Orchestration of diverse components in soluble methane monooxygenase for methane hydroxylation  

可溶甲烷单氧酶中不同组分对甲烷羟基化的协调作用

作　　者：Yunha Hwang Dong-Heon Lee Seung Jae Lee Yunha Hwang;Dong-Heon Lee;Seung Jae Lee(全北国立大学化学系,韩国;全北国立大学分子生物学与遗传学研究所,韩国)

机构地区：[1]Department of Chemistry,Jeonbuk National University,Jeonju 54896,Korea [2]Research Institute for the Molecular Biology and Genetics,Jeonbuk National University,Jeonju 54896,Korea

出　　处：《Chinese Journal of Catalysis》2025年第1期204-212,共9页催化学报(英文)

摘　　要：Methane(CH_(4))has a higher heat capacity(104.9 kcal/mol)than carbon dioxide(CO_(2)),and this has inspired research aimed at reducing methane levels to retard global warming.Hydroxylation under ambient conditions through methanotrophs can provide crucial information for understanding the harsh C-H activation of methane.Soluble methane monooxygenase(sMMO)belongs to the bacterial multi-component monooxygenase superfamily and requires hydroxylase(MMOH),regulatory(MMOB),and reductase(MMOR)components.Recent structural and biophysical studies have demonstrated that these components accelerate and retard methane hydroxylation in MMOH through protein-protein interactions.Complex structures of sMMO,including MMOH-MMOB and MMOH-MMOD,illustrate how these regulatory and inhibitory components orchestrate the di-iron active sites located within the four-helix bundles of MMOH,specifically at the docking surface known as the canyon region.In addition,recent biophysical studies have demonstrated the role of MmoR,aσ54-dependent transcriptional regulator,in regulating sMMO expression.This perspective article introduces remarkable discoveries in recent reports on sMMO components that are crucial for understanding sMMO expression and activities.Our findings provide insight into how sMMO components interact with MMOH to control methane hydroxylation,shedding light on the mechanisms governing sMMO expression and the interactions between activating enzymes and promoters.CH_(4)的热容(104.9kcal/mol)高于CO_(2),因此降低CH_(4)排放以减缓全球变暖成为研究热点。在环境条件下,甲烷氧化菌能够羟基化甲烷,这为研究甲烷中强C-H键的活化提供关键信息.可溶性甲烷单加氧酶(sMMO)属于细菌多组分单加氧氧酶超家族,包括羟化酶(MMOH)、调节酶(MMOB)和还原酶(MMOR)三个组分.近期的结构和生物物理研究表明,这些组分通过蛋白质相互作用可以加速或延缓MMOH中的甲烷羟基化过程.SMMO具有MMOH-MMOB和MMOH-MMOD等复杂结构,通过研究其中的调节和抑制成分,可以理解它们如何协调位于MMOH四螺旋束内的二铁活性位点,尤其有助于理解这些活性位点如何影响对接表面上的峡谷区域.此外,最近的生物物理研究已经证明了MmoR(一种54依赖性转录调节因子)在调节sMMO表达模式中的重要作用.本综述文章概述了近期关于sMMO研究的最新成果,这些成果对于深入理解sMMO的表达模式和功能活动至关重要.文章详细揭示了sMMO组分如何与MMOH相互作用,从而调控甲烷的羟基化过程,并阐明了调控sMMO表达的内在机制以及激活酶与启动子之间的相互作用关系.

关 键 词：Soluble methane monooxygenase Non-hemedi-ironactivesite Methane oxidation C-Hactivation O_(2)activation 

分 类 号：O64[理学—物理化学]