Biosynthesis of Suberiс Acid from Glucose through Inverted Fatty Acid β-Oxidation by Recombinant Escherichia coli Strains
摘要
Using directly engineered derivatives of previously constructed adipate-producing Escherichia coli strains MG1655 lacIQ, ∆ackA-pta, ∆poxB, ∆ldhA, ∆adhE, PL-SDφ10-atoB, Ptrc-ideal-4-SDφ10-fadB, ∆fadE, PL-SDφ10-tesB, ∆yciA, Ptrc-ideal-4-SDφ10-fabI, PL-SDφ10-paaJ, ∆aceBAK, ∆glcB and MG1655 lacIQ, ∆ackA-pta, ∆poxB, ∆ldhA, ∆adhE, PL-SDφ10-atoB, Ptrc-ideal-4-SDφ10-fadB, PL-SDφ10-tesB, ∆yciA, Ptrc-ideal-4-SDφ10-fadE, PL-SDφ10-paaJ, ∆aceBAK, ∆glcB, the feasibility of suberic acid biosynthesis from glucose by this bacterium resulting from the reversal of the native fatty acid β-oxidation pathway was demonstrated. The condensation of acetyl-CoA with succinyl-CoA and adipyl-CoA was ensured in recombinants by 3-oxoadipyl-CoA thiolase PaaJ, whereas the putative acetyl-CoA C-acetyltransferase YqeF was unable to catalyze the respective reactions. The biosynthesis of ~60 μM suberic acid was achieved upon significant enhancement in the strains of the expression of the bifunctional (S)-3-hydroxyacyl-CoA dehydrogenase/enoyl-CoA reductase gene, fadB. Subsequent inactivation of succinate dehydrogenase in the strains increased the intracellular availability of succinyl-CoA for the initiation of the first round of cycle reversal and favored an increase in the accumulation of the target compound by the recombinants to ~75 μM. The results provide a framework for the development of highly efficient producing strains for bio-based production of suberic acid from renewable raw materials.