title: Chitinase-catalyzed synthesis of an alternatingly N-sulfonated chitin derivative.
abstract: An alternatingly N-sulfonated chitin derivative (2) was synthesized via ring-opening polyaddition of an N-sulfonated chitobiose oxazoline derivative (1) catalyzed by chitinases from Bacillus sp. and Serratia marcescens. The polymerization proceeded homogeneously, providing 2 as a water-soluble polysaccharide in good yields with total control of regioselectivity and stereochemistry. M(n) of 2 reached 1900 and 4180 by use of chitinases from Bacillus sp. and Serratia marcescens, which correspond to 8-10 (n = 4-5) and 18-20 (n = 9-10) saccharide units, respectively. These results indicate that M(n) of 2 is controllable by selecting chitinases from different origins. It is considered that the C-2 position of the nonreducing unit in the oxazoline-type monomer is not deeply involved in the catalysis of chitinase.
authors.affiliation: Department of Materials Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Makino
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nagashima
authors.forename: Masashi
authors.initials: M
authors.lastname: Ohmae
authors.forename: Shiro
authors.initials: S
authors.lastname: Kobayashi
mesh_terms: D001407:Bacillus / Q000378:metabolism; D001669:Biochemical Phenomena; D001671:Biochemistry; D002236:Carbohydrate Conformation; D002384:Catalysis; D002686:Chitin / Q000737:chemistry*; D002688:Chitinases / Q000737:chemistry*; D046911:Macromolecular Substances; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008968:Molecular Conformation; D008970:Molecular Weight; D012706:Serratia marcescens / Q000378:metabolism; D013455:Sulfur / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D002686:Chitin; D013455:Sulfur; D002688:Chitinases