Enhance production of recombinant lumbrokinase by optimizing gene codon usage for expression in Pichia pastoris and its properties

摘要

Lumbrokinase (LK), as a group of potential fibrinolytic enzymes from earthworm having molecular weights of 25 to 40 kDa that removal of these fibrinopeptides leads to production of soluble fibrin clot and prevents the ability of blood clots. In this study, the gene encoding for a LK from the earthworm Eisenia fetida (GenBank Accession No. AF304199) was optimized codon for expression in P. pastoris under the control of an AOX1 promoter. The recombinant lines were screened based on the ability to express LK. The molecular weight of recombinant LK was determined by SDS-PAGE, was 47 kDa, purified and renatured using nickel-chelating resin with a recovery rate of 12.96%. The concentration of recombinant lumbrokinase was 215 mg/l and fibrinolytic activity of rLK was 3.58 U/mg calculated by comparison with the activity of a plasmin standard. The main physiochemical features of the lumbrokinase including temperature stability and pH resistance. Metal ions, detergents, and organic solvents tested indicated a significantly influence on rLK activity. These results suggested that the lumbrokinase expressed in P. pastoris could potentially be used as additive for the treatment of diseases associated with thrombosis.