1F98:
reference: Coupling of hydrogen bonding to chromophore conformation and function in photoactive yellow protein., Brudler R, Meyer TE, Genick UK, Devanathan S, Woo TT, Millar DP, Gerwert K, Cusanovich MA, Tollin G, Getzoff ED, Biochemistry 2000 Nov 7;39(44):13478-86. PMID: 11063584

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