Maximum-likelihood tree and prevalence of duplicated, singleton, and orphan genes within 45 complete α-proteobacterial genome sequences. A. Unrooted maximum-likelihood tree based on 108 conserved protein sequences (for construction of the tree and references to the genomes, see Methods and Additional file 2, respectively). Bootstraps are 100, unless indicated otherwise. B. Percentual presence of the four gene categories: orphans (dark blue); singletons (cyan); phage- or integrase-related genes (red); and duplicated genes or paralogs (light blue). Genome sizes are indicated on the right.
Lee et al. BMC Genomics 2008 9:271 doi:10.1186/1471-2164-9-271