title: Chemical modification of L-asparaginase with a comb-shaped copolymer of polyethylene glycol derivative and maleic anhydride.
abstract: L-Asparaginase from Escherichia coli, an anti-tumor enzyme, was chemically modified with two types of maleic anhydride copolymers with a comb-shaped form, the one composed of polyoxyethylene allyl methyl diether with the molecular weight of 13,000 (activated PM13) and the other of polyoxyethylene 2-methyl-2-propenyl methyl diether with 100,000 (activated PM100). The modified asparaginases (PM13- and PM100-asparaginases) exhibited the complete loss of immunoreactivity towards anti-asparaginase serum. The enzymic activity of PM100-asparaginase without immunoreactivity was well retained by 85% of non-modified one, while that of PM13-asparaginase was retained 46%. These results were discussed in relation to the chemical structure of modifying reagents including chain shaped-polyethylene glycol derivatives.
authors.affiliation: Department of Materials Science and Technology, Toin University of Yokohama, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kodera
authors.forename: H
authors.initials: H
authors.lastname: Tanaka
authors.forename: A
authors.initials: A
authors.lastname: Matsushima
authors.forename: Y
authors.initials: Y
authors.lastname: Inada
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001215:Asparaginase / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D007700:Kinetics; D008299:Maleic Anhydrides / Q000378:metabolism*; D008968:Molecular Conformation; D011092:Polyethylene Glycols / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet; D014302:Trinitrobenzenesulfonic Acid
chemical_list: D000596:Amino Acids; D008299:Maleic Anhydrides; D011092:Polyethylene Glycols; D014302:Trinitrobenzenesulfonic Acid; D001215:Asparaginase