Sodergren E J, DeMoss J A
Department of Biochemistry and Molecular Biology, University of Texas Medical School, Houston 77025.
J Bacteriol. 1988 Apr;170(4):1721-9. doi: 10.1128/jb.170.4.1721-1729.1988.
In previous studies it has been established that in Escherichia coli the three known subunits of anaerobic nitrate reductase are encoded by the narGHI operon. From the nucleotide sequence of the narI region of the operon we conclude that, in addition to the narG and narH genes, the nar operon contains two other open reading frames (ORFs), ORF1 and ORF2, that encode proteins of 26.5 and 25.5 kilodaltons, respectively. Protein fusions to each of the genes in the operon showed that expression of all four genes was similarly regulated. The reading frames of ORF1 and ORF2 were verified, and the N-terminal sequence for the ORF1 fusion protein was determined. The nar operon therefore contains four genes designated and ordered as narGHJI.
在先前的研究中已经确定，在大肠杆菌中，厌氧硝酸还原酶的三个已知亚基由narGHI操纵子编码。根据该操纵子narI区域的核苷酸序列，我们得出结论，除narG和narH基因外，nar操纵子还包含另外两个开放阅读框（ORF），即ORF1和ORF2，它们分别编码26.5千道尔顿和25.5千道尔顿的蛋白质。与操纵子中每个基因的蛋白质融合表明，所有四个基因的表达受到类似的调控。ORF1和ORF2的阅读框得到了验证，并确定了ORF1融合蛋白的N端序列。因此，nar操纵子包含四个基因，命名并排序为narGHJI。
