title: Evidence that DNA polymerase-alpha of calf thymus contains a subunit of molecular weight 155000.
abstract: Small samples of the 8-S species of enzymes (A1 and A2) occurring in the DNA polymerase-alpha fraction of calf thymus, have been extensively purified using non-denaturing (normal) polyacrylamide gel electrophoresis. When peak fractions of activity on normal gels were subjected to dodecylsulphate-polyacrylamide gel electrophoresis, a polypeptide at 155000 correlated with polymerase activity. Samples of the 7.3-S (C) enzyme prepared from A2 by treatment with 2.4 M urea or isolated directly without exposure to urea, also showed the presence of a 155000-Mr polypeptide. It is concluded that the 7.3-S (C) enzyme, of previously estimated molecular weight 155000-170000, is a single polypeptide and that the 8-S enzymes A1 and A2 contain an additional subunit of 50000-70000 molecular weight.
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D004254:DNA Nucleotidyltransferases / Q000302:isolation & purification / Q000378:metabolism; D046911:Macromolecular Substances; D008970:Molecular Weight; D011485:Protein Binding; D013950:Thymus Gland / Q000201:enzymology*; D014508:Urea
chemical_list: D046911:Macromolecular Substances; D014508:Urea; D004254:DNA Nucleotidyltransferases