title: The phylogenetic extent of metabolic enzymes and pathways.
abstract: The evolution of metabolic enzymes and pathways has been a subject of intense study for more than half a century. Yet, so far, previous studies have focused on a small number of enzyme families or biochemical pathways. Here, we examine the phylogenetic distribution of the full-known metabolic complement of Escherichia coli, using sequence comparison against taxa-specific databases. Half of the metabolic enzymes have homologs in all domains of life, representing families involved in some of the most fundamental cellular processes. We thus show for the first time and in a comprehensive way that metabolism is conserved at the enzyme level. In addition, our analysis suggests that despite the sequence conservation and the extensive phylogenetic distribution of metabolic enzymes, their groupings into biochemical pathways are much more variable than previously thought.
authors.affiliation: Computational Genomics Group, The European Bioinformatics Institute, EMBL Cambridge Outstation, Cambridge CB10 1SD, UK.
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Peregrin-Alvarez
authors.forename: Sophia
authors.initials: S
authors.lastname: Tsoka
authors.forename: Christos A
authors.initials: CA
authors.lastname: Ouzounis
mesh_terms: D000818:Animals; D001105:Archaea / Q000201:enzymology / Q000235:genetics; D004798:Enzymes / Q000235:genetics* / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D056890:Eukaryota / Q000201:enzymology / Q000235:genetics; D019143:Evolution, Molecular; D005658:Fungi / Q000201:enzymology / Q000235:genetics; D010802:Phylogeny; D014780:Viruses / Q000201:enzymology / Q000235:genetics
chemical_list: D004798:Enzymes