眼镜蛇毒L-氨基酸氧化酶的纯化、性质鉴定及细胞毒性测定

目的从眼镜蛇蛇毒中分离L-氨基酸氧化酶（LAAO）,测定其理化性质及细胞毒性。方法采用Superdex75凝胶层析、Phenyl-SepharoseFF疏水层析、ResourceS离子交换层析分离纯化LAAO;SDS-聚丙烯酰胺凝胶电泳及C18反相色谱鉴定纯度并测定相对分子量;CCK8法测定细胞毒性。结果舟山眼镜蛇蛇毒经凝胶层析、疏水层析、离子交换层析及C18反相色谱后获得LAAO（暂定名NA-LAAO）,在非还原和还原条件下相对分子质量均为58kD左右;具有明显的抑制人胃癌MGC-803细胞增殖作用。结论从眼镜蛇毒中纯化得到LAAO,其具有明显的细胞毒性。

Purification and characterization of L-amino acid oxidase from cobra venom

OBJECTIVE To purify a L-amino acid oxidase（LAAO）from the cobra venom and assay the cytotoxicity of LAAO.METHODS The L-amino acid oxidase was purified from the cobra venom by Superdex 75 gel filtration and Phenyl-Sepharose FF hydrophobic chromatography and Resource Sion-exchange chromatography.The purity and molecular weight of LAAO were appraised by SDS-polyacrylamide gel electrophoresis（Tris-Tricine system） and RP-HPLC.The cytotoxicity of LAAO was assayed by CCK8 method.RESULTS A novel L-amino acid oxidase from cobra venom,named NA-LAAO,was purified to homogeneity by the chromatography.The molecular weight of NA-LAAO was 58 kD.Furthermore,NA-LAAO showed significant cytotoxicity in the human gastric MGC-803 cells.CONCLUSION The NA-LAAO can be isolated and purified from cobra venom and showed the cytotoxicity.