Blundell J K, Perkins H R
J Bacteriol. 1981 Aug;147(2):633-41. doi: 10.1128/jb.147.2.633-641.1981.
Low concentrations of beta-lactam antibiotics caused an increased uptake of radioactive glucosamine into the sodium dodecyl sulfate-insoluble peptidoglycan of growing Neisseria gonorrhoeae. There was no appreciable change in the (small) amount of sodium dodecyl sulfate-soluble polymer present in the cultures. The sodium dodecyl sulfate-insoluble product in control cells was only partially dissolved by egg-white lysozyme (about 40%), but could all be released by the Chalaropsis B muramidase. In cells exposed to beta-lactams the proportion of labeled peptidoglycan susceptible to lysozyme increased to 60%. Examination of the Chalaropsis B digests by thin-layer chromatography showed that they contained disaccharide-peptide monomers with and without O-acetylation and bis-disaccharide-peptide dimers with one or two O-acetyl groups, or with none. beta-Lactam antibiotics caused a decrease in the degree of O-acetylation but did not greatly affect the amount of peptidoglycan cross-linking. They also had the effect of enlarging the bacteria and conserving and thickening the septa that could be observed in thin sections under the electron microscope. The relationship between these results and the effects of beta-lactams on in vitro synthesis of peptidoglycan by ether-treated N. gonorrhoeae is discussed.
低浓度的β-内酰胺抗生素会使放射性葡糖胺更多地摄取到生长中的淋病奈瑟菌的十二烷基硫酸钠不溶性肽聚糖中。培养物中存在的（少量）十二烷基硫酸钠可溶性聚合物没有明显变化。对照细胞中十二烷基硫酸钠不溶性产物仅被蛋清溶菌酶部分溶解（约40%），但可被Chalaropsis B溶菌酶全部释放。在暴露于β-内酰胺的细胞中，易被溶菌酶作用的标记肽聚糖比例增加到60%。通过薄层色谱法对Chalaropsis B消化产物进行检测，结果显示它们含有带或不带O-乙酰化的二糖肽单体、带有一个或两个O-乙酰基团或不带O-乙酰基团的双二糖肽二聚体。β-内酰胺抗生素会使O-乙酰化程度降低，但对肽聚糖交联量影响不大。它们还具有使细菌变大以及保留并加厚在电子显微镜下薄切片中可观察到的隔膜的作用。本文讨论了这些结果与β-内酰胺对经乙醚处理的淋病奈瑟菌肽聚糖体外合成的影响之间的关系。
