9GDP

Cryo-EM structure of Vibrio cholerae RNA polymerase holoenzyme bound to an ompU promoter DNA fragment and 5-mer RNA

Summary for 9GDP

• Entry DOI: 10.2210/pdb9gdp/pdb
• EMDB information: 51274
• Descriptor: DNA-directed RNA polymerase subunit beta, MAGNESIUM ION, DNA-directed RNA polymerase subunit beta', ... (10 entities in total)
• Functional Keywords: rna polymerase, open promoter complex, ompu, vibrio cholerae, transcription
• Biological source: Vibrio cholerae O395; More
• Total number of polymer chains: 10
• Total formula weight: 539321.64

Authors

Alcaide-Jimenez, A.,Baudin, F.,Canals, A.,Machon, C.,Murciano, B.,Fabrega-Ferrer, M.,Bantysh, O.,Perez-Luque, R.,Krukonis, E.S.,Muller, C.W.,Coll, M. (deposition date: 2024-08-06, release date: 2025-12-17, Last modification date: 2026-01-28)

Primary citation

Alcaide-Jimenez, A.,Canals, A.,Baudin, F.,Machon, C.,Fabrega-Ferrer, M.,Bantysh, O.,Perez-Luque, R.,Murciano, B.,Mohammad, A.A.,Rowse, M.J.,Ferracciolo, J.M.,Krukonis, E.S.,Muller, C.W.,Coll, M.
Structures of Vibrio cholerae transcription complexes reveal how ToxR and TcpP recruit the RNA polymerase and activate virulence genes.
Sci Adv, 12:eadx9680-eadx9680, 2026

PubMed Abstract: Activation of virulence in , the etiological agent of cholera disease, is mediated by two transmembrane one-component signal-transduction proteins, ToxR and TcpP, which are also transcription factors. Using cryo-electron microscopy, we have solved five structures of the and transcription activation complexes, including the RNA polymerase (RNAP) holoenzyme, promoter DNAs, transcribed RNA, and their corresponding transcription factors, ToxR or TcpP and ToxR-TcpP, respectively. Activation is achieved through the interaction of ToxR or TcpP with the α-C-terminal repeat domain of RNAP where a single residue of the activator, a phenylalanine, appears to be the most critical contact, as confirmed by mutagenesis. No interactions of the transcription factors were observed with other subunits of the RNAP, i.e., the σ subunit as it occurs in the structurally related PhoB family of two-component transcription factors. The structures, and their comparison with our previously solved DNA promoter-ToxR x-ray structures, unveil the molecular mechanism of cholera virulence gene activation.

PubMed: 41533787
DOI: 10.1126/sciadv.adx9680

Experimental method

ELECTRON MICROSCOPY (2.6 Å)