In tube dilution studies, large discrepancies between inhibitory and bactericidal concentrations of BL-P1654 against Pseudomonas were observed. To explain these discrepancies which were not observed with carbenicillin, the kinetics of bacterial killing by these two penicillins were evaluated and compared. The kinetics of bacterial killing by both antimicrobial agents were characteristic of a penicillin, with killing initiating simultaneously with growth. Kill curves revealed the presence of a small number of cells resistant to BL-P1654 which were not detectable macroscopically. Studies on microbial resistance also showed the presence of a small but consistent number of cells resistant to BL-P1654 over a broad range of concentrations above its minimal inhibitory concentration. This pattern of resistance was not observed with carbenicillin. Thus, the discrepancies between inhibitory and bactericidal concentrations of BL-P1654 were not due to any unusual bacteriostatic activity but rather due to a small number of resistant cells whose presence could be detected only by sensitive subculturing techniques.

中文翻译：

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Halomicin，一种新的单孢菌产生的抗生素。

在试管稀释研究中，观察到BL-P1654对假单胞菌的抑制浓度和杀菌浓度之间存在较大差异。为了解释这些差异，而羧苄青霉素没有观察到这种差异，我们评估并比较了这两种青霉素杀死细菌的动力学。两种抗微生物剂杀死细菌的动力学是青霉素的特征，其杀灭与生长同时开始。杀死曲线显示存在少量对BL-P1654有抗性的细胞，这是肉眼无法检测到的。微生物耐药性研究还显示，在高于其最低抑菌浓度的广泛浓度范围内，存在少量但稳定数量的对BL-P1654耐药的细胞。羧苄青霉素未观察到这种耐药模式。从而，