Ancient lateral gene transfer in the evolution of Bdellovibrio bacteriovorus

The recently sequenced genome of the predatory δ-proteobacterium Bdellovibrio bacteriovorus provides many insights into its metabolism and evolution. Because its genes are reasonably uniform in G+C content, it was suggested that B. bacteriovorus actively resists recombination with foreign DNA and horizontal transfer of DNA from other bacteria. To investigate this further, we carried out a variety of phylogenetic and comparative genomics analyses using data from >200 microbial genomes, including several published δ-proteobacteria. Although there might be little evidence for the extensive recent transfer of genes, we demonstrate that ancient lateral gene acquisition has shaped the B. bacteriovorus genome to a great extent.