Work

Biosynthesis of poly(3-hydroxybutyrate-co-lactate) using an NADH regeneration strategy in E. coli

Year: 2025

Type: article

Abstract: In this study, a platform was constructed for the efficient biosynthesis of a lactate-based copolymer using a phosphite dehydrogenase (PtxD)-based NADH regeneration strategy. PtxD catalyzes the conversion of phosphite to phosphate while reducing NAD + to NADH. The latter is an essential cofactor for lactate synthesis in Escherichia coli . This strategy allows the decoupling of NADH regeneration from carbon metabolism flow, providing sufficient NADH for lactate synthesis. Different concentrations of isopropyl β-d-1-thiogalactopyranoside (IPTG) were used to control the intensity of PtxD expression, and the lactate fraction in the copolymer synthesized by the engineered strain ranged from 6.2–16.7 mol%. The ptxD gene was integrated into the genome of strain WJPCTP-01, which successfully synthesized 3.24 g/L P(3HB- co -23.0 mol% LA) and 2.23 g/L P(3HB- co -39.0 mol% LA) using glucose and xylose as substrates, respectively, in shake flask cultures. In 5 L bioreactor fermentations, the titer of P(3HB- co -41.3 mol% LA) reached 8.57 g/L, with a synthesis rate of 0.12 g/L/h when xylose was used as a substrate. These findings indicate that the PtxD-based NADH regeneration strategy enhances lactate synthesis without any significant negative impact on bacterial growth or the synthesis of P(3HB- co -LA).

Source: BioDesign Research

DOI: 10.1016/j.bidere.2025.100027

Authors: Ju Wu, Xuan Gong, Pengye Guo, Yanzhe Shang, Yuanchan Luo, Hui Wu

Institutions: East China University of Science and Technology, State Key Laboratory of Bioreactor Engineering, Dalian University of Technology, China National Light Industry Council

Language: English

Topic: biodegradable polymer synthesis and properties

Subfield: Biomaterials

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,500

Funders: National Natural Science Foundation of China, Science and Technology Commission of Shanghai Municipality, State Key Laboratory of Bioreactor Engineering, Fundamental Research Funds for the Central Universities