The mature Q49D-PLA2 mutant was obtained by Hitrap SP cation exchange and Superdex 75 gel filtration chromatography,with the recovery rate of 1.3%,and the specific activity of the mature Q49D-PLA2 mutant was 72 U/mg.

• 突变体融合蛋白经蛋白水解酶Factor Xa酶切后；采用Hitrap SP阳离子交换层析和Superdex75凝胶层析进一步纯化；得到突变体蛋白Q49D-PLA2；得率为1.；3%25；比酶活为72U/mg。