Chitinase hybrid polysaccharides

Characterization data of the resulting cellulose-chitin hybrid polysaccharide 3 are summarized in Table 1. The average molecular wei t value (M ) of the resulting product 3 via cellulase- and chitinase catalyzed polymerization reached to 2840 and 4030, which correspond to 15-16 and 22 saccharide units, respectively. 

The yields and Mn value of the resulting chitin-chitosan hybrid polysaccharides 8 under various reaction conditions were summarized in Table 2. The yields of 8 were around 60-75% and there were little significant differences in catalysis between these two enzymes except for the reaction time. However, A4 value of 8 reached 1600 and 2020 with using chitinases from Bacillus sp. and Serratia marcescens, respectively, which correspond to 8-10 (n = 4-5) and 10-12 (n = 5-6) saccharide units, respectively. These results Indicated that values of polysaccharides are controllable to some extent by selecting enzymes from different origins. 

Chitinase from Bacillus sp. was added to a solution of Xyl (l— 4)GlcNAc oxazoline 13 dissolved into a phosphate buffer. The consumption rate of 13 was accelerated by the enzyme addition and chitin-xylan hybrid polysaccharide 14 was produced. During the polymerization, the reaction proceeded homogenously throughout the reaction. The yield was 76% and its average molecular weight value of 14 was M = 1500 with MJMa = 1.76, determined by GPC. Furthermore, MALDI-TOF mass spectrum of 14 indicated the peaks at every m/z 335, which corresponds to the molecular mass of the repeating disaccharide unit. 

Makino, A., K. Kurosaki, M. Ohmae, and S. Kobayashi. 2006b. Chitinase-catalyzed synthesis of altematingly V-deacetylated chitin A chitin-chitosan hybrid polysaccharide. Biomacromolecules 7 950-957. 

Kobyashi S., Makino A., Tachibana N., Ohmae M., Chitinase-catalyzed synthesis of a chitin-xylan hybrid polymer A novel water-soluble P(1 <— 4) polysaccharide having an JV-acetylglucosamine-xylose repeating unit, Macromol. Rapid Comm., 27,2006, 781-786. 

A cellulose-chitin hybrid polymer, a nonnatural polysaccharide having a glucose unit and an N-acetyl glucosamine unit alternatingly in the main chain, was synthesized by chitinase-catalyzed polyaddition of a disaccharide oxazoline monomer in an aqueous solution (44). 

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