Enzyme converts carbon dioxide into hydrogen storage

The Gwangju Eco-friendly Energy Study Center’s Dr. Min Kyung-sun led a research team that discovered a novel enzyme that creates formic acid, a substance used to store hydrogen, from carbon dioxide, according to a report from the Korea Institute of Energy Research.

Formic acid, a naturally occurring compound in ants, inhibits bacteria and controls the hydrogen ion index. As a result, it is employed in a variety of industries, including food processing, preservatives, and snow removal agents. Recently, attention has been focused on using LOHC (Liquid Organic Hydrogen Carrier), which stores and delivers hydrogen in conjunction with a third substance as opposed to a sizable specific container.

Carbon dioxide is produced during the manufacturing of formic acid by the thermochemical reaction of fossil fuels, and the carbon dioxide electrochemical reaction demands improved performance and durability. In contrast, the naturally occurring carbon dioxide reductase-based technique for making formic acid may use carbon dioxide directly and can selectively manufacture just 100% formic acid without any byproducts. However, only 15 species of carbon dioxide reductase enzymes have been identified in nature.

By using genome-mining based on a genetic database to identify a novel carbon dioxide reductase that stores carbon dioxide as formic acid, the study team created a sourcing technique for creating hydrogen storage materials from greenhouse gases.

By examining the protein sequence of a carbon dioxide reductase with known activity, examining the sequence and similarity in the gene database, and predicting and examining the active site’s structure, the study team was able to identify a novel carbon dioxide reductase. An enzyme reaction system was built to manufacture formic acid, a hydrogen storage substance, from carbon dioxide by studying the carbon dioxide reduction activity and reaction properties using the found enzyme.

The three recently identified carbon dioxide reductases may be manufactured in large quantities using a recombinant protein expression method and can convert carbon dioxide into formic acid, which can be utilized as a hydrogen storage material.

In addition, compared to electrochemical conversion and chemical catalyst conversion technologies, which are currently competitive technologies for producing formic acid from carbon dioxide, the biocatalyst enzyme has a lower reaction temperature and lower energy requirements, making it possible to develop an eco-friendly, low-energy process. Additionally, because of its great substrate specificity, it has the benefit of being able to create formic acid with 100% selectivity and no byproducts like carbon monoxide.

This technique has created a brand-new method for producing carbon dioxide-based hydrogen storage materials while also reducing greenhouse gas emissions.

Genetic and structural information is a highly significant tool for locating activities that have been challenging to detect in nature, according to Dr. Min Kyung-sun. We anticipate that it will significantly aid in bringing this about.

The worldwide scientific publication “Bioresource Technology” published the study’s findings.