Shuttle vector to facilitate construction of gene disruptions in E. coli. The gene of interest is cleaved at an appropriate site, made flush, and ligated to the SmaI fragment from this plasmid that contains kanR and the yeast selectable marker. (personal communication) The order of the major features in this plasmid is:kanR – URA3 – EcoRI/MCS/HindIII – f1 ori – ampR – pMB1 ori. (personal communication) The appropriate product is selected for by kanR in E.coli. (personal communication) Restriction digests of the clone give the following sizes (kb): EcoRI–6.4; PstI–4.7, 0.9, 0.8; HindIII–3.9, 1.4, 1.2; BglII–4.8, 1.5. (ATCC staff) Medium is 1227 LB plus ampicillin. Hosts: E.coli HB101, Saccharomyces cerevisiae, E.coli.