[Effect of storage conditions on the kinetic properties of myosin ATPase].
"Substrate inhibition", which has been described earlier for myosin Ca-ATPase in low ionic strength KCl solution [1], is found to take place also at high KCl concentration and under partial modification of enzyme thiol groups with p-CMB. "Substrate inhibition" disappeared when increasing Ca2+ concentration up to 25-40 mM. These kinetic properties are characteristic for fresh isolated enzyme and myosin preparations stored in 0.5 M KCl. They may change under storage of enzyme preparations at higher KCl concentrations: no "substrate inhibition" is observed after 6-8-day storage of myosin preparations in 3 M KCl at the presence of 4-5 mM CaCl2. The data on optical rotation dispersion and analytical ultracentrifugation have shown that the storage of myosin in 3 M KCl is accompanied by structural changes of the protein.
D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors; D002122:Calcium Chloride; D007700:Kinetics; D009218:Myosins / Q000037:antagonists & inhibitors; D011189:Potassium Chloride
D011189:Potassium Chloride; D000251:Adenosine Triphosphatases; D009218:Myosins; D002122:Calcium Chloride
Vliianie usloviĭ khraneniia na kineticheskie svoĭstva miozinovoĭ ATPazy