Elliott T S, Greenwood D, Rodgers F G, O'Grady F
Br J Exp Pathol. 1979 Feb;60(1):14-23.
The response to benzylpenicillin of 2 strains of Staphylococcus aureus was investigated in vitro using 3 techniques in parallel: continuous turbidimetric monitoring, continuous microscopic monitoring, and thin-section electron microscopy. Cultures of staphylococci were exposed to several concentrations of penicillin for various intervals of time before terminating the antibiotic activity with penicillinase. Bacterial lysis by penicillin was concentration-dependent and showed an optimal dosage effect which was very marked for one of the strains. The growth and division of cells continued for up to 1 h in the presence of penicillin. A variety of morphological responses was observed at each penicillin concentration. These changes ranged from complete bacterial lysis to apparently normal cells, and included several different types of aberrant morphological forms. On addition of penicillinase to cultures exposed to penicillin, there was a time interval before survivors began to divide. This period was increased by raising the concentration of penicillin or by increasing the period of exposure to penicillin. Bacteria resuming growth after surviving penicillin action exhibited markedly aberrant septation. Most of the survivors were found to originate from clumps of cocci rather than from individual cells or small groups.
采用连续比浊监测、连续显微镜监测和超薄切片电子显微镜这3种技术，对2株金黄色葡萄球菌对苄青霉素的体外反应进行了研究。在以青霉素酶终止抗生素活性之前，将葡萄球菌培养物暴露于几种浓度的青霉素中不同时间间隔。青霉素引起的细菌裂解呈浓度依赖性，并显示出最佳剂量效应，其中1株菌的该效应非常显著。在青霉素存在的情况下，细胞的生长和分裂可持续长达1小时。在每个青霉素浓度下均观察到多种形态学反应。这些变化范围从完全细菌裂解到看似正常的细胞，包括几种不同类型的异常形态形式。向暴露于青霉素的培养物中添加青霉素酶后，存活菌开始分裂前存在一个时间间隔。通过提高青霉素浓度或增加暴露于青霉素的时间，该时间段会延长。在青霉素作用下存活后恢复生长的细菌表现出明显异常的隔膜形成。发现大多数存活菌源自球菌团块，而非单个细胞或小群体。
