Properties of a mutant form of the prokaryotic enhancer binding protein, NTRC, which hydrolyses ATP in the absence of effectors.
The mutation S170A in the proposed nucleotide binding site of the transcriptional activator protein NTRC abolishes its ability to catalyse open promoter complex formation by the sigma(N)-RNA polymerase holoenzyme. NTRC(S170A) has significant ATPase activity, which, in contrast to the wild-type protein, is unaffected by phosphorylation or binding to enhancer sites on DNA. The mutant protein appears to oligomerise normally on DNA in response to phosphorylation but the ATPase activity is apparently not responsive to changes in oligomerisation state. The defect in transcriptional activation is discussed in relation to mutations in other sigma(N)-dependent activators.
Widdick
D
D
Nitrogen Fixation Laboratory, John Innes Centre, Norwich, UK.
Farez-Vidal
E
E
Austin
S
S
Dixon
R
R
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism*; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D005974:Glutamate-Ammonia Ligase / Q000235:genetics; D006868:Hydrolysis; D009154:Mutation; D051922:PII Nitrogen Regulatory Proteins; D010766:Phosphorylation; D011485:Protein Binding; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D051922:PII Nitrogen Regulatory Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; C081173:glutamine synthetase I; D005974:Glutamate-Ammonia Ligase