CONTINUOUS ASSOCIATION OF ESCHERICHIA-COLI SINGLE-STRANDED-DNA BINDING-PROTEIN WITH STABLE COMPLEXES OF RECA PROTEIN AND SINGLE-STRANDED-DNA
CONTINUOUS ASSOCIATION OF ESCHERICHIA-COLI SINGLE-STRANDED-DNA BINDING-PROTEIN WITH STABLE COMPLEXES OF RECA PROTEIN AND SINGLE-STRANDED-DNA
复制标题
DOI：
10.1021/bi00355a003
复制
发表时间：
1986-04-08
期刊：
影响因子：
2.9
通讯作者：
COX, MM
中科院分区：
文献类型：
--
作者：
MORRICAL, SW;LEE, J;COX, MM
大肠杆菌（Escherichia coli， SSB）的单链DNA结合蛋白通过促进和稳定recA蛋白与单链DNA （ssDNA）的相互作用，刺激recA蛋白促进的DNA链交换反应。利用SSB的固有色氨酸荧光，在SSB和recA-ssDNA复合物之间检测到atp依赖的相互作用。在最适合DNA链交换的条件下，这种相互作用持续超过1小时。我们的数据表明，当ATP存在时，这种相互作用不涉及SSB对复合体中recA蛋白的显著位移。这种相互作用的性质与其他方法确定的ssb稳定的recA-ssDNA复合物的性质一致。这些数据与SSB在recA-ssDNA复合物形成过程中短暂功能后发生位移的模型不相容。因此，SSB与recA- ssdna复合物的持续结合可能是SSB刺激recA蛋白促进反应机制的一个重要特征。
The single-stranded DNA binding protein of Escherichia coli (SSB) stimulates recA protein promoted DNA strand exchange reactions by promoting and stabilizing the interaction between recA protein and single-stranded DNA (ssDNA). Utilizing the intrinsic tryptophan fluorescence of SSB, an ATP-dependent interaction has been detected between SSB and recA-ssDNA complexes. This interaction is continuous for periods exceeding 1 h under conditions that are optimal for DNA strand exchange. Our data suggest that this interaction does not involve significant displacement of recA protein in the complex by SSB when ATP is present. The properties of this interaction are consistent with the properties of SSB-stabilized recA-ssDNA complexes determined by other methods. The data are incompatible with models in which SSB is displaced after functioning transiently in the formation of recA-ssDNA complexes. A continuous association of SSB with recA-ssDNA complexes may therefore be an important feature of the mechanism by which SSB stimulates recA protein promoted reactions.