Construction of reductive pathway in Saccharomyces cerevisiae for effective succinic acid fermentation at low pH value

• Published in: Bioresource technology 2014-03, Vol.156, p.232-239
• Main Authors: Yan, Daojiang, Wang, Caixia, Zhou, Jiemin, Liu, Yilan, Yang, Maohua, Xing, Jianmin
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Bioreactors; Bioreactors - microbiology; Biotechnology; Biotin - pharmacology; Calcium Carbonate - pharmacology; Construction; Enzyme Assays; Fermentation - drug effects; Fundamental and applied biological sciences. Psychology; Gene Deletion; Glucose; Glucose - metabolism; Glycerol-3-Phosphate Dehydrogenase (NAD+) - genetics; Hydrogen-Ion Concentration; Low pH; Metabolic Engineering - methods; Metabolic Networks and Pathways - drug effects; Methods. Procedures. Technologies; Microbial engineering. Fermentation and microbial culture technology; Oxidation-Reduction - drug effects; Pathways; Reducing power; Reductive pathway; Saccharomyces cerevisiae; Saccharomyces cerevisiae - drug effects; Saccharomyces cerevisiae - enzymology; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - genetics; Strain; Succinic acid; Succinic Acid - metabolism; Urea - pharmacology
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2014.01.053

•Metabolic engineering was developed to improve succinate production in yeast.•Reductive pathway was efficient for improving succinate yield.•Succinate production was improved by the deletion of GPD1.•Succinate yield was regulated by urea and biotin levels.•Succinic acid could be effectively produced at pH 3.8 in batch bioreactor. Succinic acid is an important precursor for the synthesis of high-value-added products. Saccharomyces cerevisiae is a suitable platform for succinic acid production because of its high tolerance towards acidity. In this study, a modified pathway for succinate production was established and investigated in S. cerevisiae. The engineered strain could produce up to 6.17±0.34g/L of succinate through the constructed pathway. The succinate titer was further improved to 8.09±0.28g/L by the deletion of GPD1 and even higher to 9.98±0.23g/L with a yield of 0.32mol/mol glucose through regulation of biotin and urea levels. Under optimal supplemental CO2 conditions in a bioreactor, the engineered strain produced 12.97±0.42g/L succinate with a yield of 0.21mol/mol glucose at pH 3.8. These results demonstrated that the proposed engineering strategy was efficient for succinic acid production at low pH value.