Sano M, Nakamura A, Masaki H, Uozumi T
Department of Biotechnology, Faculty of Agriculture, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan.
Curr Genet. 1996 Sep;30(4):312-7. doi: 10.1007/s002940050138.
Nuclease O in the mycelia of Aspergillus oryzae has been purified 55-fold by successive steps of chromatography from the filtrate of the autolyzate. The molecular mass of nuclease O was 32 kDa, as estimated by SDS polyacrylamide-gel electrophoresis. The nuclease O gene (nucO) encoding this enzyme was cloned and sequenced. The open reading frame is interrupted by four introns with conserved splice sites and contains 328 amino-acid residues of the mature enzyme. A. nidulans transformants obtained by introduction of the cloned nucO gene produced 2.5-times as much nuclease O as the wild-type strain, showing that the cloned DNA fragment encodes nuclease O.
通过对米曲霉自溶产物滤液进行连续色谱步骤，米曲霉菌丝体中的核酸酶O已被纯化55倍。经SDS聚丙烯酰胺凝胶电泳估计，核酸酶O的分子量为32 kDa。编码该酶的核酸酶O基因（nucO）被克隆并测序。开放阅读框被四个具有保守剪接位点的内含子打断，包含成熟酶的328个氨基酸残基。通过导入克隆的nucO基因获得的构巢曲霉转化体产生的核酸酶O是野生型菌株的2.5倍，表明克隆的DNA片段编码核酸酶O。
