3B8U:
reference: Residues Asp164 and Glu165 at the substrate entryway function potently in substrate orientation of alanine racemase from E. coli: Enzymatic characterization with crystal structure analysis., Wu D, Hu T, Zhang L, Chen J, Du J, Ding J, Jiang H, Shen X, Protein Sci. 2008 Jun;17(6):1066-76. Epub 2008 Apr 23. PMID: 18434499

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