Open AccessnarI region of the Escherichia coli nitrate reductase (nar) operon contains two genes
Author(s) -
Erica Sodergren,
John A. DeMoss
Publication year - 1988
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.170.4.1721-1729.1988
Subject(s) - operon , biology , open reading frame , orfs , escherichia coli , nucleic acid sequence , gene , genetics , reading frame , nitrate reductase , gal operon , trp operon , peptide sequence , microbiology and biotechnology , biochemistry , enzyme
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.