Minami S, Inoue M, Mitsuhashi S
Antimicrob Agents Chemother. 1980 Dec;18(6):853-7. doi: 10.1128/AAC.18.6.853.
A cephalosporin beta-lactamase (cephalosporinase) was extracted from Enterobacter cloacae GN7471 and purified by means of column chromatography. The resulting preparation gave a single protein band upon polyacrylamide gel electrophoresis. The enzyme's isoelectric point was 8.4, and its molecular weight was 44,000. The optimal pH was 8.5, and the optimal temperature was 40 degrees C. The enzyme hydrolyzed cephalosporins much more readily than penicillins. The enzyme activity was inhibited by iodine, semisynthetic penicillins, cefuroxime-type cephalosporins, and cephamycin derivatives. The enzymological properties of the purified enzyme were compared with those of beta-lactamases derived from other gram-negative enteric bacteria.
从阴沟肠杆菌GN7471中提取了一种头孢菌素β-内酰胺酶(头孢菌素酶),并通过柱色谱法进行纯化。所得制剂在聚丙烯酰胺凝胶电泳上呈现单一蛋白条带。该酶的等电点为8.4,分子量为44000。最适pH为8.5,最适温度为40℃。该酶水解头孢菌素比青霉素更容易。该酶的活性受到碘、半合成青霉素、头孢呋辛型头孢菌素和头霉素衍生物的抑制。将纯化酶的酶学性质与源自其他革兰氏阴性肠道细菌的β-内酰胺酶的酶学性质进行了比较。