2M8G:
reference: Structure, function, and tethering of DNA-binding domains in sigma transcriptional activators., Vidangos N, Maris AE, Young A, Hong E, Pelton JG, Batchelor JD, Wemmer DE, Biopolymers. 2013 Jul 2. doi: 10.1002/bip.22333. PMID: 23818155

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