3NED:
reference: Generation of longer emission wavelength red fluorescent proteins using computationally designed libraries., Chica RA, Moore MM, Allen BD, Mayo SL, Proc Natl Acad Sci U S A. 2010 Nov 23;107(47):20257-62. doi:, 10.1073/pnas.1013910107. Epub 2010 Nov 8. PMID: 21059931

This OCA Structure page
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