4ORS:
reference: High-resolution structures of mutants of residues that affect access to the ligand-binding cavity of human lipocalin-type prostaglandin D synthase., Perduca M, Bovi M, Bertinelli M, Bertini E, Destefanis L, Carrizo ME, Capaldi S, Monaco HL, Acta Crystallogr D Biol Crystallogr. 2014 Aug 1;70(Pt 8):2125-38. doi:, 10.1107/S1399004714012462. Epub 2014 Jul 25. PMID: 25084332

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