The biosynthesis of the molybdenum cofactors
The biosynthesis of the molybdenum cofactors
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DOI：
10.1007/s00775-014-1173-y
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发表时间：
2015-03-01
影响因子：
3
通讯作者：
Leimkuehler, Silke
中科院分区：
文献类型：
--
作者：
Mendel, Ralf R.;Leimkuehler, Silke
钼辅因子（Moco）的生物合成是导致钼的生物化学活化的古老、普遍存在且高度保守的途径。Moco是一组氧化还原酶的重要组成部分，这些氧化还原酶在其系统发育分布和结构方面是多样的，无论是在整体水平还是在其催化几何结构方面。这些酶在碳、硫和氮原子上催化各种各样的转化，包括将氧代基团或两个电子转移到底物或从底物转移。迄今已鉴定出50多种辅酶。在除固氮酶以外的所有辅酶中，钼与蝶呤的6-烷基侧链上的二硫杂环戊烯基团配位，称为蝶呤（MPT）。Moco的生物合成可分为三个一般步骤，第四个步骤仅存在于细菌和古细菌中：（1）形成环状吡喃蝶呤一磷酸，（2）形成MPT，（3）将钼插入到异蝶呤中以形成Moco，和（4）在细菌中通过将核苷酸连接到MPT的磷酸基团上对Moco进行额外修饰，形成Moco的二核苷酸变体。本文将重点介绍莫科在细菌、人类和植物中的生物合成。
The biosynthesis of the molybdenum cofactors (Moco) is an ancient, ubiquitous, and highly conserved pathway leading to the biochemical activation of molybdenum. Moco is the essential component of a group of redox enzymes, which are diverse in terms of their phylogenetic distribution and their architectures, both at the overall level and in their catalytic geometry. A wide variety of transformations are catalyzed by these enzymes at carbon, sulfur and nitrogen atoms, which include the transfer of an oxo group or two electrons to or from the substrate. More than 50 molybdoenzymes were identified to date. In all molybdoenzymes except nitrogenase, molybdenum is coordinated to a dithiolene group on the 6-alkyl side chain of a pterin called molybdopterin (MPT). The biosynthesis of Moco can be divided into three general steps, with a fourth one present only in bacteria and archaea: (1) formation of the cyclic pyranopterin monophosphate, (2) formation of MPT, (3) insertion of molybdenum into molybdopterin to form Moco, and (4) additional modification of Moco in bacteria with the attachment of a nucleotide to the phosphate group of MPT, forming the dinucleotide variant of Moco. This review will focus on the biosynthesis of Moco in bacteria, humans and plants.