Microbiology key for correct antibiotic therapy

• antibiotics target key differences between prokaryotes and eukaryotes

• knowledge of individual organisms allows selection of antibiotics before sensitivity testing is completed

• goal of a well-trained physician is to pick antibiotics with the most limited spectrum for likely pathogens

Eukaryotes vs. prokaryotes

• chromosomes: we have multiple; prokaryotes have single

  • DNA gyrases are the targets of drugs such as Ciprofloxacin, which has been hoarded to combat anthrax if necessary

• peptidoglycan in membrane: we don’t have any; prokaryotes do

  • penicillins, cephalosphorins target the linkage of GlcNAc and MurNAc, as described above

• ribosomes: ours are bigger

  • aminoglycosides, macrolides (erythromycin) target bacterial ribosomes

Category: Microbiology Notes