6EYD:
reference: The Core and Holoenzyme forms of RNA Polymerase from Mycobacterium smegmatis., Kouba T, Pospisil J, Hnilicova J, Sanderova H, Barvik I, Krasny L, J Bacteriol. 2018 Nov 26. pii: JB.00583-18. doi: 10.1128/JB.00583-18. PMID: 30478083

This OCA Structure page
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