title: Selection and characterization of cells resistant to diphtheria toxin and pseudomonas exotoxin A: presumptive translational mutants.
abstract: Two classes of diphtheria toxin-resistant variants were selected from Chinese hamster ovary (CHO-K1) cells: permeability variants, in which uptake of toxin was impaired, and a new class of cytoplasmic variants, which were cross-resistant to Pseudomonas exotoxin. EF-2 prepared from the cytoplasmic variants was resistant to ADP-ribosylation by either toxin. The evidence presented suggests that these are translational variants possessing a mutationally altered EF-2 gene product. These studies also confirmed that Pseudomonas toxin ADP-ribosylates EF-2 in toxin-sensitive intact cells, as well as in cell-free systems.
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000818:Animals; D001427:Bacterial Toxins / Q000494:pharmacology*; D002460:Cell Line; D002463:Cell Membrane Permeability / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects* / Q000378:metabolism; D006224:Cricetinae; D003637:DEAE-Dextran / Q000494:pharmacology; D004167:Diphtheria Toxin / Q000494:pharmacology*; D004351:Drug Resistance; D005796:Genes; D014644:Genetic Variation; D009154:Mutation; D014176:Protein Biosynthesis; D011550:Pseudomonas aeruginosa
chemical_list: D001427:Bacterial Toxins; D004167:Diphtheria Toxin; D000244:Adenosine Diphosphate; D003637:DEAE-Dextran