E. coli entry clone libray construction and comparative ORFeomics. (A) Pipeline used to clone the E. coli ORFs into Gateway® Entry vector (pENTR/Zeo). The total number of ORFs in common between E. coli K-12 MG1655 and E. coli K-12 W3110 is based on the more accurate sequencing of these strains  and community re-annotation . (B) Pairwise comparison of Clusters of orthologous genes (COGs) in all species pairs. Colors indicate the similarity between species. For example, E. coli shares at least 60% of its COGs with most other species. The species in the rows are ordered such that similar rows are near each other. (C) Presence of COGs in 14 species with available ORFeomes. For example, 370 COGs are present in exactly 5 species (bars and left scale). The line represents the number of COGs that are present in a minimal number of species, e.g. 2162 COGs are present in 4 or more species (right scale).
Rajagopala et al. BMC Genomics 2010 11:470 doi:10.1186/1471-2164-11-470