An improved method for rapid purification of covalently closed circular plasmid DNA over a wide size range.
An improved method has been developed for the large-scale purification of covalently closed circular (CCC) plasmid DNA molecules of sizes ranging from 4.3 to 73 kb. This protocol uses an alkaline-lysis procedure followed by acid-phenol extraction but with several modifications to previously reported methods. The principal modification is the replacement of NaCl by MgCl2 in the extraction buffer to improve yield and to remove chromosomal and other non-CCC plasmid DNA. Plasmid DNA can be purified in less than 1 h and used successfully in restriction enzyme analysis and cloning experiments.
Department of Microbiology, University of Glasgow, UK.
A K
AK
Azad
J G
JG
Coote
R
R
Parton
D004269:DNA, Bacterial / Q000302:isolation & purification*; D004270:DNA, Circular / Q000302:isolation & purification*; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli; D015636:Magnesium Chloride; D010957:Plasmids / Q000235:genetics*; D012965:Sodium Chloride
D004269:DNA, Bacterial; D004270:DNA, Circular; D015636:Magnesium Chloride; D012965:Sodium Chloride