MOA and ribosomal units Flashcards
Aminoglycosides
30S
Tetracyclines
30S
Chloramphenicol
50S
Erythromycin
50S
Clindamycin
50S
Linezolid
50S
Telithromycin
50S
Streptogramins
50S
Active against gram-negative rods primarily through binding to PBP3 but not against gram-positive bacteria or anaerobes.
monobactams
first clinically useful monobactam
aztreonam
widest spectrum of b-lactam antibiotics
carbapenems
Directly bind to the d-alanyl-d-alanine portion of the pentapeptide, which blocks the transpeptidation.
* It also inhibits a second enzyme,
transglycosylase.
vancomycin
Prevent the dephosphorylation of the
phospholipid that carries the peptidoglycan subunit across the cell membrane. This blocks the regeneration of the lipid carrier and inhibits cell wall synthesis.
bacitracin
Inhibit cell wall synthesis by inhibiting the
activity of alanine racemase and d-alanyl-d-alanine ligase.
cycloserine
Bind to cell membranes rich in
phosphatidylethanolamine and destroying
membrane functions of active transport and permeability barrier.
polymyxins
Inhibit protein synthesis of bacteria by
attaching to and inhibiting the function of the 30S subunit of the bacterial ribosome.
aminoglycosides
Inhibit the binding of amino-acyl-tRNA to the 30S unit of bacterial ribosomes
tetracyclines
Synthetic analogs of the tetracyclines.
glycylcyclines
attach to a receptor (a 23S rRNA)
on the 50S subunit of the bacterial ribosome. they inhibit protein synthesis by interfering with translocation reactions and the formation of initiation complexes.
macrolides
Resemble erythromycin in mode of action,
antibacterial spectrum, and ribosomal
receptor site but are chemically distinct.
lincosamides
Block the attachment of amino acids to the nascent peptide chain on the 50S unit of ribosomes by interfering with the action of peptidyl transferase.
chloramphenicol
bind to the 23S ribosomal RNA in the 50S
subunit and inhibits protein synthesis.
oxazolidinones
cause premature release of the growing
peptide chain from the 50S ribosomal
subunit.
streptogramins
inhibition of bacterial DNA synthesis by
blocking of DNA gyrase and topoisomerase IV.
quinolones and fluoroquinolones
bind strongly to DNA-dependent RNA
polymerase and thus inhibit RNA synthesis in bacteria.
rifamycins
competitive inhibition of PABA utilization by blocking dihydropteroate synthetase.
sulfonamides
inhibition of dihydrofolate reductase
trimethoprim, pyrimethamine, trimetrexate
Act on mycobacteria by inhibiting the
synthesis of mycolic acids and also by
inhibiting the catalase-peroxidase enzyme.
isoniazid
Act by blocking arabinosyl transferase
thereby inhibiting the synthesis of
arabinogalactan.
ethambutol
Act by inhibiting a fatty acid synthetase that prevents the synthesis of mycolic acid.
Pyrazinamide