Dipeptide epimerase with a preference for hydrophobic substrates. Catalyzes the epimerization of L-Ala-L-Thr, L-Ala-L-Met, L-Ala-L-His, L-Ala-L-Phe, L-Ala-L-Tyr, L-Ala-L-Trp, L-Ile-L-Ala, L-Ile-L-Ser, L-Ile-L-Met, L-Ile-L-His, L-Ile-L-Phe, L-Ile-L-Tyr, L-Ile-L-Trp, L-Phe-L-Met, L-Phe-L-His, L-Phe-L-Phe, L-Phe-L-Tyr, L-Phe-L-Trp, L-Phe-L-Ser, L-Phe-L-Thr and L-Phe-L-Lys (in vitro). Binds 1 Mg(2+) ion per subunit. Part of a large, functionally divergent protein family. Protein modeling and substrate docking was used to predict the substrate specificity, prior to biochemical analysis. Belongs to the mandelate racemase/muconate lactonizing enzyme family.