5UI5:
reference: Crystal structure of Aquifex aeolicus sigmaN bound to promoter DNA and the structure of sigmaN-holoenzyme., Campbell EA, Kamath S, Rajashankar KR, Wu M, Darst SA, Proc Natl Acad Sci U S A. 2017 Feb 21. pii: 201619464. doi:, 10.1073/pnas.1619464114. PMID: 28223493

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