The Expression of Human Carboxypeptidase Al and Its Active Center Gene / 中国肿瘤生物治疗杂志

ABSTRACT

Objective: To clone human carboxypeptidase A1 and its active center gene as well as construct recombinant vector for expression before analysis their activities. Methods: CPA1 and CPAlactive center gene were amplified by RT-PCR from pancreas tissue, and then sequencing was carried out. The correct target genes were cloned into prokaryotic vector pGEX-4T-1 and transformed into E. coli BL21 before sequence analysis. After induced by IPTG, gene products were analyzed by SDS-PAGE. Target expressed proteins were denaturated, renaturated, purified and evaluated through MTT and agar colony form test. Results: Human carboxypeptidase Al and its active center gene were cloned successfully. New expected protein band of Mr 66,000 and 46,000 appeared on SDS-PAGE after inducement. Both of the expressed proteins have catalytic activity in vitro, but the activity of the latter is inferior when applied to tumor cells. Conclusions: Human carboxypeptidase A1 and its active center gene were cloned successfully. Their prokaryotic expression products were obtained too. The expressed proteins have catalytic activity in. vitro. A new prosperous beginning of further improvement for CPA1 therapy system has been established based on CPA1 and its active center gene in terms of ADEPT against prostate cancer to clinical application.