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通过在蓝色琼脂糖凝胶上进行亲和层析从纤维链霉菌中纯化β-内酰胺酶。

Purification of beta-lactamase from Streptomyces cellulosae by affinity chromatography on Blue Sepharose.

作者信息

Ogawara H, Horikawa S

出版信息

J Antibiot (Tokyo). 1979 Dec;32(12):1328-35. doi: 10.7164/antibiotics.32.1328.

Abstract

A beta-lactamase from culture supernatant of Streptomyces cellulosae was purified about 1,450-fold to apparent homogeneity in polyacrylamide gel electrophoresis and isoelectric focusing on polyacrylamide gel sheet. The methods used were ammonium sulfate precipitation, CM-52 cellulose ion-exchange chromatography and affinity chromatography on Blue Sepharose CL-6B. The molecular weight was determined to be approximately 27,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This value was in good agreement with the previous value determined by gel filtration on Sephadex G-75. The isoelectric point was pH 9.5. The enzyme behaved primarily as penicillinase and apparent Km value for benzylpenicillin was 500 microM. The beta-lactamase of S. cellulosae interacted strongly with blue dextran and NADP+-agarose but not with Sepharose. In addition, the presence of NADP+ but not NAD+ and ATP diminished sharply the intrinsic fluorescence intensity of the enzyme and the apparent association constant was calculated to be 1.4 x 10(3) M-1. The beta-lactamase decreases its enzymatic activity against benzylpenicillin in the presence of NADP+. From these results, it is suggested that this beta-lactamase has a dinucleotide binding fold.

摘要

从纤维链霉菌培养上清液中纯化出一种β-内酰胺酶,通过聚丙烯酰胺凝胶电泳和聚丙烯酰胺凝胶薄板等电聚焦,该酶被纯化了约1450倍,达到表观均一性。所采用的方法包括硫酸铵沉淀、CM - 52纤维素离子交换色谱和Blue Sepharose CL - 6B亲和色谱。通过十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳测定其分子量约为27,000。该值与先前通过Sephadex G - 75凝胶过滤测定的值非常一致。其等电点为pH 9.5。该酶主要表现为青霉素酶,对苄青霉素的表观Km值为500μM。纤维链霉菌的β-内酰胺酶与蓝色葡聚糖和NADP⁺-琼脂糖强烈相互作用,但与琼脂糖不相互作用。此外,NADP⁺的存在而非NAD⁺和ATP会使该酶的固有荧光强度急剧降低,计算得到的表观缔合常数为1.4×10³ M⁻¹。在NADP⁺存在的情况下,该β-内酰胺酶对苄青霉素的酶活性降低。从这些结果表明,这种β-内酰胺酶具有二核苷酸结合结构域。

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