Figure 2

β-Galactosidase activity driven by various promoters in the S. cerevisiae S288C-derived strain EPY210C growing on galactose. EPY210C [31] was used as a base for strain construction to test promoter expression strength using promoter:lacZ constructs on integrative plasmids. Plasmids pSF015 (HXT7 promoter), pSF016 (PGK1 promoter), and pSF019 (TEF1 promoter), bearing promoters amplified from S. cerevisiae CEN.PK, have been described previously [22]. We reconstructed a P _GAL10 : lacZ fusion construct (pGAL10lac) by amplifying the relevant region from S. cerevisiae S288C genomic DNA (see Methods). The negative control was the promoterless lacZ plasmid pSF011 [22]. β-Galactosidase assays are described in the Methods. Bars are means of n = 3 biological replications; errors are standard deviations.