Purification and characterization of a human liver arylacetamide deacetylase.
Arylacetamide deacetylation is an important enzyme activity in the metabolic activation of arylamine substrates to ultimate carcinogens, best described as a carboxylesterase/amidase type of reaction. A 7-fold variation in the Vmax of 2-acetylaminofluorene deacetylation in 24 human livers was observed. An acetylaminofluorene deacetylase was purified 90 fold from human liver microsomes by PEG-fractionation, anion exchange and hydrophobic interaction chromatography. The purified 45kD protein showed no amino acid sequence homology to other carboxylesterases, neither in its N-terminus nor in tryptic peptides. Antibodies raised against the deacetylase recognized the protein with high specificity. This report thus describes the first arylacetamide deacetylase in human liver.
Probst
M R
MR
Department of Pharmacology, University of Basel, Switzerland.
Jenö
P
P
Meyer
U A
UA
D000581:Amidohydrolases / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D002265:Carboxylic Ester Hydrolases / Q000235:genetics; D006801:Humans; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008862:Microsomes, Liver / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000302:isolation & purification; D012689:Sequence Homology, Nucleic Acid; D012995:Solubility
D010446:Peptide Fragments; C569302:AADAC protein, human; D002265:Carboxylic Ester Hydrolases; D000581:Amidohydrolases; C043521:2-acetylaminofluorene N-deacetylase