5W19:
reference: The crystal structure of Proteus vulgaris tryptophan indole-lyase complexed with oxindolyl-L-alanine: implications for the reaction mechanism., Phillips RS, Buisman AA, Choi S, Hussaini A, Wood ZA, Acta Crystallogr D Struct Biol. 2018 Aug 1;74(Pt 8):748-759. doi:, 10.1107/S2059798318003352. Epub 2018 Jul 24. PMID: 30082510

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