1,6-Hexanediol is widely used in the fields of polyester polyols and UV-curable materials, etc.However, the traditional chemical synthesis is mainly monopolised by foreign countries with high technological barriers, and the preparation of biobased hexanediols in the context of carbon neutrality has received wide attention.The aim of this study was to construct an efficient hexanediol synthesis pathway in Escherichia coli by component-adapted assembly using biobased adipic acid as the raw material, with fermentation enhancement to increase the yield of biobased 1,6-hexanediol and its conversion rate.The optimal fermentation strain was constructed by mining the aldo-keto reductase isozyme and assembled with the carboxylic acid reductase from Mycolicibacterium smegmatis MC2 155, and the yield of 1,6-hexanediol was increased by 6.4-fold compared with that of the original strain to reach the titer 61.8 mg/L.On the basis of the fermentation enhancement study, the optimal conditions were determined to be the TB medium and the concentration of the substrate 10 g/L, induction time of 2.5 h, and initial sugar concentration of 8 g/L, at which the yield of 1,6-hexanediol reached 818.16 mg/L, which was 84.7-fold higher than that of the initial strain, and the conversion rate reached 85%.This study provides a new idea for the biosynthesis of 1,6-hexanediol.
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