Atomic description of an enzyme reaction dominated by proton tunneling
Atomic description of an enzyme reaction dominated by proton tunneling
复制标题
DOI：
10.1126/science.1126002
复制
发表时间：
2006-04-14
期刊：
影响因子：
56.9
通讯作者：
Leys, D
中科院分区：
文献类型：
--
作者：
Masgrau, L;Roujeinikova, A;Leys, D
我们给出了以质子隧穿为主的酶催化反应的原子水平的反应化学描述。通过在近原子分辨率下求解反应中间产物的结构，我们确定了芳香胺脱氢酶氧化色胺的反应途径。结合实验和计算机模拟，我们发现质子转移主要发生在Asp(128)β的氧氧上，该反应以隧穿为主，类似于0.6埃。长程耦合运动在推进隧道施工中的作用存在争议。我们发现，在这个酶系统中，隧道效应是由短距离运动调制的质子-受体距离来促进的，而不需要长距离的耦合运动。
We present an atomic-level description of the reaction chemistry of an enzyme-catalyzed reaction dominated by proton tunneling. By solving structures of reaction intermediates at near-atomic resolution, we have identified the reaction pathway for tryptamine oxidation by aromatic amine dehydrogenase. Combining experiment and computer simulation, we show proton transfer occurs predominantly to oxygen O2 of Asp(128)beta in a reaction dominated by tunneling over similar to 0.6 angstroms. The role of long-range coupled motions in promoting tunneling is controversial. We show that, in this enzyme system, tunneling is promoted by a short-range motion modulating proton-acceptor distance and no long-range coupled motion is required.