5UI8

structure of sigmaN-holoenzyme

Summary for 5UI8

• Entry DOI: 10.2210/pdb5ui8/pdb
• Descriptor: DNA-directed RNA polymerase subunit alpha, DNA-directed RNA polymerase subunit beta, DNA-directed RNA polymerase subunit beta', ... (7 entities in total)
• Functional Keywords: bacterial rna polymerase sigman-holoenzyme, transcription
• Biological source: Escherichia coli O157:H7; More
• Total number of polymer chains: 6
• Total formula weight: 443682.41

Authors

Darst, S.A.,Campbell, E.A. (deposition date: 2017-01-13, release date: 2017-02-22, Last modification date: 2023-10-04)

Primary citation

Campbell, E.A.,Kamath, S.,Rajashankar, K.R.,Wu, M.,Darst, S.A.
Crystal structure of Aquifex aeolicus sigma (N) bound to promoter DNA and the structure of sigma (N)-holoenzyme.
Proc. Natl. Acad. Sci. U.S.A., 114:E1805-E1814, 2017

PubMed Abstract: The bacterial σ factors confer promoter specificity to the RNA polymerase (RNAP). One alternative σ factor, σ, is unique in its structure and functional mechanism, forming transcriptionally inactive promoter complexes that require activation by specialized AAA ATPases. We report a 3.4-Å resolution X-ray crystal structure of a σ fragment in complex with its cognate promoter DNA, revealing the molecular details of promoter recognition by σ The structure allowed us to build and refine an improved σ-holoenzyme model based on previously published 3.8-Å resolution X-ray data. The improved σ-holoenzyme model reveals a conserved interdomain interface within σ that, when disrupted by mutations, leads to transcription activity without activator intervention (so-called bypass mutants). Thus, the structure and stability of this interdomain interface are crucial for the role of σ in blocking transcription activity and in maintaining the activator sensitivity of σ.

PubMed: 28223493
DOI: 10.1073/pnas.1619464114

Experimental method

X-RAY DIFFRACTION (3.76 Å)