3ZTF:
reference: Structure-guided evolution of cyan fluorescent proteins towards a quantum yield of 93%., Goedhart J, von Stetten D, Noirclerc-Savoye M, Lelimousin M, Joosen L, Hink MA, van Weeren L, Gadella TW Jr, Royant A, Nat Commun. 2012 Mar 20;3:751. doi: 10.1038/ncomms1738. PMID: 22434194

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