title: Lysis enhancement: a novel form of interaction between beta-lactam antibiotics.
abstract: A novel form of synergy has been observed to occur between cephalexin and certain other beta-lactam antibiotics. In the presence of cephalexin a reduction was found in the concentration of other beta-lactam agents needed to induce lysis of Escherichia coli; the effect was particularly marded when cephalexin was allowed to act for a short time before the addition of the second agent. The basis of this type of synergy--which is not likely to be of therapeutic value--is discussed in terms of a theroy perviously put forward, whcih suggests that penicillins and cephalosporins have two distinct sites of action in Gram-negative bacilli.
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001433:Bacteriolysis / Q000187:drug effects*; D002506:Cephalexin / Q000494:pharmacology; D002509:Cephaloridine / Q000494:pharmacology; D002512:Cephalothin / Q000494:pharmacology; D004357:Drug Synergism; D004926:Escherichia coli / Q000187:drug effects*; D009391:Nephelometry and Turbidimetry; D010403:Penicillin Resistance; D047090:beta-Lactams / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D000667:Ampicillin; D002509:Cephaloridine; D002506:Cephalexin; D002512:Cephalothin