title: Amino acid-specific ADP-ribosylation. Identification of an arginine-dependent ADP-ribosyltransferase in rat liver.
abstract: A partially purified protein preparation from rat liver catalyzed the ADP-ribosylation of low molecular weight guanidino compounds and proteins. Agmatine and arginine, previously shown to be effective acceptors for the guanidine-dependent erythrocyte ADP-ribosyltransferase, were used as acceptors by the rat liver enzyme; lysine, histidine, and serine were inactive. The product of the reaction between [adenine-U-14C]NAD and agmatine catalyzed by the rat liver enzyme co-chromatographed with [adenine-U-14C]ADP-ribose-agmatine which was synthesized by the erythrocyte transferase; in parallel assays, formation of this product was associated with stoichiometric release of [carbonyl-14C]nicotinamide from [carbonyl-14C]NAD. In the presence of histones or other proteins and [adenine-U-14C]NAD or [32P]NAD, the rat liver enzyme catalyzed the formation of a radioactive product which was precipitable by trichloroacetic acid. Digestion of the [adenine-U-14C]-labeled precipitate with snake venom phosphodiesterase released a labeled compound identified as 5'-AMP. These data are consistent with the conclusion that a mono-(ADP-ribosyltransferase) is present in rat liver which utilizes guanidino compounds such as arginine as ADP-ribose acceptors. The ADP-ribose-glutamate bond has been shown to exist in rat liver. Since the catalytic sites of each transferase can accommodate and thus ADP-ribosylate only one specific amino acid, a family of site-specific transferases must be present. The availability of multiple site-specific transferases permits the cell to exert further control over ADP-ribosylation.
mesh_terms: D036002:ADP Ribose Transferases; D000246:Adenosine Diphosphate Ribose; D000818:Animals; D001120:Arginine; D002250:Carbon Radioisotopes; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D009713:Nucleotidyltransferases / Q000378:metabolism*; D010761:Phosphorus Radioisotopes; D011065:Poly(ADP-ribose) Polymerases; D051381:Rats; D013379:Substrate Specificity
chemical_list: D002250:Carbon Radioisotopes; D010761:Phosphorus Radioisotopes; D000246:Adenosine Diphosphate Ribose; D001120:Arginine; D036002:ADP Ribose Transferases; D011065:Poly(ADP-ribose) Polymerases; D009713:Nucleotidyltransferases