Flashcards in (1/15/15) Effects of Antibiotics on Life Cycle of Bacteria (Bailey) Deck (28):
type of antibiotic that actually kills the bacteria
type of antibiotic that prevents bacteria from replicating but does not kill it
_______ antibiotics occur more rapidly than ______ ones
tetracycline is a ______ antibiotic
penicillin is a _____ antibiotic
what are the 4 requirements of an ideal antibiotic
1. broad spectrum of activity
2. would not induce resistance
3. high therapeutic index
4. selective toxicity
is a high or low therapeutic index better for the host?
high (bc it means that you can have a very small, nonleathal dose of antibiotic and it will not kill the host but will kill the bacteria)
to achieve selective toxicity, a microbe must have _____ cell walls and enzyme replication as well as ribosome structure
what are the five ways in which an antibiotic can inhibit bacteria
1. inhibition of cell wall synthesis
2. disruption of cell membrane function
3. inhibition of protein synthesis
4. action as antimetabolites
5. inhibition of nucleic acid synthesis
all penicillins have _____ _____
how does penicillin disrupt cell wall synthesis?
it cause competition for the substrate and also becomes toxic to bacteria in its cleaved form
______ ____ _____ disrupts cell membrane function by binding to phospholipids
polymyxin B sulfate
antibiotic that prevents formation of initiation complex in blockage of the ribosome cycle
antibiotic that blocks tRNA from attaching by binding to 30s subunit in the blockage of the ribosome cycle
antibiotic that blocks elongation but not RNA binding in the blockage of the ribosome cycle
antibiotic that binds to 50s to inhibit chain elongation causing the ribosome to dissociate from RNA in the blockage of the ribosome cycle
what is the only antibiotic that can inhibit DNA replication?
sulfa-drugs are ______
because of the _____ _____ exerted by antibiotics, bacteria have become resistant within one human genome
what are the three steps in the action of antibiotics?
1. drug penetrates the envelope
2. transports into the cell
3. drug binds to target
at which step does resistance to drugs occur?
at all three
what are the three mechanisms of drug resistance?
1. synthesis of enzymes that inactivate the drug
2. prevention of access to the target site
3. modification of the target site
many antibiotics enter the cell through _____
some bacteria develop _____ pumps to pump the antibiotics out of them
efflux (all bacteria have these, just a matter of how strong they are)
what are the three ways that antibiotic resistance spreads?
1. chromosome associated resistance
2. plasmid mediated resistance
3. rapid spread of resistance
what are the three ways to combat an antibiotic resistant pathogen?
failure to eliminate the pathogen could likely increase the likelihood of _______