Effect of Overexpression of a Soluble Pyridine Nucleotide Transhydrogenase (UdhA) on the Production of Poly(3-hydroxybutyrate) in Escherichia coli

• Published in: Biotechnology progress Vol. 22; no. 2; pp. 420 - 425
• Main Authors: Sánchez, Ailen M., Andrews, Jared, Hussein, Insiya, Bennett, George N., San, Ka-Yiu
• Format: Journal Article
• Language: English
• Published: USA American Chemical Society 01.03.2006; American Institute of Chemical Engineers
• Subjects: Alcaligenes eutrophus; Biological and medical sciences; Biotechnology; Escherichia coli; Escherichia coli - enzymology; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Enzymologic; Glucose - metabolism; Hydroxybutyrates - metabolism; NAD - metabolism; NADP Transhydrogenases - genetics; NADP Transhydrogenases - metabolism; Polyesters - metabolism; Solubility; Pyridine; Escherichia coli; Production; Gene overexpression; Bacteria; Butyrate(hydroxy)polymer; Enterobacteriaceae
• ISSN: 8756-7938; 1520-6033
• DOI: 10.1021/bp050375u

A soluble pyridine nucleotide transhydrogenase (UdhA) has been used to increase the productivity and yield of PHB in vivo. By inducing a high level of UdhA, which can transfer reducing equivalents between NAD and NADP, we have increased NADPH availability, resulting in high yield and productivity of PHB in Escherichia coli. Coexpression of the phboperon from Alcaligenes eutrophusH16 and the native udhAfrom E. coli from high copy plasmids resulted in an increase in PHB yield from 49 to 66% g of PHB per gram of total cell dry weight and an increase in final concentration from 3.52 to 6.42 g/L; the PHB concentration of the udhA carrying strain is almost twice that of the control strain expressing only the phb operon. The results of this study demonstrate the effectiveness of cofactor manipulation and its application as a tool in metabolic engineering.