Effect of calcium ions on the irradiation induced inactivation of cellulase.

Abstract The activity of cellulase irradiated at various temperatures was examined as a function of irradiation dose. The effect of calcium ions in radiation inactivation of cellulase at irradiation temperature of 30°C was studied by using calcium sulfate. The calcium ions have a protective ability against radiation caused inactivation of cellulase by scavenging species such as OH(-) formed by irradiation of cellulase aqueous solution, in which the effective concentration range of the calcium ions was ∼ 10(-3) M. The calcium ions do not act for the heat inactivation of the enzyme and the enzyme hydrolysis of filter paper or chaff as an activator because the calcium ions do not associate with the enzyme to form a calcium ion-enzyme complex.