Abstract
Alaska pollack myosin B (MB) was dissolved in 40mM Tris-maleate (pH 7.0) containing varied concentrations (0.3-2.0M) of NaCl and stored at 10°C, to examine for physico-chemical and bio-chemical changes. At 1.0M or higher concentrations of NaCl, MB showed a marked decrease in viscosity and ATP-sensitivity, a decrease in Mg-, and EDTA-ATPase activities. These changes were accompanied by a concomitant appearance of myosin in ultracentrifugal and gel filtration patterns. Occurrence of 50mM KCl-soluble actin was also observed. The soluble actin did not activate Mg-ATPase activity nor inhibit EDTA-ATPase activity of intact myosin. On the other hand, MB quickly lost Ca-ATPase activity when treated with NaCl more than 1.0M.
These results indicated that most of Alaska pollack MB was dissociated into myosin and actin, and both components were denatured at higher concentration of NaCl.
