Shockman G D, Kawamura T, Barrett J F, Dolinger D L
Ann Inst Pasteur Microbiol (1985). 1985 Jan-Feb;136A(1):63-6. doi: 10.1016/s0769-2609(85)80023-5.
Streptococcus faecium ATCC 9790 possesses two peptidoglycan hydrolase activities. The first enzyme, an N-acetylmuramoylhydrolase, has been purified and has been shown to be a glucoenzyme. Studies of hydrolysis of soluble, linear uncross-linked peptidoglycan chains showed that the enzyme bound strongly to the non-reducing ends of the chains and then sequentially (processively) hydrolysed susceptible bonds in that chain. The second peptidoglycan hydrolase does not appear to be a glycoprotein and differs from the first enzyme in substrate specificity and mechanism of hydrolysis. The presence of two partially redundant activities which may play different roles in surface growth and division could, at least in part, explain previous difficulties in obtaining mutants which completely lack autolytic activity.
粪肠球菌ATCC 9790具有两种肽聚糖水解酶活性。第一种酶是一种N - 乙酰胞壁酰水解酶，已被纯化并证明是一种糖酶。对可溶性、线性未交联肽聚糖链水解的研究表明，该酶与链的非还原端紧密结合，然后依次（连续地）水解该链中的敏感键。第二种肽聚糖水解酶似乎不是糖蛋白，在底物特异性和水解机制上与第一种酶不同。这两种部分冗余的活性可能在表面生长和分裂中发挥不同作用，这至少可以部分解释以前在获得完全缺乏自溶活性的突变体时遇到的困难。
