2G7B:
reference: Protein design: reengineering cellular retinoic acid binding protein II into a rhodopsin protein mimic., Vasileiou C, Vaezeslami S, Crist RM, Rabago-Smith M, Geiger JH, Borhan B, J Am Chem Soc. 2007 May 16;129(19):6140-8. Epub 2007 Apr 21. PMID: 17447762

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