BioChem - DOS

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

ACS catalysis

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

<P>Multienzymatic cascade reactions have garnered the attention of many researchers as an approach for converting CO<SUB>2</SUB> 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 <I>Clostridium ljungdahlii</I>, <I>Burkholderia multivorans</I>, and <I>Saccharomyces cerevisiae</I>, 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 <I>Candida boidinii</I> FDH-<I>Pseudomonas putida</I> FaldDH-YADH system. We provided detailed insights into the enzymatic reduction of CO<SUB>2</SUB> by determining the thermodynamic parameters (<I>K</I><SUB>d</SUB> and <I>&Delta;<I>G</I></I>) using isothermal titration calorimetry. Furthermore, we demonstrated a novel time-dependent formaldehyde production from CO<SUB>2</SUB>. Our results will aid in the understanding and development of a robust multienzyme catalyzed cascade reaction for the reduction of CO<SUB>2</SUB> to value-added chemicals.</P><BR>[FIG OMISSION]</BR>

2018

American Chemical Society

2155-5435

8

12

pp.11085-11093

10.1021/acscatal.8b02646.s001

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART95106919

https://doi.org/10.1021/acscatal.8b02646.s001

cascade reaction; formaldehyde; methanol; multienzyme; CO2; FDH; FaldDH