Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
Institute of Life Sciences, Université catholique de Louvain, B-1348 Louvain-La-Neuve, Belgium.
Curr Opin Chem Biol. 2018 Dec;47:18-23. doi: 10.1016/j.cbpa.2018.06.019. Epub 2018 Jul 9.
A novel organometallic cofactor, nickel pyridinium-3,5-dithiocarboxylic acid mononucleotide, was recently discovered in lactate racemase (LarA) of Lactobacillus plantarum. This review summarizes the substantial progress made in uncovering the function of this cofactor as a transient hydride acceptor in the LarA mechanism. The latest developments related to cofactor biosynthesis reveal insights into a pathway in which LarB serves as a nicotinic acid adenine dinucleotide hydrolase/carboxylase, LarE acts as a sacrificial sulfur transferase, and LarC functions as a nickel insertase, forming the nickel-pincer nucleotide cofactor that becomes covalently tethered to LarA in some bacteria. Bioinformatic studies reveal a widespread occurrence of larA, larB, larC, and larE orthologs in microorganisms, and additional roles for the cofactor are considered.
最近在植物乳杆菌的乳酸消旋酶（LarA）中发现了一种新型的有机金属辅因子，镍吡啶-3,5-二硫代羧酸单核苷酸。本综述总结了在揭示该辅因子作为 LarA 机制中瞬态氢化物受体的功能方面所取得的重大进展。与辅因子生物合成相关的最新进展揭示了 LarB 作为烟酰胺腺嘌呤二核苷酸水解酶/羧化酶、LarE 作为牺牲硫转移酶、LarC 作为镍插入酶的途径，形成镍钳核苷酸辅因子，在某些细菌中与 LarA 共价连接。生物信息学研究表明，在微生物中广泛存在 larA、larB、larC 和 larE 的同源物，并且考虑了该辅因子的其他作用。
