One of 9 shuttle vectors (ATCC 87585 87593) allowing lacZ detection of cloned inserts and containing the pUC19 MCS with all 10 cloning sites unique. Vectors differ in mode of replication (YE, YC or YI­type) and yeast marker (LEU2, URA3 or TRP1). This is a YE­type (yeast episomal) vector with the URA3 marker. The PstI restriction site from the URA3 gene of S. cerevisiae was removed by using oligo­directed mutatgenesis.