Restriction digests of the clone give the following sizes (kb): XhoI--8.5; HindIII--5.5, 1.9, 1.1; EcoRI--7.1, 1.4. REP3X (ATCC 87603) and REP4X (ATCC 87604) differ in that REP3X contains LEU2 (2.2 kb) and REP4X contains ura4+ (1.8 kb). REP3X (ATCC 87603) and REP4X (ATCC 87604) contain full strength nmt1 promoter whereas REP41X (ATCC 87605) and REP42X (ATCC 87607) with medium strength (nmt1*) and REP81X (ATCC 87606) and REP82X (ATCC 87608) with low strength (nmt1**) due to mutation in the TATA box by Basi et al. (Gene 123:131-136, 1993). REP4X was constructed by deleting the ATG in the polylinker of the original REP4 plasmid. An XhoI linker was cloned into the blunted BalI-SalI cut REP4 plasmid. The SalI site is preserved. |