Construction of a novel UDP-rhamnose regeneration system by a two-enzyme reaction system and application in glycosylation of flavonoid

In summary, we provided a novel fusion enzyme (VvRHM-NRS), which was NADPH-independent and could convert UDP-glucose to UDP-rhamnose with NADH self-sufficient. A cofactor self-sufficient UDP-rhamnose regeneration system was developed by VvRHM-NRS coupled with GmSUS. By optimizing coupled reaction conditions, a total of 0.57 mM UDP-rhamnose was generated from sucrose, NAD+, and UDP. This synergistic system provides a green chemistry approach for the UDP-rhamnose regeneration in glycosylation of flavonoids and other bioactive substances.