Xu Li-Jing, Chen Qing-Jun, Wang He-Xiang, Zhang Guo-Qing
State Key Laboratory for Agrobiotechnology,d Department of Microbiology, China Agricultural University, Beijing 100193, China.
Indian J Biochem Biophys. 2013 Jun;50(3):196-201.
A 15 kDa ribonuclease (RNase) was purified from dried fruiting bodies of the wild edible mushroom Armillaria luteo-virens. The simple 4-step purification protocol involved ion-exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on SP-Sepharose and a final gel filtration by FPLC on Superdex-75. The RNase was unadsorbed on Affi-gel blue gel, but adsorbed on DEAE-cellulose and SP-Sepharose. The N-terminal amino acid sequence of purified RNase was AGVQYKLTILLV, which showed low sequence homology to those of previously reported RNases. The optimal pH and temperature of the enzyme were very close to 4.0 and 70 degrees C, respectively. The enzyme showed considerably high ribonucleolytic activity and broad specificity towards polyhomoribonucleotides, with a specificity of poly(U) > poly(C) > poly (G) > poly(A). The ribonucleolytic activities towards poly(U), poly(C), poly(G) and poly(A) were 279.5, 184.1, 69.9 and 52.3 U/mg, respectively.
从野生可食用蘑菇黄绿蜜环菌的干燥子实体中纯化出一种15 kDa的核糖核酸酶（RNase）。简单的四步纯化方案包括在DEAE - 纤维素上进行离子交换色谱、在Affi - gel蓝胶上进行亲和色谱、在SP - Sepharose上进行离子交换色谱以及最后通过FPLC在Superdex - 75上进行凝胶过滤。该核糖核酸酶不吸附在Affi - gel蓝胶上，但吸附在DEAE - 纤维素和SP - Sepharose上。纯化后的核糖核酸酶的N端氨基酸序列为AGVQYKLTILLV，与先前报道的核糖核酸酶的序列同源性较低。该酶的最适pH和温度分别非常接近4.0和70℃。该酶对多聚同型核糖核苷酸表现出相当高的核糖核酸酶活性和广泛的特异性，特异性为多聚尿苷酸（poly(U)）＞多聚胞苷酸（poly(C)）＞多聚鸟苷酸（poly(G)）＞多聚腺苷酸（poly(A)）。对多聚尿苷酸、多聚胞苷酸、多聚鸟苷酸和多聚腺苷酸的核糖核酸酶活性分别为279.5、184.1、69.9和52.3 U/mg。
