[rasheed]

This is commonly asked in USMLE
Here's a quick review:

• Macrolides and Clindamycin ----> blocking the trans-location step of translation (50S subunit); streptogramins may also work on the extrusion of the completed peptide.
• Aminoglycosides ----> Prevent initiation complex by causing misreading of the mRNA code (30S subunit)
• Chloremphenicol and cycloheximides ----> inhibit peptidyl transferase (50S subunit)
• Tetracyclines, Streptogramins, and Linezolid ----> inhibit initiation complex formation by inhibiting the attachment of tRNA to the A site (30S subunit for tetracylin :50S subunit for streptogramins and linezolid)
• Pencillins and cephalosporins ----> bind to PBP and inhibit transpeptidation of the cell wall
• Flouroquinolones ----> inhibit topoisomeras II (DNA gyrase) and topoisomerase IV
• Sulfonamides ----> blocking dihydropterate synthetase
• Trimethoprim and pyrimethamine ----> blocks dihydrofolate reductase
• Vancomycin ----> binds to D-Ala-D-Ala muramyl pentapeptide and halt transglycosylation of the peptidoglycan elongation in bacterial cell wall
• Metronidazole ----> free radicals formation (needs oxygen to work)
• Polymyxins ----> damages the membrane osmotic properties
• INH ----> inhibit synthesis of mycolic acid
• Rifampin ----> works on sigma factor needed for initiation of transcription
• Ethambutol ----> inhibit synthesis of arabinogalactan a cell wall component of mycobacterium
• Puromycin ----> attaches to A site and premature termination of translation

If you know of any high yield antibacterials to be added, please add to the list.

 

[DrSeddik]

This "theme" is so confusing and conflicting, you never get consistent information:

Tetracycline----> attaches to A site in 30s (Thirty) subunit, initiation and elongation inhibition
Linezolid: initiation inhibition through 50s
Streptogramins: as macrolides
Sulfonamides: blocking dihydropterate synthetase only, they act in synergism with Trimethoprim or Pyrimethamine which block DHF reductase.

 

[rasheed]

This "theme" is so confusing and conflicting, you never get consistent information:

Tetracycline----> attaches to A site in 30s (Thirty) subunit, initiation and elongation inhibition
Linezolid: initiation inhibition through 50s
Streptogramins: as macrolides
Sulfonamides: blocking dihydropterate synthetase only, they act in synergism with Trimethoprim or Pyrimethamine which block DHF reductase.

Thanks DrSeddik, I edited the main post to reflect your notes