Biosynthesis of Glucaric Acid by Recombinant Strain of Escherichia coli Expressing Two Different Urinate Dehydrogenases

D-Glucaric acid is an important bio-based building block of polymers and is a high value-added chemical that can be used in a variety of applications. In the present study, the Udh target genes from Pseudomonas putida and Pseudomonas syringae were used together to construct the expression vector pETDuet-2×Udh. The transformants of BL21(DE3) with vector pETDuet-2×Udh was applied to produce glucaric acid from glucuronic acid. After optimization of induction conditions, the highest Udh expression were achieved when 0.4 mmol L-1 isopropyl-β-d–thiogalactoside (IPTG) was added to cell cultures at an OD600 value of 0.6 followed by culture at 26℃ for 6 hours. The production of glucaric acid substantially reached 5.24 ± 0.015 g L-1 in fed-batch cultures in a 30 L tank. In the present study, a new system for glucaric acid production was established, which was more economic and friendly to environment.