Some combinations of marker swap plasmids and target locus may result in relatively high reversion rates. In most but not all cases the frequencies of successful convertants are greater than 30%.
A set of marker swap vectors, containing gene disruptions for standard markers such as his3::LEU2, useful in changing markers in the S. cerevisiae host chromosome or on plasmids.
The set allows interconversion among all six of the common markers HIS3, LEU2, TRP1, URA3, ADE2, and LYS2.
To convert the host phenotype from the existing yeast auxotrophic marker to a new marker (eg. HIS3 --> LEU2), transform with the restriction enzyme digested vector (eg. ApaI+PstI digested pHL3) and select for the appropriate phenotype (for pHL3, Leu+).
When swapping markers on an episomal plasmid, appropriate phenotype may result from loss of the plasmid unless a second selectable or scorable marker is used to ensure plasmid maintenance.