Zhang X, Zhu L, Deutscher M P
Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, Miami, Florida 33101-6129, USA.
J Bacteriol. 1998 May;180(10):2779-81. doi: 10.1128/JB.180.10.2779-2781.1998.
Oligoribonuclease, a 3'-to-5' exoribonuclease specific for small oligoribonucleotides, was purified to homogeneity from extracts of Escherichia coli. The purified protein is an alpha2 dimer of 40 kDa. NH2-terminal sequence analysis of the protein identified the gene encoding oligoribonuclease as yjeR (o204a), a previously reported open reading frame located at 94 min on the E. coli chromosome. However, as a consequence of the sequence information, the translation start site of this open reading frame has been revised. Cloning of yjeR led to overexpression of oligoribonuclease activity, and interruption of the cloned gene with a kanamycin resistance cassette eliminated the overexpression. On the basis of these data, we propose that yjeR be renamed orn. Orthologs of oligoribonuclease are present in a wide range of organisms, extending up to humans.
寡核糖核酸酶是一种对小寡核糖核苷酸具有特异性的3'至5'外切核糖核酸酶，它从大肠杆菌提取物中纯化至同质。纯化后的蛋白质是一种40 kDa的α2二聚体。对该蛋白质进行的氨基末端序列分析确定了编码寡核糖核酸酶的基因是yjeR（o204a），这是一个先前报道的位于大肠杆菌染色体94分钟处的开放阅读框。然而，根据序列信息，该开放阅读框的翻译起始位点已被修正。yjeR的克隆导致寡核糖核酸酶活性的过表达，用卡那霉素抗性盒中断克隆基因消除了过表达。基于这些数据，我们提议将yjeR重新命名为orn。寡核糖核酸酶同源物存在于广泛的生物体中，一直延伸到人类。
