title: Acceptor substrate binding revealed by crystal structure of human glucosamine-6-phosphate N-acetyltransferase 1.
abstract: Glucosamine-6-phosphate (GlcN6P) N-acetyltransferase 1 (GNA1) is a key enzyme in the pathway toward biosynthesis of UDP-N-acetylglucosamine, an important donor substrate for N-linked glycosylation. GNA1 catalyzes the formation of N-acetylglucosamine-6-phosphate (GlcNAc6P) from acetyl-CoA (AcCoA) and the acceptor substrate GlcN6P. Here, we report crystal structures of human GNA1, including apo GNA1, the GNA1-GlcN6P complex and an E156A mutant. Our work showed that GlcN6P binds to GNA1 without the help of AcCoA binding. Structural analyses and mutagenesis studies have shed lights on the charge distribution in the GlcN6P binding pocket, and an important role for Glu156 in the substrate binding. Hence, these findings have broadened our knowledge of structural features required for the substrate affinity of GNA1.
authors.affiliation: National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Wang
authors.forename: Xiang
authors.initials: X
authors.lastname: Liu
authors.forename: Yu-He
authors.initials: YH
authors.lastname: Liang
authors.forename: Lan-Fen
authors.initials: LF
authors.lastname: Li
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Su
mesh_terms: D000105:Acetyl Coenzyme A / Q000737:chemistry; D000409:Alanine / Q000737:chemistry / Q000235:genetics; D001051:Apoenzymes / Q000737:chemistry; D018360:Crystallography, X-Ray; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000737:chemistry; D051081:Glucosamine 6-Phosphate N-Acetyltransferase / Q000737:chemistry* / Q000235:genetics; D019298:Glucose-6-Phosphate / Q000031:analogs & derivatives* / Q000737:chemistry; D018698:Glutamic Acid / Q000737:chemistry / Q000235:genetics; D006801:Humans; D016296:Mutagenesis
chemical_list: D001051:Apoenzymes; C001293:glucosamine 6-phosphate; D018698:Glutamic Acid; D019298:Glucose-6-Phosphate; D000105:Acetyl Coenzyme A; C494970:GNPNAT1 protein, human; D051081:Glucosamine 6-Phosphate N-Acetyltransferase; D005944:Glucosamine; D000409:Alanine