Flashcards in microbiology ch 13, actinomycetes, clostridia, bacillus Deck (17)
2 important genera of actinomycetes?
major component of dental plaque, Femal genital tract
major agent of human actinomycosis, has yellowish sulfur granules, colonies appear as bread crumbs or molars, sensative to penicillin and amoxicillin
where are the infections for israelii usually found?
60-65% are in cervicofacial region
10-20% are abdominal
some are thoracic
cause nocardiosis in humans
clostridia in general
gram positive spore forming bacilli found in soil, water, decaying animal and plants
spores are in soil, vegetative cells in colon and vagina
what does c welchii cause?
gas gangrene, good poisening
what toxin does c welchii make?
alpha toxin- lyses phospholipids of eukaryotic cell membranes
whats the name of the test that uses egg yolk to neutralize the alpha toxin?
Intestinal tract of herbivores, spores in soil, look like drumstick,
c. tetani toxiins
tetanospasmin- potent neurotoxin from vegatative cells
tetanolysin- haemolytic toxin
what do the toxins cause?
trismus( lockjaw), risus sardonicus ( facial muscle spasm), opisthotonos( arching body)
how do the toxins cause these?
blocks inhibitory mediators at spinal synapses
faeces of adults and kids, up to 25% of common antibiotic associated diarrhoea is from C difficile
• spores can survive for years – humans accidental hosts and can cause anthrax
• infection causes septicemia and death