厌氧乙烷活化关键酶的晶体结构，这一成果由德国马克斯普朗克海洋微生物研究所Tristan Wagner和Gunter Wegener团队经过不懈努力而取得。该研究于2021年7月2日发表于国际一流学术期刊《科学》杂志上。

该课题组研究人员报道了乙烷激活酶的0.99埃分辨率结构，并描述了它与甲烷生成和消耗甲基辅酶M还原酶的具体特征。扩宽的催化室，包含一个二甲基化镍的F430辅助因子，将适应甲基辅酶M还原酶的化学为一个二碳底物。来自蛋氨酸的硫取代来自典型谷氨酰胺的氧作为镍的低轴向配体，这在嗜热的乙烷氧化菌中是保守的特征。

特定的环延长，四分之一螺旋束膨胀，以及翻译后的甲基化导致形成一个33埃长的疏水隧道，引导乙烷到埋藏的活性位点，这已被氙气加压实验证实。

据介绍，乙烷作为海底第二丰富的烃类气体，有效地被厌氧古菌和与其共生的硫酸盐还原菌氧化。

附：英文原文

Title: Crystal structure of a key enzyme for anaerobic ethane activation

Author: Cedric J. Hahn, Olivier N. Lemaire, Jrg Kahnt, Sylvain Engilberge, Gunter Wegener, Tristan Wagner

Issue&Volume: 2021/07/02

Abstract: Ethane, the second most abundant hydrocarbon gas in the seafloor, is efficiently oxidized by anaerobic archaea in syntrophy with sulfate-reducing bacteria. Here, we report the 0.99-angstrom-resolution structure of the proposed ethane-activating enzyme and describe the specific traits that distinguish it from methane-generating and -consuming methyl-coenzyme M reductases. The widened catalytic chamber, harboring a dimethylated nickel-containing F430 cofactor, would adapt the chemistry of methyl-coenzyme M reductases for a two-carbon substrate. A sulfur from methionine replaces the oxygen from a canonical glutamine as the nickel lower-axial ligand, a feature conserved in thermophilic ethanotrophs. Specific loop extensions, a four-helix bundle dilatation, and posttranslational methylations result in the formation of a 33-angstrom-long hydrophobic tunnel, which guides the ethane to the buried active site as confirmed with xenon pressurization experiments.

DOI: 10.1126/science.abg1765

Source: https://science.sciencemag.org/content/373/6550/118