Studies on the proteins of fish skeletal muscle. 3. Cod myosin and cod actin

Abstract

By modifying the extraction methods, proteins could be extracted from cod muscle resembling rabbit myosin and actin. Cod myosin resembles rabbit myosin in appearance, solubility behavior to adenosine triphosphate (ATP) and F-actin, electro-phoretic behavior, and instrinsic viscosity, but the sedimentation constant and diffusion constant were much closer to the values for actomyosin. These give the same axial ratio of 50 but a molecular weight at least double that of rabbit myosin. Cod F-actin is more easily extracted than rabbit due to the lack of stroma. It closely resembles rabbit actin in physical and chemical properties and gives a molecular weight of 160,000 from osmotic pressure, although ultra-centrifuge data indicate the molecular dimensions are uncertain. In 0.6 [image]- KI cod G-actin exists as a dimer.