Mäntsälä P, Suominen I
Acta Chem Scand B. 1981;35(8):567-72. doi: 10.3891/acta.chem.scand.35b-0567.
Beta-lactamase encoded by a plasmid pBR 322 was produced during the active growth phases of Escherichia coli IA 199. The maximal specific activity was about 15 times higher in shock fluid than in the cells disrupted by sonic disintegration. beta-Lactamase activity found in the membrane preparations increased gradually parallel to the cell growth. The amount of beta-lactamase in the membrane fraction, however, was only 0.2-0.4% of that found in shock fluid. beta-Lactamase was purified to homogeneity from shock fluid by a one-step procedure in a DEAE-Sepharose column. Most of the beta-lactamase activity present in the membrane fraction was released by salt extraction. beta-Lactamase solubilized treatment after salt extractions had the same molecular weight and immunological properties as beta-lactamase purified from the periplasmic space. Membrane associated beta-lactamase did not contain any covalently linked phospholipid.
由质粒pBR 322编码的β-内酰胺酶是在大肠杆菌IA 199的活跃生长阶段产生的。休克液中的最大比活性比经超声破碎的细胞中的最大比活性高约15倍。在膜制剂中发现的β-内酰胺酶活性随着细胞生长而逐渐增加。然而，膜部分中β-内酰胺酶的量仅为休克液中发现量的0.2 - 0.4%。通过在DEAE-琼脂糖柱上的一步法从休克液中将β-内酰胺酶纯化至同质。膜部分中存在的大部分β-内酰胺酶活性通过盐提取释放。盐提取后的β-内酰胺酶溶解处理具有与从周质空间纯化的β-内酰胺酶相同的分子量和免疫特性。与膜相关的β-内酰胺酶不含有任何共价连接的磷脂。
