title: NAD-binding site of the C3-like ADP-ribosyltransferase from Clostridium limosum.
abstract: Treatment of the Rho-ADP-ribosylating C3-like transferase from Clostridium limosum by ultraviolet irradiation in the presence of [carbonyl-14C]NAD incorporated 1 mol of label/mol of exoenzyme. Concomitantly, the transferase and NAD glycohydrolase activity was impaired. A peptide containing the radiolabel was obtained by proteolysis with either staphylococcal protease V8 or trypsin. Their amino acid sequences were Ala/Asp-Gly-Tyr-Ile-Glu-Pro-Ile-Ser-Thr-Phe-Lys-Gly-Gln-Leu-X-Val-Leu-Le u-Pro- Arg and Gly-Gln-Leu-X-Val-Leu-Leu-Pro-Arg, respectively. These sequences correspond with regions Ala-160 through Arg-179 and Gly-171 through Arg-179, respectively, of the very similar Clostridium botulinum C3 transferase, with X being Glu in the unlabeled enzyme. This identifies the glutamic acid residue that corresponds to Glu-174 of C. botulinum C3 transferase as part of the NAD-binding site of the catalytic center of the C. limosum exoenzyme.
authors.affiliation: Institut für Pharmakologie und Toxikologie, Universität des Saarlandes, Homburg-Saar, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Jung
authors.forename: I
authors.initials: I
authors.lastname: Just
authors.forename: J
authors.initials: J
authors.lastname: van Damme
authors.forename: J
authors.initials: J
authors.lastname: Vandekerckhove
authors.forename: K
authors.initials: K
authors.lastname: Aktories
mesh_terms: D036002:ADP Ribose Transferases / Q000737:chemistry*; D000595:Amino Acid Sequence; D001427:Bacterial Toxins / Q000737:chemistry*; D001665:Binding Sites; D001905:Botulinum Toxins; D003013:Clostridium / Q000201:enzymology*; D005971:Glutamates / Q000737:chemistry; D008969:Molecular Sequence Data; D009243:NAD / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry
chemical_list: D001427:Bacterial Toxins; D005971:Glutamates; D010446:Peptide Fragments; D009243:NAD; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D001905:Botulinum Toxins