Structure of the LarB-Substrate Complex and Identification of a Reaction Intermediate during Nickel-Pincer Nucleotide Cofactor Biosynthesis.

ABSTRACT: LarB catalyzes the first step of biosynthesis for the nickel-pincer nucleotide cofactor by converting nicotinic acid adenine dinucleotide (NaAD) to AMP and pyridinium-3,5-biscarboxylic acid mononucleotide (P2CMN). Prior studies had shown that LarB uses CO₂ for substrate carboxylation and reported the structure of a Lactiplantibacillus plantarum LarB·NAD⁺ complex, revealing a covalent linkage between Cys221 and C4 of the pyridine ring. This interaction was proposed to promote C5 carboxylation, with C5-carboxylated-NaAD suggested to activate magnesium-bound water, leading to phosphoanhydride hydrolysis. Here, we extended the analysis of wild-type LarB by using ultraviolet-visible spectroscopy to obtain additional evidence for cysteinyl side chain attachment to th

SUBMITTER: Chatterjee S 

PROVIDER: S-EPMC10842510 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature