ABSTRACT
The activities of animals are largely supported by muscle contraction. The most abundant protein in muscle is myosin, which behaves as a molecular motor. Therefore, myosin had long been considered to be a protein specific to muscle, but later it was established that myosins are also involved in other biological ac tivities (such as cytokinesis and organelle motility). The molecular shape of myosins differ with respect to function (1,2). Therefore, myosins form a broad family of proteins, and those found in muscle are classified as myosin II (con ventional myosin), myosin II is characterized by two head portions and a long tail (3,4) as described later (Sec. II.C). From the viewpoint of food, the edible part of myosystems is mostly the myofibrillar protein and predominantly myosin.