Bussiere D E, Bastia D, White S W
Department of Microbiology, Duke University Medical Center, Durham, North Carolina 27710.
Cell. 1995 Feb 24;80(4):651-60. doi: 10.1016/0092-8674(95)90519-7.
The crystal structure of the replication terminator protein (RTP) of B. subtilis has been determined at 2.6 A resolution. As previously suggested by both biochemical and biophysical studies, the molecule exists as a symmetric dimer and is in the alpha + beta protein-folding class. The protein has several uncommon features, including an antiparallel coiled-coil, which serves as the dimerization domain, and both an alpha-helix and a beta-ribbon suitably positioned to interact with the major and minor grooves of B-DNA. A site has been identified on the surface of RTP that is biochemically and positionally suitable for interaction with the replication-specific helicase. Other features of the structure are consistent with the polar contrahelicase mechanism of the protein. A model of the interaction between RTP and its cognate DNA is presented.
已确定枯草芽孢杆菌复制终止蛋白（RTP）的晶体结构，分辨率为2.6埃。正如之前生化和生物物理研究所表明的，该分子以对称二聚体形式存在，属于α + β蛋白折叠类型。该蛋白具有几个不寻常的特征，包括作为二聚化结构域的反平行卷曲螺旋，以及位置合适、可与B - DNA的大沟和小沟相互作用的α螺旋和β折叠带。已在RTP表面鉴定出一个位点，该位点在生化性质和位置上都适合与复制特异性解旋酶相互作用。该结构的其他特征与该蛋白的极性反解旋酶机制一致。本文还展示了RTP与其同源DNA之间相互作用的模型。
