A team of researchers have developed novel metagenomic analysis tools that can aid in identifying super heat-resistant enzymes that could be of biotechnological interest. These highly adapted organisms carry special proteins that can significantly increase the dissolution of CO2 while giving them extreme temperature and pH resistance.
The microorganisms that produce these resilient enzymes have evolved to thrive in harsh conditions such as hot springs, volcanos, or salt lakes. This environmental resilience means they are of high interest for capturing CO2 in industrial exhaust streams.
After using the tools to scan millions of genes from metagenomic databases, the team identified a promising biocatalyst candidate originally found in a Japanese hot spring. The highly stable carbonic anhydrase CA-KR1 is a robust enzyme that is particularly adept at enhancing CO2 dissolution and exhibits excellent stability in industrial conditions. The findings of their study are published in Environmental Science & Technology.
"Metagenomic analysis gives us access to a 'pool of proteins' that remains largely unexplored and can unravel enzymes and other proteins of great biotechnological interest, such as the CA-KR1 enzyme we have discovered," said Georgios Skretas at BSRC Fleming.
"More specifically, the enzyme performs exceptionally well under conditions of Hot Potassium Carbonate (HPC) capture technologies, with temperatures exceeding 80 °C and pH levels above 11. It enhances CO₂ capture productivity by 90% at 90 °C compared to standard non-enzymatic methods. It also allows for 90% CO₂ removal at 80 °C, surpassing the performance of standard HPC capture and doubling the initial CO₂ absorption rate at 90 °C," added Ph.D. candidate Konstantinos Rigkos.
"The CA-KR1 enzyme is perhaps the most robust biocatalyst (carbonic anhydrase) for efficient CO₂ capture in HPC conditions reported to date. Its integration in industrial settings holds great promise for accelerating the industrial implementation of biomimetic CO₂ capture—a green, sustainable technology expected to be a 'game changer' in carbon sequestration, significantly contributing to the timely achievement of carbon neutrality," said Post-Doctoral Researcher Dimitra Zarafeta.
The innovative enzyme is already patent-pending and its industrialization could provide necessary innovation in CO2 capture.