The pQBR mercury resistance plasmids: a model set of sympatric environmental mobile genetic elements
Plasmids are important vectors of horizontal gene transfer, but most of our understanding of plasmid sequences comes from plasmids that have already adapted or co-adapted with their host genomes. Here we present sequences from a set of environmental mercury resistance plasmids captured exogenously into Pseudomonas from pristine agricultural soil. These plasmids constitute a model system for understanding the biology of naturally-occurring environmental plasmids capable of transferring into Pseudomonas.