Cover picture: Superposition of the 156 best-fitted conformations of kyotorphin obtained from constant-pH MD simulations (lines; carbon atoms in green) onto the morphine structure (sticks; carbon atoms in yellow). Kyotorphin can fulfill key structural constraints needed to bind to a μ-like opioid receptor. All hydrogen atoms are omitted for clearness. See the article by Machuqueiro and Baptista on page 1836.