Structural Snapshots and Loop Dynamics along the Catalytic Cycle of Glycosyltransferase GpgS
Structural Snapshots and Loop Dynamics along the Catalytic Cycle of Glycosyltransferase GpgS
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DOI：
10.1016/j.str.2017.05.009
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发表时间：
2017-07-05
期刊：
影响因子：
5.7
通讯作者：
Guerin, Marcelo E.
中科院分区：
文献类型：
--
作者：
Albesa-Jove, David;Romero-Garcia, Javier;Guerin, Marcelo E.
糖基转移酶（GT）在自然界中起着重要作用。它们催化糖部分转移到广泛的受体底物。GT是高度选择性的酶，允许识别其糖和受体底物的序列和立体化学中的细微结构差异。我们在这里报告的保留葡糖基-3-磷酸甘油酸合酶（GpgS）的反应中心的一系列结构快照。在这一系列事件中，我们可视化酶如何引导底物进入糖基转移反应发生的反应中心，并揭示了产物释放的机制，不仅涉及底物/产物，而且还涉及酶的多种构象变化。的结构数据进一步补充metadhesics自由能计算，揭示了如何平衡的环路构象调制沿着这些行程。这里报道的信息代表了在分子水平上的GT酶的理解的重要贡献。
Glycosyltransferases (GTs) play a central role in nature. They catalyze the transfer of a sugar moiety to a broad range of acceptor substrates. GTs are highly selective enzymes, allowing the recognition of subtle structural differences in the sequences and stereochemistry of their sugar and acceptor substrates. We report here a series of structural snapshots of the reaction center of the retaining glucosyl-3-phosphoglycerate synthase (GpgS). During this sequence of events, we visualize how the enzyme guides the substrates into the reaction center where the glycosyl transfer reaction takes place, and unveil the mechanism of product release, involving multiple conformational changes not only in the substrates/products but also in the enzyme. The structural data are further complemented by metadynamics free-energy calculations, revealing how the equilibrium of loop conformations is modulated along these itineraries. The information reported here represent an important contribution for the understanding of GT enzymes at the molecular level.