5ZX2

Mycobacterium tuberculosis RNA polymerase transcription initiation complex with ECF sigma factor sigma H and 7nt RNA

Summary for 5ZX2

• Entry DOI: 10.2210/pdb5zx2/pdb
• Descriptor: DNA-directed RNA polymerase subunit alpha, DNA-directed RNA polymerase subunit beta, DNA-directed RNA polymerase subunit beta', ... (10 entities in total)
• Functional Keywords: mycobacterium tuberculosis, rna polymerase, sigma h, transcription initiation, transcription-dna-rna complex, transcription/dna/rna
• Biological source: Mycobacterium tuberculosis H37Rv; More
• Total number of polymer chains: 9
• Total formula weight: 425172.84

Authors

Li, L.,Zhang, Y. (deposition date: 2018-05-17, release date: 2019-03-20, Last modification date: 2023-11-22)

Primary citation

Li, L.,Fang, C.,Zhuang, N.,Wang, T.,Zhang, Y.
Structural basis for transcription initiation by bacterial ECF sigma factors.
Nat Commun, 10:1153-1153, 2019

PubMed Abstract: Bacterial RNA polymerase employs extra-cytoplasmic function (ECF) σ factors to regulate context-specific gene expression programs. Despite being the most abundant and divergent σ factor class, the structural basis of ECF σ factor-mediated transcription initiation remains unknown. Here, we determine a crystal structure of Mycobacterium tuberculosis (Mtb) RNAP holoenzyme comprising an RNAP core enzyme and the ECF σ factor σ (σ-RNAP) at 2.7 Å, and solve another crystal structure of a transcription initiation complex of Mtb σ-RNAP (σ-RPo) comprising promoter DNA and an RNA primer at 2.8 Å. The two structures together reveal the interactions between σ and RNAP that are essential for σ-RNAP holoenzyme assembly as well as the interactions between σ-RNAP and promoter DNA responsible for stringent promoter recognition and for promoter unwinding. Our study establishes that ECF σ factors and primary σ factors employ distinct mechanisms for promoter recognition and for promoter unwinding.

PubMed: 30858373
DOI: 10.1038/s41467-019-09096-y

Experimental method

X-RAY DIFFRACTION (2.8 Å)