M8 Oral Streptococci Flashcards
what is an example of gram +ve aerobic
micrococci
whats an ample of gram +ve anaerobic
peptrococcus
peptostreptococcus
what is an example of facultative gram +ve
catalase +ve - staphylococus
cataras -ve - streptoccuss
what is the largest single group of bacteria isolated from the mouth and can be cultivated from all oral sites
oral streptococci
what do streptococci compromise orally
23% plaque
30% gingival crevice
50% tongue
50% saliva
what are streptococci sep mostly
facultative
little obligate anaerobes
what do stretococci prod in anaerobic condos
lactic acid - reducing potential pH fro demineralisation
what are the 4 main groups of streptococci spp
mutans (alpha) - tooth surface
salivarius (alpha) - tongue
angionosus (beta) - plaque
oralis (alpha) - tooth
what does the 23% of approximal plaque contain
mutans 2%
sanguines 6%
saliavrius 1%
angionosus 0.5%
what is the in silico comparison of genomes
genes can be exchanged including resistance determinants
what does the excnae of genes mean
core genes
shared flowing of genes
abel to take up diff dn
acquire diff features from organisms
hat is alpha haemolysiss
oral streptococci
green (choc)
partial haemolysis (RBA)
what is the beta haemolysis
pathogenic streptococici
clear haemolysis
complete haemolyssi on blood agar
s. progenes
what is gamma haemolyss
no haemolysis
enterococcus faecilis
no haemolysis
on blood agar what does alpha, beta and gamma haemolysis do
alpha - greening of colonies (pneumonia)
beta - clearing, vlanceield, greening
gamma -normal, no haemolysis
what is dental caries
localised dissolution of enamel
may advance to dentine and pulp
common in pits and fissures
accumulation of plaque
what are some sub sp of mutant
s mutans
s sobrinus
s cricetus
what is the mutant group lead to
cause of tooth decay
wide range carbs
how does s mutans do for caries
bind and colonies - extracell polysaccs
prod acid high rate from sugar - acidogenic
tolerate high conc of acid - acidic
what is the most popular carb to use fro carb metab
sucrose
more energy in bond cause more dissolution enamel grow faster
what are virulence factors imp for
colonisation
establish biofilm
acid prod
survival at low pH
what is the oralis group
heterogeneous group of related streptococci
what are some spp of oralis
s oralis s sanguinis s gordonii s mites s crista
what do most of orals group produce
IgA protease
imp virulence factor
what do s sanguines and s gordoniii do
produce extra cell sol and insole gluons
earlycolonisers
what does s sanguinis do
bacterial endocarditis
what does s gordonii do
close to s sanguinis but prod alpha amylase rather than IgA protease
cause infective endocarditis
PadA surface protein - adhesion and interacts with platelet via fibrinogen receptor
what does s mitis do
prefer non jeratinsied in mouth such as cheek
ma cause bacteraemia endocarditis and abscesses
what does s crista do
similar to s sanguinis but with tufts of fibrils on surface
cons cobs
what are the isolation frequency of s sanguines, oralis nd gorfonii
sanguines - 32%
oralis - 30%
gordonii - 13%
other - 5%
what is hermaetogenous spread
distributed by way of blood stream
s gordonii
what is s salivarius
most dom in saliva
prefer keratinsisded statures
not in plaque
how i saivarius beneficial microbe
prod bactericides
assc with infections
what is s vestivularis
non pathogenic
non polysacc prod
what is anginosus group
beta haemolysis
what are the sep of anginosus
s anginosus
s constellates
s inetrmidus
where are a anginsosus
in plaque
isolated form many infections in body
what is s pneumonia
alpa haemolytic
sensitive to optochin
resp pathogen
what si an organism sensitive to bacitracin
s progenies
