title: Common structure of the catalytic sites of mammalian and bacterial toxin ADP-ribosyltransferases.
abstract: The amino acid sequences of several bacterial toxin ADP-ribosyltransferases, rabbit skeletal muscle transferases, and RT6.2, a rat T-cell NAD glycohydrolase, contain three separate regions of similarity, which can be aligned. Region I contains a critical histidine or arginine residue, region II, a group of closely spaced aromatic amino acids, and region III, an active-site glutamate which is at times seen as part of an acidic amino acid-rich sequence. In some of the bacterial ADP-ribosyltransferases, the nicotinamide moiety of NAD has been photo-crosslinked to this glutamate, consistent with its position in the active site. The similarities within these three regions, despite an absence of overall sequence similarity among the several transferases, are consistent with a common structure involved in NAD binding and ADP-ribose transfer.
authors.affiliation: Laboratory of Cellular Metabolism, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892.
authors.forename: I J
authors.initials: IJ
authors.lastname: Okazaki
authors.forename: J
authors.initials: J
authors.lastname: Moss
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001427:Bacterial Toxins / Q000737:chemistry*; D002384:Catalysis; D006801:Humans; D008969:Molecular Sequence Data; D011065:Poly(ADP-ribose) Polymerases / Q000737:chemistry*; D011817:Rabbits; D051381:Rats; D017386:Sequence Homology, Amino Acid
chemical_list: D001427:Bacterial Toxins; D011065:Poly(ADP-ribose) Polymerases