Crystal structure of Homo sapiens protein hp14.5
Crystal structure of Homo sapiens protein hp14.5
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DOI：
10.1002/prot.10619
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发表时间：
2004-03-01
影响因子：
2.9
通讯作者：
Heinemann, U
中科院分区：
文献类型：
--
作者：
Manjasetty, BA;Delbrück, H;Heinemann, U
结果。与几个同源的YjgF/YER057c/UK114蛋白家族成员一样，人类翻译抑制蛋白HP14。5，采用分支酸变位酶样3，10亚基折叠。每个单体由一个由6链片断和在片面上大致平行排列的两个螺旋形成的球状结构域组成[图1(A)]。在薄片中，从一条边到另一条边的链的顺序是1-2-3-6-4-5，其中4和5是平行的，而所有其他链是反平行的。三个HP14。5个单体缔合成具有三重非晶体对称性的三聚体[图1(B)]。由9个多肽链组成的三个这样的三聚体构成了晶体的不对称单元。3个三聚体的两两叠加产生的均方根值分别为0.399 A、0.607 A和0.556 A，表明三聚体结构密切相关。三聚体的形状像一个三角形的桶。枪管的外表面有三对螺旋，内表面有34股反平行的螺旋。桶的一端被酪氨酸110与3个亚基中的每个亚基密封，另一端被另外3个酪氨酸，酪氨酸32密封。桶的密封导致形成一个充满水分子的大空腔。这个空洞的生物学作用，如果有的话，还不清楚。在外墙的外表面
Results. Like several homologous YjgF/YER057c/UK114 protein family members, the human translational inhibitor protein, hp14. 5, adopts a chorismate mutase-like3, 10 subunit fold. Each monomer consists of one globular domain formed by a 6-stranded-sheet and two-helices arranged in roughly parallel orientation on one side of the sheet [Fig. 1 (a)]. In the-sheet, the order of strands from one edge to the other is 1-2-3-6-4-5, where 4 and 5 are in parallel and all other strands are antiparallel. Three hp14. 5 monomers associate into a trimer with threefold noncrystallographic symmetry [Fig. 1 (b)]. Three such trimers formed by 9 polypeptide chains constitute the asymmetric unit of the crystal. Pairwise superpositions of the 3 trimers yield root-mean-square deviation (RMSD) values of 0.399 A, 0.607 A, and 0.556 A, indicating closely related trimer organization. The shape of the trimer resembles a triangular barrel. Three pairs of-helices are positioned on its outer surface, and 3 4 antiparallel strands form the inner surface of the barrel. The barrel is sealed off at one end by Tyr110 from each of the 3 subunits, and at the other end by 3 other tyrosines, Tyr32. The sealing of the barrel leads to the formation of a large cavity filled with water molecules. The biological role of this cavity, if any, is not clear. On the outer surface of the