Biosynthesis of C4-C8 3-Hydroxycarboxylic Acids from Glucose through the Inverted Fatty Acid β-Oxidation by Metabolically Engineered Escherichia coli

• Published in: Biomolecules (Basel, Switzerland) Switzerland), 2024-04, Vol.14 (4), p.449
• Main Authors: Gulevich, Andrey Yu, Skorokhodova, Alexandra Yu, Debabov, Vladimir G
• Format: Article
• Language: English
• Subjects: 3-hydroxycarboxylic acids; Alcohol; Alcohols; Antibiotics; Biosynthesis; Carbon; Carbon sources; Carboxylic acids; Carboxylic Acids - metabolism; Chromosomes; Dehydrogenases; Drug resistance; E coli; Enzymes; Escherichia coli; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; fatty acid β-oxidation; Fatty acids; Fatty Acids - biosynthesis; Fatty Acids - metabolism; Fermentation; Genes; Genetic engineering; Glucose; Glucose - metabolism; Metabolic Engineering; Oxidation; Oxidation-Reduction; Plasmids; Recombinants; Thioesterase
• ISSN: 2218-273X; 2218-273X
• DOI: 10.3390/biom14040449

Inverted fatty acid β-oxidation represents a versatile biochemical platform for biosynthesis by the engineered microbial strains of numerous value-added chemicals from convenient and abundant renewable carbon sources, including biomass-derived sugars. Although, in recent years, significant progress has been made in the production through this pathway of n-alcohols, 1,3-diols, and carboxylic acids and its 2,3-unsaturated derivatives, the potential of the pathway for the biosynthesis of 3-hydroxycarboxylic acids remained almost undisclosed. In this study, we demonstrate the microaerobic production of even-chain-length C4-C8 3-hydroxycarboxylic acids from glucose through the inverted fatty acid β-oxidation by engineered strains. The notable accumulation of target compounds was achieved upon the strong constitutive expression of the genes , , , / , and , which code for the key enzymes catalysing reactions of aerobic fatty acid β-oxidation and thioesterase II, in strains devoid of mixed-acid fermentation pathways and lacking nonspecific thioesterase YciA. The best performing recombinants were able to synthesise up to 14.5 mM of 3-hydroxycarboxylic acids from glucose with a total yield of 0.34 mol/mol and a C4/C6/C8 ratio averaging approximately 63/28/9. The results provide a framework for the development of highly efficient strains and processes for the bio-based production of valuable 3-hydroxycarboxylates from renewable raw materials.