Adenovirus DNA replication in vitro: purification of the terminal protein in a functional form

Proc Natl Acad Sci U S A. 1981 Nov;78(11):6779-83. doi: 10.1073/pnas.78.11.6779.


The 80,000-dalton form of the adenovirus (Ad) terminal protein (pTP) has been purified from Ad-infected HeLa cells. pTP was assayed by its ability to form a covalent complex with dCMP. The protein copurified with an activity that is essential for in vitro Ad DNA replication (Ad protein activity) as well as with a DNA polymerase activity that was distinguished from those of HeLa cell DNA polymerases alpha, beta, and gamma. The Ad protein-associated DNA polymerase activity was detected with activated DNA but not with poly(rA).oligo(dT) as template and was insensitive to aphidicolin and sensitive to N-ethylmaleimide. The Ad protein, DNA polymerase, and pTP-dCMP complex-forming activities sedimented in a glycerol gradient as a single peak with an apparent molecular size of 180,000 daltons. NaDodSO4/polyacrylamide gel analysis of the glycerol gradient fraction showed major bands of 80,000 and 140,000 daltons. The 80,000-dalton band was identified as pTP by comparison of its tryptic peptide map with that of the 55,000-dalton form of the terminal protein, which was purified from Ad virions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenoviruses, Human / enzymology*
  • DNA Replication*
  • DNA-Directed DNA Polymerase / metabolism*
  • HeLa Cells / enzymology
  • Humans
  • Molecular Weight
  • Viral Proteins / isolation & purification
  • Viral Proteins / metabolism*


  • Viral Proteins
  • DNA-Directed DNA Polymerase