Fig. 2.

Highly similar conjugative plasmid is present in S. Tm and commensal E. coli. (A) S. Tm and Ec⁸¹⁷⁸ share a nearly identical conjugative plasmid. Sequence comparison of p2 S. Tm (outer circle) and p2 Ec⁸¹⁷⁸ (inner circle); gene functions are color coded. (B) Phylogram showing relation of p2 to other R-64 and ColIb-P9-type conjugative plasmids (E. coli PEK104, S. Tm R64-1, S. Tm R64-2, S. Heidelberg pSL476, Shigella sonnei pColb-P9, S. Tm pNF1358, S. Kentucky CVM29188, E. coli SE11-1). The phylogram was generated using PHYLIB and the Clustal W multiple sequence alignment algorithm; branch length represents the relative nucleotide differences of each plasmid compared with the reference sequence p2. (C) p2 is detected by gel electrophoresis in 4 of 10 E. coli isolates collected from S. Tm-infected mice (from Fig. 1B).