2NW8:
reference: Molecular insights into substrate recognition and catalysis by tryptophan 2,3-dioxygenase., Forouhar F, Anderson JL, Mowat CG, Vorobiev SM, Hussain A, Abashidze M, Bruckmann C, Thackray SJ, Seetharaman J, Tucker T, Xiao R, Ma LC, Zhao L, Acton TB, Montelione GT, Chapman SK, Tong L, Proc Natl Acad Sci U S A. 2007 Jan 9;104(2):473-8. Epub 2006 Dec 29. PMID: 17197414

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