Yourassowsky E, Van der Linden M P, Lismont M J, Crokaert F, Glupczynski Y
J Antimicrob Chemother. 1985 Jan;15 Suppl A:27-36. doi: 10.1093/jac/15.suppl_a.27.
The effect of a brief beta-lactam action on a bacterial culture has been studied by combining the use of a high performance photometer with phase contrast microscopic examination. After exposure of the culture with the antibiotic, the growth curves presented in logn OD have shown the importance of the pre-lytic increase in OD (PIOD). Using Escherichia coli a study of the PIOD values allowed us to separate the beta-lactam antibiotics studied into two groups: those whose PIOD were concentration-dependent (ampicillin, carbenicillin, ticarcillin, moxalactam, ceftazidime, cefsulodin, cefotaxime) and those whose PIOD were concentration-independent (or weakly dependent) (azlocillin, mezlocillin, piperacillin). When the PIOD was independent of the concentrations, long filaments were observed by phase contrast microscopy. Using Pseudomonas aeruginosa, all the antibiotics studied produced PIOD values that were barely dependent of the concentrations, and long filaments were observed by phase contrast microscopy. Study of the lag of regrowth in the post antibiotic period using a beta-lactamase technique showed that, if the PIOD was hardly concentration dependent, so was the lag of regrowth.
通过结合使用高性能光度计和相差显微镜检查，研究了短暂的β-内酰胺作用对细菌培养物的影响。用抗生素处理培养物后，以对数OD表示的生长曲线显示了OD预裂解增加（PIOD）的重要性。以大肠杆菌为研究对象，对PIOD值的研究使我们能够将所研究的β-内酰胺抗生素分为两组：PIOD呈浓度依赖性的抗生素（氨苄西林、羧苄西林、替卡西林、莫西沙星、头孢他啶、头孢磺啶、头孢噻肟）和PIOD呈浓度非依赖性（或弱依赖性）的抗生素（阿洛西林、美洛西林、哌拉西林）。当PIOD与浓度无关时，通过相差显微镜观察到长丝。以铜绿假单胞菌为研究对象，所有研究的抗生素产生的PIOD值几乎与浓度无关，并且通过相差显微镜观察到长丝。使用β-内酰胺酶技术研究抗生素后时期的再生长延迟表明，如果PIOD几乎不依赖于浓度，那么再生长延迟也是如此。
