The Hemolytic Site of the Basic Phospholipase A₂ from Agkistrodon halys Pallas

JIAO Hao-Mang,JIN Qian,ZHAO Jing-Jing,FENG Bo,
WU Xiang-Fu,ZHOU Yuan-Cong^*
( Institute of Biochemistry and Cell Biology,the Chinese Academy of Sciences,Shanghai 200031,China )

Abstract    The gene of the basic phospholipase A₂ from Agkistrodon halys Pallas (BPLA₂ )was mutated site-directedly by polymerase chain reaction (PCR) and the residue Arg³⁴ of the encloding protein was substituted by Glu and Gln，respectively.The mutant gene has been cloned into the expression vector pBLMVL2 and has been expressed in E.coli RR1 effectively.The protein was produced as insoluble inclusion bodies.After partial purification, the inclusion bodies were denatured and renatured into active form,and the renatured recombinant protein was purified by gel-filtration.The expression product has the same enzymatic activity as the denatured-refolded BPLA₂ and its hemolytic activity dropped distinctly,which suggest that the basic residue Arg³⁴ of BPLA₂ is a crucial amino acid residue during the process of hemolysis.
Key words Agkistrodon halys Pallas；basic phospholipase A₂；hemolysis

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