Crystal structures of Klebsiella oxytoca ribitol dehydrogenase in complex with NAD + , d ‐allose, or d ‐allulose reveal insight into substrate recognition
Year: 2026
Type: article
Abstract: Recombinant NAD + ‐dependent ribitol dehydrogenase derived from Klebsiella oxytoca (KoRdh) exhibits activity toward both ribitol and allitol. KoRdh catalyzes the NAD + ‐dependent oxidation of allitol to d ‐allulose and the NADH‐dependent reduction of d ‐allulose to allitol. Notably, the flexible loop of KoRdh undergoes conformational changes upon NAD + and substrate binding. To elucidate the flexible loop's role in substrate recognition, we determined the X‐ray structures of KoRdh alone and in complexes with NAD + , d ‐allulose, or d ‐allose. Although d ‐allose is an aldose and not a substrate of KoRdh, it binds to KoRdh in the pyranose form, revealing the location of the substrate‐binding site. Based on these structures, we propose a substrate recognition mechanism for KoRdh. Impact statement This research reveals an insight into a substrate recognition mechanism in the flexible region of ribitol dehydrogenase. Because ribitol dehydrogenase is a member of the short‐chain reductases/oxidases (SDR) family, the current study will provide further insight into related enzymes that harbor the flexible region.
Source: FEBS Letters
Institution: Kagawa University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7155158533