A gene‐cloning system for Kluyveromyces lactis and isolation of a chromosomal gene required for killer toxin production

Abstract
A transformation system derived from the circular plasmid pKD1 has been developed for Kluyveromyces lactis. The principle is essentially equivalent to that of the 2 μ/Saccharomyces cerevisiae transformation system. The main features of the system are presented. Using a pKD1‐based DNA bank of K. lactis, the KEX1 gene involved in the killer system was isolated by complementation.