CRP-CENTER-DOT-CAMP-DEPENDENT TRANSCRIPTION ACTIVATION OF THE ESCHERICHIA-COLI PTS P0 PROMOTER BY THE HEAT-SHOCK RNA-POLYMERASE (E-SIGMA(32)) IN-VITRO

The PO promoter of the Escherichia coli pfs operon that is activated d uring growth in the presence of glucose contains a recognition sequenc e for the RNA polymerase holoenzyme containing sigma 70 (E sigma(70)) which is the RNA polymerase holoenzyme responsible for the transcripti on of heat shock genes, and a putative recognition element for E sigma (32), the E sigma(32) was found to be able to transcribe from the pfs PO promoter with in vitro transcription assays using purified RNA poly merase holoenzymes. E sigma(32) and E sigma(70) used the same transcri ptional start site and both RNA polymerases were activated in the pres ence of a cAMP receptor protein (CRP) and cAMP complex (CRP.cAMP). The se results suggest the possibility that the contact between CRP cAMP a nd the alpha subunit of the RNA polymerase can be made regardless of t he kind of sigma subunit that is associated with the core RNA polymera se.