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. 1977 Apr;130(1):148–153. doi: 10.1128/jb.130.1.148-153.1977

Method for obtaining more-accurate covalently closed circular plasmid-to-chromosome ratios from bacterial lysates by dye-buoyant density centrifugation.

D D Womble, D P Taylor, R H Rownd
PMCID: PMC235186  PMID: 323223

Abstract

A method that gives high recovery of deoxyribonucleic acid (DNA) from crude bacterial lysates using ethidium bromide-cesium chloride density gradient centrifugation is presented. After Pronase digestion and shearing of the lysate, essentially 100% recovery of chromosomal DNA and a reproducible recovery of covalently closed circular (CCC) plasmid DNA is obtained for a specific plasmid in a given strain. This method should be useful for comparing the CCC plasmid/chromosome ratio of various plasmid-host combinations.

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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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