Anaerobes Flashcards
Where do obligate anaerobes derive their nutrients?
ATP from fermentation
What is fermentation? is it efficient?
produces organic acids, alcohols, or solvents as waste products.
Why can’t obligate anaerobes live in an oxygen atmosphere?
They lack the enzymes
Give examples of enzymes that aerobes would use
catalase, superoxide dismutase, peroxidase
What are anaerobic pathogens?
Normal flora that escape their proper compartment or soil organisms that enter body through wounds or through consumption of vacuum packed food.
What is special about culturing anaerobes?
Require special techniques
What techniques are required for culturing anaerobes?
growth and sometimes all handling must happen under anoxic conditions.
How do you treat liquid media?
with reducing agents and tightly stoppered in fully gilled container
How do you trear agar plates>
must be incubated in an anaerobic culture jar
How must very sensitive anaerobes be handled?
within an anaerobic glove box
How do you identify unknown anaerobes?
May be identified by gram stain and biochemical tests and/or gas chromatography to analyze their fermentation products
What are the major pathogenic anaerobes?
clostridium, GNAB, and actinomyces
Which of the major pathogens are gram (+)
Clostridia and actinomyces
Which of the major pathogens are normal flora?
GNAB, actinomyces, and Clostridium difficile are normal flora
How do the other pathogens infect their hosts?
the rest of the clostridia depends on their spore forming ability to jump into humans.
Describe anaerobic virulence
determined by exotoxin
What are some of the diseases produced by anaerobic bacteria exotoxin
Tetanus and botulism result from neurotoxin production; gas gabgrene and abcess formation depend on tissue-degrading enzymes
How are anaerobic infections treated?
Antibiotics (as concluding step)
How are abscess diseases treated?
begins with surgical care (draining and debriding)
How are toxigenic diseases treated?
Antitoxin administered
