ANTIBIOTICS-1

Nota:

• bind to cyto PBP, inh. transpeptidation, inh. cross-linking of bacterial cell wall

1. PENICILLINS, CEPHALOSPORINS,
   1. IMIPENEM, MEROPENEM, ASTREONAM VANCOMYCIN

      Nota:

      • vancomycin - Inhibits peptidoglycan synthases bind to D-Alanine
   2. B-lactamase cleavage of drugs B-lactam ring

1. Interfere with formation of initiation complex
   1. BACTERICIDAL

      Nota:

      • misread genetic code carried by mRNA resulting in the incorperatino of wrong aa
      1. AMINOGLYCOSIDE (30S), LINEZOLID (50S)
         1. production of conjugatingenzymes that increase drugs clearance
2. Interfere with incorporation of next aa
   1. BACTERIOSTATIC

      Nota:

      • inh. insertion of aminoacyl t-RNA into "A" site
      1. TETRACYCLINS (30S), DILFOPRISTIN & QUINUPRISTIN (50S)
         1. production of active transport systems that push drugs out of the cell

            Nota:

            • tetracyclins
3. Interfere with formation of peptide bond
   1. BACTERIOSTATIC

      Nota:

      • inh. peptidyltransferase
      1. CHLORAMPHENICOL
         1. formation of acetylating ensymes that inactivate drugs

            Nota:

            • chloramphenicol
4. Interfere with translocation
   1. BACTERIOSTATIC

      Nota:

      • Inh. translocation of peptidyl-tRNA from acceptor donor site
      1. MACROLIDE (50S), CLINDAMYCIN(50S)
         1. methylation of base in RNA that alter drugs binding

            Nota:

            • macrolides

1. SULFONAMIDE

   Nota:

   • inh. duhydropteroate synthetase
   1. formation of a PABA, increase resistance to inhibition of dihydropteroate synthetase
2. TRIMETHOPRIN & PYRIMETHAMINE

   Nota:

   • inh. dihydrofolate reductase

1. FLUOROQUINOLONES

   Nota:

   • inh. DNA gyrase (topiosomerase 2)
   1. increase transport systems to push drugs out. increase resistance to inh. of topio. 2

      Nota:

      • antibiotic resistance.  R-factor plasmid-mediated transmission. selection of resistance cells 
2. RIFAMPIN

   Nota:

   • inh. DNA-dep RNA polymerase