4IFR:
reference: The power of two: arginine 51 and arginine 239* from a neighboring subunit are essential for catalysis in alpha-amino-beta-carboxymuconate-epsilon-semialdehyde decarboxylase., Huo L, Davis I, Chen L, Liu A, J Biol Chem. 2013 Oct 25;288(43):30862-71. doi: 10.1074/jbc.M113.496869. Epub, 2013 Sep 9. PMID: 24019523

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