Scott J F, Kornberg A
J Biol Chem. 1978 May 10;253(9):3292-7.
The product of the rep gene of Escherichia coli catalytically separates phiX174 duplex DNA strands in advance of their replication, utilizing ATP in the process (Scott, J. F., Eisenberg, S., Bertsch, L. L., and Kornberg, A. (1977) Proc. Natl. Acad. Sci. U. S. A. 74, 193-197). The enzyme has now been purified to near-homogeneity. Relatively large quantities were obtained from ColE1-plasmid-containing cells in which the enzyme level was 7 to 10 times above wild type. The assay for rep protein was based on its essential role, with phage-induced cistron A protein, in enzymatic synthesis of phage phiX174 (+) strands, using duplex circular DNA as template. The protein exhibits a molecular weight of 65,000 under denaturing and reducing conditions. The turnover number of the enzyme is approximately 6800 ATP molecules/min in strand separation as measured by extent of replication, or in an uncoupled reaction using single-stranded DNA effector.
大肠杆菌rep基因的产物在phiX174双链DNA复制之前催化其链分离，在此过程中利用ATP（斯科特，J.F.，艾森伯格，S.，伯奇，L.L.，和科恩伯格，A.（1977年）《美国国家科学院院刊》74，193 - 197）。该酶现已纯化至近乎均一。从含有ColE1质粒的细胞中获得了相对大量的该酶，其中酶水平比野生型高7至10倍。rep蛋白的检测基于其与噬菌体诱导的顺反子A蛋白在以双链环状DNA为模板酶促合成噬菌体phiX174（+）链中的关键作用。在变性和还原条件下，该蛋白的分子量为65,000。通过复制程度测量，该酶在链分离中的周转数约为6800个ATP分子/分钟，或者在使用单链DNA效应物的非偶联反应中也是如此。
