Studies on the Latency of Rat Liver Fumarate Hydratase1

Abstract

A hypotonic medium and nonionic detergents Triton X-100 and digitonin have no influence on the activity of fumarase in the homogenate or in the mitochondrial fraction either. Ionic detergents of deoxycholate, cholate and sodium dodecyl sulphate exert an inhibiting influence. The activity of enzyme was determined in an L-malate-fumarate system. 1 h of incubation and the original Racker’s method gave similar results. The lack of ‘latency’, found for the mitochondrial fumarase, was discussed basing on the data concerned with the penetration of metabolites through the inner mitochondrial membrane.

Activity and androgenic control of enzymes associated with the tricarboxylic acid cycle, lipid oxidation and mitochondrial shuttles in the epididymis and epididymal spermatozoa of the rat

“…Tissue homogenized in some media was as a routine sonicated, although the effectiveness of this treatment for releasing additional activity was not tested, except with 3-hydroxybutyrate dehydrogenase. However, for those enzymes extracted in medium (a) or (b) ( Ut:0 (Szkudlarek & Turski, 1975), was not observed in the present study. This could possibly be because a lower concentration of deoxycholate was used and bovine serum albumin was added.…”