title: Comparative genomics, minimal gene-sets and the last universal common ancestor.
abstract: Comparative genomics, using computational and experimental methods, enables the identification of a minimal set of genes that is necessary and sufficient for sustaining a functional cell. For most essential cellular functions, two or more unrelated or distantly related proteins have evolved; only about 60 proteins, primarily those involved in translation, are common to all cellular life. The reconstruction of ancestral life-forms is based on the principle of evolutionary parsimony, but the size and composition of the reconstructed ancestral gene-repertoires depend on relative rates of gene loss and horizontal gene-transfer. The present estimate suggests a simple last universal common ancestor with only 500-600 genes.
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, NIH Building 38A, 8600 Rockville Pike, Bethesda, Maryland 20894, USA. koonin@ncbi.nlm.nih.gov
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Koonin
mesh_terms: D001419:Bacteria / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D019295:Computational Biology; D005057:Eukaryotic Cells; D019143:Evolution, Molecular; D020043:Genes, Essential; D023281:Genomics; D011506:Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D011506:Proteins