The catabolite activator protein stabilizes its binding site in the E. coli lactose promoter.
AUTOR(ES)
DeGrazia, H
RESUMO
The effect of catabolite activator protein, CAP, on the thermal stability of DNA was examined. Site specific binding was studied with a 62 bp DNA restriction fragment containing the primary CAP site of the E. coli lactose (lac) promoter. A 144 bp DNA containing the lac promoter region and a 234 bp DNA from the pBR322 plasmid provided other DNA sites. Thermal denaturation of protein-DNA complexes was carried out in a low ionic strength solvent with 40% dimethyl sulfoxide, DMSO. In this solvent free DNA denatured below the denaturation temperature of CAP. The temperature stability of CAP for site specific binding was monitored using an acrylamide gel electrophoresis assay. Results show that both specific and non-specific CAP binding stabilize duplex DNA. Site specific binding to the 62 bp DNA produced a 13.3 degrees C increase in the transition under conditions where non-specific binding stabilized this DNA by 2-3 degrees C.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=322057Documentos Relacionados
- Deletion analysis of the CAP-cAMP binding site of the Escherichia coli lactose promoter.
- Ribosome associated protein(s) specifically bind(s) to the upstream activator sequence of the E. coli rrnA P1 promoter.
- Consensus DNA site for the Escherichia coli catabolite gene activator protein (CAP): CAP exhibits a 450-fold higher affinity for the consensus DNA site than for the E. coli lac DNA site.
- The human urokinase-plasminogen activator gene and its promoter.
- Transcription activation at the Escherichia coli uhpT promoter by the catabolite gene activator protein.