PMID:2676991

From EcoliWiki
Jump to navigation Jump to search
Citation

Bakker, A and Smith, DW (1989) Methylation of GATC sites is required for precise timing between rounds of DNA replication in Escherichia coli. J. Bacteriol. 171:5738-42

Abstract

We have used the Koppes and Nordstrøm (Cell 44:117-124, 1986) CsCl density transfer approach for analysis of DNA from exponentially growing, isogenic Escherichia coli dam+ and dam mutant cells to show that timing between DNA replication initiation events is precise in the dam+ cells but is essentially random in the dam cells. Thus, methylation of one or more GATC sites, such as those found in unusual abundance within the origin, oriC, is required for precise timing between rounds of DNA replication, and precise timing between initiation events is not required for cell viability. Both the dam-3 point mutant and the delta(dam)100 complete deletion mutant were examined. The results were independent of the mismatch repair system; E. coli mutH cells showed precise timing, whereas timing in the isogenic E. coli mutH delta(dam)100 double mutant was random. The mechanism is thus different from the role of Dam methylation in mismatch repair and probably involves conversion of hemimethylated GATC sites present in daughter origins just after initiation to a fully methylated state.

Links

PubMed PMC210423

Keywords

DNA Replication; DNA, Bacterial/genetics; Escherichia coli/genetics; Escherichia coli Proteins; Methylation; Methyltransferases/physiology; Regulatory Sequences, Nucleic Acid; Site-Specific DNA-Methyltransferase (Adenine-Specific)

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

<annotationlinks/>

EcoliWiki Links

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

References

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