beta-lactam inhibits the cross link between peptidoglycan
between NAM and NAG in the bacterial cell wall
the bete-lactam ring binds with the enzyme
that produces these linkages
the enzyme that hydrolises
these bonds continue to work
making the cell wall weak, the
osmotic pressure will continue
to rise eventually causing the
cell to burst and die
Blocks the division of the bacteria
usually on gram positive as there is a single cell wall
Target Ribosomes
targets protein synthesis
Streptomycin
cannot be administered orally but instead
by regular intramuscular injections
binds to the 30s subunits of the bacterial
ribosome, this misleads the DNA codon
eventually causing inhibition of protein
synthesis
by binding to the 30s subunit it interferes with the 50s subunit whcih associates with
mRNA. as a result an unstable mRNA strand is produced meaning the incorect AA
acids are coded for and therefore the worn proteing are produced causing cell death
can be used on both gran negative
and positive making it a broad
spectrum antibiotic
bacterial ribosomes are different than that of
humans meaning that it has specific toxicity
Inhibit Nucleic Acid Synthesis
Qunilones
broad spectrum
prevent DNA from unwinding and duplicating
targets DNA gyrasa (topoisomerase) which causes
the DNA to unwind during DNA replication.
used to treat certain infections (UTIs) caused by gram negative bacteria
enter cells via pores therefore often
used to treat intracellular infections
Anti-metabolites
Sulfonamides
humans require folic acid but the get it through diet and
we do not synthesis it therefor this is effective against
organismis that rely on folic acid synthesis
selective toxicity
competitive inhibition of
dihydropterate synthetase (DHPS)
DHPS catalyses tconversion of PABA to
dihydropterate in folate synthesis pathway
inhibit the production of folic acid an important metabolite
in DNA synthesis therefor cells are unable to divide
inhibits the use of a metabolite which is part of normal metabolism
can have a toxic effect on cells such as halt
growth and cell division (sometimes used in
cancer treatments)