4FAZ:
reference: Structural and kinetic characterization of two 4-oxalocrotonate tautomerases in Methylibium petroleiphilum strain PM1., Terrell CR, Burks EA, Whitman CP, Hoffman DW, Arch Biochem Biophys. 2013 Sep 1;537(1):113-24. doi: 10.1016/j.abb.2013.06.016., Epub 2013 Jul 4. PMID: 23831510

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