title: Characterization of two forms of poly(ADP-ribose) glycohydrolase in guinea pig liver.
abstract: A poly(ADP-ribose) glycohydrolase from guinea pig liver cytoplasm has been purified approximately 45,000-fold to apparent homogeneity. The cytoplasmic poly(ADP-ribose) glycohydrolase designated form II differed in several respects from the nuclear poly(ADP-ribose) glycohydrolase I (Mr = 75,500) previously purified from the same tissue (Tanuma et al., 1986a). The purified glycohydrolase II consists of a single polypeptide with Mr of 59,500 estimated by a sodium dodecyl sulfate-polyacrylamide gel. A native Mr of 57,000 was determined by gel permeation. Peptide analysis of partial proteolytic degradation of glycohydrolases II and I with Staphylococcus aureus V8 protease revealed that the two enzymes were structurally different. Amino acid analysis showed that glycohydrolase II had a relatively low proportion of basic amino acid residues as compared with glycohydrolase I. Glycohydrolase II and I were acidic proteins with isoelectric points of 6.2 and 6.6, respectively. The optimum pH for glycohydrolases II and I were around 7.4 and 7.0, respectively. The Km value for (ADP-ribose)n (average chain length n = 15) and the Vmax for glycohydrolase II were 4.8 microM and 18 mumol of ADP-ribose released from (ADP-ribose)n.min-1.(mg of protein)-1, respectively. The Km was about 2.5 times higher, and Vmax 2 times lower, than those observed with glycohydrolase I. Unlike glycohydrolase I, glycohydrolase II was inhibited by monovalent salts. ADP-ribose and cAMP inhibited glycohydrolase II more strongly than glycohydrolase I. These results suggest that eukaryotic cells contain two distinct forms of poly(ADP-ribose) glycohydrolase exhibiting differences in properties and subcellular localization.
authors.affiliation: Department of Life Science, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Maruta
authors.forename: K
authors.initials: K
authors.lastname: Inageda
authors.forename: T
authors.initials: T
authors.lastname: Aoki
authors.forename: H
authors.initials: H
authors.lastname: Nishina
authors.forename: S
authors.initials: S
authors.lastname: Tanuma
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D006026:Glycoside Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D006168:Guinea Pigs; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008970:Molecular Weight; D010449:Peptide Mapping; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D007527:Isoenzymes; D006026:Glycoside Hydrolases; C022407:poly ADP-ribose glycohydrolase