1GZG:
reference: Structure of porphobilinogen synthase from Pseudomonas aeruginosa in complex with 5-fluorolevulinic acid suggests a double Schiff base mechanism., Frere F, Schubert WD, Stauffer F, Frankenberg N, Neier R, Jahn D, Heinz DW, J Mol Biol 2002 Jul 5;320(2):237-47. PMID: 12079382

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