Calandra G B, Cole R M
Infect Immun. 1980 Jun;28(3):1033-7. doi: 10.1128/iai.28.3.1033-1037.1980.
Group B streptococci, refractory to previously tested muralysins under physiological conditions, were successfully converted to protoplasts by use of a recently describede N-acetyl muramidase, mutanolysin, derived from a streptomycete. Purified enzyme was effective, but crude preparations, although degrading cell walls, simultaneously produced peculiar effects of cytoplasmic coagulation, retention of cell shape, loss of some intracellular enzymes, and a rise in optical density. Addition of purified mutanolysin to the array of muralysins (group C streptococcal phage-associated lysin, lysozyme), previously successful in preparing protoplasts of different streptococci, now makes possible enzymatic preparation of protoplasts of streptococci of groups A, B, C. D. G, and H.
B组链球菌在生理条件下对先前测试的溶菌酶具有抗性，通过使用一种最近描述的源自链霉菌的N - 乙酰胞壁酸酶——变溶菌素，成功地将其转化为原生质体。纯化的酶是有效的，但粗制品虽然能降解细胞壁，却同时产生了细胞质凝固、细胞形状保持、一些细胞内酶丧失以及光密度增加等奇特效应。将纯化的变溶菌素添加到先前成功制备不同链球菌原生质体的一系列溶菌酶（C组链球菌噬菌体相关溶素、溶菌酶）中，现在使得酶法制备A、B、C、D、G和H组链球菌的原生质体成为可能。
