文献类型：期刊文献

英文题名：Chemical modification of L-asparaginase from Escherichia coli with a modified polyethyleneglycol under substrate protection conditions

作者：Zhang, JF; Shi, LY; Wei, DZ

机构：[1]E China Univ Sci & Technol, Res Inst Biochem, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2004

卷号：26

期号：9

起止页码：753

外文期刊名：BIOTECHNOLOGY LETTERS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000220849300013)】；

语种：英文

外文关键词：L-asparaginase; chemical modification; polyethyleneglycol

摘要：L-Asparaginase was chemically modified with 2,4-bis(O-methoxypolyethyleneglycol)-6-chloro-S-triazine (mPEG(2)) in the presence of L-asparagine. Optimal modification was performed under the condition that the molar ratio of mPEG(2)/-NH2 is 10. The modified enzyme retained 33% of initial enzymatic activity with complete abolishment of immunogenicity. In vitro half-life increment from 4.6 h to 33 h has been obtained.