A Metal-Dependant Formate Dehydrogenase Advances the Formate Bio-economy

In this manuscript a multi-subunit metal dependent FDH is functionally expressed in a strain of E. coli engineered to assimilate all energy and biomass from formate. The replacement of the previously described FDH with this new, faster FDH allows for improved growth parameters rivaling natural formatotrophs for the first time. This new, robsulty growing formatotrophic E. coli was engineered to produce mevalonate and achieved the highest reported titer for any bioproduct from formate in fed batch mode. Finally the authors explored bioproducion from electrochemically-derived and lignin-derived formate, demonstrating the first example of a bioproduct produced using liginin-derived formate as a feedstock.

本研究中，一款多亚基金属依赖型甲酸脱氢酶（FDH）在经工程改造的大肠杆菌（E. coli）菌株中实现功能性表达，该菌株可通过甲酸同化获取全部能量与生物质。将此前报道的甲酸脱氢酶替换为这款新型高活性的甲酸脱氢酶后，菌株生长参数得到显著优化，首次实现了可与天然甲酸营养型微生物媲美的生长水平。这款生长稳健的新型甲酸营养型大肠杆菌经工程改造可生产甲羟戊酸，在补料分批培养模式下，达到了以甲酸为底物生产各类生物制品的最高已报道滴度。最后，研究团队探究了以电化学衍生甲酸与木质素衍生甲酸为底物的生物合成过程，首次证实了以木质素衍生甲酸为原料生产生物制品的可行性实例。