Recently, Biomass Conversion Technology Group led by Prof. ZHAO Zongbao from Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) made a new progress in the research of non-natural cofactor. Researchers successfully constructed a non-natural cofactor and formate driven system with pathway-selective energy transfer. This work was published in Angewandte Chemie International Edition.
Nicotinamide adenosine dinucleotide (NAD) and its reduced form are linked to hundreds of cellular reactions, and fluctuation of NAD(H) level causes global disturbance to cellular metabolism. To over come the limitations of the regulation of natural cofactors, the group led by Prof. ZHAO Zongbao has been working on the research area of non-natural cofactors.
In previous works, bioorthogonal redox catalytic system was constructed with non-natural cofactor dependent oxidoreductase mutants via directed revolution (J. Am. Chem. Soc., 2011, 133, 20857). In addition, cofactor preference of phosphite dehydrogenase was engineered and the molecular basis of cofactor preference was elucidated (ACS Catal., 2019, 9, 1883). Moreover, researchers also constructed non-natural organic acids synthesis system driven by phosphite, selectively transferring energy to the metabolic pathways of bacteria (ACS Catal., 2017, 7, 1977).
In this work, a nicotinamide cytosine dinucleotide (NCD) dependent formate dehydrogenase (FDH*) was obtained through directed evolution, and new bioorthogonal system was built with NCD dependent FDH* and malic enzyme (ME*). Results showed that pyruvate was reductive carboxylated with carbon unit and reducing power from formate. Further, researchers constructed a malate synthesis system driven by formate and NCD in microbe. This work reversed the natural direction of metabolic node of malate, showing great value for redesign of metabolic pathways and selectively regulation the substance and energy metabolism.
Non-natural cofactor and formate driven reductive carboxylation of pyruvate. FDH*: formate dehydrogenase mutant; ME*: malic enzyme mutant; NCD: nicotinamide cytosine dinucleotide. (Image by GUO Xiaojia)
This work was supported by National Natural Science Foundation of China and Dalian Institute of Chemical Physics. (Text and image by GUO Xiaojia)