Electroporation of Pichia pastoris

Abstract

The introduction of foreign DNA into the yeast Pichia pastoris is similar to the processes used with Saccharomyces cerevisiae and routinely performed by the electroporation of plasmid DNA into electro-competent (E-comp) P. pastoris cells (Becker and Guarente, Methods Enzymol 194:182–187, 1991). Transformation of spheroplasts is more difficult (Cregg et al., Mol Cell Biol 5:3376–3385, 1985), and current methods to make chemically competent P. pastoris cells results in significantly fewer transformants (Pichia protocols, 2nd edn, Totowa, 27–42). Following are protocols to prepare E-comp P. pastoris cells, and to electroporate plasmid DNA into these cells to generate transformed cells.