Synthesis of Hydrophobic Poly(γ-Glutamic Acid) Derivatives by Enzymatic Grafting of Partially 2-Deoxygenated Amyloses

We have previously found that a partially 2-deoxygenated (P2D)-amylose, produced by glucan phosphorylase (GP)-catalyzed enzymatic copolymerization, shows hydrophobic nature. Based on this finding, the present study demonstrates hydrophobization of strong hydrophilic polypeptide, i.e., poly(γ-glutamic acid) (PGA), grafting P2D-amylose chains via GP-catalyzed approach. After maltooligosaccharide primers for reaction were modified PGA chain, we performed copolymerization d-glucan with α-d-glucose 1-phosphate as comonomers in different feed ratios from to produce P2D-amylose-grafted PGAs. analyzed structures (chemical and crystalline) products, precipitated mixtures, 1H NMR powder X-ray diffraction measurements, respectively. The values water contact angle cast films, prepared DMSO solutions products 2-deoxyglucose/glucose unit ratios, greater than 100°, indicating efficient polypeptide