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Are single-stranded circles intermediates in plasmid DNA replication?

H te Riele·B Michel·S D Ehrlich
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Abstract

Plasmid pC194 exists as circular double-stranded and single-stranded DNA in Bacillus subtilis and Staphylococcus aureus. We report here that the plasmid pHV33, composed of pBR322 and pC194, exists as double- and single-stranded DNA in Escherichia coli, provided that the replication functions of pC194 are intact. Single-stranded pHV33 DNA is converted to double-stranded DNA by complementary strand synthesis probably initiated at rriB, a primosome assembly site present on pBR322. The efficiency of complementary strand synthesis affects the double-stranded copy number, which suggests that single-stranded DNA is a plasmid replication intermediate.

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Bacillus subtilisColiphagesDNA ReplicationDNA Restriction EnzymesDNA, CircularDNA, Single-StrandedEscherichia coliMicroscopy, ElectronNucleic Acid HybridizationPlasmidsProtein BiosynthesisStaphylococcus aureusJournal ArticleResearch Support, Non-U.S. Gov't

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H te Riele, B Michel, S D Ehrlich. 1986. Are single-stranded circles intermediates in plasmid DNA replication?. https://doi.org/10.1002/j.1460-2075.1986.tb04257.x

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