Crystal structure of bacterial L-arabinose 1-dehydrogenase in complex with L-arabinose and NADP.

Crystal structure of bacterial L-arabinose 1-dehydrogenase in complex with L-arabinose and NADP. Biochem Biophys Res Commun. 2020 Sep 10;530(1):203-208 Authors: Yoshiwara K, Watanabe S, Watanabe Y Abstract L-Arabinose 1-dehydrogenase (AraDH) is responsible for the first step of the non-phosphorylative L-arabinose pathway from bacteria, and catalyzes the NAD(P)+-dependent oxidation of L-arabinose to L-arabinonolactone. This enzyme belongs to the so-called Gfo/Idh/MocA protein superfamily, but has a very poor phylogenetic relationship with other functional members. We previously reported the crystal structures of AraDH without a ligand and in complex with NADP+. To clarify the underlying catalytic mechanisms in more detail, we herein elucidated the crystal structure in complex with L-arabinose and NADP+. In addition to the previously reported five amino acid residues (Lys91, Glu147, His153, Asp169, and Asn173), His119, Trp152, and Trp231 interacted with L-arabinose, which were not found in substrate recognition by other Gfo/Idh/MocA members. Structure-based site-directed mutagenic analyses suggested that Asn173 plays an important role in catalysis, whereas Trp152, Trp231, and His119 contribute to substrate binding. The preference of NADP+ over NAD+ was significantly subjected by a pair of Ser37 and Arg38, whose manners were similar to other Gfo/Idh/MocA members. PMID: 32828286 [PubMed - as supplied by publisher]
Source: Biochemical and Biophysical Research communications - Category: Biochemistry Authors: Tags: Biochem Biophys Res Commun Source Type: research