Antimicrobial Agents Flashcards
Describe five mechanisms of bacterial control by antibiotics:
1) inhibiting cell wall synthesis (prevent synthesis of intact peptidoglycan)
2) Inhibiting protein synthesis (selectively inhibit prokaryotic secondary to ribosomal structure)
3) Injuring the plasma membrane (changes permeability of p.m.)
4) Inhibiting nucleic acid synthesis (DNA replication/transcription)
5) Inhibiting synthesis of essential metabolites (prevents enzymatic activity)
Aminoglycosides
Protein synthesis inhibition
Broad spectrum
Changes shape of ribosome (misreading)
Streptomycin
Tetracyclines
Protein synthesis inhibition
Broad spectrum
Tetracycline
Chloramphenicol
Inhibits protein synthesis
Broad spectrum
Inhibits peptide bond
Chloramphenicol
Macrolides
Protein synthesis inhibition (blocks tunnel)
Broad spectrum
Erythromycin
Sulfonamides
Metabolite synthesis inhibitors
Broad spectrum
Trimethoprim - sulfamethoxazole
Cephalosporin
Inhibit cell wall synthesis
Narrow spectrum (extended - some of opposite)
Cephalothin
Penicillin
Inhibit cell wall synthesis - G+ or narrow spectrum
Penicillin G
Polyene antibiotics
Injure plasma membrane
Azoles
Inhibit synthesis of plasma membrane
Griseofulvin
Inhibit mitotic microtubules
What is an opportunistic infection?
An organism that does not normally cause infection, but left unchecked can cause infection/disease.
Describe the modes of action used by antiviral drugs.
Analogs of components of viral DNA/RNA
Describe the mechanisms of drug resistance:
Enzymatic destruction or inactivation of drug
Prevention or penetration to the target site within the microbe
Alteration of the drug’s target site
Rapid efflux of the antibiotic
Variations of mechanisms of resistance
