The narK gene product participates in nitrate transport induced in Escherichia coli nitrate-respiring cells.
The nucleotide sequence of the Escherichia coli narK gene, which is located in the upstream region of the narCHJI operon, was determined. The narK gene encodes a very hydrophobic protein with 463 amino acid residues (Mr 49,693). A narK deletion mutant, under conditions for the induction of nitrate respiration, was unable to perform nitrate transport. Loss of transport activity was recovered by transforming the mutant with a narK+ plasmid. Thus, we conclude that the narK gene encodes a transmembrane protein participating in nitrate transport. In the narK promoter region, we defined a unique sequence that we designate as a 'nitrate box', functioning as a putative NarL-binding site, in addition to the consensus sequence of the 'anaero-box'.
Noji
S
S
Department of Biochemistry, Okayama University Dental School, Japan.
Nohno
T
T
Saito
T
T
Taniguchi
S
S
D000595:Amino Acid Sequence; D001483:Base Sequence; D001693:Biological Transport, Active; D004269:DNA, Bacterial / Q000032:analysis; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009566:Nitrates / Q000378:metabolism*; D012045:Regulatory Sequences, Nucleic Acid
D004269:DNA, Bacterial; D009566:Nitrates