PMID:776979

From EcoliWiki
Jump to: navigation, search
Citation

Uyemura, D, Eichler, DC and Lehman, IR (1976) Biochemical characterization of mutant forms of DNA polymerase I from Escherichia coli. II. The polAex1 mutation. J. Biol. Chem. 251:4085-9

Abstract

DNA polymerase I has been purified to homogeneity from an Escherichia coli K12 strain bearing the temperature-sensitive conditionally lethal mutation, polAex1. The purified enzyme shows no defect in its polymerase or 3' leads to 5'-exonuclease activities; however, its 5' leads to 3'-exonuclease activity is abnormally low at both 30 degrees and 43 degrees. Although the mutant enzyme is able to catalyze the coordinated 5' leads to 3' polymerization and 5' leads to 3' exonucleolytic hydrolysis of nucleotides at a nick in duplex DNA ("nick translation") at a measurable rate at 30 degrees, this reaction is undetectable at 43 degrees. This defect is very likely responsible for the retarded joining of nascent DNA fragments and the consequent loss of viability that occur in the mutant at this temperature.

Links

PubMed

Keywords

DNA Nucleotidyltransferases/metabolism; Escherichia coli/metabolism; Exonucleases/metabolism; Genetic Variation; Kinetics; Mutation; Temperature

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<protect><annotationlinks/></protect>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

See also

References

See Help:References for how to manage references in EcoliWiki.