ISOLATION OF ULTRAPURE SUPERCOILED PLASMID-DNA USING PREPARATIVE ELECTROPHORESIS

A large-scale preparative polyacrylamide gel electrophoresis (PAGE) sy stem for the isolation of high-purity supercoiled plasmid-DNA is descr ibed. This method should prove suitable for the isolation of large DNA molecules, either plasmid or linear DNA, that is required for the pro duction of transgenic animals, for instance. The efficiency of the met hod is illustrated by the isolation of the gene for the green fluoresc ent protein, cloned into a mammalian expression vector and used for tr ansfection of eukaryotic cells.