobacteriaceae:

A
  1. Sterilize your inoculating needle and pick an isolated colony from your source plate.
  2. Observe aseptic techniques. Stab the butt portion of the media and continue making serpentine motion on the slant portion.
  3. Incubate overnight. Interpret based on color reaction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

List down the step-by-step procedure in SIM for Enterobacteriaceae:

A
  1. Sterilize your inoculating needle and pick an isolated colony from your source plate.
  2. Observe aseptic techniques. Stab the butt portion of the media as straight as possible. Remove the inoculating needle as straight as possible.
  3. Incubate overnight.
  4. After incubation, interpret the motility and H2S production.
  5. Add a few drops (3-5 drops) of Kovac’s reagent and interpret indole production.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

List down the step-by-step procedure in Methyl Red Test:

A
  1. Sterilize your inoculating loop and pick an isolated colony from your source plate.
  2. Observe aseptic techniques. Inoculate the bacteria into the broth.
  3. Incubate overnight
  4. Divide the broth into two separate tubes. Label the tube “MR.”
  5. In the tube labelled MR, add 5 drops of methyl red reagent.
  6. Observe for changes in color.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How many drops of methyl red reagent is added in the slide for the Methyl Red Test?

A

5 drops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the color of the positive result of the Methyl Red Test?

A

Red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the color of the negative result of the Methyl Red Test?

A

Yellow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

List down the step-by-step procedure in Voges Proskauer Test:

A
  1. Sterilize your inoculating loop and pick an isolated colony from your source plate.
  2. Observe aseptic techniques. Inoculate the bacteria into the broth.
  3. Incubate overnight
  4. Divide the broth into two separate tubes. Label the tube “VP.”
  5. In the tube labelled VP, add 6 drops of alpha naphthol reagent and mix well to aerate.
  6. Add 2 drops of KOH reagent and mix well to aerate.
  7. Shake well.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How many drops of alpha naphthol is added on the slide for Voges Proskauer Test?

A

6 Drops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How many drops of KOH is added on the slide for Voges Proskauer Test?

A

2 Drops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the color of the positive result of the Voges Proskauer Test?

A

Red Color

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the color of the negative result of the Voges Proskauer Test?

A

Chocolate brown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

List down the step-by-step procedure in SCA for Enterobacteriaceae:

A
  1. Sterilize your inoculating needle and pick an isolated colony from your source plate. Make sure to get only a small portion of the bacterial growth. Do not take too much.
  2. Observe aseptic techniques. Inoculate the surface of the slant with serpentine motion.
  3. Incubate overnight.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Composition of TSI:

A

1% lactose
1% sucrose
0.1% glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

This is added to TSI tubes to detect the production of hydrogen sulfide H2S (black precipitate in the medium)

A

Ferrous sulfate
Sodium thiosulfate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

pH Indicator of TSI

A

Phenol red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Original color of the medium of TSI

A

Red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

A similar medium to TSI but only incorporates the carbohydrates glucose and lactose.

A

Kligler’s Iron Agar (KIA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Both TSI and KIA or the kligler’s iron agar are poured on a slant. The slant portion is (aerobic or anaerobic) and the butt or deep portion is (aerobic or anaerobic).

A

Aerobic
Anaerobic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

In TSI, phenol red is used as the pH indicator which is yellow below the pH of _____

A

6.8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

In TSI, An inoculated medium is red, because the pH is buffered at _____

A

7.4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the TSI result if there is no fermentation that happened?

A
  • Alkaline slant/alkaline butt (ALK/ALK or K/K) or alkaline slant/no change (ALK/no change or K/NC)
  • Red/Red
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the TSI result if there is glucose fermentation only but no lactose or sucrose?

A
  • Alkaline slant/acid butt (K/A)
  • Red/Yellow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the TSI result if there is lactose (or sucrose or both) fermentation?

A
  • Acid/acid (A/A)
  • Yellow/Yellow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the TSI result if there is H2S production?

A
  • Blackening of the medium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the TSI result if there is Gas production (aerogenic) or no gas production (nonaerogenic)?

A
  • Formation of bubbles or splitting of the medium from the bottom of the tube
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

IMViC means:

A

● Indole Test
● Methyl Red Test
● Voges-Proskauer Test
● Citrate Utilization Test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Test the ability of the bacteria to produce the enzyme tryptophanase and deaminate tryptophan to indole, pyruvic acid, and ammonia.

A

Indole Test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What media is used to test for indole?

A

Sulfide Indole Motility (SIM)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

An amino acid that acts as a substrate in the Indole Test?

A

Tryptophan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Production of indole is detected using:

A

Ehrlich’s Reagent
Kovac’s Reagent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Positive result of Indole Test

A

Pink/Red Ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the negative reaction in the Methyl Red Test?

A

Remain yellow after addition of MR pH indicator

37
Q

What is the positive reaction in the Methyl Red Test?

A

Red color after addition of MR pH indicator

38
Q

Media used for Methyl Red Test?

A

MRVP Medium

39
Q

Reagent in Methyl Red Test

A

Methyl Red

40
Q

A test that detects the production of acetoin after the addition of α-naphthol (catalyst or color intensifier) followed by 40% KOH or NaOH

A

Voges Proskauer Test

41
Q

Positive reaction in the Voges Proskauer Test

A

Red complex

42
Q

Catalyst or color intensifier of the Voges Proskauer Test

A

Alphanapthol

43
Q

Reagent used in the Voges Proskauer Test

A

Alphanapthol and 40% KOH/NaOH

44
Q

A test that determines whether an organism can use sodium citrate as a sole carbon source

A

Citrate Utilization Test

45
Q

A routinely used medium in the Citrate Utilization Test

A

Simmon’s Citrate Medium (SCA)

46
Q

_____ are the nitrogen source in the Simmon’s Citrate Medium and utilization of these results in the release of ammonia, causing a pH change

A

Ammonium Salts

47
Q

pH indicator in the Cirate Utilization Test

A

Bromothymol Blue

48
Q

Positive reaction in the Citrate Utilization Test

49
Q

Negative reaction in the Citrate Utilization Test

50
Q

A test that determines whether an organism has the ability to reduce nitrate to nitrite

A

Nitrate Reduction Test

51
Q

Reagent in the Nitrate Reduction Test

A

N,N-Dimethyl-α-naphthylamine
Sulfanilic acid

52
Q

Positive reaction of the Nitrate Reduction Test

A

Red color (Diazo Red Dye)

53
Q

Nitrate reduction test is a test that determines the production of an enzyme called _____ which results in the reduction of nitrate into nitrite.

A

Nitrate reductase

54
Q

A test that determines the presence of the cytochrome oxidase system that oxidizes reduced cytochrome with molecular oxygen

A

Oxidase Test

55
Q

Oxidase Test differentiates _____ which are oxidase-negative from _____ which are oxidase-positive

A

Enterobacteriaceae
Pseudomonas

56
Q

Enterobacteriaceae are oxidase (positive or negative).

A

Oxidase negative

57
Q

Pseudomonas are oxidase (positive or negative).

A

Oxidase positive

58
Q

Reagent in the Oxidase Test

A

Tetramethyl-p-phenylenediamine dihydrochloride

59
Q

Positive reaction of Oxidase Test

A

Purple or Lavender Color

60
Q

An enzyme that is important in the electron transport chain

A

Cytochrome C Oxidase

61
Q

A test that determines whether a microorganism can hydrolyze urea (by the action of urease enzyme), releasing a sufficient amount of ammonia to produce a color change by a pH indicator

A

Urease Test

62
Q

Preferred medium for the Urease Test

A

Christensen’s Urea Agar

63
Q

pH indicator for Urease Test

A

Phenol red

64
Q

Positive reaction of the Urease Test

A

Bright pink color

65
Q

The substrate in the Urease Test

66
Q

Gelatin hydrolysis test is also known as the _____

A

Gelatin Liquefaction Test

67
Q

Positive result of the Gelatin Hydrolysis Test

A

Liquefaction

68
Q

Media demonstrate the production of H2S:

A
  • Sulfide-indole-motility agar
  • Motility-indole-ornithine agar
  • Hektoen Enteric agar
  • Salmonella-Shigella agar
  • Triple Sugar Iron agar
  • Kligler Iron agar
  • Lysine Iron agar
69
Q

SIM medium contains _____ which serves as an indicator for the production of hydrogen sulfide.

A

Ferrous sulfate

70
Q

Production of hydrogen sulfide can be detected when _____, a black precipitate is produced as a result of ferrous sulfate reacting with hydrogen sulfide gas.

A

Ferrous sulfide

71
Q

What is the agar concentration in the Motility Testing?

72
Q

Routine medium used in Motility Testing

A

Sulfide Indole Motility Agar (SIM)

73
Q

Positive reaction of the Motility Test

A

Movement away the stab line or hazy appearance throughout the medium

74
Q

Two amino acids commonly used to test for decarboxylase activity:

A

Lysine
Ornithine

75
Q

Products of Decarboxylation

A

Amine or Diamine Molecules
CO2

76
Q

Positive reaction for the Decarboxylase and Dihydrolase Test

A

Purple Color

77
Q

Negative reaction for the Decarboxylase and Dihydrolase Test

A

Yellow Color

78
Q

Reagent used in the Phenylalanine Deaminase Test

A

10% Ferric chloride

79
Q

Positive reaction of the Phenylalanine Deaminase Test

A

Green Color

80
Q

Species that are Phenylalanine Deaminase positive

A

Proteus
Morganella
Providencia

81
Q

This is used primarily to determine whether the bacteria Decarboxylate or Deaminate lysine.

A

Lysine Iron Agar Slant

82
Q

Salmonella spp. are lysine (positive or negative)

A

Lysine Positive

83
Q

Citrobacter spp. are lysine (positive or negative)

A

Lysine Negative

84
Q

Lysine Iron Agar Slant contains:

A

Amino acid lysine
Glucose
Ferric ammonium citrate
Sodium thiosulfate

85
Q

pH indicator in the Lysine Iron Agar Slant

A

Bromocresol purple

86
Q

Lysine Decarboxylation positive result

A
  • Purple slant/purple butt (alkaline)
  • K/K
87
Q

Lysine Decarboxylation negative result

A
  • Purple slant/yellow butt (acid), fermentation of glucose only
  • K/A or R/A
88
Q

Lysine Deamination positive result

A
  • Red slant
  • R/A
89
Q

Lysine Deamination negative result

A
  • Slant remains purple
  • K/K or K/A

Clinical Bacteriology (Finals) (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions