4PEJ:
reference: De novo-designed enzymes as small-molecule-regulated fluorescence imaging tags and fluorescent reporters., Liu Y, Zhang X, Tan YL, Bhabha G, Ekiert DC, Kipnis Y, Bjelic S, Baker D, Kelly JW, J Am Chem Soc. 2014 Sep 24;136(38):13102-5. doi: 10.1021/ja5056356. Epub 2014 Sep, 11. PMID: 25209927

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