Distribution of predicted protein functions in the universal and nonuniversal subsets of the archaeal COGs. (Blue bars) The universal subset (543 COGs with four members each); (red bars) the nonuniversal subset (783 COGs with two or three members each). (Vertical axis) Number of COGs; (horizontal axis) functional categories: 1, translation, ribosome structure, and biogenesis; 2, transcription; 3, DNA replication, repair, recombination; 4, energy production and methanogenesis; 5, amino acid metabolism; 6, nucleotide metabolism; 7, carbohydrate metabolism; 8, coenzyme metabolism; 9, lipid metabolism; 10, molecular chaperones and related functions; 11, cell wall biogenesis and cell division; 12, secretion and motility; 13, inorganic ion transport; 14, general functional prediction only; 15, no functional prediction.
