gram negative Flashcards
what are the 4 main groups of gram negative bacteria?
Proteobacteria
Bacteroids
Chlamydias
Spirochaetes
what shape are proteobacteria
rod (bacilli)
what shape are bacteroids
rod (bacilli)
what shape are chlamydias
round pleimorphic
what shape are Spirochaetes
spiral
what family does enterobacteria belong to?
(these are commonly encountered pathogens)
proteobacteria
what are features of the enterobacteria?
- bacilli
- most are motile
- Facultatively anaerobic - ie. they can grown anaerobically if necessary
what are the 3 main examples of enterobacteria ?
E.Coli
Shigella
salmonella
E.coli
- features
Commensal bacteria
Most abundant facultative anaerobic bacteria in gut
Has peritrichous flagella
E.coli
what infections can it cause?
wound infections eg. following surgery
cystitis (UTIs)
gastroenteritis
‘traveller’s diarrhoea’
Can lead to sepsis
Rare cause of meningitis in infants
shigella
what infections does It cause?
Causes shigellosis infections (bacillary dysentery, severe bloody diarrhoea)
symptoms -
Frequent pass of stools of small volume
Pus and blood, cramps and pain in straining
Fever
shigella
features that make it effective
- shiva toxin
- acid tolerant
- induces apoptosis in macrophages
salmonella
what are the 3 forms of salmonellaosis infection?
Gastroenteritis/enterocolitis( from food poisoning)
Enteric fever aka. typhoid (from poor water quality)
Bacteraemia
BACTEROIDS
- are they aerobic or anaerobic?
- are the commensal flora?
anaerobic
commensal flora in large intestine
opportunistic to tissue injury
CHLAMYDIA
- how do you test for it?
PCR
