Wadström T, Hisatsune K
Biochem J. 1970 Dec;120(4):725-34. doi: 10.1042/bj1200725.
On cultivation of Staphylococcus aureus in a complex liquid medium, bacteriolytic activity is found extracellularly. The maximal amount was found at the end of the exponential growth phase in batch culture, but in continuous culture run under similar conditions the yield was doubled. Isoelectric focusing of dialysed crude culture supernatants showed that the bacteriolytic activity of all four strains studied (M18, 524, Wood 46 and Duncan) was heterogeneous. The most alkaline peak of activity (isoelectric point 9.5+/-0.1) was assayed against Micrococcus lysodeikticus turbidimetrically. This bacteriolytic activity was purified more than 70-fold after continuous dialysis by adsorption on CM-Sephadex, precipitation with ethanol, heat purification, isoelectric focusing and Sephadex G-100 chromatography. The purified enzyme (isoelectric point 9.6+/-0.1) was found to give a single band on polyacrylamide-gel and cellulose acetate electrophoresis and was devoid of all 14 staphylococcal enzymes and toxins assayed for. The molecular weight is 70000+/-5000 as estimated by Sephadex G-100 and G-200 chromatography. The marked instability of the partially and highly purified enzyme was investigated. The mode of action and some properties of this enzyme are given in the following papers (Wadström & Hisatsune, 1970; Wadström, 1970). These results indicate that this extracellular enzyme which is produced by several strains of S. aureus is not a ;lysozyme' (endo-beta-N-acetylmuramidase) as previously suggested, but an endo-beta-N-acetylglucosaminidase.
在复杂液体培养基中培养金黄色葡萄球菌时，可在细胞外发现溶菌活性。在分批培养的指数生长期结束时发现溶菌活性达到最大值，但在类似条件下进行连续培养时，产量增加了一倍。对透析后的粗培养上清液进行等电聚焦分析表明所研究的所有四株菌株（M18、524、Wood 46和Duncan）的溶菌活性具有异质性。针对溶壁微球菌，通过比浊法测定了活性最强的碱性峰（等电点9.5±0.1）。通过在CM-葡聚糖凝胶上吸附、乙醇沉淀、热纯化、等电聚焦和葡聚糖G-100层析进行连续透析后，这种溶菌活性得到了70多倍的纯化。纯化后的酶（等电点9.6±0.1）在聚丙烯酰胺凝胶电泳和醋酸纤维素电泳中呈现单一谱带，并且在所检测的14种葡萄球菌酶和毒素中均未检出。通过葡聚糖G-100和G-200层析估计其分子量为70000±5000。研究了部分纯化和高度纯化的酶的明显不稳定性。该酶的作用方式和一些特性在以下论文中给出（瓦德斯特伦和久常，1970年；瓦德斯特伦，1970年）。这些结果表明，由几株金黄色葡萄球菌产生的这种细胞外酶并非如先前所认为的是一种“溶菌酶”（内切-β-N-乙酰胞壁酰胺酶），而是一种内切-β-N-乙酰葡糖胺酶。
