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Analysis of topoisomerase function in bacterial replication fork movement: use of DNA microarrays.

ABSTRACT: We used DNA microarrays of the Escherichia coli genome to trace the progression of chromosomal replication forks in synchronized cells. We found that both DNA gyrase and topoisomerase IV (topo IV) promote replication fork progression. When both enzymes were inhibited, the replication fork stopped rapidly. The elongation rate with topo IV alone was 1/3 of normal. Genetic data confirmed and extended these results. Inactivation of gyrase alone caused a slow stop of replication. Topo IV activity was sufficient to prevent accumulation of (+) supercoils in plasmid DNA in vivo, suggesting that topo IV can promote replication by removing (+) supercoils in front of the chromosomal fork.

SUBMITTER: Khodursky AB

PROVIDER: S-EPMC16879 | biostudies-literature | 2000 Aug

REPOSITORIES: biostudies-literature

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Analysis of topoisomerase function in bacterial replication fork movement: use of DNA microarrays.

Khodursky A B AB Peter B J BJ Schmid M B MB DeRisi J J Botstein D D Brown P O PO Cozzarelli N R NR

Proceedings of the National Academy of Sciences of the United States of America 20000801 17

We used DNA microarrays of the Escherichia coli genome to trace the progression of chromosomal replication forks in synchronized cells. We found that both DNA gyrase and topoisomerase IV (topo IV) promote replication fork progression. When both enzymes were inhibited, the replication fork stopped rapidly. The elongation rate with topo IV alone was 1/3 of normal. Genetic data confirmed and extended these results. Inactivation of gyrase alone caused a slow stop of replication. Topo IV activity was ...[more]

PMID: 10944214

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Topoisomerase function in E. coli replication fork movement

Project description:Analysis of topoisomerase function in bacterial replication fork movement: use of DNA microarrays. We used DNA microarrays of the Escherichia coli genome to trace the progression of chromosomal replication forks in synchronized cells. We found that both DNA gyrase and topoisomerase IV (topo IV) promote replication fork progression. When both enzymes were inhibited, the replication fork stopped rapidly. The elongation rate with topo IV alone was 1/3 of normal. Genetic data confirmed and extended these results. Inactivation of gyrase alone caused a slow stop of replication. Topo IV activity was sufficient to prevent accumulation of (+) supercoils in plasmid DNA in vivo, suggesting that topo IV can promote replication by removing (+) supercoils in front of the chromosomal fork. This study is detailed in Khodursky AB et al.(2000) Proc Natl Acad Sci U S A 97:9419-24 Keywords: other

2001-07-30 | E-GEOD-8 | biostudies-arrayexpress

Topoisomerase function in E. coli replication fork movement

2001-07-30 | GSE8 | GEO

Anatomy and dynamics of DNA replication fork movement in yeast telomeric regions.

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Topoisomerase III Acts at the Replication Fork To Remove Precatenanes.

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RMI1 promotes DNA replication fork progression and recovery from replication fork stress.

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Breathing fluctuations in position-specific DNA base pairs are involved in regulating helicase movement into the replication fork.

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