4ORN:
reference: Hidden photoinduced reactivity of the blue fluorescent protein mKalama1., Vegh RB, Bloch DA, Bommarius AS, Verkhovsky M, Pletnev S, Iwai H, Bochenkova AV, Solntsev KM, Phys Chem Chem Phys. 2015 Mar 25. PMID: 25805012

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