Abstract
Bilirubin IXα (BR) offers health benefits in cardiovascular health, stroke, diabetes and metabolic syndrome. BR is mainly extracted from pig bile, bringing potential risks due to infectious viruses. In this study, an efficient pathway for BR biosynthesis was constructed by overexpression of heme oxygenase (HO1) and biliverdin reductase (BvdR) in Escherichia coli. Co-expression of 5-aminolevulinic acid (ALA) dehydratase improved BR production by the recombinant E. coli. In addition, glutamate supplementation in culture media enhanced BR production. Interestingly, it was discovered that ALA exhibited inhibitory effects on HO1 activity and reduced BR production. Culture conditions including post-induction temperature, IPTG concentration, pH of TB media and induction start time were optimized. Finally, fed-batch fermentation was carried out for the strain SH2, producing a BR titer of 62.1 mg/L in a 20 L bioreactor. This study lays foundation for future scalable production of BR in recombinant E. coli.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call