passages.id: split_8_test_326_passage
passages.type: progene_text
passages.text: Recent data suggest that sigma factor specificity at stress - activated promoters is affected by the interplay of the two RNA polymeraseholoenzymes with additional regulatory factors , such as H-NS , Lrp , CRP , IHF or Fis , that differentially affect transcription initiation by sigmaS or sigma70 in a promoter - specific manner .