Some effects of pressure treatment on actomyosin systems.
Natural actomyosin, actin and myosin, have been pressurized at up to 150 MN/m2 for 1 h at 0 degrees C and examined 3-5 h later. Pressurization of myosin resulted in the formation of aggregates with a molecular weight approximately that expected for a dimer, whereas with F-actin depolymerization occurred. With actomyosin, a gel to sol transition was promoted. Viscosity and light-scattering measurements indicated that pressurization results in a large measure of disaggregation of actomyosin in solution. Pressurization of actomyosin resulted in a greater decrease in the calcium-sensitive, than in the calcium-independent, Mg2+ ATPase activity. The Ca2+ and K+-EDTA ATPase activities of myosin were inhibited to about the same extent.
D000199:Actins; D000205:Actomyosin; D000251:Adenosine Triphosphatases / Q000032:analysis; D000818:Animals; D003102:Colloids; D005782:Gels; D006874:Hydrostatic Pressure; D008027:Light; D008970:Molecular Weight; D009218:Myosins; D011312:Pressure; D012542:Scattering, Radiation; D012756:Sheep; D014783:Viscosity
D000199:Actins; D003102:Colloids; D005782:Gels; D000205:Actomyosin; D000251:Adenosine Triphosphatases; D009218:Myosins