关键词: UDP-葡萄糖醛酸, UDP-葡萄糖, 双酶偶联

Abstract: Uridine diphosphate (UDP)-glucuronic acid is an important sugar donor in cells, which participates in many metabolic pathways and is also an important sugar donor for glycosylation in vitro. However, its high price and complicated process limit its large-scale use and cannot meet the production demand. Based on this, UDP-glucose was oxidized to UDP-glucuronic acid by double-enzyme coupling method, and the synthesis of reaction products was studied. With UDP-glucose as substrate and nicotinamide adenine dinucleotide (NAD+) as cofactor, UDP-glucuronic acid was synthesized by using UDP-glucose dehydrogenase (UGD) from Streptococcus pyogenes and lactate dehydrogenase (LDH) from pigs, and the products were detected by high performance liquid chromatography, mass spectrometry and nuclear magnetic resonance (1H NMR) to determine the structure and yield of the products. The results showed that UDP-glucuronic acid was the product of oxidation of UDP-glucose by double-enzyme coupling method. Under the action of UGD, UDP-glucose was oxidized to UDP-glucuronic acid, and the cofactor NAD+ was recycled under the action of LDH, which reduced the feedback inhibition of the high-energy product reduced nicotinamide adenine dinucleotide (NADH) on the reaction. The yield of the product was about 60.17%. The research increased the production of UDP-glucuronic acid, which provided a new idea for the subsequent industrial preparation.

Key words: UDP-glucuronic acid, UDP-glucose, double-enzyme coupling