Duplication and Transformation of the Schizosaccharomyces pombe Collection of Deletion Strains.

We present an efficient and organized method of lithium acetate and polyethylene glycol-based transformation of plasmid DNA into the commercially available collection of Schizosaccharomyces pombe with single-gene deletions. We also describe how to prepare a duplicate collection of the deletion strains in order to preserve the longevity of the master set. These protocols are adapted to the 96-well format of the 3004 strains of the Version 2.0 Bioneer set but can also be used for later releases of the collection. This transformation method typically yields efficiencies in the range between 1.0 × 103 and 1.0 × 104 transformants per microgram of plasmid DNA. However, some deletion strains transformed with significantly lower efficiencies. We provide a list of these difficult-to-transform strains. Applications for this methodology include the transformation of the deletion set with plasmids necessary for genetic screens.