Zonal rotor analysis of the subcellular localization of α-glycerophosphate dehydrogenase, α-naphthyl palmitate and β-naphthyl laurate hydrolases in the mucosa of the guinea-pig small intestine

Whele homogenate of guinea-pig small intestine mucosa was analysed by centrifugation in a zonal rotor. The results indicate that FAD-linked α-glycerophosphate dehydrogenase is localized in the mitochondria and that NAD-linked α-glycerophosphate dehydrogenase is a soluble phase enzyme. An enzyme hydrolysing α-naphthyl palmitate at an acid pH was localized in the lysosomes and was activated by 0.1% Triton X-roo and by freezing and thawing. An alkaline hydrolase acting on β-naphthyl laurate was localized in the 'microsomes'. The possibility of this enzyme being different from α-naphthyl acetate hydrolase is discussed.