Restriction digests of the clone give the following sizes (kb): EcoRI-- 4.2, 2.9; BamHI-- 7.0; SalI-- 7.0. Selection for TRP1 expression produces a plasmid copy number of 20-40; growth on YC minus leucine produces a copy number of 100-200. Similarly, the NruI, BamHI, SalI and SphI are adjacent and can be used for directional cloning. The vector was constructed by Kurt Runge. One of 9 YE-type shuttle vectors (ATCC 87541, 87554, 87560 an d 87640 - 87645) that have the leu2-d gene, which is correlated with high copy number in S. cerevisiae, when grown in medium lacking leucine. |