Shiba T, Iwasaki H, Nakata A, Shinagawa H
Department of Experimental Chemotherapy, Osaka University, Japan.
Mol Gen Genet. 1993 Mar;237(3):395-9. doi: 10.1007/BF00279443.
Escherichia coli RuvA and RuvB proteins are encoded by an SOS-regulated operon, which is involved in DNA repair and recombination. RuvB has weak ATPase activity, which is enhanced by the addition of RuvA and DNA, and RuvA and RuvB in the presence of ATP promote branch migration at Holliday junctions. In this work, the physical states of RuvA and RuvB and their interactions with DNA were studied by sedimentation analysis and gel filtration chromatography. RuvA formed a stable tetramer in solution, which resisted dissociation by SDS at room temperature. RuvB formed a dimer in solution. When RuvA and RuvB were mixed, an oligomer complex was formed consisting of a tetrameric form of RuvA and a dimeric form of RuvB, and this complex bound to DNA. The maximal enhancement of the RuvB ATPase activity by RuvA was achieved at this stoichiometry in the presence of excess DNA.
大肠杆菌RuvA和RuvB蛋白由一个受SOS调控的操纵子编码，该操纵子参与DNA修复和重组。RuvB具有微弱的ATP酶活性，添加RuvA和DNA可增强此活性，并且在ATP存在的情况下，RuvA和RuvB可促进霍利迪连接体处的分支迁移。在这项工作中，通过沉降分析和凝胶过滤色谱法研究了RuvA和RuvB的物理状态及其与DNA的相互作用。RuvA在溶液中形成稳定的四聚体，在室温下可抵抗SDS的解离。RuvB在溶液中形成二聚体。当将RuvA和RuvB混合时，会形成一种寡聚体复合物，该复合物由RuvA的四聚体形式和RuvB的二聚体形式组成，并且这种复合物与DNA结合。在过量DNA存在的情况下，在此化学计量比下，RuvA对RuvB ATP酶活性的增强作用达到最大。
