- Antibiotics
- Antibiotics
- Inhibit wall synthesis
- Beta lactams (penicillins, monobactams, cephalosporins, carbopenams)
- Carbopenams have the best cover of the β lactams
- Cephalosporins
- Similar to penicillins but have a β lactam ring fused to a dihydrothiazine ring instead of a thiazolidine ring
- Subsequent generations have increasing gram -ve cover and better penetration into the CNS.
- Glycopeptides
- Inhibit glycopeptide synthetase, have good gram +ve cover.
- Vancomycin, teicoplanin
- Vancomycin is not obsobed by the enteral route so is used in CDT
- Inhibit bacterial protein synthesis
- Aminoglycosides
- Inhibit 30s ribosomal subunit
- Chloramphenicol
- Clindamycin
- Inhibits ribosomal translocation
- Fusidic acid
- Prevents turnover of elongation factor G from ribosome
- Macrolides
- Bind to 50s ribosomal unit
- Tetracyclines
- Prevent tRNA binding to ribosome
- Inhibit nucleus acid synthesis
- Metronidazole
- Nitrofurantoin
- Quinolones
- Inhibit alpha subunit of DNA gyrase so inhibits supercoiling
- Rifampicin
- Inhibits DNA-dependent RNA polymerase
- Sulphonamides
- Inhibits dihydropteroate synthetase (DHPS)
- Bacterial resistance
- Bacteria can produce β lactamase or penicillinase acquired by plasmid transfer
- Bacteria can produce penicillin binding proteins eg MRSA
- MRSA is resistant to all β lactams therefore vancomycin is often used
- Others
- Gram negative
- Thin cell wall which stains pink
- Cocci
- Bacilli
- Enterobacteria
- Pseudomonas
- Campylobacter
- Spirochetes
- Intracellular
- Gram positive
- Thick cell wall which stains purple
- Cocci
- Staphylococcus
- Streptococcus
- Bacilli
- Fillamentous