Improvement of Characteristic of L-Asparaginase through Fusing Six Self-Assembling Amphipathic Peptides to Its N-Terminal

Abstract:

L-asparaginase（Asn） can catalyzes the hydrolysis of L-asparagine to L-aspartic acid and ammonia. It is mainly applied in pharmaceutical and food industry. In this study，to improve the characteristic of Asn，we fused six self-assembling amphipathic peptides（SAPs） to its N-terminal and expressed the recombinant Asns in E. coli，respectively. Compared to wide-type Asn，the SAP4-Asn activity increased by 30%，the value of Km decreased by 7.5% and the Vmax increased by 10%. The reaction kinetics analysis showed that the affinity ability and catalytic efficiency of the fusion enzyme towards L-asparagine improved compared to wide-type Asn.