Biophysical Journal 90 3

Cover picture: Snapshots from molecular dynamics simulations of four different sphingomyelin bilayers with varying acyl chain length and degree of unsaturation. The molecular species of sphingomyelin (SM) shown in the figure are: 16:0-SM (top left), 16:1-SM (top right), 24:0-SM (bottom left), and 24:1-SM (bottom right). The acyl chains of opposite monolayers have been rendered with small spheres and colored differently (orange/blue), whereas the other parts of SM molecules have been rendered by bonds and colored by atom types. A few selected SM molecules are shown in white to better indicate the enhanced interdigitation in 24:0-SM and 24:1-SM bilayers. See the article by Niemelä et al. on page 851.