Work

Engineering of the glucose uptake system to increase 2,4-Dihydroxybutyric acid production in Escherichia coli

Year: 2026

Type: article

Abstract: 2,4-Dihydroxybutyric acid (DHB) is a promising C 4 platform compound for the synthesis of methionine analogues and biodegradable polymers. However, aerobic DHB production from glucose in Escherichia coli involves transient acetate overflow prior to product synthesis, which could be challenging for process scalability. Therefore, we engineered Escherichia coli K-12 MG1655 for optimized DHB production by replacing the phosphotransferase system mediated glucose uptake with the galactose permease GalP, coupled to ATP-dependent phosphorylation via endogenous glucokinase. In combination with targeted deletions of malate- and fumarate-consuming reactions, we obtained a strain with enhanced flux through the tricarboxylic acid (TCA) cycle and pentose phosphate pathway leading to improved NADPH availability and increased anaplerotic activity, as revealed by 13 C metabolic flux analyses. Deletion of the mdh gene encoding for the cytosolic malate dehydrogenase further promoted DHB formation. The resulting strain achieved DHB yields up to 0.20 mol mol -1 (2.43 g L -1 ), a 4-fold increase compared to the wildtype background (0.05 mol mol -1 , 0.60 g L -1 ), under aerobic conditions while suppressing acetate formation. Together, these results demonstrate that GalP-mediated glucose uptake and engineering of the TCA cycle provide a robust metabolic framework for efficient DHB biosynthesis and establish a foundation for further process and pathway development.

Source: Metabolic Engineering Communications

DOI: 10.1016/j.mec.2026.e00276

Authors: T.A. Stefanie Nguyen, Ceren Alkim, Nadine Ihle, Thomas Walther, Cláudio J.R. Frazão

Institutions: Technische Universität Dresden, Centre National de la Recherche Scientifique, Institut National des Sciences Appliquées de Toulouse, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Toulouse Biotechnology Institute, Bio & Chemical Engineering

Language: English

Topic: Microbial Metabolic Engineering and Bioproduction

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: gold

Estimated APC paid: $4,040

Funders: European Commission, Deutsche Forschungsgemeinschaft