Schumacher M A, Choi K Y, Zalkin H, Brennan R G
Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, Portland 97201-3098.
J Mol Biol. 1994 Sep 23;242(3):302-5. doi: 10.1006/jmbi.1994.1580.
The purine repressor (PurR) is a DNA-binding protein, which together with a purine corepressor serves to regulate de novo purine and pyrimidine biosynthesis in Escherichia coli. PurR belongs to the structurally homologous lac repressor family of transcription regulators. A PurR-hypoxanthine-DNA complex has been crystallized, with DNA encompassing the high affinity purF operator site and which is 16 base-pairs long with 5'-deoxynucleoside overhangs on each complementary strand. The crystals diffract to better than 2.6 A and take the orthorhombic space group C222(1), with unit cell dimensions a = 175.9 A, b = 94.8 A and c = 81.8 A. The structure determination of this PurR-hypoxanthine-DNA complex will provide the first high resolution view of a Lacl member-DNA complex.
嘌呤阻遏蛋白（PurR）是一种DNA结合蛋白，它与嘌呤辅阻遏物共同作用，调节大肠杆菌中嘌呤和嘧啶的从头生物合成。PurR属于转录调节因子中结构同源的乳糖阻遏蛋白家族。PurR-次黄嘌呤-DNA复合物已结晶，DNA包含高亲和力的purF操纵位点，长16个碱基对，每条互补链上有5'-脱氧核苷突出端。这些晶体的衍射分辨率优于2.6 Å，属于正交空间群C222(1)，晶胞尺寸为a = 175.9 Å，b = 94.8 Å，c = 81.8 Å。这种PurR-次黄嘌呤-DNA复合物的结构测定将提供Lacl成员-DNA复合物的首个高分辨率视图。
