Skip to main content
Journal cover image

DNA breakage and closure by rat liver type 1 topoisomerase: separation of the half-reactions by using a single-stranded DNA substrate.

Publication ,  Journal Article
Been, MD; Champoux, JJ
Published in: Proc Natl Acad Sci U S A
May 1981

Circular single strands of bacteriophage phi X174 DNA are broken by rat liver DNA nicking-closing enzyme (type 1 topoisomerase) in low salt (50 mM KCl) at 37 degrees C, generating linear strands containing covalently bound enzyme [Been, M. D. & Champoux, J. J. (1980) Nucleic Acids Res. 8, 6129-6142]. The linear strands can be recircularized in the presence of 10 mM MgCl2 at 24 degrees C and 37 degrees C or 250 mM KCl at 24 degrees C. Recircularization is blocked when the hydroxyl group at the 5' terminus is phosphorylated. The linears generated by the nicking-closing enzyme can also be joined to other DNA fragments containing 5' hydroxyls, but not 5' phosphates. The linkage formed in both the intrastrand and interstrand reactions is stable to alkali. Reclosure of broken single strands is presumed to be analogous to the closure step that occurs durng nicking and closing cycles on duplex DNA.

Duke Scholars

Altmetric Attention Stats
Dimensions Citation Stats

Published In

Proc Natl Acad Sci U S A

DOI

ISSN

0027-8424

Publication Date

May 1981

Volume

78

Issue

5

Start / End Page

2883 / 2887

Location

United States

Related Subject Headings

  • Substrate Specificity
  • Rats
  • Liver
  • Kinetics
  • DNA, Viral
  • DNA, Single-Stranded
  • DNA Topoisomerases, Type I
  • DNA Helicases
  • Bacteriophage phi X 174
  • Animals
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Been, M. D., & Champoux, J. J. (1981). DNA breakage and closure by rat liver type 1 topoisomerase: separation of the half-reactions by using a single-stranded DNA substrate. Proc Natl Acad Sci U S A, 78(5), 2883–2887. https://doi.org/10.1073/pnas.78.5.2883
Been, M. D., and J. J. Champoux. “DNA breakage and closure by rat liver type 1 topoisomerase: separation of the half-reactions by using a single-stranded DNA substrate.Proc Natl Acad Sci U S A 78, no. 5 (May 1981): 2883–87. https://doi.org/10.1073/pnas.78.5.2883.
Been, M. D., and J. J. Champoux. “DNA breakage and closure by rat liver type 1 topoisomerase: separation of the half-reactions by using a single-stranded DNA substrate.Proc Natl Acad Sci U S A, vol. 78, no. 5, May 1981, pp. 2883–87. Pubmed, doi:10.1073/pnas.78.5.2883.
Journal cover image

Published In

Proc Natl Acad Sci U S A

DOI

ISSN

0027-8424

Publication Date

May 1981

Volume

78

Issue

5

Start / End Page

2883 / 2887

Location

United States

Related Subject Headings

  • Substrate Specificity
  • Rats
  • Liver
  • Kinetics
  • DNA, Viral
  • DNA, Single-Stranded
  • DNA Topoisomerases, Type I
  • DNA Helicases
  • Bacteriophage phi X 174
  • Animals