The effect of adenosine diphosphate on the interaction of actin-myosin-adenosine triphosphate.

Abstract

It was shown in experiments made on natural actomyosin of rabbit skeletal muscle that ADP possesses direct and indirect effects on superprecipitation. The presence of ADP increases the turbidity of the actomyosin suspension. An optimal ATP/ADP ratio may help the development and existence of a PC conformer of actomyosin corresponding to a myosin-ADP-actin-myosin-ATP complex. In this complex the extent of actin-activation is controlled by the cooperativity between the two myosin heads which, on the other side, may regulate in vivo the optimal transformation of the chemical energy of ATP for mechanical work.