Heterologous expression of the Kluyveromyces marxianus endopolygalacturonase gene (EPG1) using versatile autonomously replicating vector for a wide range of host

A versatile plasmid shuttle vector system pKDU7 was constructed, which is u seful for the heterologous gene expression in a wide range of Kluyveromyces and Saccharomyces strains. This cloning vector was constructed using the 1 .6-mu m circular plasmid pKD1 of Kluyveromyces drosophilarum, the URA3 gene of K. marxianus as well as the pUC19 sequences. The stability of vector in transformants strongly depends on the integrity of the functionally import ant elements of pKD1. It was shown by comparison of three recombinant vecto rs, which possessed the pKD1 sequence inserted in different ways. The effic ient transformation and stability maintenance of the vector constructed in various strains of Kluyveromyces and Saccharomyces was shown by the express ion of the EPG1 gene of the Kluyveromyces marxianus encoding pectin-degradi ng endopolygalacturonase. (C) 2000 Elsevier Science Inc. All rights reserve d.