Identity of a cytosolic neutral cholesterol esterase in rat liver with the bile salt stimulated cholesterol esterase in pancreas.
A neutral cholesterol esterase has been purified to homogeneity from the cytosolic fraction of rat liver. The 105,000 x g supernatant fraction of rat liver was applied to a DEAE-cellulose column to isolate a partially purified fraction of hepatic cholesterol esterase. Immunoblot analysis of the partially purified liver fraction with the anti-porcine pancreatic cholesterol esterase IgG demonstrated a single band with a molecular weight of 67,000. The hepatic protein was then isolated by immunoaffinity chromatography technique using a column constructed with antibodies prepared against the pancreatic cholesterol esterase. Characterization of the hepatic cholesterol esterase revealed that the hepatic enzyme shared antigenic epitopes with the pancreatic cholesterol esterase and was similarly activated by addition of bile salt such as taurocholate. Moreover, amino-terminal sequencing analysis of the hepatic cholesterol esterase showed an identical sequence with the pancreatic enzyme. Taken together, these results showed that the cholesterol esterases in the liver and the pancreas are very similar and possibly identical proteins.
Department of Pathology and Laboratory Medicine, University of Cincinnati, College of Medicine, OH 45267 0529.
E D
ED
Camulli
M J
MJ
Linke
H L
HL
Brockman
D Y
DY
Hui
D000595:Amino Acid Sequence; D000818:Animals; D001647:Bile Acids and Salts / Q000502:physiology; D002265:Carboxylic Ester Hydrolases / Q000302:isolation & purification*; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D003600:Cytosol / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D008099:Liver / Q000201:enzymology*; D008297:Male; D008969:Molecular Sequence Data; D010179:Pancreas / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D002787:Sterol Esterase / Q000032:analysis / Q000302:isolation & purification*
D001647:Bile Acids and Salts; D002265:Carboxylic Ester Hydrolases; D002787:Sterol Esterase