A Molecular Cage (IMAGE) University of California - Los Angeles Caption This is a molecular cage created by designing specialized protein puzzle pieces. Every color represents a separate protein, where cylindrical segments indicate rigid parts and ribbon-like segments indicate flexible parts of each protein chain. The grey sphere in the protein cage was placed there to indicate the empty space in the middle of the container and is not part of the molecular structure. Credit Todd Yeates, Yen-Ting Lai/UCLA Chemistry and Biochemistry 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.