Structural and Computational Bases for Dramatic Skeletal Rearrangement in Anditomin Biosynthesis
Structural and Computational Bases for Dramatic Skeletal Rearrangement in Anditomin Biosynthesis
复制标题
DOI：
10.1021/jacs.8b06084
复制
发表时间：
2018-08-01
影响因子：
15
通讯作者：
Abe, Ikuro
中科院分区：
文献类型：
--
作者：
Nakashima, Yu;Mitsuhashi, Takaaki;Abe, Ikuro
AndA 是一种 Fe(II)/α-酮戊二酸 (α KG) 依赖性酶，是通过催化连续脱氢和异构化反应构建 Anditomin (1) 独特且拥挤的桥环系统的关键酶。尽管我们之前在一定程度上表征了 AndA，但该酶促进这种剧烈结构重建的方式仍然难以捉摸。在这项研究中，我们解析了 AndA 的三种 X 射线晶体结构，包括其 apo 形式以及与 Fe(II)、α KG 和两种底物的复合物。晶体结构和突变实验确定了几个对催化很重要的关键氨基酸残基，并深入了解 AndA 如何控制反应。此外，计算计算验证了所提出的桥环形成反应机制，并揭示了转化过程中一系列构象变化的要求。
AndA, an Fe(II)/alpha-ketoglutarate (alpha KG)-dependent enzyme, is the key enzyme that constructs the unique and congested bridged-ring system of anditomin (1), by catalyzing consecutive dehydrogenation and isomerization reactions. Although we previously characterized AndA to some extent, the means by which the enzyme facilitates this drastic structural reconstruction have remained elusive. In this study, we have solved three X-ray crystal structures of AndA, in its apo form and in the complexes with Fe(II), alpha KG, and two substrates. The crystal structures and mutational experiments identified several key amino acid residues important for the catalysis and provided insight into how AndA controls the reaction. Furthermore, computational calculations validated the proposed reaction mechanism for the bridged-ring formation and also revealed the requirement of a series of conformational changes during the transformation.