Enhancing Yeast Transformation: Achieving up to a Tenfold Increase Through a Single Adjustment in the Lithium...

The Lithium-PEG method for transforming yeast cells is a standard procedure used in most yeast laboratories. After several optimizations, this method can yield up to 10⁶ transformants per µg of plasmid. Some applications, such as library screening or complex transformations, necessitate maximizing transformation yield. Here, we demonstrate that the addition of a sorbitol solution serves as an osmo-protectant during and after heat shock, resulting in up to a tenfold increase in transformation efficiency. This optimization requires only one additional pipetting step compared to the original protocol, making it practical for routine use.