Bioelectrocatalysis uses cellular processes for chemical synthesis

Newswise — Greener and more efficient chemical catalysts are right within our cells.

Catalysts are key components of the chemical reactions that produce chemicals, biofuels and other materials. Catalysts are active in cellular processes too—certain enzymes, when connected to electrodes, can carry out their biological functions in a laboratory chemical reaction—shuttling electrons from one compound to another. In some cases, an entire microbial cell can be used as a catalyst. Such a chemical process is called bioelectrocatalysis.

Bioelectrocatalysis combines the advantages of biocatalysis and electrocatalysis and is a promising method to synthesize value-added chemicals, clean fuels and degradable material. “Bioelectrocatalysis broadens the research fields of traditional organic electrosynthesis and biocatalysis, and researchers are realizing that this an opportunity area for organic electrosynthesis,” says University of Utah chemistry and materials science and engineering professor Shelley Minteer.

Minteer and postdoctoral scholar Hui Chen recently published a review article in Nature Catalysis. This article detailed the structural features and modification methods of enzymes and microbial cells used in bioelectrocatalysis, the mechanism of electron transfer, the role of the electrode, the application of bioelectrocatalysis on the preparation of chemicals, fuels and materials and future directions of bioelectrocatalysis. “We hope to provide useful reference and inspiration for related researchers by summarizing the research progress of bioelectrocatalysis,” Minteer says.  

In the past two years, Minteer, Chen and doctoral candidate Fangyuan Dong have carried out some fruitful works around the synthesis of chiral chemicals by bioelectrocatalysis. On the basis of a previously developed bioelectrocatalytic nitrogen fixation for converting nitrogen to ammonia, an upgraded bioelectrocatalytic nitrogen fixation system was developed to convert gaseous nitrogen to chiral amines and chiral amino acids which are widely used in the preparation of pharmaceuticals and food additives. At the same time as chemical conversion, electrical energy can also be generated. “We hope to synthesize more useful chemicals by bioelectrocatalysis, and further promote the development of organic electrosynthesis,” Chen says.

Several challenges remain to be overcome before the Minteer group’s research can find application in the real world. “One is the design and scaleup of bioelectrocatalytic reactors and electrodes to meet the requirement of bioelectrosynthesis of target chemicals,” Chen says. “The other is the combination of bioelectrocatalytic methods with existing industrial production systems, including the reaction process control and separation of end products.”