Properties of Yeast Transformation

The ability to introduce DNA molecules into living cells by transformation has played a key role in the development of molecular cloning techniques in bacteria and, thus, in our understanding of gene structure and the control of gene expression. We have used yeast genes cloned on hybrid bacterial plasmids to develop a transformation system for Saccharomyces cerevisiae (Hinnen et al. 1978). Plasmids such as pYeleu10, an Escherichia coli yeast hybrid containing the LEU2+ gene from yeast inserted into the bacterial plasmid ColE1 (Ratzkin and Carbon 1977) provided a highly enriched source of individual yeast genes and enabled us to verify the transformation event at the molecular level by the identification of the ColE1 sequences in the transform ants.