Aluminum inhibits the lysosomal proton pump from rat liver

Lysosomes are cytoplasmatic organelles, delimitated by a single lipoprotein membrane, that contain several enzymes mostly belonging to the hydrolases in that they function mainly for intracellular digestion. Lysosomal interna l pH is characteristically acidic and it is maintained around pH 4.5 by a p roton pump, an ATPase, that uses energy from ATP hydrolysis to translocate H+ ions into lysosomes. In the presence of Al3+ the proton pump activity is markedly reduced compromising acidic vesicles functionality. Among differe nt species utilized, Al-2(SO4)(3) and AIF(3) were the most effective. Alumi num effect was not observed when the Delta pH was produced artificially by nigericin.