5NSR:
reference: Structures of RNA Polymerase Closed and Intermediate Complexes Reveal Mechanisms of DNA Opening and Transcription Initiation., Glyde R, Ye F, Darbari VC, Zhang N, Buck M, Zhang X, Mol Cell. 2017 Jul 6;67(1):106-116.e4. doi: 10.1016/j.molcel.2017.05.010. Epub, 2017 Jun 1. PMID: 28579332

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