title: Protection of mammalian cells from diphtheria toxin by exogenous nucleotides.
abstract: Exogenous nucleotides were found to protect mammalian cells from the lethal effects of diphtheria toxin. Protective potency of a given nucleotide was base specific and phosphate chain length dependent. Full expression of protective potency required an intact nucleotide, but the effect did not appear to be mediated by nucleotide-induced phosphorylation. Nucleotides antagonized the binding of diphtheria toxin to its cell surface receptor in a manner that correlated with the degree of protection. It was concluded that cellular protection from diphtheria toxin by nucleotides results from inhibition of toxin-receptor binding and that nucleotides therefore may serve as valuable research tools for future studies.
mesh_terms: D000227:Adenine Nucleotides / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D002460:Cell Line; D002478:Cells, Cultured / Q000187:drug effects*; D004166:Diphtheria Antitoxin; D004167:Diphtheria Toxin / Q000378:metabolism / Q000633:toxicity; D000882:Haplorhini; D007668:Kidney; D009711:Nucleotides / Q000494:pharmacology*; D011955:Receptors, Drug / Q000378:metabolism
chemical_list: D000227:Adenine Nucleotides; D004166:Diphtheria Antitoxin; D004167:Diphtheria Toxin; D009711:Nucleotides; D011955:Receptors, Drug; D000255:Adenosine Triphosphate