title: Plasmid migration using orthogonal-field-alternation gel electrophoresis.
abstract: The migration properties of a series of supercoiled plasmids ranging in size from 4 to 16 kilobases (kb) have been analyzed by orthogonal-field-alternation gel electrophoresis (OFAGE). These circular DNAs enter the gel and are well resolved. Unlike linear DNA molecules, the relative mobilities of these plasmids are constant over a wide range of pulse times, from 10 to 120 seconds, as well as over a broad range of total running times, from 6 to 24 hours. Electrophoresis of supercoiled, relaxed, and nicked open circular forms as well as topoisomers of pBR322 shows that the extent of supercoiling has a dramatic effect on plasmid migration on OFAGE. Several practical applications for exploiting the different migration properties of circular and linear DNA molecules on OFAGE are presented.
authors.affiliation: Department of Biochemistry, University of California, San Francisco 94143.
authors.forename: R C
authors.initials: RC
authors.lastname: Hightower
authors.forename: D W
authors.initials: DW
authors.lastname: Metge
authors.forename: D V
authors.initials: DV
authors.lastname: Santi
mesh_terms: D002875:Chromosomes / Q000032:analysis; D004264:DNA Topoisomerases, Type I; D004278:DNA, Superhelical / Q000302:isolation & purification*; D004587:Electrophoresis, Agar Gel / Q000379:methods; D008970:Molecular Weight; D010957:Plasmids; D012441:Saccharomyces cerevisiae / Q000235:genetics
chemical_list: D004278:DNA, Superhelical; D004264:DNA Topoisomerases, Type I