Incomplete Protein Digestion (IMAGE) University of Massachusetts Amherst Caption Chien and Vass's recent work shows that in some bacteria, short forms of a specialized replication factor, the protein DnaX, are made by proteolysis, an unexpected finding and evidence of convergent evolution. Two forms are generated through radically different mechanisms, suggesting for the first time that both long and short forms are required for all bacteria. Credit Peter Chien, UMass Amherst 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.