Major gram - bacteria Flashcards
types of bacteria and characterisiscs
Types bacteria
1) gram +
- purple
2) gram –
- stain pink
- 2 membranes
- LPS outside
flagellum
- called H antigen
- surface antigens used to class different bacteria
- allows bacteria to swim
K antigen
capsule
LPS O antigen use
outer membrane
LPS
- Deter complement proteins (therefore preventing complement cascade and antigens)
- Capsule repels complement proteins or antibodies
gram - cell envolope made of
LPS interacts with the immune system (can be called endotoxin)
Gram - quick summary
- Gram – bacteria have 2 membranes with the OM(outermembrane) connected to LPS layer
- thin peptidoglycan layer (between the membranes)
- do not retain gram stain
- Outer layers and released are LPS major antigens (K H O)
- LPS and Capsule help immune evasion
what type of bacteria is neisseria spp
Gram – diplococci
Common commensals
Pathogenic neissieria speciess
n meningitis
n gonorrhoeae
n meningitis
- meningitis/meningococcal septicaemia
- infection of CSF and meninges
- commensal carriage in pharynx/nasopharyx
what are oligosaccharides good for and found on
invading immune system
gonorrhoea
what can neisseria meningitis/gonorrhoea be grown on
Both fastidious growth (heated blood) + CO2
Nutritionally fussy, have to be grown on blood (dark), due to the iron leaked out as the blood cells have been heated and burst, incubated at 37 degrees
meningitis symptoms
- Rapid onset fever
- dislike to light
- rash (does not blanch when pressed unlike normally)
- stiff neck
- not feeling well
what is meningitis
Inflammation around brain and spinal column (meninges)
how many serogroups does meningitis have and what do these depend on
polysaccharide capsular antigen A B C Y W 135
how does meningitis spread
- Either directly to subarachnoid space
- or through nasopharyngeal mucosa to enter bloodstream
