Southern blot analysis of DNA treated with Topoisomerase IV.

The filter contains pooled CsCl fractions of K. veneficum DNA, undigested (−), treated with Topoisomerase IV (To), and digested with EcoRI (E). The hybridization probe is identical to probe 4 of Figure 3, containing the highly conserved motif 2 and a partial sequence of motif 1. The location of the plastid genome is indicated by green shade above the lanes.