An ideal spacing is required for the control of Class II CRP-dependent promoters by the status of CRP K100

Research output: Contribution to journalArticlepeer-review


  • Ana Écija-Conesa
  • Julia Gallego-Jara
  • Gema Lozano Terol
  • Alan J Wolfe
  • Manuel Cánovas Díaz
  • Teresa de Diego Puente

External organisations

  • University of Murcia
  • University of Birmingham
  • Univ Birmingham Edgbaston
  • Loyola University of Chicago


Transcription activation by the Escherichia coli CRP at Class II promoters is dependent on direct interactions between RNA polymerase and CRP, therefore the spatial proximity between both proteins plays a significant role in the ability of CRP to activate transcription. Using both in vivo and in vitro techniques, here we demonstrate that the CRP K100 positive charge, adjacent to AR2, is required for full promoter activity when CRP is optimally positioned. Accordingly, K100 mediated activation is very position-dependent and our data confirm that the largest impact of the K100 status on transcription activation occurs when the spacing between the CRP binding site and the A2 of the -10 element is 22 bp. From the results of this study and the progress in the understanding about open complex DNA scrunching, we propose that CRP-dependent promoters should now be numbered by the distance from the center of the DNA site for CRP and the most highly conserved base at position 2 of the -10 hexamer in bacterial promoters.


Original languageEnglish
JournalFEMS Microbiology Letters
Issue number20
Publication statusPublished - 11 Nov 2020