Association of phiX174 DNA-dependent ATPase activity with an Escherichia coli protein, replication factor Y, required for in vitro synthesis of phiX174 DNA

Proc Natl Acad Sci U S A. 1975 Sep;72(9):3342-6. doi: 10.1073/pnas.72.9.3342.


phiX174 DNA-dependent DNA synthesis is catalyzed in vitro by the combination of at least 11 purified protein fractions: dnaB, dnaC(D), and dnaG gene products, DNA polymerase III, DNA elongation factors I and II, DNA binding protein, and replication factors W, X, Y, and Z. The reaction requires ATP, 4 dNTPs, and Mg+2 and is specific for phiX174 (or phiXahb) DNA. Purified replication factor Y contains phiX174 (or phiXahb) DNA-dependent ATPase (or dATPase) activity. The ATPase activity is poorly stimulated by other single-stranded DNA, by double-stranded DNA, or by RNA. The products of the phiX174 DNA-dependent ATPase activity of factor Y are Pi and ADP (or dADP). The association of phiX174 DNA-dependent ATPase activity with factor Y was shown in the following ways: (a) the two activities copurified with a constant ratio; (b) they comigrated on native polyacrylamide gel electrophoresis; (c) both activities were heat-inactivated at the same rate; and (d) both showed identical patterns of N-ethylmaleimide sensitivity.

Publication types

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

MeSH terms

  • Adenosine Triphosphatases / analysis
  • Adenosine Triphosphatases / antagonists & inhibitors
  • Adenosine Triphosphatases / metabolism*
  • Cell-Free System
  • Coliphages / metabolism*
  • DNA Replication*
  • DNA, Viral / biosynthesis*
  • DNA, Viral / pharmacology
  • Enzyme Activation
  • Escherichia coli / enzymology*
  • Ethylmaleimide / pharmacology
  • Hot Temperature


  • DNA, Viral
  • Adenosine Triphosphatases
  • Ethylmaleimide