Bactericidal synergism between beta-lactams and aminoglycosides: mechanism and possible therapeutic implications

This work, presented as the introductory lecture of the symposium, reviews the mechanisms of antibiotic action of beta-lactams and of aminoglycosides from a historical perspective and gives emphasis to the features relevant to their synergistic interaction. These features include the limiting effect of penetration of aminoglycosides on the rate of killing; the ability of beta-lactams to increase that penetration, even under conditions where they cannot cause a lethal damage to the cell envelope; and the ability of aminoglycosides to be lethal with a smaller amount of cell growth than is required for killing by beta-lactams. The paper also briefly discusses theoretical arguments favoring a broader use of bactericidal synergism in clinical practice.