4P1Q:
reference: Replacement of Highly Conserved E222 by the Photostable Non-photoconvertible Histidine in GFP., Auerbach D, Klein M, Franz S, Carius Y, Lancaster CR, Jung G, Chembiochem. 2014 Jul 7;15(10):1404-8. doi: 10.1002/cbic.201402075. Epub 2014 Jun, 11. PMID: 24919579

This OCA Structure page
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