Find in Library

The <i>Pseudomonas</i> genus includes many species living in diverse environments and hosts. It is important to understand which are the major evolutionary groups and what are the genomic/proteomic components they have in common or are unique. Towards this goal, we analyzed 494 complete <i>Pseudomonas</i> proteomes and identified 297 core-orthologues. The subsequent phylogenomic analysis revealed two well-defined species (<i>Pseudomonas aeruginosa</i> and <i>Pseudomonas chlororaphis</i>) and four wider phylogenetic groups (<i>Pseudomonas fluorescens</i>, <i>Pseudomonas stutzeri</i>, <i>Pseudomonas syringae</i>, <i>Pseudomonas putida</i>) with a sufficient number of proteomes. As expected, the genus-level core proteome was highly enriched for proteins involved in metabolism, translation, and transcription. In addition, between 39–70% of the core proteins in each group had a significant presence in each of all the other groups. Group-specific core proteins were also identified, with <i>P. aeruginosa</i> having the highest number of these and <i>P. fluorescens</i> having none. We identified several <i>P. aeruginosa</i>-specific core proteins (such as <i>CntL</i>, <i>CntM</i>, <i>PlcB</i>, <i>Acp1</i>, <i>MucE</i>, <i>SrfA</i>, <i>Tse1</i>, <i>Tsi2</i>, <i>Tse3</i>, and <i>EsrC</i>) that are known to play an important role in its pathogenicity. Finally, a holin family bacteriocin and a mitomycin-like biosynthetic protein were found to be core-specific for <i>P. cholororaphis</i> and we hypothesize that these proteins may confer a competitive advantage against other root-colonizers.