CRYSTAL-STRUCTURES OF THE MONOFUNCTIONAL CHORISMATE MUTASE FROM BACILLUS-SUBTILIS AND ITS COMPLEX WITH A TRANSITION-STATE ANALOG
CRYSTAL-STRUCTURES OF THE MONOFUNCTIONAL CHORISMATE MUTASE FROM BACILLUS-SUBTILIS AND ITS COMPLEX WITH A TRANSITION-STATE ANALOG
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DOI：
10.1073/pnas.90.18.8600
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发表时间：
1993-09-15
影响因子：
11.1
通讯作者：
LIPSCOMB, WN
中科院分区：
文献类型：
--
作者：
CHOOK, YM;KE, HM;LIPSCOMB, WN
我们已经解决了分支酸酯的结构（分支酸酯变位酶，EC 5.4.99.5），1.9埃晶体结构的单功能酶从枯草芽孢杆菌。结构测定过程是一个不寻常的，涉及12个单体的酶的不对称单位。用多重同晶置换法结合部分结构相组合和分子平均法求解了该结构。最终的模型，其中包括1380个残基和522个水分子在一个不对称的单位，已被细化为1.9埃，目前的晶体学R值为0.201。B。枯草杆菌分支酸酯是同源三聚体，来自每个单体的β-片层堆积形成假α-桶的核心，在三聚体的外侧具有螺旋。此外，活性位点已被定位通过使用数据从一个复杂的内oxabicyclic抑制剂，模仿反应的过渡态。该复合物的结构已被细化到2.2埃，对于在不对称单元中包括1388个残基、12个抑制剂分子和530个水分子的模型，当前R值为0.182。在每个三聚体中，三个等价的活性位点位于两个相邻亚基的界面处。
We have solved the structure of a chorismate mutase (chorismate pyruvatemutase, EC 5.4.99.5), the 1.9-angstrom crystal structure of the monofunctional enzyme from Bacillus subtilis. The structure determination process was an unusual one, involving 12 monomers of the enzyme in the asymmetric unit. This structure was solved by the multiple isomorphous replacement method with partial structure phase combination and molecular averaging. The final model, which includes 1380 residues and 522 water molecules in an asymmetric unit, has been refined at 1.9 angstrom and the current crystallographic R value is 0.201. The B. subtilis chorismate mutase is a homotrimer, with beta-sheets from each monomer packing to form the core of a pseudo-alphabeta-barrel with helices on the outside of the trimer. In addition, the active sites have been located by using data from a complex with an endo-oxabicyclic inhibitor that mimics the transition state of the reaction. The structure of this complex has been refined to 2.2 angstrom with a current R value of 0.182 for a model that includes 1388 residues, 12 inhibitor molecules, and 530 water molecules in the asymmetric unit. In each trimer, three equivalent active sites are located at the interfaces of two adjacent subunits.