Gel machines constructed from chemically cross-linked actins and myosins

We report an ATP fueled soft gel machine reconstructed from muscle proteins of actin and myosin. Chemically cross-linked actin gel filaments, several decade times the length of native actin filaments (F-actin) move along a chemically cross-linked myosin fibrous gel (1 cm long and 50 μm in diameter) with a velocity as high as that of native F-actin, by coupling to ATP hydrolysis. The motility observed in muscle protein-gels suggests that one might reconstruct a soft machine fueled by chemical energy by using actin and myosin molecules as elementary elements.