title: Mutations affecting the structure of hypoxanthine: guanine phosphoribosyltransferase in cultured Chinese hamster cells.
abstract: 14 Clones resistant to 8-azaguanine, isolated from mutagenically treated cultured cells from Chinese hamsters, were tested for loss of enzymic and immunological activities of hypoxanthine: guanine phosphoribosyltransferase. Three of the clones had no enzymic activity but reacted strongly with antiserum prepared against the enzyme (CRM(+)), indicating the presence of a defective enzyme protein, probably caused by a mutation in its structural gene. The other 11 mutants had little or no enzymic or immunologic activity. Revertant clones with positive enzymic and crossreacting immunologic activities were derived from both classes of mutants. The antiserum has been used for rapid purification of the phosphoribosyltransferase from Chinese hamster cells by immunoadsorbant affinity chromatography.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D000937:Antigen-Antibody Reactions; D001375:Azaguanine; D002247:Carbon Isotopes; D002478:Cells, Cultured / Q000201:enzymology*; D002846:Chromatography, Affinity; D002999:Clone Cells; D006224:Cricetinae; D003429:Cross Reactions; D004351:Drug Resistance; D000939:Epitopes; D006041:Goats / Q000276:immunology; D006147:Guanine; D007042:Hypoxanthines / Q000378:metabolism; D007118:Immunoassay; D009154:Mutation; D010430:Pentosyltransferases / Q000032:analysis* / Q000378:metabolism; D010641:Phenotype; D011233:Precipitin Tests; D011817:Rabbits / Q000276:immunology
chemical_list: D002247:Carbon Isotopes; D000939:Epitopes; D007042:Hypoxanthines; D006147:Guanine; D010430:Pentosyltransferases; D001375:Azaguanine