Function of nucleoside triphosphate and polynucleotide in Escherichia coli recA protein-directed cleavage of phage lambda repressor.
Function of nucleoside triphosphate and polynucleotide in Escherichia coli recA protein-directed cleavage of phage lambda repressor.
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DOI：
10.1016/s0021-9258(18)43384-4
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发表时间：
1981-08
期刊：
影响因子：
--
通讯作者：
N. Craig;Jeffrey W. Roberts
中科院分区：
文献类型：
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作者：
N. Craig;Jeffrey W. Roberts
当大肠杆菌recA蛋白与单链多核苷酸和三磷酸核苷相互作用激活时，它在体外催化抑制物的特异性蛋白水解裂解。ATP类似物腺苷-5'- o -（3-硫代三磷酸）（ATP γ S）满足NTP要求。我们在这里表明，尽管ATP γ S在抑制物裂解中具有活性，但它被recA蛋白dna依赖性核苷三磷酸酶活性水解的速率可以忽略不计。在DNA存在的情况下，ATP γ S与recA蛋白紧密结合在一个复合体中，这个复合体可以被检测到，因为它被硝化纤维素过滤器捕获。每个recA单体结合一个ATP S分子。这些结果表明，recA蛋白、DNA和三磷酸核苷的三元复合物是抑制物裂解的活性物质。recA蛋白的激活由小的，明确的寡核苷酸在DNA的地方被描述和表征。
Escherichia coli recA protein catalyzes a specific proteolytic cleavage of repressors in vitro when it is activated by interaction with a single-stranded polynucleotide and nucleoside triphosphate. The ATP analogue adenosine-5'-O-(3-thiotriphosphate) (ATP gamma S) satisfies the NTP requirement. We show here that despite its activity in repressor cleavage, ATP gamma S is hydrolyzed at a negligible rate by the recA protein DNA-dependent nucleoside triphosphatase activity. In the presence of DNA, ATP gamma S binds tightly to recA protein in a complex that can be detected because it is trapped by a nitrocellulose filter. One ATP gamma S molecule is bound per recA monomer. These results suggest that a ternary complex of recA protein, DNA, and nucleoside triphosphate is the species active in repressor cleavage. The activation of recA protein by small, defined oligonucleotides in place of DNA is described and characterized.