Kiener A, König H, Winter J, Leisinger T
J Bacteriol. 1987 Mar;169(3):1010-6. doi: 10.1128/jb.169.3.1010-1016.1987.
The pseudomurein-degrading enzyme from autolysates of Methanobacterium wolfei was purified approximately 500-fold to electrophoretic homogeneity by ion-exchange chromatography under anaerobic conditions. Analysis of the soluble cell wall fragments produced by the pure enzyme from a cell wall preparation of M. thermoautotrophicum indicated that it is a peptidase hydrolyzing the epsilon-Ala-Lys bond of pseudomurein. A partially purified preparation of pseudomurein endopeptidase was free of nuclease activity and thus proved useful for the preparation in high yields of undegraded chromosomal and plasmid DNA from M. thermoautotrophicum. The partially purified enzyme was also used for the preparation of protoplasts, which were stabilized by 0.8 M sucrose. Under growth conditions the protoplasts produced methane and increased up to 100-fold in size, but failed to regenerate a cell wall.
在厌氧条件下，通过离子交换色谱法将沃氏甲烷杆菌自溶物中的假肽聚糖降解酶纯化了约500倍，达到电泳纯。对该纯酶作用于嗜热自养甲烷杆菌细胞壁制剂所产生的可溶性细胞壁片段的分析表明，它是一种肽酶，可水解假肽聚糖的ε-丙氨酸-赖氨酸键。部分纯化的假肽聚糖内肽酶制剂无核酸酶活性，因此被证明可用于高产制备嗜热自养甲烷杆菌未降解的染色体DNA和质粒DNA。该部分纯化的酶还用于制备原生质体，原生质体用0.8M蔗糖稳定。在生长条件下，原生质体产生甲烷，大小增加至100倍，但未能再生细胞壁。
