title: Synthesis of α(1→4)-linked non-natural mannoglucans by α-glucan phosphorylase-catalyzed enzymatic copolymerization.
abstract: α-Glucan phosphorylase catalyzes enzymatic polymerization of α-d-glucose 1-phosphate (Glc-1-P) as a monomer from a maltooligosaccharide primer to produce α(1→4)-glucan, i.e., amylose, with liberating inorganic phosphate (Pi). Because of quite weak specificity for the recognition of substrates by thermostable α-glucan phosphorylase (from Aquifex aeolicus VF5), in this study, we investigated the enzymatic copolymerization of Glc-1-P with its analogue monomer, α-d-mannose 1-phosphate (Man-1-P) under the conditions for removal of Pi as the precipitate with ammonium and magnesium in ammonia buffer containing Mg(2+) ion to produce α(1→4)-linked non-natural mannoglucans composed of Glc/Man units. The reaction was conducted in different feed ratios using the maltotriose primer at 40°C for 7days. The MALDI-TOF mass and (1)H NMR spectra of the products fully supported the mannoglucan structures.
authors.affiliation: Graduate School of Science and Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Baba
authors.affiliation: Graduate School of Science and Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Graduate School of Science and Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890-0065, Japan. Electronic address: kadokawa@eng.kagoshima-u.ac.jp.
authors.forename: Jun-Ichi
authors.initials: JI
authors.lastname: Kadokawa
mesh_terms: D055162:Biocatalysis; D060326:Chemistry Techniques, Synthetic; D006005:Phosphorylases / Q000378:metabolism*; D058105:Polymerization; D011134:Polysaccharides / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D011134:Polysaccharides; C493955:mannoglucan; D006005:Phosphorylases
keywords: Enzymatic copolymerization; Mannoglucan; Non-natural polysaccharide; α-Glucan phosphorylase