Interaction of Bacillus subtilis purine repressor with DNA.
AUTOR(ES)
Shin, B S
RESUMO
A purine repressor (PurR) mediates adenine nucleotide-dependent regulation of transcription initiation of the Bacillus subtilis pur operon. This repressor has been purified for the first time, and binding to control site DNA was characterized. PurR binds in vitro to four operons. Apparent Kd values for binding were 7 nM for the pur operon, 8 nM for purA, 13 nM for purR, and 44 nM for the pyr operon. In each case, DNase I footprints exhibited a pattern of protected and hypersensitive sites that extended over more than 60 bp. A GAAC-N24-GTTC sequence in the pur operon was necessary but not sufficient for the PurR-DNA interaction. However, this motif, which is conserved in the four binding sites, was not required for binding of PurR to purA. Thus, the common DNA recognition element for binding of PurR to the four operons is not known. Multiple PurR-pur operon DNA complexes having a binding stoichiometry that was either approximately two or six repressor molecules per DNA fragment were detected. The results of a torsional constraint experiment suggest that control site DNA forms one right-handed turn around PurR.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=179690Documentos Relacionados
- Interaction of the Bacillus subtilis phage phi 105 repressor DNA: a genetic analysis.
- The Purine Repressor of Bacillus subtilis: a Novel Combination of Domains Adapted for Transcription Regulation
- Interaction of the Bacillus subtilis glnRA repressor with operator and promoter sequences in vivo.
- In Vivo Effect of Mutations at the PRPP Binding Site of the Bacillus subtilis Purine Repressor
- Transformation of Bacillus subtilis by single-stranded plasmid DNA.
