Purification and characterization of an ATPase from human liver which catalyzes ATP hydrolysis in the presence of the conjugates of bilirubin bile acids and glutathione.
An ATPase has been purified from the membrane fraction of human liver which catalyzes ATP in the presence of bilirubin ditaurate, lithocholic acid 3-O-sulfate and lithocholic acid 3-O-glucuronide as well as dinitrophenylglutathione and other glutathione conjugates. Its subunit Mr value (38,000) and immunological properties are similar to dinitrophenylglutathione ATPase of human erythrocytes. Kinetic constants of the enzyme for the conjugates of glutathione, bile acids and bilirubin are comparable indicating that this ATPase may mediate active transport of all these anionic conjugates in liver.
Awasthi
Y C
YC
Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77550.
Singhal
S S
SS
Gupta
S
S
Ahmad
H
H
Zimniak
P
P
Radominska
A
A
Lester
R
R
Sharma
R
R
D000251:Adenosine Triphosphatases / Q000302:isolation & purification / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D001647:Bile Acids and Salts / Q000378:metabolism*; D015153:Blotting, Western; D002462:Cell Membrane / Q000201:enzymology; D002846:Chromatography, Affinity; D005965:Glucuronates / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008970:Molecular Weight; D013379:Substrate Specificity
D001647:Bile Acids and Salts; D005965:Glucuronates; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; C068387:S-(dinitrophenyl)glutathione ATPase; D005978:Glutathione