The role of DNA conformation in transcriptional initiation and activation in Escherichia coli.

Transcription activation in prokaryotes relies on a multitude of molecular mechanisms. Many of them use DNA bending or other deformations of the DNA to control the rate of transcription initiation. All steps of initiation involve a particular transconformation reaction of the DNA and can be controlled individually by activators. This review discusses the thermodynamic and kinetic basis of transcription initiation and illustrates the strategies used by activators. Particular emphasis is given to mechanisms that necessitate DNA-bending by the activator.