Brainscape's Knowledge GenomeTM

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


See full index

Bacteriology Lecture > Lesson 10: The Enterobacteriaceae > Flashcards

Lesson 10: The Enterobacteriaceae Flashcards

1
Q

Bacteria found in the Family Enterobacteriaceae (ESSEPY)

A

Escherichia
Shigella
Salmonella
Enterobacter
Proteus
Yersinia

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

Enterobacteriaceae are:

Gram-negative
Short rods
Non-sporulating
Facultative anaerobes

A

True

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

It is an agar used to isolate and differentiate organisms of Enterobacteriaceae family

A

MacConkey agar

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

MacConkey agar differentiates lactose fermenter coliforms from Non-lactose fermenters by what colors?

A

Lactose fermenter: Pink colored
Non-Lactose fermenter: Pale colored

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

Lactose Fermenters (CEEK)

A

Citrobacter
Escherichia
Enterobacter
Klebsiella

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

Are enterobacteriaceae Cytochrome C oxidase negative or positive?

A

Cytochrome C oxidase negative (-)

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

Non-Lactose Fermenters (ShYPS)

A

Shigella
Yersinia
Proteus
Salmonella

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

Are enterobacteriaceae catalase positive or negative?

A

Catalase positive (+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Non-Lactose Fermenters
Nonmotile and Non-H2S producing

A

Shigella
Yersinia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Non-Lactose Fermenters
Motile and H2S producing

A

Proteus
Salmonella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

True or False

Pseudomonas and other oxidase positive bacteria reduce NITRATE to NITROGEN GAS

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

True or False

Enteric bacteria usually reduces NITRATE to NITRITE

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Oxidase positive bacteria (PAVAAFC)

A

Pseudomonas
Aeromonas
Vibrio
Alcaligenes
Achromobacter
Flavibacterium
Cardiobacterium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Characteristic antigen of Enterobacteriaceae

A

Enterobacterial Common Antigen

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

4 Enterobacterial Common Antigens

A

O: Outer membrane
H: Flagella
K: Capsule
Vi: Capsule of Salmonella

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

Does enterobacteriaceae produce acid from glucose and have the ability to ferment lactose?

A

Yes

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

Biochemical Tests to Identify Enterobacteriaceae family

A

IMVC Test
Motility Test
Triple Sugar Iron (TSI) Agar Test
Urease Test

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

It is a test used to determine the ability of bacteria to utilize sodium citrate as a carbon source and inorganic ammonium dihydrogen phosphate (NH4H2PO4) as the sole fixed nitrogen source

A

Citrate Utilization Test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Citrate medium most commonly used in the citrate utilization test is?

A

Formula of Simmons

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

Utilization of exogenous citrate requires the presence of citrate transport proteins known as?

A

Permeases

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

Upon uptake by the cell, citrate is cleaved by citrate lyase into?

A

Oxaloacetate and acetate

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

Oxaloacetate is metabolized into?

A

Pyruvate and CO2

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

Citrate Test: POSITIVE (SPPECKS)

A

Serratia marcescens
Providencia
Proteus mirabilis
Enterobacter spp.
Citrobacter freundii
Klebsiella pneumoniae
Salmonella (other than Typhi and Parathypi A)

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

Under alkaline conditions, pyruvate is metabolized to?

A

Acetate and formate

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

At pH 7.0 and below, pyruvate is metabolized to?

A

Acetate + Lactate + CO2

or

Acetoin + CO2

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

Growth in Citrate Utilization Test results in the bromothymol blue indicator, turning from ______ to ______

A

Green to Blue

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

Bromothymol blue pH indicate has a color of what at neutral pH?

A

Forest green

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

An increase in medium pH to above 7.6, bromothymol blue changes to ____

A

blue

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

Positive result/Color in Citrate Utilization Test

A

Intense Prussian blue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Citrate Test: VARIABLE (PVV)

A

Proteus vulgaris
Vibrio cholerae
Vibrio parahaemolyticus

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

Citrate Test: NEGATIVE (SMESSY)

A

Shigella spp.
Morganella morganii
Escherichia coli
Salmonella Typhi
Salmonella Paratyphi A
Yersinia enterocolitica

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

4(p)-dimethylaminobenzaldehyde reacts with indole to produce what colored compound?

A

Red-colored compound

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

It is a test used to determine the ability of an organism to split amino acid TRYPTOPHAN

A

Indole Test

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

Tryptophan is hydrolyzed by this enzyme to produce 3 possible end products, one of which is Indole.

A

Tryptophanase

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

Indole production is detected by what reagents?

A

Kovac’s or Ehrlich’s reagent

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

This is found in Kovac’s or Ehrlich’s reagent that reacts with Indole to produce a “Red-colored” compound

A

4(p)-dimethylaminobenzaldehyde

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

Two methods used in Indole Test

A

Conventional Tube Method
Spot Indole Test (detects rapid indole producing organisms)

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

In the Conventional Tube Method for Indole Test, how much Kovac’s reagent is added to the broth culture?

A

0.5 mL of Kovac’s reagent

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

Results of Conventional Tube Method for Indole Test

Positive:
Negative:

A

Positive: Pink colored ring
Negative: No color change (E.g. Klebsiella pneumoniae)

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

It is a type of Indole Test used to determine the presence of the enzyme tryptophanase

A

Spot Indole Test

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

In the Spot Indole Test, the piece of filter paper is saturated with?

A

1% para-dimethylaminocinnamaldehyde reagent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

In the Spot Indole Test, when tryptophan releases indole and reacts with “cinnamaldehyde”, it produces what color compound?

A

Blue-green compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Spot Indole Test Results:

Positive:
Negative:

A

Positive: Blue Color within 30 seconds
Negative: No color change / Slightly Pink color

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Indole: POSITIVE (PEMP)

A

E. coli
P. vulgaris
M. morganii
Providencia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Klebsiella species: (Indole Test)

Positive:
Negative:

A

Positive: K. oxytoca
Negative: K. pneumoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Citrobacter spp: (Indole Test)

Positive:
Negative:

A

Positive: C. koseri
Negative: C. freundii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Proteus spp: (Indole Test)

Positive:
Negative:

A

Positive: P. vulgaris
Negative: p. mirabilis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Indole Positive for Klebsiella, Citrobacter, and Proteus spp. (OKVIP)

A

klebsiella Oxytoca
citrobacter Koseri
proteus Vulgaris

Indole Positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

3 commonly used agar for Indole Test (SIM, MIU, MIO)

A

Sulfide-indole-motility medium (SIM)
Motility-indole-urease medium (MIU)
Motility-indole-ornithine medium (MIO)

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

What is the most accurate way to determine bacterial motility?

A

Microscopy

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

This method is a commonly used microscopic technique to check the motility test

A

Hanging drop method

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

Non-motile, gram-positive cocci, enterococci (2)

A

E. faecium
E. faecalis

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

Motile, gram-positive cocci, enterococci (2)

A

E. gallinarum
E. casseliflavus/E. flavescens

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

A test to differentiate:

Vibrio species (gram-negative motile curved rod)
Aeromonas species (gram-negative motile rod)

A

Distilled water motility test

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

Aeromonas species will grow on MacConkey agar and sometimes on Thiosulfate-Citrate-Bile Salts-Sucrose agar, producing what colony color?

A

Yellow colonies

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

Methyl Red Results:

Positive:
Negative:

A

Positive: Red after addition of MR, pH at or below 4.4 from fermentation of glucose

Negative: Yellow after addition of MR, pH above 5.1 from the fermentation of glucose

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

True or False

Vibrio species and Aeromonas species are oxidase positive (+)

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Result of Distilled Water Motility Test for Vibrio and Aeromonas spp

A

Vibrio: immobilized on distilled water and motile on peptone water

Aeromonas: motile in both distilled and peptone water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

A test that determines whether the microbe performs mixed acids fermentation when supplied glucose

A

Methyl Red (MR) Test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What color is methyl red above pH 5.1 and at pH 4.4?

A

above 5.1 = yellow
at 4.4 = red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Methyl Red (MR): POSITIVE (PYCESS)

A

Proteus spp.
Yersinia spp.
Citrobacter spp.
Escherichia coli
Shigella spp.
Salmonella spp.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

In Methyl Red test, does an intermediate ORANGE color between yellow and red indicate a positive test?

A

No, it does not.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

MR Test Positive: E.coli appearance

A

E. coli = red color appearance after addition of methyl red reagent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

MR Test Negative: K. aerogenes appearance

A

K. aerogenes = lack of color change after addition of methyl red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Methyl Red (MR): Negative (SHEK)

A

Serratia marcescens
Hafnia spp.
Enterobacter spp.
Klebsiella pneumoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

It is a test first observed the “RED” color reaction produced by appropriate culture media after treatment with potassium hydroxide. It was later discovered that the active product in the medium formed by bacterial metabolism is acetyl methyl carbinol, a product of the butylene’s glycol pathway

A

Voges-Proskauer Test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Members of Klebsiella-Enterobacter-Hafnia-Serratia group produce this as the chief end product of glucose metabolism

A

Acetoin (acetyl methyl carbinol)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

In the presence of atmospheric oxygen and 40% potassium hydroxide, acetoin is converted diacetyl, and __________ serves as a catalyst to bring out a RED COMPLEX

A

alpha-naphthol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Voges-Proskauer Test Result

Positive:
Negative:

A

Positive: Red color at 15 minutes or more after the addition of the reagents indicating the presence of diacetyl, the oxidation product of acetoin

Negative: Copper like color (over 1 hour)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

In Triple Sugar Iron Agar (TSI), what are the 3 sugar present?

A

Lactose
Sucrose
Glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

TSI is a semi-solid media which means that?

A

It has both a slant and a butt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Concentration of Lactose, Sucrose, Glucose in TSI respectively?

A

10:10:1

or

1% : 1% : 0.1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

TSI is similar to Kligler’s iron agar (KIA) except that?

A

KIA has only 2 carbohydrates which is glucose and lactose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Interpretation of Triple Sugar Iron Agar Test:

*If lactose is not fermented but a small amount of glucose is

A

The oxygen-deficient butt: YELLOW
The less acidic slant: RED

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Expected results of TSI Agar test:

Alkaline slant/no change in butt (K/NC)
Alkaline slant/Alkaline butt (K/K)
Alkaline slant/Acidic butt (K/A)
Acidic slant/Acidic butt (A/A)

A

(K/NC) Red/Red = glucose, lactose and sucrose non-fermenter

(K/K) Red/Red = glucose, lactose and sucrose non-fermenter

(K/A) Red/Yellow = glucose fermentation only, gas (+ or -), H2S (+or -)

(A/A) Yellow/Yellow = glucose, lactose and/or sucrose fermenter gas (+ or -), H2S (+ or -).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Phenol red in TSI is what color in acidic and in alkaline conditions?

A

Acidic: Yellow
Alkaline: Red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

In the TSI agar, what is the indicator of acidification?

A

Phenol red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Interpretation of Triple Sugar Iron Agar Test:

*If lactose (or sucrose) is fermented

A

A large amount of acid is produced and turns the phenol red indicator YELLOW both in the butt and slant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Interpretation of Triple Sugar Iron Agar Test:

*If neither lactose/sucrose nor glucose is fermented

A

Both butt and slant: RED

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Reaction of the organisms in the TSI: Salmonella, Proteus

Slant:
Butt:
Gas:
H2S:

A

Slant: Alkaline (K)
Butt: Acid (A)
Gas: Positive (+)
H2S: Positive (+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Reaction of the organisms in the TSI: Pseudomonas

Slant:
Butt:
Gas:
H2S:

A

Slant: Alkaline (K)
Butt: Alkaline (K)
Gas: Negative (-)
H2S: Negative (-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Reaction of the organisms in the TSI: Escherichia, Klebsiella, Enterobacter

Slant:
Butt:
Gas:
H2S:

A

Slant: Acid (A)
Butt: Acid (A)
Gas: Positive (+)
H2S: Negative (-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Interpretation of Triple Sugar Iron Agar Test:

*If H2S is produced

A

Black color of ferrous sulfide is seen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Reaction of the organisms in the TSI: Shigella, Serratia

Slant:
Butt:
Gas:
H2S:

A

Slant: Alkaline (K)
Butt: Acid (A)
Gas: Negative (-)
H2S: Negative (-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

2 Medium used for Urease Test

Agar:
Broth:

A

Agar: Christensen’s Urea Agar (CUA)
Broth: Stuart’s Urea Broth (SUB)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is the indicator used in Urease Test?

A

Phenol Red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

UREASE TEST: Color change

Non-producer of urease enzyme

A

Slant and Butt remain LIGHT ORANGE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Which organisms in the urease test will hydrolyze urea RAPIDLY?

(within 1 or 6 hours of incubation)(ProProMo)

A

Proteus spp.
Morganella morganii
Providencia stuartii strains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

In the urease test principle, when urease splits urea in the presence of water to release ammonia and carbon dioxide, the ammonia combines with carbon dioxide and water to form ammonium carbonate which turns the medium alkaline, this will turn the indicator phenol red from its original organ yellow color to?

A

Bright pink

Note: When the medium turns alkaline, phenol red will convert from yellow to PINK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Urease test results in routine diagnostic laboratories are read within how many hours?

A

Within 24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Which organisms in the urease test will have a DELAYED POSITIVE?

(6 hours of incubation which will be intense during further incubation) (EnKle)

A

Enterobacter spp.
Klebsiella spp.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Which organisms in the urease test will have a NEGATIVE result?

(Remain a YELLOWISH color)

A

Escherichia coli.

52
Q

Humans are most likely to be infected with what strain of E. coli?

A

E. coli O157:H7

53
Q

Urease positive organisms (PUNCH)

A

Proteus
Ureaplasma
Nocardia
Cryptococcus neoformans/Corynebacterium spp.
Helicobacter pylori

54
Q

Diagnostic utility of Urease Test: Explain

  1. Proteus spp. and Enterobacteriaceae
  2. Helicobacter pylori and tissue biopsy material
  3. Cryptococcus neoformans and Candida albicans
  4. Urea breath test: Helicobacter pylori
A
  1. Proteus spp. which is urease positive is differentiated from Enterobacteriaceae family which are non-lactose fermenting
  2. Crushed tissue biopsy is placed into urease broth and if it is positive, there is the presence of Helicobacter pylori
  3. Cryptococcus neoformans is a rapid urease producer while Candida albicans are not
  4. Presence of Helicobacter pylori based on urease activity, highly sensitive and specific
54
Q

UREASE TEST: Color change

Urease enzyme producer

A

Slant changes from LIGHT ORANGE to MAGENTA

55
Q

Urease positive bacteria (PCCHB)

A

Proteus
Cryptococcus
Corynebacterium
Helicobacter pylori
Brucella

56
Q

Who discovered E. coli after isolating it from the feces of newborns?

A

Theodor Escherich

56
Q

Where is the primary habitat of E.coli?

A

Gastrointestinal tract (GIT)

56
Q

It is the largest group of bacteria living in the intestine

A

E. coli

57
Q

E. coli helps with the absorption of what nutrients in the colon?

A

Vitamin K and other vitamins

58
Q

Gram stain of E. coli?

A

Gram-negative bacilli

59
Q

What is the TYPE of E.coli that is fimbriated and are present in both motile and non-motile strains.

A

Type 1 (hemagglutinating & mannose-sensitive)

60
Q

What is the major cell wall antigen of E. coli?

A

Heat Stable LPS

61
Q

What antigen of E. coli is:

“Flagellar Antigen”
Heat and alcohol labile (non-resistant)
Monophasic

A

H antigen

62
Q

What antigen of E. coli is:

“Somatic Antigen”
Heat stable, resistant to boiling up to 2 hours and 30 mins
Surface of the Outer Membrane

A

O antigen

63
Q

What antigen of E. coli is:

“Capsular Antigen”
Heat labile
Acidic polysaccharide antigen present in the envelope
Inhibits “phagocytosis”

A

K antigen

64
Q

How can K antigen be removed?

A

By boiling

65
Q

What antigen of E. coli is:

“Fimbrial Antigen”
Heat labile (non-resistant)
Present in the Fimbriae

A

F antigen

66
Q

Identify if Nutrient Agar, Blood Agar, MacConkey Agar, EMB Agar, m-ENDO Agar, or Liquid Media for E.coli

“Large, circular, low convex”
Grayish, White
Moist
Smooth and Opaque
2 forms: Smooth and Rough form

A

Nutrient Agar (NA)

67
Q

What form of E. coli is emulsifiable in saline?

A

Smooth form

68
Q

What causes E. coli to have S-R variation?

A

Repeated subculture

69
Q

Identify if Nutrient Agar, Blood Agar, MacConkey Agar, EMB Agar, m-ENDO Agar, or Liquid Media for E.coli

“Big, circular”
Gray
Moist
Beta hemolytic

A

Blood Agar (BA)

70
Q

Identify if Nutrient Agar, Blood Agar, MacConkey Agar, EMB Agar, m-ENDO Agar, or Liquid Media for E.coli

“Green Metallic Sheen”

A

Eosin Methylene Blue (EMB) Agar

70
Q

What type of hemolysis do E. coli form on Blood Agar?

A

Beta hemolysis

71
Q

Identify if Nutrient Agar, Blood Agar, MacConkey Agar, EMB Agar, m-ENDO Agar, or Liquid Media for E.coli

“Circular”
Moist, smooth and of entire margin
Flat and Pink colonies
Lactose fermenting colonies

A

MacConkeye Agar (MAC)

72
Q

What does CFA mean for E. coli?

A

Colonization factor antigen

72
Q

True or False

Most infections of E. coli are endogenous except for neonatal meningitis and gastroenteritis

A

True

72
Q

Identify if Nutrient Agar, Blood Agar, MacConkey Agar, EMB Agar, m-ENDO Agar, or Liquid Media for E.coli

“Green Metallic Sheen”
Metabolize lactose with the production of “Aldehyde and Acid”

A

m-ENDO Agar

72
Q

Identify the E. coli pathotype (ETEC, EPEC, EHEC, EIEC, EAEC, DAEC)

“common cause of bacterial diarrheal disease”
“acute watery diarrhea in infants and adults”
“Pathogenesis: attachment to intestinal mucosa mediated by fimbrial protein called CFA” and elaboration of heat-stable and heat-labile enterotoxins”
“No person to person contamination”

A

ETEC (Enterotoxigenic E. coli)

72
Q

Identify if Nutrient Agar, Blood Agar, MacConkey Agar, EMB Agar, m-ENDO Agar, or Liquid Media for E.coli

“Homogenous turbid growth within 12-18 hours”
Rough (R) form agglutinate spontaneously
Sediment on bottom of test tube
Pellicle formed on the surface (>72 hours)
Heavy deposits are formed which disperses on shaking

A

Liquid Media

72
Q

Identify the Biochemical properties of E. coli

IMVC:
Urease:
Motility:
Catalase:
Carbohydrate fermentation:

A

IMVC: Indole and Methyl Red Positive
IMVC: Voges-Proskauer and Citrate Negative
Urease: Negative (-)
Motility: Positive (+)
Catalase: Negative (-)
Carbohydrate fermentation: Positive (+)

73
Q

Identify the E. coli pathotype (ETEC, EPEC, EHEC, EIEC, EAEC, DAEC)

“Frequently causes infantile diarrhea and occasionally causes sporadic diarrhea in adults”
“non-toxigenic and non-invasive”
“Person to person spread is seen”
“Attachment to intestinal mucosa is through cup-like projections called pedestals”

A

Enteropathogenic E. coli (EPEC)

73
Q

2 Classes of Enterotoxins produced by ETEC

A

Heat-stable toxins (STa and STb)
Heat-labile toxins (LT-I and LT-II)

73
Q

What heat-stable toxin of ETEC is associated with human disease?

A

STa

73
Q

What are the 2 groups of E. coli that cause enteric disease?

A

Enteropathogenic E. coli (EPEC)
Shiga toxin-producing E. coli (STEC)

73
Q

Cluster of virulence genes of EPEC and STEC are located on a chromosomal pathogenicity island called?

A

Locus of enterocyte effacement (LEE)

74
Q

These are produced on the intestinal epithelium coded by LEE gene which leads to the DISRUPTION of brush border epithelium causing increased secretion and watery diarrhea

A

A/E Lesions (Attaching and Effacing lesions)

75
Q

Identify the E. coli pathotype (ETEC, EPEC, EHEC, EIEC, EAEC, DAEC)

“These are heterogenous collection of strains characterized by their autoagglutination in a ‘stacked-brick’ arrangement over the epithelium of the small intestine and in the colon”
“These are one of the few bacteria associated with Chronic Diarrhea and growth retardation in children”

A

Enteroaggregative E. coli (EAEC)

75
Q

Most strains of EAEC are ___ untypeable but ___ typeable

A

O = untypeable
H = typeable

76
Q

True or False

For EHEC, ingestion of FEWER than 100 bacteria can produce disease and spread person-to-person?

A

True

76
Q

EAEC adheres to what cells that form a “stacked-brick” fashion?

A

HEP-2 cells (Human epidermal cells)

77
Q

What are the other names of Enterohemorrhagic E. coli?

A

Verocytotoxin-producing E. coli (VTEC)
Shiga toxin-producing E. coli (STEC)

77
Q

2 types of Shiga toxin produced by EHEC/VTEC/STEC?

A

Stx1 (Shiga toxin 1)
Stx2 (Shiga toxin 2)

77
Q

This strain of enteroaggregative strain has caused major outbreaks in Germany.

Produces a “Shiga-like toxin and can cause HUS”

A

E. coli 0104: H4

77
Q

Identify the E. coli pathotype (ETEC, EPEC, EHEC, EIEC, EAEC, DAEC)

“The strains are closely related by phenotyping and pathogenic properties to Shigella”
“The bacteria are able to invade and destroy the colonic epithelium, producing a disease characterized initially by watery diarrhea”
“A minority of patients progress to the dysenteric form of disease, consisting of fever, abdominal cramps, and blood and leukocytes in stool specimens”
“Can progress into ulceration”

A

Enteroinvasive E. coli (EIEC)

77
Q

What are examples of treatments for Enteric E. coli (Pathotypes) as a substitute for prophylaxis?

A

Ciprofloxacin
Trimethoprimsulfamethoxazole

78
Q

It is a disorder characterized by acute renal failure, thrombocytopenia, and microangiopathic hemolytic anemia and is associated with EHEC

A

Hemolytic Uremic Syndrome (HUS)

78
Q

Identify the E. coli pathotype (ETEC, EPEC, EHEC, EIEC, EAEC, DAEC)

“All members of this group are defined by the presence of Shiga toxin”
“Some but not all are LEE positive and form A/E cytopathology, resembling EPEC strains”
“Most common in warm months, and highest incidence is in children younger than 5 years old”

A

Enterohemorrhagic E. coli (EHEC)

78
Q

Identify the E. coli pathotype (ETEC, EPEC, EHEC, EIEC, EAEC, DAEC)

“Recognized as the 6th class of diarrheagenic E. coli and appear as a heterogenous group”
“Ability to adhere to HEp-2 cells in a diffuse pattern in which the bacteria uniformly cover the entire cell surface”
“Capable of causing diarrheal disease, primarily in children aged 2-6 years”

A

Diffusely-adherent E. coli (DAEC)

79
Q

Pathogenic strains of EIEC are primarily associated with a few restricted O serotypes which are?

A

O124
O143
O164

80
Q

Who is the bacteriologist that was named after the Klebsiella spp?

A

Theodor Albrecht Edwin Klebs

81
Q

Klebsiella pneumoniae was initially known as?

A

Friedlander’s bacterium

82
Q

“Brick-red” or “Currant Jelly sputum”, were known to be caused by Friedlander’s bacillus or?

A

Klebsiella pneumoniae

82
Q

What strains of K. pneumoniae are considered global priority pathogens?

A

ESBLs (Extended-spectrum beta-lactamases)
Carbapenemases

83
Q

True or False

K. pneumoniae are:

Catalase: Positive
Oxidase: Negative
Lactose fermenter
Mucoid colonies
Non-motile

A

True

83
Q

It is the most frequently isolated Enterobacter species from man and animals feces

A

Enterobacter cloacae

84
Q

Colony characteristic of Klebsiella pneumoniae:

Blood Agar:
MacConkey Agar:

A

Blood Agar: Mucoid, non-hemolytic
MacConkey: Mucoid, lactose-fermenting (pink colored)

84
Q

What are notable opportunistic pathogens of Enterobacter? (SAGAC)

A

E. sakazakii
E. aerogenes
E. gergoviae
E. agglomerans
E. cloacae

84
Q

IMVC for Klebsiella pneumoniae

IMVC Positive:
IMVC Negative:

A

IMVC Positive: Indole and Methyl Red

IMVC Negative: Voges-Proskauer and Citrate

85
Q

A species of Enterobacter that can behave as an opportunistic pathogen in immunologically compromised patients.

A

E. agglomerans

85
Q

True or False

The bacteria below are considered to be OPPORTUNISTIC pathogens and NOT ENTERIC

E. cloacae
E. sakazakii
E. aerogenes
E. agglomerans
E. gergoviae

A

True

86
Q

A species of Enterobacter that have been implicated in a long term-nosocomial outbreak of urinary tract infections

A

E. gergoviae

86
Q

A species of Enterobacter that is often commensal without clinical significance and is occasionally a pathogen causing neonatal meningitis and bacteremia

A

E. sakazakii

86
Q

Recommended Media for E. coli: Culture and Maintenance

A

Blood Agar 5%
TSA Agar
Nutrient Agar

86
Q

Serratia are positive for these Biochemical Tests (DGLO)

A

DNAse
Gelatinase
Lipase
ONPG

86
Q

True or False

For differential of E. aerogenes and E. cloacae, they are BOTH POSITIVE for Ornithine decarboxylase

A

True

86
Q

True or False

For differential of E. aerogenes and E. cloacae, they are BOTH NEGATIVE for Alginate Utilization Test

A

True

86
Q

Differential Test: E. aerogenes

Lysine decarboxylase:
Arginine dihydrolase:
Urease:

A

Lysine: Positive (+)
Arginine: Negative (-)
Urease: Negative (-)

87
Q

Media used for Selective Isolation of Hafnia alvei (5)

A

EMB (Eosin Methylene Blue)
MacConkey Agar
Hektoen Enteric Agar
SS (Salmonella-Shigella Agar)
XLD Agar (Xylose Lysine Deoxycholate)

87
Q

Differential Test: E. cloacae

Lysine decarboxylase:
Arginine dihydrolase:
Urease:

A

Lysine: Negative (-)
Arginine: Positive (+)
Urease: Weakly positive

87
Q

It is the most common clinical isolate and most important human pathogen in Serratia species

A

S. marcescens

87
Q

Colonies of this bacteria and are non-lactose fermenters and may resemble SALMONELLAE

Most strains are translucent or colorless

Media containing sucrose: Red or Pink colonies

A

Hafnia alvei

87
Q

Media used for Maintenance of Hafnia alvei (1)

A

CTA (Cystine Tryptic Agar) at room temperature for up to 1 year

88
Q

3 species of Serratia best known for clinical infections

A

S. marcescens
S. liquefaciens
S. odorifera

88
Q

IMVC reaction of Serratia spp

A

IMVC: - , - , + , +

89
Q

Media used for culture of Hafnia alvei (2)

A

Tryptic Soy Agar
Blood Agar 5%

90
Q

An opportunistic pathogen which is one of the common cause of UTI and are associated with “Infection-Induced Renal Stones”

A

Proteus

91
Q

Certain strains of Proteus vulgaris produce O antigens that are shared by some rickettsiae which are?

A

OX-19
OX-2
OX-K

92
Q

Proteus strains are used in this agglutination test for serum antibodies produced against rickettsiae of the typhus and spotted fever groups

A

Weil-Felix Test

93
Q

Why is the urease enzyme produced by Proteus species play a major role in the production of infection induced urinary stones?

A

The ammonia produced after breakdown of urea forms struvite stone formation (magnesium ammonium phosphate)

Recurrent UTI with urease-producing organisms forms “STAGHORN CALCULI” in the kidney

94
Q

What is the only difference of Proteus mirabilis and Proteus vulgaris in IMVC?

A

P. mirabilis = Indole negative (-)
P. vulgaris = Indole positive (+)

95
Q

Between Blood Agar and MacConkey Agar, which does Proteus swarm?

A

Blood agar = swarms
MacConkey = does not swarm

96
Q

Several methods to inhibit swarming of proteus

A

Increased agar concentration from 1-2% to 6%

Choral hydrate (1:500)
Sodium azide (1:500)
Boric acid (1:1000)

Using of Cysteine Lactose Electrolyte Deficient (CLED) as a medium instead of Blood Agar and MacConkey Agar for URINE samples

97
Q

When two different strains of P. mirabilis swarm on the same agar plate, a visible demarcation line with lower cell density forms at the intersection, and this line is known as? (Hint: named after Louis Dienes)

A

Dienes Line or Dienes phenomenon

98
Q

Some Morganella strains appear hemolytic when cultured on BA, while others produce what color pigmentation?

A

Reddish-brown pigmentation

99
Q

Culture Media for Morganella spp. (2)

A

TSA and BA 5%

100
Q

Maintenance Media for Morganella spp. (2)

A

Tryptic Soy Agar - short term
Lyophilization - long term

100
Q

Selective Isolation Media for Morganella spp (4)

A

MacConkey Agar
EMB Agar
Selenite Broth
Tetrathionate Broth

101
Q

Providencia IMVC result:

A

IMVC: + , + , - , +

101
Q

Identify bacteria based on Macroscopic Appearance:

Large
Dull gray colonies
Non-swarming
Colorless on enteric agar

A

Providencia spp.

101
Q

Selective Isolation Media for Citrobacter (9)

A

MacConkey
EMB
XLD
Selenite Broth
Tetrathionate Broth
SS Agar
Deoxycholate Agar
Brilliant Green Agar (BGA)
Bismuth Sulfite Agar (BSA)

101
Q

Example of Enteric Agars (3)

A

EMB Agar
HE Agar
SS Agar

101
Q

Strains of Providencia _________ and Providencia _________ may produce wound and burn infections

A

P. stuartii and P. rettgeri

101
Q

2 species of the genus Salmonella

A

S. enterica
S. bongori

101
Q

Common habitat is Extraintestinal tracts (stool samples) of humans and animals (particulary “Poultry”

A

Providencia spp.

101
Q

Maintenance agar for Citrobacter

A

Nutrient Agar
TSA
Brucella with 20% Glycerol
Skim Milk (storage at -70C)
Lyophilization (long term preservation)

102
Q

Culture Media for Providencia spp. (2)

A

Tryptic Soy Agar
Blood Agar 5%

102
Q

Selective Isolation Media for Providencia spp.

A

Simmons Citrate Agar (SCA)
MacConkey Agar
Tergitol Agar
CHROMtm UTI

102
Q

Culture Media for Citrobacter (3)

A

Nutrient Agar
TSA
BA

102
Q

Recommended pH for Media of Citrobacter

A

6.8 - 7.2

103
Q

Maintenance Media for Providencia spp.

A

TSA or BA5%
Brucella with 20% Glycerol or Skim Milk (Long term storage at -70C)
Lyophilization for preservation

103
Q

2 Classification of Salmonella based on their serotype

A

Typhoidal and Non-Typhoidal

104
Q

Most cases of foodborne disease in humans are caused by bacteria belonging to what Salmonella subspecies?

A

Salmonella enterica

105
Q

Only Salmonella that lives in HUMANS: Human acquired

A

Salmonella typhi

106
Q

It is acquired by consuming contaminated meat or animal products (EGGS)

A

Salmonella

107
Q

True or False

Salmonella typhi or S. typhi have no complex nutritional requirements and readily grow in an ordinary media like Nutrient Agar medium (NA)

A

True

108
Q

Examples of Selective Medium for Salmonella and Shigella

A

DCA medium
SS Agar medium
Wilson & Blair bismuth sulfite medium
XLD medium
Tetrathionate broth
Selenite F broth
Trypticase and Nutrient broth (Liquid Medium)

108
Q

What type of hemolysis does Salmonella typhi present in Blood Agar?

A

Gamma hemolysis (no-hemolysis)
Colony color: Grayish-white

108
Q

These species of Shigella are more resistant because they can tolerate low temperature if adequate moisture is present

A

Shigella sonnei

108
Q

For feces specimen, these 2 are the commonly used for the isolation of Salmonella typhi

A

Selentie F broth
Tetrathionate broth

108
Q

Causative agent of bacillary dysentery (stool containing blood and pus)

A

Shigella

108
Q

In Xylose Lysine Dextrose Agar (XLD) medium, what are the results expected?

A

Red: due to the fermentation of xylose which lowers the pH of the medium

Pink or Red: presence of Phenol Red

Black center: production of Hydrogen sulfide (H2S)

108
Q

Deoxycholate Citrate Agar medium result for Salmonella typhi

A

Colorless because it is NLF

108
Q

Shigella are differentiated by what antigen?

A

O antigen

108
Q

MacConkey Agar for Shigella:

A

Pale and Yellowish (Non-lactose fermenting)

Exception: S. sonnei being late lactose fermenting (turns pink)

108
Q

Subgroup of Shigella:

named after “Sonne” in Germany
Ferment lactose and sucrose late
Indole negative
Causes “mildest form” of bacillary dysentery

A

Subgroup D (Shigella sonnei)

108
Q

Subgroup of Shigella:

consists of dysentery bacilli
resembles S. flexneri biochemically, but not antigenically
named after “Boyd” who discovered it from India
Isolates “least frequently”

A

Subgroup C (Shigella boydii)

108
Q

It is a clinical condition of multiple etiology characterized by frequent passage of blood-stained mucopurulent stool

A

Dysentery

108
Q

Subgroup of Shigella:

Named after “Flexner” from Philippines
Mannitol fermenting shigella

A

Subgroup B (Shigella flexneri)

109
Q

Subgroup of Shigella:

mannitol non-fermenting
Forms a “toxin”
3 types of toxic activity (Neurotoxicity, enterotoxicity, cytotoxicity)

A

Subgroup A (Shigella dysenteriae)

109
Q

Shigellosis has high death rate especially in young children. Most deaths are caused by?

A

S. dysenteriae type 1

109
Q

These virulent factors of Y. pestis inhibit phagocytosis and intracellular killing of bacterium inside macrophages

A

V antigen (protein)
W antigen (acidic lipoprotein)

109
Q

The “Best” selective media for Shigella and have “RED” colonies

A

XLD (Xylose Lysine Deoxycholate) Agar

109
Q

4 structures or subgroup of Shigella

A

Subgroup A (Dysenteriae)
Subgroup B (Flexneri)
Subgroup C (Boydii)
Subgroup D (Sonnei)

109
Q

These consists of many proteins which facilitates secretion of virulent factor of Y. pestis in host cells

Resist phagocytic killing and inhibits production of cytokines, which results in reduced inflammatory immune response to infection

A

Type III secretion system (TTSS)

109
Q

It is a broth which enrich S. sonnei and S. flexneri but inhibitory to other Shigella

A

Selenite F-broth

109
Q

3 pathogenic Yersinia spp.

A

Y. pestis
Y. pseudotuberculosis
Y. enterocolitica

109
Q

It is a heat labile protein produced only in the virulent strains when cultures are incubated at 37C in Y. pestis

A

F1 antigens

109
Q

This Yersinia spp. is responsible for “RED-MOUTH” , “PINK MOUTH” , or “PINK OR RED THROAT” of salmon and trout

A

Yersinia ruckeri

109
Q

These are proteins in nature possessing some properties of BOTH exotoxins and endotoxins

A

Murine toxins (active in rats and mice)

109
Q

Yersinia spp. which is the most important cause of food borne illness

A

Yersinia enterocolitica

109
Q

What Yersinia species caused the Plague (Black Death)?

A

Yersinia Pestis

109
Q

Yersiniosis is caused by what serogroups of Yersinia enterocolitica?

A

O:3
O:5
O:8
O:9
O:27

109
Q

True or False

habitat of Y. pestis are found in dogs, squirrels, rabbits, mice, and etc

A

True

109
Q

It refers to the endotoxin and murine toxins found in culture filtrates or cell lysates of Yersinia pesits

A

Plague toxin

109
Q

These are di-polysaccharide found in the cell wall and is responsible for many of the systemic manifestation of the disease caused by Y. pestis

A

Endotoxin

109
Q

Christensen’s Urea Agar for Yersinia

Y. enterocolitica =
E. coli =

A

Y. enterocolitica = Pink color (urease positive)

E. coli = no color (urease negative)

109
Q

Bile Esculin Agar (Yersinia spp.)

Y. enterocolitica =
Enterococcus faecalis =

A

Y. enterocolitica = esculin negative (absence of black color) (except biotype 1A)

Ent. faecalis = esculin positive (black color)

Bacteriology Lecture (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions