Molecular Mechanism of Force Generation in Biological Systems

All life systems from bacteria to humans are able to convert chemical energy into mechanical work and produce directed movement. The elucidation of mechanisms of energy transduction by biological molecules would help in understanding the physical principles of life. Skeletal muscle is an example of an efficient, highly organized biological engine. Muscle contraction occurs as the result of relative sliding of two (thick and thin) filament systems composed mainly of two proteins – myosin and actin. The energy for contraction is derived from the small organic molecule ATP. However, the mechanism of the coupling of ATP hydrolysis with force production is still obscure. Our research is focused on the study of the interaction of myosin with actin and ATP by various physical and biochemical methods. The main findings of our work are: ATP induced unbending of myosin molecule; the binding of myosin to the actin filament occurrss in multiple steps and might be presented as a rolling of the myosin head along the actin filament. Ordered formation of acto-myosin interface might generate force and directed movement (see Figure). We study the dynamics of the actin-myosin interface by applying a variety of experimental and computational approaches.

alt Force Generation 

Schematic of myosin-actin interaction