Thermodynamic aspects of ATP hydrolysis of actomyosin complex

Unraveling a Force-Generating Allosteric Pathway of Actomyosin Communication Associated with ADP and Pi Release

“…The molecular events that enable myosin to bind to actin in a post-hydrolysis state with bound ADP and P i are still a matter of debate [ 11 , 13 , 14 , 17 , 39 ]. The state is predicted to represent a high actin affinity conformation with the actin-binding cleft closed; however, it is different from the classical rigor state with the lever-arm in an up position [ 20 , 40 , 41 ].…”

P-type ATPases use a domain-association mechanism to couple ATP hydrolysis to conformational change

“…In particular, the P-A packing energy drives the P-ATPase to the transition state E 2 * P at which the energy-releasing step of dephosphorylation occurs. A similar reasoning of ''energy storage in dissociation'' has been proposed to explain the ATP hydrolysis cycle in linear ATP-driven motors such as the actomyosin system (Zhang and Feng 2016) as well as ABC transporters . In the words of P. Boyer who solved the mystery of rotatory ATP synthase, such a mechanism can be called ''binding change mechanism'' (Boyer 1998).…”

Exhaustion of Skeletal Muscle Fibers Within Seconds: Incorporating Phosphate Kinetics Into a Hill-Type Model

“…Resulting time courses of most involved reactants, including their length-dependency, are displayed in Figure A1 in Supplementary Material. The addressed interaction between ATP, ADP, and P i is known to influence the chemical potential (Zhang and Feng, 2016) or affinity (Allen and Orchard, 1987;Cooke, 2007;Hancock et al, 2005) of ATP, write µ ATP , which constitutes for the new state variable of phosphate dynamics. In a nutshell, the position of equilibrium (22) influences the amount of free Gibbs energy from ATP hydrolysis via…”

“…where G • ATP ≈ −30 kJ/mol (Allen and Orchard, 1987;Cooke, 2007;Guynn and Veech, 1973;Rosing and Slater, 1972;Zhang and Feng, 2016) denotes the standard free enthalpy, R = 8.31 • 10 −3 kJ/(mol•K) the ideal gas constant, T = 303 K a temperature of 30 • C, and c 0 = 1 M the standard concentration. The latter serves as a normalization factor.…”