Brainscape's Knowledge GenomeTM

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


See full index

MICROM 442 > Exam 3 Lecture 22 > Flashcards

Exam 3 Lecture 22 Flashcards

1
Q

Describe the gram stain of Campylobacter and Helicobacter

A

gram-negative helical rods

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

Campylobacter and Helicobacter are part of which broad group?

A

Epsilonproteobacteria

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

True or false: though they were discovered in the last 50 years, Campylobacter and Helicobacter are common bacterial pathogens

A

True

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

Campylobacter and Helicobacter are _____ and ____

A

microaerophilic; fastidious

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

Campylobacter and Helicobacter infect the __ ___ of humans and other animals

A

GI tract

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

True or false: Campylobacter and Helicobacter do not have flagellar motility

A

False

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

C. jejuni has ____ flagella, which contributes to what kind of motility?

A

bipolar; darting motility

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

Lophotrichous flagella

A

Multiple flagella found at one end of the bacterium

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

H. pylori has ____ flagella, which allows for:

A

lophotrichous; penetration of mucus (which likely attributes to its ability to get into the tissue and cause infection)

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

How do Campylobacter and Helicobacter have molecular mimicry?

A

Their LPS/LOS structures mimic host glycosylation, which can induce autoantibodies (those that mistakenly target the host)

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

How many species of Campylobacter do we know of? How many subspecies?

A

32 species; 9 subspecies

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

True or false: Campylobacter is the major cause of foodborne bacterial infections in developed nations

A

True (more than Salmonella, E. coli, Shigella combined)

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

Does Campylobacter cause disease via low or high inoculum?

A

Low (400-500 sufficient to cause infection)

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

Most Campylobacter infections are caused by:

A

C. jejuni

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

C. coli attributes to -% of Campylobacter infections

A

1-25%

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

True or false: Campylobacter can commonly colonize domestic animals where it doesn’t cause much disease.

A

True

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

C. jejuni causes ____, which consists of what symptoms?

A

Enteritis; symptoms = diarrhea; sometimes bloody, fever, abdominal pain, inflammation

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

C. jejuni symptoms usually appear in __-__ hours. The range is - days.

A

24-48 hours; 1-7 days

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

True or false: C. jejuni enteritis usually is self-limiting and resolves within a week

A

True

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

Sometimes, C. jejuni infection can become _____, which can lead to other diseases, such as:

A

extraintestinal; biliary tract, bacteremia, meningitis, others

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

How is C. jejuni infection treated?

A

fluids and electrolytes, antibiotics for severe infections

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

True or false: antibiotic resistance is a problem when treating C. jejuni

A

True - presumably due to resistance having developed in livestock

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

Which antibiotics are used for treating C. jejuni?

A

Azithromycin, Ciprofloxacin

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

True or false: For diagnosing C. jejuni, culture via selective media is the gold standard

A

True

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

Besides culture, what are some other ways to diagnose C. jejuni?

A
  1. looking for darting motility in fresh stool samples

2. serum serology and PCR

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

Most cases of C. jejuni are due to ____ ____

A

sporadic zoonosis

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

You can contract C. jejuni infection through: (2; hint - one is rare)

A
  1. contaminated/undercooked poultry

2. (rare) pets, contact with farm animals, person to person

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

True or false: raw milk or untreated water can cause outbreaks in C. jejuni

A

True

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

C. jejuni cases peak during ___ ___

A

warmer months

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

What are the four steps of C. jejuni pathogenesis?

A
  1. adheres to intestinal epithelial cells
  2. induced toxin-mediated cell damage
  3. uses cytolethal distending toxin to induce cell cycle arrest
  4. performs endocytosis and transcytosis (which is thought to be important for immune evasion)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

True or false: C. jejuni flagella are required for infection

A

True (darting motility)

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

Regarding C. jejuni flagella, FlaA and FlaB expression can be turned on or off due to ___ ____, which is controlled by ___-___ ____

A

phase variation; slip-strand mispairing

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

Which flagellin monomers make up the C. jejuni flagella?

A

FlaA and FlaB

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

True or false: generally, bacterial flagella are normally glycosylated

A

False

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

C. jejuni flagellin glycosylation is important for _______ and _____ _____

A

autoagglutination; microcolony formation

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

Besides making up the flagellar structure, what else is the basal body in C. jejuni responsible for?

A

Exporting other proteins, such as FlaC, Cia proteins, and FspA

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

Generally, flagella are made via what type of secretion system?

A

(Modified) T3SS

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

Name the C. jejuni virulence factors (7)

A
  1. motility
  2. chemotaxis
  3. adhesion and invasion
  4. capsule
  5. iron uptake
  6. biofilm formation and antibiotic resistance
  7. LPS/LOS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Describe the chemotaxis of C. jejuni

A

attracted to mucus, glycoproteins of mucus, nutrients

repelled by bile

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

C. jejuni adheres to host ____ via what proteins?

A

CadF and FlpA

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

Which protein of C. jejuni binds to host heat shock protein?

A

JlpA

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

True or false: C. jejuni flagella are thought to be important for adhesion to host cells.

A

True

43
Q

True or false: in addition to FlaA/FlaB expression, C. jejuni turns capsule biosynthesis on/off via slip-strand mispairing

A

True

44
Q

C. jejuni capsule is important for:

A

survival, adherence, immune evasion

45
Q

How many serotypes exist in C. jejuni?

A

over 100

46
Q

What serotypes are associated with GBS?

A

Serotypes O19 and O41

47
Q

What type of toxin is CDT?

A

AB2

48
Q

CdtB gene codes for? And what functions does this protein product have?

A

A subunit of the CDT toxin; has DNase and phospholipase activity

49
Q

What do CdtA and CdtC genes code for?

A

binding subunits of the AB2 CDT toxin

50
Q

CdtA and CdtC bind to ____-rich regions on the host cell membrane and drives internalization of the toxin via _____-____ __

A

cholesterol; clathrin-coated pits

51
Q

True or false: the CDT toxin is unique solely in C. jejuni

A

False - found in many Gram negative organisms, such as E. coli, H. ducreyi, Helicobacter spp, S. Typhi, Shigella

52
Q

How does C. jejuni CDT cause cell cycle arrest/apoptosis?

A

B subunit migrates into the nucleus, induces double strand breaks; also activates ATM, p53

53
Q

What does GBS syndrome cause?

A

ascending paralysis

54
Q

Approximately _/___ patients develop GBS after C. jejuni infection

A

1/1000

55
Q

True or false: GBS correlates with presence of anti-GM1, anti-GD1a, IgG (antibodies against host proteins)

A

True - this attributes to paralysis

56
Q

In GBS, antibodies that are produced attack the ___ and assemble complement, essentially destroying the ___

A

nerves

57
Q

In addition to causing GBS, C. jejuni can also cause ____ ____

A

reactive arthritis

58
Q

C. fetus major reservoir

A

animals such as cattle, sheep, reptiles

59
Q

C. fetus grows optimally at __ºC

A

37ºC

60
Q

C. fetus can cause ____ and ___ ___

A

diarrhea; fetus loss

61
Q

True or false: C. fetus was the first Campylobacter characterized

A

True

62
Q

____ grows more slowly than Campylobacter

A

Helicobacter

63
Q

True or false: there is a correlation between H. pylori and peptic cancer

A

True

64
Q

H. pylori infection occurs ___ in life and can ____ for life

A

early; persist

65
Q

What is the H. pylori reservoir?

A

stomach

66
Q

H. pylori is ____ transmitted within families. As such, there is a strong ____ ____ to the genetic variation of Helicobacter spp.

A

vertically; ethnogeographic signature

67
Q

Most cases of H. pylori are ____ ____

A

asymptomatic gastritis

68
Q

H. pylori can cause what type of ulcers?

A

gastric and duodenal ulcers

69
Q

H. pylori can also cause ___ ___ ___ ___, which resolves upon eradication of infection.

A

Mucosa Associated Lymphoid Tissue

70
Q

Asymptomatic gastritis is characterized by? (3)

A
  1. neutrophil infiltration
  2. proinflammatory cytokines (increases acid)
  3. can progress to atrophic gastritis (loss of parietal cells, less acid)
71
Q

Parietal cells

A

epithelial cells that line the stomach and secrete HCl

72
Q

What does H. pylori gastritis look like?

A

bumpy lining, hyperplasia, loss of parietal cells, immune cells infiltrate, inflammation

73
Q

How does H. pylori survive the acidic environment of the stomach?

A

secretes urease

74
Q

True or false: patients with gastric cancer know early on that they have it

A

False - often is silent until tumor grows so large that it becomes hard to eat

75
Q

True or false: MALT lymphoma is rare

A

True

76
Q

H. pylori gastric cancer ___ doesn’t match ___. Ex: China

A

incidence; prevalence

77
Q

H. pylori diagnosis (4)

A
  1. urea breath test (carbon isotope)
  2. stool antigen test
  3. serological test (anti-H. pylori IgG)
  4. endoscopy and biopsy (for culture and histology purposes)
78
Q

Do we treat H. pylori if there are no symptoms?

A

No

79
Q

If there are symptoms or cancer risk, treat H. pylori with:

A

Combination therapy

  • 2 antibiotics
  • drug to reduce acid
  • bismuth to promote mucosal healing
80
Q

True or false: H. pylori treatments rarely fail

A

False- it can happen so we are wary of it due to resistance, pH effect on drugs, non-compliance due to long course of treatment

81
Q

Majority of H. pylori live in:

A

mucus layer overlying the gastric epithelium

82
Q

Urease has two main functions, which are:

A
  1. buffers stomach acid via cleaving urease to make NH3

2. changes rheological properties of mucin to make it easier to swim through

83
Q

H. pylori uses ___ ___ and ____ __ __ to get to epithelium

A

flagellar motility; helical cell shape

84
Q

H. pylori toxins (3)

A

VacA, Nap, CagA

85
Q

VacA

A

vacuolating cytotoxin

86
Q

Nap

A

recruit immune cells

87
Q

CagA

A

subvert host cell signaling

88
Q

H. pylori uses adhesins __ and __ to bind to? (respectively)

A

BabA and SabA; lewis antigens; sialyl-lewis antigens

89
Q

True or false: there is molecular mimicry with H. pylori due to Lewis antigens on LPS

A

true

90
Q

VacA has different ___ ___ ___ which can lead to higher/lower levels of its expression and binding ability

A

signal sequence polymorphisms

91
Q

VacA induces cells to fill up with big ____, which is ____. It also increases the ____ of the epithelium

A

vacuoles; cytostatic; permeability

92
Q

VacA can induce apoptosis via interaction with?

A

mitochondria

93
Q

VacA can inhibit _-___

A

T- cells

94
Q

Cag is coded within _____ ___

A

pathogenicity island

95
Q

Cag is associated with ___ and ___

A

ulcer and cancer

96
Q

Cag is displaced into a host cell via what secretion system?

A

T4SS

97
Q

Cag induces _____ ___

A

proinflammatory cytokines

98
Q

translocation of CagA into host does what two things?

A
  1. activate growth receptor signaling pathways

2. induce cell shape changes and motility

99
Q

True or false: Cag pathogenicity island is found in all strains of H. pylori

A

False - only in some strains, but found in those associated with causing ulcers/cancer

100
Q

CagA has ___ motifs. East Asians in particular have the _ motif which binds ___ much more tightly.

A

EPIYA; D; SHP-2

101
Q

SHP-2 binds to what specifically?

A

Phosphorylated Y within EPIYA

102
Q

True or false: Kids who have H. pylori are much more likely to have asthma and other allergic conditions

A

False: less likely

103
Q

Regarding H. pylori, protection against allergies/chronic inflammatory disorders is mediated through ____ _ ___

A

regulatory T cells

MICROM 442 (26 decks)

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