||P.6 right column bottom paragraph: "The added sensitivity derived from the COGs analysis arises because COGs are not dependent on BLAST cutoff scores and arbitrary sequence-relatedness criteria: genes with relatively unimpressive sequence identity can be placed into an orthology group. Some interesting facts arose from this analysis [primary source]. First, 55-83% of proteins encoded by bacterial and archaeal genomes can be placed into discrete COGs, suggesting that many genes present in bacteria and archaea are highly conserved." Primary source p.103 bottom paragraph: "The current collection of COGs shows two striking and, in a sense, opposing trends that are relevant for the discussion of the minimal-gene-set concept (35: link ). First, it is notable that 55%–83% of the proteins encoded in each of the bacterial and archaeal genomes belong to the COGs, which, it should be emphasized, by definition include representatives of at least three phylogenetically distant clades (Table 1)."