4H9Z:
reference: Structural evidence of a productive active site architecture for an evolved quorum-quenching GKL lactonase., Xue B, Chow JY, Baldansuren A, Yap LL, Gan YH, Dikanov SA, Robinson RC, Yew WS, Biochemistry. 2013 Apr 2;52(13):2359-70. doi: 10.1021/bi4000904. Epub 2013 Mar, 19. PMID: 23461395

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