文摘
Saccharomyces boulardii is the best known probiotic yeast, widely used as a therapeutic agent for the treatment or prevention of diarrhea and intestine disorders. In the present work, we established a target gene disruption system for S. boulardii based on the Cre-loxP system used for S. cerevisiae and other fungi by screening out selection markers, working out the transformation method, and constructing essential plasmids for S. boulardii. The established system was successfully applied to the URA3 gene disruption and created an ura3 null mutant strain of S. boulardii. The system can be used for PCR mediated gene disruption, cloning mediated gene disruption, and reintroduction of the deleted gene back to the mutant. All the introduced exogenous DNAs in the gene disruption procedures were removed from the final mutant strain except the two 34 bp loxP pieces left in deleted gene loci.