Topo II (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption James Berger, with Berkeley Lab's Physical Biosciences Division, produced the first 3-D structural images of a DNA-bound topo II enzyme that's responsible for untangling coiled strands of chromosomes during cell division. Credit Photo by Roy Kaltschmidt, Berkeley Lab, Creative Services Office 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.