Supercomplex CIII2CIV. (IMAGE) Institute of Science and Technology Austria Caption When assembled into a supercomplex, the two parts of CIII2CIV are held together by a molecule that acts like a fishhook. This optimizes the cell metabolism. © Verena Resch Luminous Lab/IST Austria Credit Verena Resch Luminous Lab / IST Austria Usage Restrictions Verena Resch Luminous Lab / IST Austria License Original 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.