Sargent M G, Ghosh B K, Lampen J O
J Bacteriol. 1968 Oct;96(4):1329-38. doi: 10.1128/jb.96.4.1329-1338.1968.
When protoplasts are prepared from Bacillus licheniformis (strain 749/C, constitutive for penicillinase), approximately 60% of the cell-bound penicillinase is released. The remainder is retained by the protoplast and cannot be removed by washing. This release is specific, in that less than 7% of the cellular reduced nicotinamide adenine dinucleotide (NADH) dehydrogenase and alpha-glucosidase is liberated by the treatment. The freed penicillinase is excluded from G-200 Sephadex, and it is partially sedimented with a force of 65,000 x g for 20 hr. It is probably attached to characteristic tubular and vesicular structures with single-layered membranes that are comparable to structures previously described in intact penicillinase-forming cells. The specific activity of the organelle is more than six times that of twice washed peripheral membrane; furthermore, about 8% of the protein of the structure is penicillinase. At substrate concentrations (benzylpenicillin) of about one-fifth the K(m) value, whole cells show a slight permeability restriction, although this does not occur in isolated particles and protoplasts.
当从地衣芽孢杆菌（749/C菌株，青霉素酶组成型）制备原生质体时，约60%与细胞结合的青霉素酶会被释放出来。其余部分则被原生质体保留，无法通过洗涤去除。这种释放具有特异性，因为该处理释放的细胞内还原型烟酰胺腺嘌呤二核苷酸（NADH）脱氢酶和α-葡萄糖苷酶不到7%。释放出的青霉素酶不能通过G-200葡聚糖凝胶柱，并且在65,000×g的离心力下离心20小时会有部分沉淀。它可能附着在具有单层膜的特征性管状和泡状结构上，这些结构与先前在完整的青霉素酶形成细胞中描述的结构相似。该细胞器的比活性是经过两次洗涤后的外周膜的六倍多；此外，该结构约8%的蛋白质是青霉素酶。在底物浓度（苄青霉素）约为K(m)值的五分之一时，完整细胞表现出轻微的通透性限制，尽管在分离的颗粒和原生质体中不会出现这种情况。
