Characterisation of Zygosaccharomyces rouxii centromeres and construction of first Z. rouxii centromeric vectors.

Zygosaccharomyces rouxii is a hemiascomycetous yeast known for its high osmotolerance, the basis of which still remains unknown. By exploring the Génolevures I database, four Z. rouxii fragments homologous to Saccharomyces cerevisiae centromeres were identified. Two of them were subjected to further analysis. Their function as centromeres in Z. rouxii was proved, and they were localized to Z. rouxii chromosomes II and VII, respectively. The species-specificity of centromeres was observed; plasmids with a Z. rouxii centromere were not recognized as centromeric in S. cerevisiae, and a S. cerevisiae centromere did not function as a centromere in Z. rouxii. Constructed plasmids bearing Z. rouxii centromeres serve as the first specific centromeric plasmids, and thus contribute to the so-far limited set of genetic tools needed to study the Z. rouxii specific features.