Philipp K Zuber, Nelly Said, Tarek Hilal, Bing Wang, Bernhard Loll, Jorge González-Higueras, César A Ramírez-Sarmiento, Georgiy A Belogurov, Irina Artsimovitch, Markus C Wahl, Stefan H Knauer
RfaH, a paralog of the universally conserved NusG, binds to RNA polymerases (RNAP) and ribosomes to activate expression of virulence genes. In free, autoinhibited RfaH, an α-helical KOW domain sequesters the RNAP-binding site. Upon recruitment to RNAP paused at an ops site, KOW is released and refolds into a β-barrel, which binds the ribosome. Here, we report structures of ops-paused transcription elongation complexes alone and bound to the autoinhibited and activated RfaH, which reveal swiveled, pre-translocated pause states stabilized by an ops hairpin in the non-template DNA...
April 8, 2024: Nature Communications