Selected Antibacterial Antimicrobics

SELECTED ANTIBACTERIAL ANTIMICROBICS

Various aspects of the major antimicrobics are now considered in more detail, with emphasis on their modes of action and spectrum. Resistance is mentioned here in the context of spectrum, with mechanisms of resistance. Details on specific an-timicrobic use, dosage, and toxicity should be sought in one of the specialized texts or handbooks written for that purpose.

Antimicrobics That Act on Cell Wall Synthesis

The peptidoglycan (murein sac) component of the bacterial cell wall gives it its shape and rigidity. This giant molecule is formed by weaving the linear glycans N-acetylglucosamine andN-acetylmuramic acid into a basket-like structure. Mature peptidoglycan is held together by cross-linking of short peptide side chains hanging off the long glycan molecules. This cross-linking process is the target of two of the most important groups of antimicrobics, the lactams and the glycopeptides (vancomycin and teicoplanin) (Fig 13 – 1).