Gaucher disease: isolation and comparison of normal and mutant glucocerebrosidase from human spleen tissue.

Abstract

Glucocerebrosidase was purified 26,000-fold from spleens from normal humans and from patients with Gaucher disease (Gaucher spleens). The specific activities of the purified normal and mutant enzymes with glucocerebroside as substrate were 8.5 .times. 105 and 5.4 .times. 104 nmol/mg of protein per h, respectively. The ratio of enzymatic activities was constant throughout the isolation procedure. The 2 enzymes appeared to be similar by other parameters, e.g., substrate affinity, heat lability and pH optimum. Immunotitration with glucocerebrosidase antiserum showed equivalent quantities of crossreacting material in extracts of normal and Gaucher spleens. The genetic basis of Gaucher disease is apparently a structural mutation of glucocerebrosidase. The results of sodium dodecyl sulfate gel electrophoresis indicate that there are differences between the normal and the Gaucher disease enzyme.