文献类型：期刊文献

英文题名：Biochemical and structural characterization of a novel nicotinamide mononucleotide adenylyltransferase from thermophilic fungi Chaetomium thermophilum

作者：Qian, Xiao-Long[1,3];Li, Jia-Yi[1];Li, Chun-Xiu[1,2];Pan, Jiang[1,2];Mu, Bozhong[1,2];Xu, Jian-He[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Shanghai Collaborat Innovat Ctr Biomfg, 130 Meilong Rd, Shanghai 200237, Peoples R China;[3]Suzhou Bioforany EnzyTech Co Ltd, 8 Yanjiuyuan Rd,Econ Dev Zone, Changshu 215512, Jiangsu, Peoples R China

年份：2025

卷号：776

外文期刊名：BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:001511816200001)】；

基金：This work was financially supported by the National Natural Science Foundation of China (22478116 & 32471495) , the National Key R & D Program of China (2024YFA0917800) , and the Fundamental Research Funds for the Central Universities (22221818014) .

语种：英文

外文关键词：Nicotinamide mononucleotide adenylyltransferase; Crystal structure; Characterization; Chaetomium thermophilum; NAD(+) synthesis

摘要：Nicotinamide mononucleotide adenylyltransferases (NMNAT EC: 2.7.7.1) play pivotal roles in synthesis of nicotinamide adenine dinucleotide (NAD(+)) through catalyzing the reaction of nicotinamide mononucleotide (NMN) with adenosine triphosphate (ATP). To date, multiple crystal structures of NMNAT originated from bacteria, archaea, and eukaryote have been resolved. However, none structure of NMNAT from thermophilic fungi was elucidated. Here we report the structure of nicotinamide mononucleotide adenylyltransferase (CtNMNAT) from thermophilic fungi Chaetomium thermophilum at a resolution of 2.10 angstrom. The enzyme crystals were in space group of P2(1)2(1)2(1) with two monomers per asymmetric unit. A nicotinamide mononucleotide (NMN) molecule was identified in the active pocket. Enzyme activity assays confirmed that CtNMNAT has a relatively high activity and good thermostability. The pH and temperature optima of CtNMNAT were pH 6.0 and 60 degrees C. CtNMNAT was stable at 50 degrees C with a half-life of 25.9 h. The specificity constant k(cat)/K-M of CtNMNAT toward NMN was 180 s(-1) mM(-1) 28.5 mM NAD(+) was produced when using CtNMNAT as catalyst with a space-time yield of 72.0 g L-1 d(-1). This work provides a starting point for further investigation into the role of CtNMNAT in the NAD (+) metabolism of Chaetomium thermophilum and useful guidance for industrial application of CtNMNAT in the biocatalytic synthesis of NAD(+).