Image (IMAGE) University of Tsukuba Caption Researchers from the University of Tsukuba have identified a new type of carbonic anhydrase enzyme that can convert CO2 to HCO3- without the use of a metal ion. This discovery not only increases our understanding of how this essential family of enzymes work, but could also be applied to artificial synthesis to help generate renewable energy sources in the future. Credit University of Tsukuba Usage Restrictions Unauthorized use is prohibited License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.