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Flashcards in Anaerobic Bacteria Deck (18)
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1
Q

What do aerobic bacteria have that anaerobic bacteria don’t to survive?

A

Aerobic Bacteria have: Superoxide Dismutase, Catalase, and use cytochromes.
Without these oxygen is toxic to organisms.

2
Q

Common features of gram negative anaerobic bacteria?

A

Typically infection sites are colon, skin, and mouth. Foul smelling gas production due to fermentation. Usually from normal flora infecting other tissues.

3
Q

Where does Bacteriodes Fragilis usually infect and what are it’s virulence factors?

A

Most common for intraabdominal infections.

Virulence factors: Polysaccharide capsule, encodes oxidative stress genes to tolerate oxygen.

4
Q

What common other microbe is B. Fragilis with in intraabdominal infections?

A

Peptostreptococcus - Gram Positive, anaerobe

5
Q

What classifies Clostridia organisms?

A

Gram Positive, spore forming bacilli, and anaerobic or tolerate.

6
Q

When is most common to get an infection of C. Difficile?

A

After undergoing treatment of antibiotics, which reduce the natural flora allowing C. Difficle to expand producing toxins.

7
Q

What are the toxins of C. Difficle and what do they cause?

A

Toxin A and Toxin B, Glucosylate Rho disrupting actin depolymerization, thus disrupting gut epithelium causing diarrhea.

8
Q

What is the treatment of C. Difficle?

A

Metronidazole, Vancomycin, and Fluoroquinones

9
Q

Where does Clostridia Perfringens typically infect and what type of clostridia is it?

A

Histotoxic Clostrida - typically after deep wounds that predispose for infection.

10
Q

Why are deep wounds susceptible for C. Perfringens?

A

Due to the tissue death releasing lactate and lowering pH and host proteases breaking down dead cells that release nutrients for C. Perfringens, which release toxins causing gangrene. Treatment = Abx and Amputation

11
Q

What are the two types of organisms that produce neurotoxins?

A

C. Botulinum and C. Tetani

12
Q

What is the common mechanism of BoNT and TeNT?

A

They are neurotoxins that cleave SNARE proteins inhibiting release of vesicles.

13
Q

How does BoNT and TeNT cause unique symptoms?

A

BoNT inhibits ACh release in peripheral neuron muscular junctions causing flaccid paralysis.
TeNT enters the CNS inhibiting interneurons causing spastic paralysis.

14
Q

How do you become infected with C. Tetani?

A

Usually a wound that gets infected by a mix of organisms allowing C. Tetani to grow enough to produce toxins that spread systemically. C. Tetani is non-invasive residing at the site of infection.

15
Q

What are the components of vaccines regularly given when young?

A

DTaP - diptheria, tetanus, and pertussis
Uppercase = full dose
Lower case = partial dose
“a” means acellular dose

16
Q

What are the ways to be affected by C. Botulinum?

A

Food Bourne - microbe produces toxins in caned food and person ingests the toxin itself.
Colonization of C. Botulinum in GI or in a wound, which then produces the toxin into blood stream.
–Flaccid Paralysis–

17
Q

Why are BoNT clinically useful?

A

Highly specific for neuron receptors and specific to SNARES within neurons only. Many clinical uses for spastic muscles to headaches to other muscular problems. Long Half-life, very long acting treatment.

18
Q

What is the common theme of all Clostridum bacteria?

A

They produce spores that are resistant to environmental stressers and remain inactive for many years.
– Sporulation –