2I9V:
reference: Structural role of tyrosine 98 in photoactive yellow protein: effects on fluorescence, gateway, and photocycle recovery., Kyndt JA, Savvides SN, Memmi S, Koh M, Fitch JC, Meyer TE, Heyn MP, Van Beeumen JJ, Cusanovich MA, Biochemistry. 2007 Jan 9;46(1):95-105. PMID: 17198379

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