The Research On Whole-Cell Biosynthesis Of 2,5-Furandicarboxylic Acid From 5-Hydroxymethylfurfural

2,5-furandicarboxylic acid?FDCA?has broad application prospects as a class of dicarboxylic acids.Because FDCA has similar structure and functional groups to traditional petroleum-based monomeric terephthalic acid.It can be used as a new type of renewable bio-based monomer to replace terephthalic acid to produce polymer materials such as polyester and polyurethane.At present,FDCA can be synthesized by different route and starting materials,for example,from citric acid,furan,hexose diacid?galactoic acid and glucose diacid?,diglycolic acid and 5-hydroxymethylfurfural?HMF?.But each of them has its own advantages and disadvantages.For example,in the tannic acid route,the raw material has a lower price than other raw,but the isomer of FDCA is easily produce during the reaction,which causes great difficulty in separation of product and is not suitable for industrial-scale application;Although the diacid route has the same low raw material cost as the tannic acid route,it is easier to product carbonize by-products and isomerization by-products during the reaction process.So it is more difficult to separate pure products and is not suitable for industrial production too.Compared with the above routes,the HMF route based on renewable biomass resources is considered to be the most promising route,and has attracted more and more researchers'attention in recent years^[1],[2].Therefore,in this study,we prepared to synthesize FDCA using whole-cell catalysis by R.ornithinolytica BF60.First,the HmfT1 gene?ADE20411.1?and the Mrad2831₄728 gene?ACB26689.1?gene were used to promote the transfer of HMF into R.ornithinolytica BF60cells,forcing the cells to accelerate the conversion of HMF into HMF acid.Subsequently,HmfH was homologously modeled by Discovery Studio 2017 software,followed by molecular docking of HmfH and substrate HMF acid.Then,strains were strained with HMF in different concentration and combined with high-throughput screening technology to screen for the strains that can continue to metabolize to produce FDCA under high concentrations of HMF,which will lay the foundation for the industrial production of FDCA by R.ornithinolytica BF60.In addition,R.ornithinolytica BF60 was immobilized with immobilization reagents such as sodium alginate,and the immobilization conditions and fermentation conditions were optimized through the selection of immobilization systems and orthogonal experiments.Finally,under the optimal conditions obtained,the immobilized cells can be reused three times,and the total yield can reach 165.94 mmol/L,which is much better than the early one,which is used once and yield is less than 10 mmol/L.