Protein fold (IMAGE) Rutgers University Caption This image shows a fold (shape) that may have been one of the earliest proteins in the evolution of metabolism. Credit Vikas Nanda/Rutgers University Usage Restrictions None 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.