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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1974 Oct;71(10):3858–3862. doi: 10.1073/pnas.71.10.3858

Properties of the Escherichia coli DNA Binding (Unwinding) Protein: Interaction with DNA Polymerase and DNA

Ian J Molineux 1, Malcolm L Gefter 1
PMCID: PMC434283  PMID: 4610564

Abstract

The E. coli DNA binding protein reduces the activity of the single-strand-specific nucleases associated with all three DNA polymerases known in E. coli. A slight excess of binding protein over that required to saturate the DNA template leads to total inhibition of activity of the 3′ → 5′ nucleases associated with DNA polymerases I and III, but restores maximum activity of the DNA polymerase II-associated nuclease. The binding protein forms a specific complex with DNA polymerase II in the absence of DNA, and it is this complex that degrades a DNA·binding protein complex. Binding protein also facilitates the binding of DNA polymerase II to single-stranded DNA, whereas the binding to DNA of DNA polymerase I is inhibited. These data may explain the specificity with which the binding protein enhances the synthetic ability of DNA polymerase II.

Keywords: single-strand-specific nuclease, protein·protein and DNA·protein interactions

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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