A comparison of branch-chained diphytanoylphosphatidylcholine (DPhPC) and straight-chained dipalmitoylphosphatidylcholine (DPPC) for their dynamics in the bilayers is made using 10 ns molecular dynamics simulations in the microcanonical ensemble. It is demonstrated that DPhPC molecules, compared with DPPC, indeed have slower wobbling, rotational, and translational motions by a factor of 2-3, whereas slightly faster headgroup rotation. The revision of the lipid dynamics due to chain branching is similar to that observed by the addition of cholesterol. (C) 2004 Elsevier B.V. All rights reserved.