Lecture 3 Flashcards
bacteria cell about ____ diameter
2 micron
why does size matter?
high SA/V ratio so nutr. and waste move efficiently in and out (rapid growth); large # can occupy small space
location of gene material?
cytoplasm
what cell biochem rxns happen in cytoplasm?
nutr. storage, protein synth, biosynth enzymes
significance of cell envelope?
structure, staining rxn, unique chem comps, target of anti-microbe chem, interface cell and enviro (pathogenicity)
gram neg. has ____ prptidoglycan, while positive has __
thin (7-8nM); thick (80-100nM)
gram ___ has no outer mem
positive
function of plasma membrane? (inner)
permeability barrier, metabolic proteins (energy, biosynth, transport)
peptidoglycan consist of :
2 CHO units and four amino acids–?linked to make chains, which join to make mesh
purpose of PG?
structure, strength, rigidity, protect
PG broken by:
lysozyme
how lysozyme cleave?
cleave bond tween NAG and NAM
lysozyme found in human ____ for what reason?
secretory fluids; innate defense
what drug interfere with bacteria able form PG?
penicillin
gram rxn due to:
thickness of PG
what’s in outer mem (gram neg)
phospholipid bilayer, lipopolysaccharide
what is point of LPS?
protective
structure of LPS?
3-part lipid and CHO, partly buried in OM via lipd A group
LPS also known as ___
endotoxin (important in disease)
what is a pyrogenic agent?
anything induce fever (like LPS )
how come mycobacterium tuberculosis is weird?
envelope has inner mem+PG+mycolic acid outer layer
what is mycolic acid?
long chain waxy f.a. , resistant to lots of stuff
why is mycoplasma weird?
no outer mem or PG (just single phospholipid mem containing sterols for stability)–>very fragile, no consistent shape
what does mycoplasma pneumonia cause?
atypical/walking pneumonia (long term)
