A catalytically versatile benzoyl-CoA reductase, key enzyme in the degradation of methyl- and halobenzoates in denitrifying bacteria
作者:Oliver Tiedt、Jonathan Fuchs、Wolfgang Eisenreich、Matthias Boll
DOI:10.1074/jbc.ra118.003329
日期:2018.6
Class I benzoyl-CoA (BzCoA) reductases (BCRs) are key enzymes in the anaerobic degradation of aromatic compounds. They catalyze the ATP-dependent reduction of the central BzCoA intermediate and analogues of it to conjugated cyclic 1,5-dienoyl-CoAs probably by a radical-based, Birch-like reduction mechanism. Discovered in 1995, the enzyme from the denitrifying bacterium Thauera aromatica (BCRTar) has
I类苯甲酰辅酶A(BzCoA)还原酶(BCR)是芳香族化合物厌氧降解的关键酶。他们可能通过基于自由基的,类似桦木的还原机制催化中央BzCoA中间体及其类似物向ATP依赖性还原成共轭环状1,5-二烯酰基-CoA。于1995年发现的反硝化细菌芳香龙虾(BCRTar)的酶至今仍是唯一分离出的且可从生物化学途径获得的BCR,主要是因为BCR极不稳定,并且迄今为止其异源生产已大大失败。这里,我们描述了一个平台,用于从大肠杆菌中的相关反硝化物种Thauera chlorobenzoica(MBRTcl)编码指定的3-甲基苯甲酰辅酶A还原酶的四个结构基因的异源表达。有人建议参与降解甲基取代的BzCoA类似物。重组的MBRTcl具有一个αβγδ亚基结构,包含三个低电势[4Fe-4S]簇,并且高度不稳定。它催化了BzCoA的ATP依赖性还原脱芳香化反应,每转移两个电子就水解2.3-2.8个ATP,并优先在间