Effects of pH, detergent and salt on aggregation of Chinese-hamster-ovary-cell lysosomal enzymes.
Upon detergent or hypo-osmotic lysis of CHO-cell postnuclear supernatants or isolated lysosomes at pH 4.8, the lysosomal enzymes beta-hexosaminidase, beta-galactosidase, alpha-fucosidase and cathepsin C were readily pelleted, whereas the exogenous marker, long-term-internalized horseradish peroxidase, was not. Salt or pH elevation greatly decreased lysosomal-enzyme pelletability. The results suggest that, under native conditions, lysosomal hydrolases may be aggregated. Aggregation could promote enzyme retention within the organelle.
Buckmaster
M J
MJ
Department of Biochemistry and Nutrition, Virginia Polytechnic Institute and State University, Blacksburg 24061.
Ferris
A L
AL
Storrie
B
B
D000818:Animals; D020789:Cathepsin C; D002460:Cell Line; D002499:Centrifugation, Density Gradient; D006224:Cricetinae; D003412:Cricetulus; D003902:Detergents / Q000494:pharmacology; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000378:metabolism*; D005696:Galactosidases / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008247:Lysosomes / Q000187:drug effects / Q000201:enzymology*; D046911:Macromolecular Substances; D012965:Sodium Chloride / Q000494:pharmacology; D005644:alpha-L-Fucosidase / Q000378:metabolism*; D001616:beta-Galactosidase / Q000378:metabolism*; D001619:beta-N-Acetylhexosaminidases / Q000378:metabolism*
D003902:Detergents; D046911:Macromolecular Substances; D012965:Sodium Chloride; D005696:Galactosidases; D001616:beta-Galactosidase; D005644:alpha-L-Fucosidase; D001619:beta-N-Acetylhexosaminidases; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D020789:Cathepsin C