pYES3/CT and pYES6/CT are S. cerevisiae expression vectors derived from the parental pYES2 vector. Vectors feature a C-terminal V5 epitope for detection with an Anti-V5 Antibody. pYES3/CT carries the TRP1 selection marker for selection in yeast. pYES6/CT carries the bsd resistance gene for selection with the antibiotic Blasticidin, a potent selection agent that can be used at very low concentrations and in any strain regardless of auxotrophic marker.