Department of Biochemistry, Eastern Virginia Medical School, Norfolk, VA.
Distinction between supercoiled and linear DNA in transverse agarose pore gradient gel electrophoresis
Article first published online: 13 APR 2005
Copyright © 1992 VCH Verlagsgesellschaft mbH
Volume 13, Issue 1, pages 403–406, 1992
How to Cite
Wheeler, D., Lin, J.-H. and Chrambach, A. (1992), Distinction between supercoiled and linear DNA in transverse agarose pore gradient gel electrophoresis. ELECTROPHORESIS, 13: 403–406. doi: 10.1002/elps.1150130185
- Issue published online: 13 APR 2005
- Article first published online: 13 APR 2005
- Manuscript Received: 20 JAN 1992
Four species of linear DNA and the first four members of a linking series, generated by treatment of plasmid DNA (PUC19, 2.7 kb) with mitochondrial topoisomerase, were differentiated by transverse agarose pore gradient gel electrophoresis. The experimental curves of migration distance vs. agarose concentration (Ferguson curves) of supercoiled DNA exhibit a steeper trajectory than those of linear DNA of the same size range. As a consequence, the four supercoiled species exhibit an increase in apparent size (relative to linear DNA standards) with increasing agarose concentration. Both the crossing of the Ferguson curves with those of linear standards as well as the apparent size increase with agarose concentration can serve to detect supercoiled plasmid-sized DNA in mixtures with linear DNA.