FIG. 5.

Effects of substitutions of region I, II, or III for the other two regions of ars2004M on ARS activity. (A) Two of three regions required for the ARS activity of ars2004M were replaced with copies of the other region. Transformation efficiencies relative to the pARS2004M value after 3 days of incubation are presented. The fragments inserted in tandem orientation are shown by shaded boxes. (B) Effects of clustering of region I fragments on ARS activity. Transformation efficiencies with derivatives of ars2004M lacking regions II and III but carrying three tandem copies of the region I fragment either at three or two separate places or at a single location are presented. ARS activity was enhanced as the region I fragments were placed closer together.