2GX0:
reference: Structural characterization of the photoswitchable fluorescent protein Dronpa-C62S., Nam KH, Kwon OY, Sugiyama K, Lee WH, Kim YK, Song HK, Kim EE, Park SY, Jeon H, Hwang KY, Biochem Biophys Res Commun. 2007 Mar 23;354(4):962-7. Epub 2007 Jan 24. PMID: 17276392

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