Cloning, sequencing, and transcriptional studies of the gene encoding copper-containing nitrite reductase from Alcaligenes xylosoxidans NCIMB 11015.
Gene encoding of the blue copper-containing nitrite reductase (nir) from Alcaligenes xylosoxidans NCIMB 11015 has been cloned and characterized. The nir is translated into a polypeptide of 360 amino acid residues as a precursor, and the N-terminal 24 residues are subsequently removed upon transport into the periplasm as a mature protein. A specific transcription product of nir was detected only in the presence of nitrate. The aeration level of the culture medium did not show a significant effect on the transcriptional level. A varsigma54 binding sequence is identified upstream of the transcriptional initiation at 53 to 26 nucleotides. A putative fnr box has also been identified in the sequence of the upstream region. The mature polypeptide showed 70% sequence identity with those of the Achromobacter cycloclastes enzyme. The transcriptional start point has been determined at 92 nucleotides upstream of the initiation codon and is preceded by the binding sites for varsigma54 and the fnr box. These results suggest that gene expression depends on the presence of nitrate and is stimulated under an anaerobic environment.
Faculty of Science, Ibaraki University, Japan.
E
E
Suzuki
N
N
Horikoshi
T
T
Kohzuma
D020121:5' Untranslated Regions / Q000235:genetics; D000421:Alcaligenes / Q000201:enzymology* / Q000235:genetics; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D003300:Copper / Q000737:chemistry*; D005798:Genes, Bacterial; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009572:Nitrite Reductases / Q000235:genetics*; D010442:Peptide Chain Initiation, Translational / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014158:Transcription, Genetic
D020121:5' Untranslated Regions; D003300:Copper; D009572:Nitrite Reductases; C052695:nitrite reductase, copper-containing