DNA supercoiling in vivo

Biophys Chem. 1988 Feb;29(1-2):7-15. doi: 10.1016/0301-4622(88)87020-0.

Abstract

DNA topoisomerase mutants of Escherichia coli and Saccharomyces cerevisiae were used to study the topological state of intracellular DNA. In E. coli, it is shown that switching off the gene topA encoding DNA topoisomerase I leads to an increase in the degree of negative supercoiling of intracellular DNA and inhibition of the growth of the cells: a d(pCpG)16.d(pCpG)16 sequence on a plasmid is also shown to flip from a right-handed B-helical structure to a left-handed Z-helical structure in vivo when topA is switched off. In S. cerevisiae, the topological state of intracellular DNA is little affected by the cellular levels of the topoisomerases.

Publication types

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

MeSH terms

  • DNA Topoisomerases, Type I / metabolism
  • DNA Topoisomerases, Type II / metabolism
  • DNA, Bacterial
  • DNA, Fungal
  • DNA, Superhelical*
  • Escherichia coli / enzymology
  • Escherichia coli / genetics*
  • Mutation
  • Nucleic Acid Conformation*
  • Plasmids
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics*
  • Temperature

Substances

  • DNA, Bacterial
  • DNA, Fungal
  • DNA, Superhelical
  • DNA Topoisomerases, Type I
  • DNA Topoisomerases, Type II