Purification and characterization of a kringle-deficit mutant of human plasminogen with Arg-Gly-Asp tripeptide expressed in Pichia pastorsis.
- Author:
Wu CHEN
1
;
Maocai WU
;
Jingyuan WU
;
Jianzhong YANG
;
Zhenlin CHEN
;
Zhihui HUANG
;
Xinyong ZHANG
;
Yun XIAO
Author Information
1. Life Science and Bio-pharmaceutics College, Guangdong Pharmaceutical University, Guangzhou 510006, China.
- Publication Type:Journal Article
- MeSH:
Humans;
Kringles;
genetics;
Oligopeptides;
biosynthesis;
genetics;
Pichia;
genetics;
metabolism;
Plasminogen;
biosynthesis;
genetics;
Platelet Aggregation Inhibitors;
isolation & purification;
pharmacology;
Point Mutation;
Recombinant Proteins;
biosynthesis;
genetics;
isolation & purification;
pharmacology
- From:
Chinese Journal of Biotechnology
2011;27(5):764-772
- CountryChina
- Language:Chinese
-
Abstract:
To obtain a recombinant human plasminogen (hPLG) with potential anti-platelet aggregation activity, we cloned the cDNA coding Pro544 to Asn791 of hPLG, a kringle-deficit derivative (hPLG-deltaK). The Pro559 in activation loop was then mutated into Asp559 to provide Arg-Gly-Asp (RGD) motif. The constructed pPICZalphaA-RGD-HPLG-deltaK plasmid was expressed in yeast Pichia pastoris GS115, which produced RGD-hPLG-deltaK about 0.160 g/L broth. After affinity chromatography, the purity of the recombinant protein reached above 90%. Western blotting test confirmed that it retained the immunological reaction capability as human PLG. Its urokinase activation rate in 24 hours and its fibrinolytic activity made no deference against native hPLG-deltaK (P=0.630, n=5). Importantly, after activation by urokinase, RGD-hPLG-deltaK showed a significantly higher platelet aggregation inhibition rate (Ri) (21.8% +/- 1.57%) than hPLG-deltaK (3.8% +/- 0.33%) (P=0.000, n=5). These results proved that we constructed an hPLG mutant with anti-platelet aggregation activity, which made a foundation for developing innovative thrombolytic drugs with multifunction.
