2WHS:
reference: Reverse pH-dependence of chromophore protonation explains the large Stokes shift of the red fluorescent protein mKeima., Violot S, Carpentier P, Blanchoin L, Bourgeois D, J Am Chem Soc. 2009 Aug 5;131(30):10356-7. PMID: 19722611

This OCA Structure page
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