title: Enzymatic α-glucuronylation of maltooligosaccharides using α-glucuronic acid 1-phosphate as glycosyl donor catalyzed by a thermostable phosphorylase from Aquifex aeolicus VF5.
abstract: This paper describes thermostable phosphorylase-catalyzed α-glucuronylation of maltooligosaccharides for the direct synthesis of anionic oligosaccharides having a glucuronic acid residue at the non-reducing end. When the reaction of α-glucuronic acid 1-phosphate (GlcA-1-P) as a glycosyl donor and maltotriose as a glycosyl acceptor was performed in the presence of thermostable phosphorylase from Aquifex aeolicus VF5, high performance anion exchange chromatography analysis of the reaction mixture suggested the production of a glucuronylated tetrasaccharide, whose structure was also confirmed by the MALDI-TOF MS measurement of the crude products. Furthermore, treatment of the crude products with glucoamylase supported that the α-glucuronic acid unit was positioned at the non-reducing end of the tetrasaccharide and (1)H NMR analysis suggested that it was bound in an α-(1→4)-linkage. When the α-glucuronylation of maltotetraose using GlcA-1-P was conducted, α-glucuronylated oligosaccharides with various degrees of polymerization were produced. On the other hand, the α-glucuronylation of maltotetraose using GlcA-1-P in the presence of potato phosphorylase did not occur at all, indicating no recognition of GlcA-1-P by potato phosphorylase.
authors.affiliation: Graduate School of Science and Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Umegatani
authors.forename: Hironori
authors.initials: H
authors.lastname: Izawa
authors.forename: Mutsuki
authors.initials: M
authors.lastname: Nawaji
authors.forename: Kazuya
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Akiko
authors.initials: A
authors.lastname: Kubo
authors.forename: Michiyo
authors.initials: M
authors.lastname: Yanase
authors.forename: Takeshi
authors.initials: T
authors.lastname: Takaha
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Kadokawa
mesh_terms: D001419:Bacteria / Q000201:enzymology*; D055162:Biocatalysis; D004795:Enzyme Stability; D005965:Glucuronates / Q000737:chemistry*; D006031:Glycosylation; D009844:Oligosaccharides / Q000737:chemistry*; D006005:Phosphorylases / Q000378:metabolism*; D013403:Sugar Phosphates / Q000737:chemistry*; D013696:Temperature
chemical_list: D005965:Glucuronates; D009844:Oligosaccharides; D013403:Sugar Phosphates; C021705:maltooligosaccharides; D006005:Phosphorylases