Structures of L-proline trans-hydroxylase reveal the catalytic specificity and provide deeper insight into
Xiaoyan Hu1, Xue Huang1, Jiao Liu2
1Department of Life Sciences and Medicine, University of Science and Technology of China, Hefei, People's Republic of China.
Abstract:
L-Proline hydroxylase is a member of the non-heme Fe2+/α-ketoglutarate (AKG)-dependent hydroxylase family that catalyzes the reaction from L-proline to hydroxy-L-proline, which is widely used in drug synthesis, biochemistry, food supplementation and cosmetic industries. Here, the first crystal structure of L-proline trans-hydroxylase and its complexes with substrate and product are reported, which reveal the structural basis of trans-cis proline hydroxylation selectivity. Structure comparison with other AKG-dependent hydroxylases identifies conserved amino acid residues, which may serve as signatures of in-line or off-line AKG binding modes in the AKG-dependent enzyme family.
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