Open AccessMolecular cloning and DNA sequence of dni R, a gene affecting anaerobic expression of the Escherichia coli hexaheme nitrite reductase *
Author(s) -
Kajie Shinichi,
Ideta Ritsuro,
Yamato Ichiro,
Anraku Yasuhiro
Publication year - 1991
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1991.tb04441.x-i1
Subject(s) - nitrite reductase , microbiology and biotechnology , biology , reductase , pbr322 , gene , mutant , nucleic acid sequence , molecular cloning , escherichia coli , biochemistry , open reading frame , structural gene , 7 dehydrocholesterol reductase , complementary dna , enzyme , peptide sequence , nitrate reductase
A gene responsible for increased synthesis of hexaheme nitrite reductase (cytochrome c 552 ) of Escherichia coli K‐12 was cloned into pBR322 by the direct immunological screening method using antiserum against the purified enzyme. The cloned gene was mapped at 5 min on the chromosomal linkage map as the dni gene (related to increased synthesis of the dissimilatory nitrite reductase) by conjugation and transduction. The dni gene was subcloned into pUC118 and was shown to be on a 2.6‐kilobase‐pair Pst I‐ Bam HI fragment by immunoblottig analysis of the expressed enzyme. The nucleotide sequence of this fragment was determined. A plausible open‐reading frame corresponding to 222 amino acids was detected. Analysis of a dni deletion mutant by immunoblotting demonstrated that this mutant expressed a greatly reduced amount of the nitrite reductase. Thus, the dni gene is suggested to have a positive regulatory action on induced synthesis of the nitrite reductase, and was designated as dniR .