DNA supercoiling in vivo.

G N Giaever; L Snyder; J C Wang

doi:10.1016/0301-4622(88)87020-0

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DNA supercoiling in vivo.

G N Giaever·L Snyder·J C Wang

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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.

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DNA Topoisomerases, Type I DNA Topoisomerases, Type II DNA, Bacterial DNA, Fungal DNA, Superhelical Escherichia coli Mutation Nucleic Acid Conformation Plasmids Saccharomyces cerevisiae Temperature Journal Article 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

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G N Giaever, L Snyder, J C Wang. 1988. DNA supercoiling in vivo.. https://doi.org/10.1016/0301-4622(88)87020-0

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