Coordinated regulation of gene expression by E ... - Jacobs University

INTRODUCTION
Figure 3: Structural profiles of sigma70 and sigma54 promoter regions.
Comparison of sigma70 specific promoter regions with sigma54 regions show that sigma70 promoters
have more intrinsic curvature and are also more easily deformable than sigma54 promoters [Pedersen,
2000 ].
1.2.2 Gene promoters respond distinctly to changes of
supercoiling
One of the extrinsic determinants of the promoter activity is the superhelical density of
the DNA. Negative supercoiling of the DNA provides the thermodynamic driving force
that is required for unwinding the DNA double helix during the initiation process and it
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