广西眼镜王蛇毒一种碱性蛋白的分离纯化及性质研究  

PURIFICATION AND CHARACTERIZATION OF A BASIC PROTEIN FROM GUANGXI KING COBRA (OPHIOPHAGUS HANNAH) VENOM

作　　者：林文珍[1] 庄茂辛[1] 舒雨雁[2] 林政炯[3] 周元聪[4] 

机构地区：[1]广西医科大学生物化学与分子生物学教研室,南宁530021 [2]广西医科大学蛇毒研究所,南宁530021 [3]中国科学院生物物理研究所生物大分子国家重点实验室,北京100101 [4]中国科学院上海生命科学院生物化学与细胞生物学研究所,上海200031

出　　处：《广西医科大学学报》2007年第2期189-192,共4页Journal of Guangxi Medical University

基　　金：国家自然基金资金资助(No.39970174)

摘　　要：目的:广西眼镜王蛇毒一种碱性蛋白的分离纯化和性质研究。方法:分离纯化采用DEAE-Sepharose CL-6B离子交换柱层析,Sephadex G-75凝胶过滤和CM-Sepharose CL-6B离子交换柱层析;通过电泳,磷脂酶A2(PLA2)酶活力测定,氨基酸组成分析,N端序列测定及药理实验进行性质研究。结果:从广西眼镜王蛇毒中分离到一种电泳纯的碱性蛋白(命名为CM-IV),相对分子质量约为14000,等电点约为8.65;PLA2的比活力为23μmol·mg-1/min。氨基酸组成分析表明,其分子中Cys的含量占6.85%;利用蛋白质直接测序N端序列为TKCYVTPDVK。药理实验表明它对实验用小白鼠有致死性(LD50约为0.2mg/kg),并具有心脏毒性,但无血小板抑制活性。根据Genebank Blast分析软件,它的N端序列与神经毒素具有高度的同源性。结论:这种碱性蛋白可能为神经毒素,但却拥有PLA2的活力。Objective： To purify and characterize a basic protein from Guangxi King cobra（Ophiophagus hannah） venom. Methods. Isolation and purification of a basic protein was done by successive chromatography on DEAE-Sepharose CL-6B, Sephadex G-75 and CM-Sepharose CL-6B column. The characterizations of this protein were studied by electrophoresis, phospholipase A2 activity analysis, amino acid analysis, N-terminal sequence analysis and pharmacology experiments. Result： A basic protein named CM-IV was isolated from Guangxi king cobra venom. Its relative molecular weight was 14 000, pI was 8.65, phospholipase A2 activity was 23μmol·mg^-1/min. Analysis of the amino acid showed that the percentage of Cys was 6.85%. N-terminal sequence was TKCYVTPDVK. This basic pr.otein has lethal activity（LD50≈0.2 mg/kg） for mouse. It exhibits cardiotoxic activities, but not anticoagulant activities. According Genebank Blast, we found that N-terminal sequence of this basic protein shares high amino acid homology with long neurotoxin. Conclusion： These results indicate that this protein maybe neurotoxin, but has weak phospholipase A2 activity.

关 键 词：眼镜王蛇 纯化 性质 碱性蛋白 

分 类 号：R996.3[医药卫生—毒理学]