Antimicrobial Drugs

  1. Antibiotics
    • A substance produced by a microbe that inhibits the growth of other microbes
    • Most antibiotic-producing microbes have a sporulation process
  2. Antibiotic Sensitivity
    • Sensitivity depends upon:
    • LPS: helps exclude large or hydrophobic molecules
    • Porins: exclude large hydrophobic molecules
    • Antibiotics can inhibit normal intestinal flora
    • Can lead to a proliferation of other microbes
    • Superinfection
  3. Penicillin
    • Penicillin is a Competitve Inhibitor
    • Penicillinase breaks the B-lactam ring
    • Gm- are resistant to Penicillin
  4. Macrolides
    • Block the space (“tunnel”) through which mRNA feeds on ribosome
    • Inhibits protein synthesis
  5. 3. Injury to Plasma Membrane
    • Bacterial division requires elongation of plasma membrane
    • Inhibitors of fatty acid synthesis; inhibits growth
  6. 4. Inhibitors of Nucleic Acid Synthesis
    • DNA or RNA inhibitors
    • The topoisomerase makes it easier for the helicase to go through. Quinolones stop the topoisomerase.
  7. 5. Inhibiting Synthesis of Essential Metabolites
    Usually competitive inhibitors
  8. Drug Resistance
    • 3 categories. Eflux Pump. Every bacteria cell has an eflux pump. It gets in but the pump pumps it back out.
    • Antibiotic degrading enzyme breaks up the antibiotic
    • Antibiotic altering enzyme alters the structure of the antibiotic which makes it useless
  9. Mechanisms of Resistance
    • Enzymatic Destruction or Inactivation of drug
    • Prevention of penetration to target site within microbe
    • Alteration of drug target site (e.g. surface protein)
    • Rapid efflux of antibiotics
Card Set
Antimicrobial Drugs
Svinth Micro quiz