L12 Flashcards
What factors for bacterial growht rate?
Medium of growth
Temperature
Oxygen
What are the 4 phases exhibited by bacterial growth in a liquid medium?
Lag: Little cell growth as bacteria adjusts to liquid conditions
Exponential: Explosive growth
Stationary: steady state of equal growth and death
Death: death of cells
What do novobiocin and quinolones do as abx?
Inhibit gyrase which is needed for DNA replication in bacteria
What do erythromicin, tetracyclin, streptomycin, spectinomycin do?
Inhibit bacterial ribosome function
How is transcription/translation different in bacteria?
They are coupled -> begin translating mRNA transcript as it is being made
How is peptidoglycan made?
Glycan residues synthesized in bacterial cytoplasm
Transfer across inner membrane into a cut within preexisting peptidoglycan and integrated
What are penicillin binding proteins?
Peptidoglycan biosyntehetic proteins
inhibited by penicillin
What are the major targets of abx?
RNA polymerase
Ribosome
Cell Membrane
Peptidoglycan Synthesis
What are siderophores?
Binds to iron and is excreted by bacteria into environment which can be take up again into bacteria when iron is needed
Sequesters iron
Can be virulent factor
What do bacteria use to clear ROS during respiration?
Peroxidases
SOD
This can also detox host generated ROS aimed at killing pathogen
Where are Type III Secretory Appartus found and what do they do?
Gram Negative Bacteria
Interacts with host cells and penetrates to secrete proteins into cell -> causes pathological events eventually leading to the uptake of bacteria by host cell
