M14 - biochemistry of plaque Flashcards
define synergistic interactions (beneficial)
- enzymes secreted or released upon lysis can benefit more than one species
- metabolic products can be beneficial to other species
describe quorum sensing
co-ordination of gene expression and developmental pathways
, triggered by sensing the environment including behavious/ amount of other bacteria
what is homofermentation?
bacteria produce one fermentation product
what is heterofermentation?
bacteria produce more than one fermentation product
what bacteria are involved in homolactic fermentation?
Streptococci + lactobacilli –> lactic acid
which bacteria are involved in heterolactic
lactobacilli –> lactic acid and ethanol
mixed acid?
GNABS –> Lactic, acetic, formic acids
which nitrogen source is available as a nutrient source?
salivary proteins/ glycoproteins as nutrient source
what does the production of ammonia do?
counters development of low pH
why are carbohydrates important?
Sucrose promotes Eps
what does bacteriocin do?
it is a substance released by one bacteria that kills another usually by inducing a metabolic block
- substance is normally a protein
what is the product of the degradation of sulphur- containing amino acids?
hydrogen sulphide
vibrios and actinomyces
fusobacterium
when are endotoxins such as Lipopolysaccharides released?
released on death of bacteria
- found on outer membranes of gram -ve cell walls
what are the biological effects of endotoxin such as bacteria?
- fever
- raise capillary permeability
- elicit information
many plaque bacteria release endotoxins also such as
veillonella
bacteriodes
