FIG 4.

Stepwise evolution of pWBG753, pWBG715, and pWBG731. (A) Plasmid maps of sequenced plasmids pWBG753 and pWBG731 and map for the predicted sequence of pWBG715 (not to scale relative to each other). The outermost rings on each plasmid map indicate percent nucleotide identity to contigs from a BLASTN query of the de novo sequence assembly of WBG7565, which carries pWBG715b, against each plasmid sequence. The gray sectors indicate the pWBG753 backbone conserved on all three plasmids, the yellow region on pWBG753 represents the region replaced with the orange region on pWBG715, and the red sector indicates the pT181 region on pWBG715 that was replaced by the blue pWBG745-like conjugative plasmid on pWBG731. (B) Agarose electrophoresis of ClaI-digested pWBG731 (left) and pWBG715b (right) DNA. Fragment sizes for pWBG731 are indicated on the left, and recognizable corresponding fragments in the pWBG715 digest are indicated on the right.