【作者】 马端征； 王贺祥；

【Author】 MA Duan-Zheng WANG He-Xiang~* College of Biological Sciences,China Agricultural University,Beijing 100193,China

【机构】 中国农业大学生物学院；

【摘要】 本研究通过DEAE-cellulose、S-sepharose等离子交换层析、凝胶过滤等方法,以短柄黏盖牛肝菌Suillus brevipes的干子实体为材料,分离纯化出一个新的核糖核酸酶（RNase）。短柄黏盖牛肝菌核糖核酸酶是一个分子量为32kDa的单亚基蛋白,其N-端氨基酸序列为GGSGHGTSGPASHQN,与已报道的大型真菌核糖核酸酶氨基酸序列无显著同源性。该RNase最适反应温度50℃,最适反应pH为5左右。大部分金属离子对短柄黏盖牛肝菌RNase的活性有抑制作用,以Cu²⁺、Al³⁺、Hg²⁺对其的抑制作用最为明显,该酶抑制HIV-1反转录酶的IC₅₀为7.1μmol/L,体外抑制人肝癌细胞株Hep G2和人乳腺癌细胞株MCF-7细胞系增殖的IC₅₀分别为19.7μmol/L和13.0μmol/L。更多还原

【Abstract】 A novel ribonucleases（RNase） was purified from dry fruiting bodies of Suillus brevipes using a purification procedure which involved ion exchange chromatography on DEAE-cellulose and S-sepharose,and gel filtration by FPLC on Superdex 75 column.The Suillus brevipes ribonuclease was a monomeric protein with a molecular weight of 32kDa,and the N-terminal sequence of the RNase was GGSGHGTSGPASHQN,unique in the reported large fungi RNases.The temperature optimum for this RNase is 50℃,and the pH optimum for it is about pH 5.The activity of the RNase was inhibited by a majority of metal ions tested,especially Cu²⁺,Al³⁺,and Hg²⁺.The RNase exhibited strong inhibitory activity against HIV-1 reverse transcriptase（HTV-1 RT） with an IC₅₀ of 7.1μmol/L.The RNase also observably inhibited the proliferation of tumor cells Hep G2 and MCF-7 with IC₅₀ of 19.7μmol/L and 13.0μmol/L,respectively in vitro.更多还原