Insights into Cell-Free Conversion of CO2 to Chemicals by a Multienzyme Cascade Reaction

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

  • Raushan Kumar Singh
  • Ranjitha Singh
  • Dakshinamurthy Sivakumar
  • Sanath Kondaveeti
  • Taedoo Kim
  • Jinglin Li
  • Bong Hyun Sung
  • Byung Kwan Cho
  • Dong Rip Kim
  • Sun Chang Kim
  • Vipin C. Kalia
  • Yi Heng P. Job Zhang
  • Huimin Zhao
  • Yun Chan Kang
  • Jung Kul Lee

Multienzymatic cascade reactions have garnered the attention of many researchers as an approach for converting CO2 into methanol. The cascade reaction used in this study includes the following enzymes: a formate dehydrogenase (ClFDH), a formaldehyde dehydrogenase (BmFaldDH), and an alcohol dehydrogenase (YADH) from Clostridium ljungdahlii, Burkholderia multivorans, and Saccharomyces cerevisiae, respectively. Because this cascade reaction requires NADH as a cofactor, phosphite dehydrogenase (PTDH) was employed to regenerate the cofactor. The multienzymatic cascade reaction, along with PTDH, yielded 3.28 mM methanol. The key to the success of this cascade reaction was a novel formaldehyde dehydrogenase, BmFaldDH, the enzyme catalyzing the reduction of formate to formaldehyde. The methanol yield was further improved by incorporation of 1-ethyl-3-methylimidazolium acetate (EMIM-Ac), resulting in 7.86 mM of methanol. A 500-fold increase in total turnover number was observed for the ClFDH-BmFaldDH-YADH cascade system compared to the Candida boidinii FDH-Pseudomonas putida FaldDH-YADH system. We provided detailed insights into the enzymatic reduction of CO2 by determining the thermodynamic parameters (Kd and ΔG) using isothermal titration calorimetry. Furthermore, we demonstrated a novel time-dependent formaldehyde production from CO2. Our results will aid in the understanding and development of a robust multienzyme catalyzed cascade reaction for the reduction of CO2 to value-added chemicals.

TidsskriftACS Catalysis
Udgave nummer12
Sider (fra-til)11085-11093
Antal sider9
StatusUdgivet - 2018
Eksternt udgivetJa

ID: 229900279