tailieunhanh - Linkage of nanosecond protein motion with enzymatic methyl transfer by nicotinamide N-methyltransferase

Nicotinamide N-methyltransferase (NNMT), a key cytoplasmic protein in the human body, is accountable to catalyze the nicotinamide (NCA) N1 -methylation through S-adenosyl-L-methionine (SAM) as a methyl donor, which has been linked to many diseases. Although extensive studies have concerned about the biological aspect, the detailed mechanism study of the enzyme function, especially in the part of protein dynamics is lacking. Here, wild-type nicotinamide N-methyltransferase together with the mutation at position 20 with Y20F, Y20G, and free tryptophan were carried out to explore the connection between protein dynamics and catalysis using time-resolved fluorescence lifetimes. The results show that wild-type nicotinamide N-methyltransferase prefers to adapt a less flexible protein conformation to achieve enzyme catalysis. | Turkish Journal of Biology Turk J Biol 2021 45 333-341 http biology TÜBİTAK Research Article doi biy-2101-54 Linkage of nanosecond protein motion with enzymatic methyl transfer by nicotinamide N-methyltransferase 1 1 1 1 2 1 1 Yahui JING Yiting CHENG Fangya LI Yuping LI Fan LIU Jianyu ZHANG 1 School of Pharmaceutical Science and Technology Tianjin University Tianjin China 2 Binzhou Institute for Food and Drug Control Binzhou Shandong China Received Accepted Published Online Final Version Abstract Nicotinamide N-methyltransferase NNMT a key cytoplasmic protein in the human body is accountable to catalyze the nicotinamide NCA N1-methylation through S-adenosyl-L-methionine SAM as a methyl donor which has been linked to many diseases. Although extensive studies have concerned about the biological aspect the detailed mechanism study of the enzyme function especially in the part of protein dynamics is lacking. Here wild-type nicotinamide N-methyltransferase together with the mutation at position 20 with Y20F Y20G and free tryptophan were carried out to explore the connection between protein dynamics and catalysis using time-resolved fluorescence lifetimes. The results show that wild-type nicotinamide N-methyltransferase prefers to adapt a less flexible protein conformation to achieve enzyme catalysis. Key words Protein dynamics nicotinamide N-methyltransferase methyl transfer time-resolved fluorescence 1. Introduction responsible approach for investigating small-scale protein The secret of how the enzyme can achieve such amazing dynamics in the nanosecond range. Here nicotinamide catalytic capabilities has not been fully revealed yet. N-methyltransferase and its mutants were selected and From protein movement Bruice 2002 Hammes et combed with enzyme activity and protein fluorescence al. 2011 Da et al. 2014 electrostatic preorganization measurements to explore the relationship between protein effect Warshel