2OQX:
reference: The structure of apo tryptophanase from Escherichia coli reveals a wide-open conformation., Tsesin N, Kogan A, Gdalevsky GY, Himanen JP, Cohen-Luria R, Parola AH, Goldgur Y, Almog O, Acta Crystallogr D Biol Crystallogr. 2007 Sep;63(Pt 9):969-74. Epub 2007, Aug 17. PMID: 17704565

This OCA Structure page
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