Abstract
In vitro effect of various heavy metals on activity of α-mannosidase, which has been regarded as a zinc-enzyme, was investigated after purifying the enzyme from the liver and epididymis of healthy mice.
Unexpectedly, cadmium enhanced the enzyme activity at the concentrations from 10-5 to 10-3M, and both zinc and EDTA reversed the enhancement of the enzyme activity by cadmium maximally at the same concentration as cadmium.
Zinc alone slightly activated the enzyme through the tested concentrations (10-6-10-4M), and copper showed the similar enhancement of the activity to that by cad-mium, though the degree of the enhancement was not so great as compared with cadmium.These findings indicate that zinc and cadmium oppose each other on the activity of α-mannosidase obtained from the liver and epididymis of mice, and that the enzyme might not have zinc as an essential component.
