1V9Z:
reference: A redox-controlled molecular switch revealed by the crystal structure of a bacterial heme PAS sensor., Kurokawa H, Lee DS, Watanabe M, Sagami I, Mikami B, Raman CS, Shimizu T, J Biol Chem 2004 May 7;279(19):20186-93. Epub 2004 Feb 23. PMID: 14982921

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