Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Microbiology > Clostridium-Bacillus (EXAM III) > Flashcards

Clostridium-Bacillus (EXAM III) Flashcards

1
Q

Describe the gram stain & shape of Clostridium bacteria:

A

Gram positive; rods

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

A major virulence factor of Clostridium is that:

A

Endospore forming

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

Describe the oxygen requirement of Clostridium & spores:

A

Obligate anaerobes; spores are O2 resistant

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

Where can Clostridium be encountered:

A

Environment (soil) & intestinal mucous

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

How can we detect spores of Clostridium:

A

Endospores stain hot malachite green

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

Endospore staining is also used for:

A

Aerobic endospore formers like Gram + bacillus

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

Describe the virulence factors of Clostridium:

A

Spore formation

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

The spores of clostridium contribute to virulence because:

A
  1. Resistant to destruction
  2. Resistant to sterilization
  3. Resistant to antibiotics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How might we remove clostridium spores from a medical device?

A

Autoclave (Heat under pressure)

Boiling is NOT effective

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

When the disease-causing components is solely due to the toxin, this is referred to as:

A

Intoxication

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

The type of Clostridium that gives rise to severe form of food poisoning leading to paralysis if untreated:

A

Clostridium Bolulinum

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

In addition to food ingestion, Clostridium Botulinum may cause Botulism by:

A

Soil or fecal contamination

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

_______ is possible form soil or fecal contamination

A

Wound botulism

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

Explain how infant botulism occurs:

A

Because of lack of full development of normal intestinal flora, if Clostridium Botulinum is introduced to infant between weeks 30 & 20 it has the capability of rapid overgrowth

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

Describe the effects of infant botulism:

A

Muscle weakness; rarely paralysis

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

How does infant botulism resolve?

A

Normally resolves as intestinal flora develops

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

Describe the virulence factors of Clostridium Botulinum:

A

Botulinum neurotoxin (A-B exotoxin) blocks acetylcholine release

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

What does botulinum neurotoxin (A-B exotoxin) block & what does this cause?

A

Blocks Acetylcholine release; causes flaccid paralysis - can lead to death

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

Because Clostridium botulinum does not ______ it acts through _____

A

Invade tissues; toxins

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

The spores of clostridium botulinum are _____, while the botulinum toxin is _____

A

Heat-stable; heat-labile

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

How long does anti-toxin neutralization to the botulism toxin take to be effective?

A

Weeks to months

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

The form of Clostridium that is typically caused by dirty, puncture wounds (knife, bullet, tattoo) that are typically opportunities for the anaerobic growth of this pathogen:

A

Clostridium tetani

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

Describe the oxygen requirements of Clostridium Tetani:

A

Anaerobic

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

Bacterial growth of Clostridium Tetani remains _____ but the tetanus toxin _____

A

Localized; spreads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What toxin is responsible for the virulence of Clostridium Tetani?
Tetanospasmin
26
Describe Tetanospasmin:
Tetanus A-B exotoxin/neurotoxin; plasmid encoded
27
Describe the mechanism of action of tetanospasmin:
Blocks GABA & Glycine; leads to loss of inhibitory input to motor neuron excitation leading to spastic paralysis
28
In Clostridium tetani, the spastic paralysis is due to:
Uncontrolled muscle contraction caused by Tetanospasmin
29
The effects of Tetanospasmin may be:
Localized & one-sided (on opposite side of infection)
30
Describe the effects of anti-toxin against tetanospasmin:
Usually too late for anti-toxin treatment
31
Clostridium Tetani does not _____ so it acts through _____
Invade tissues; toxins
32
A dramatically deadly disease characterized by the in ability of muscle relaxation:
Tetanus
33
Tetanus toxin prevents:
Muscle relaxation
34
Infection with tetanus systemically can cause:
1. Cardiac arrythmias 2. Blood pressure swings 3. Dehydration
35
A characteristic symptom of tetanus:
Lock jaw
36
Tetanus effects can be _____ or _____
General or localized
37
Describe tetanus vaccination of pregnant women:
Passive immunization (IgG) of pregnant women can prevent neonatal tetanus death by umbilical infection (250,000 per year worldwide)
38
The ONLY clostridium species with tissue invasion:
Clostridium Perfringens
39
Organisms that often cause problems when you have an infection from a dirty wound, as these bacteria can be deep down into a relatively anaerobic environment that allows them to begin growing & invading the tissue:
Clostridium Perfringens
40
The tissue invasion seen by Clostridium Perfringens is furthered by:
Virulence factors that allow these bacteria to lyse cells & destroy tissue integrity
41
List the virulence factors associated with Clostridium Perfringens:
1. Alpha-toxin 2. Theta-toxin 3. Collagenase & Hyaluronidase
42
Describe the mechanism of action of the alpha-toxin in Clostridium perfringens:
Hemolytic property resulting in membrane destruction
43
Describe the mechanism of action of the alpha-toxin in Clostridium perfringens:
Cytolytic toxin that results in cell killing
44
Describe the mechanism of action of the collagenase & hyaluronidase in Clostridium perfringens:
Faciliates tissue invasion from the edges of necrotizing tissues
45
Which virulence factor of Clostridium Perfringens is responsible for its ability to invade tissue:
Collagenase & Hyaluronidase
46
Describe the mechanism of reaction seen in Clostridium Perfringens:
Anaerobic fermentation of amino acids leads to increased gas production (H2, CO2) resulting in gas gangrene
47
The anaerobic fermentation of amino acids seen in Clostridium Perfringens infections results in:
Gas gangrene
48
What childbirth complication has been associated with Clostridium Perfringens:
Puerperal "Childbed" fever (Uterine gangrene)
49
Describe the treatment against Clostridium Perfringens:
No vaccination possible; antibody against the alpha-toxin but fails to stop gangrene-- typically amputation is best option if gangrene occurs
50
List the three types of Clostridium that do NOT invade tissues:
1. C-Diff 2. Botulism 3. Tetanus
51
A super infection resulting from broad-spectrum antibiotics that kill much of the other normal intestinal bacterial flora, giving rise to a resistant species of this harmful bacteria:
Clostridium Difficile
52
Antibiotic-associated pseudomembrane colitis is caused by:
Clostridium Difficile
53
C-Diff may be observed after:
Antimicrobial chemotherapy
54
One of the leading causes of hospital-acquired diarrhea:
Clostridium Difficile
55
Results from broad-spectrum antibiotics that kill much elf the other normal intestinal bacterial flora, giving species like toxin-producing Clostridium difficile a chance to take over:
Antibiotic-associated pseudomembranous colitis
56
List the virulence factors of Clostridium difficile:
1. Toxin A 2. Toxin B
57
Describe the effects of Toxin A in C-diff:
Inhibits intestinal tight-junctions leading to fluid leakage
58
Describe the effects of Toxin B in C-diff:
A cytotoxin that functions in actin depolymerization and rounding of epithelial cells leading to fluid leak
59
Both toxin A & toxin B in C-diff cause fluid leak ultimately causing:
Diarrhea
60
CDC 2013 report states that _____ is a major threat to antibiotic resistance in the US
C-diff
61
What clostridium bacteria is this describing? Treatment: Botulinum antitoxin
C. Botulinum
62
What clostridium bacteria is this describing? Treatment: Toxoid vaccination
C. Tetani
63
What clostridium bacteria is this describing? Treatment: Anti-tetanus serum (passive immunity)
C. Tetani
64
What clostridium bacteria is this describing? Treatment: Surgery intervention, amputation
C. Perfringens
65
What clostridium bacteria is this describing? Epidemiology: Environment (soil, water, sewage) & GI tract in animals & humans
C. Botulinum C. Tetani C. Perfringens
66
What clostridium bacteria is this describing? Epidemiology: Colonized intestines, genital tract, hospital environment, prior antibiotics
C. Difficile
67
Describe the shape & gram stain of bacillus:
Gram positive; rods
68
B. anthracis gives rise to ______ & is considered a _______infection
Woolsorter's disease; zoonotic infection
69
Describe the oxygen requirements of B. Anthracis:
Facultative anaerobe
70
List the virulence factors of B. Anthracis:
Anthrax toxins (edema-factor & lethal-factor) & a poly-glutamic acid capsule
71
Describes the difference between the Anthrax toxins Edema-factor & Lethal-factor:
The differences lie within the A-component (the B-components are the same)
72
Describe the A-component of Edema-factor (EF) found in bacillus anthracis:
EF is an adenylate cyclase that DIRECTLY leads to increased cAMP levels and results in edema
73
Describe the A-component of Lethal-factor (LF) found in bacillus anthracis:
LF is a metallo-protease that targets MAP kinase (an important signaling molecule) ultimately leading to cell death
74
Describe the capsule of B. Anthracis:
Its a poly-glutamic acid capsule that functions to inhibit phagocytosis
75
Form of anthrax in which spores are uptake by the lungs and then enter lung phagocytes; latency of 2 months or more may occur:
Inhalation anthrax
76
Following the entry into lung phagocytes in inhalation anthrax where do the spores travel to?
Lymph nodes
77
In anthrax infections if the spores travel to the lymph nodes (from the lungs) the spores germinate causing phagocyte death and ultimately lead to:
Pneumonia & meningitis type symptoms
78
In an anthrax infection if spores germinate and produce toxins that enter the bloodstream this can trigger:
Macrophage TNF-alpha leading to toxic shock death in 1-2 days
79
In what situation may an anthrax infection lead to toxic shock & death:
If toxins enter the bloodstream
80
In what situation may an anthrax infection lead to symptoms of pneumonia & meningitis:
If toxins & spores spread to lymph nodes
81
Form of anthrax infection that leads to ulcers in the mouth & esophagus, edema & sepsis:
Gastrointestinal anthrax
82
In what case would gastrointestinal anthrax become nearly 100% lethal?
In lower intestine
83
Describe skin anthrax infections:
Redness & edema with rupturing vesicles
84
What lethality rate of skin anthrax infections:
20%
85
List the epidemiology of Bacillus anthracis:
1. Animal workers 3. Microbiological accidents 3. Bioterrorism 4. Contaminated meat

Microbiology (22 decks)

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