灵芝中一种新的脱氧核糖核酸酶的纯化及特征  

Purification and characterization of a novel deoxyriboendonuclease from Ganoderma lucidum

作　　者：谢东扬[1,2] 祝雯[1,2] 吴祖建[1,2] 林奇英[1,2] 谢联辉[1,2] 

机构地区：[1]福建农林大学植物病毒研究所 [2]福建农林大学农药生物化学教育部重点实验室,福建福州350002

出　　处：《福建农林大学学报（自然科学版）》2007年第5期486-490,共5页Journal of Fujian Agriculture and Forestry University:Natural Science Edition

基　　金：福建省教育厅资助项目(2006F5014)

摘　　要：通过(NH4)2SO4沉淀,利用Blue Sepharose 6 Fast Flow和SP Sepharose Fast Flow层析方法从灵芝中分离纯化了一种脱氧核糖核酸酶,命名为GLDNase.通过质谱分析确定GLDNase精确分子质量为13807 u.SDS-PAGE电泳表明GLDNase为单亚基多肽,其N-端氨基酸序列为PLDTGRYHIYTW/T/CDGG.GLDNase可作用于ssDNA和dsDNA,是一种非限制性内切酶,酶活性依赖于二价金属阳离子Mg2+,10 mmol.L-1EDTA可完全抑制其活性.最适pH值为8.4,40℃时相对活性最高.GLDNase水解DNA的产物末端的基团为3′-OH、5′-磷酸.A novel deoxyribonuclease from the fruiting bodies of Ganoderma lucidum has been purified and designated as GLDNase. It was purified by ammonium sulphate precipitation, Blue Sepharose 6 Fast Flow and SP Sepharose Fast Flow. GLDNase showed a single protein band on SDS-PAGE. It showed a major mass peak of 13807 u analyzed in an electrospray-mass analyzer. Amino acid analysis of the N-terminus indicated that the sequence was PLDTGRYHIYTW/T/CDGG. GLDNase acted on both ssDNA and dsDNA. Its optimum pH and temperature were 8.4 and 40 ℃ respectively. It was a kind of non-restriction-endonuclease. Mg^2＋ was required for the endonuclase activity as a co-factor. The activity of the purified enzyme was completely inhibited by 10 mmol · L^-1 EDTA. The oligonucleotides produced by GLDNase had a phosphate group at the 5＇-termini and a hydroxyl group at the 3＇-termini.

关 键 词：灵芝 脱氧核糖核酸酶 纯化 

分 类 号：Q291[生物学—细胞生物学]