title: An inhibitory effect of sulfhydryl compounds in the assay of rat and mouse thymic terminal deoxynucleotidyl transferase (TdT).
abstract: Terminal deoxynucleotidyl transferase (TdT) was assayed in 100,000 X g supernatants of homogenized thymus using 3H-dGTP and an oligo p(dA)12-18 primer. 2-Mercaptoethanol (2-ME) caused a depression of activity with rat and mouse thymus extracts but increased activity using bovine or lamb thymus extracts. Glutathione (GSH), L-cysteine and dithiothreitol (DTT) also showed an inhibitory effect with the rat thymus extract. Inhibition was significant at concentrations of sulfhydryl compounds commonly included in TdT assays (1 mM-2 mM).
mesh_terms: D000818:Animals; D004253:DNA Nucleotidylexotransferase / Q000032:analysis* / Q000037:antagonists & inhibitors; D004254:DNA Nucleotidyltransferases / Q000032:analysis*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D051381:Rats; D011919:Rats, Inbred Strains; D013438:Sulfhydryl Compounds / Q000494:pharmacology*; D013950:Thymus Gland / Q000201:enzymology*
chemical_list: D013438:Sulfhydryl Compounds; D004254:DNA Nucleotidyltransferases; D004253:DNA Nucleotidylexotransferase