DNA (IMAGE) Rutgers University Caption Three conformations of the DNA double helix: A (left), B (center) and left-handed Z (right). Credit David S. Goodsell and RCSB PDB 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.