title: Evolutionary relationships among extradiol dioxygenases.
abstract: A structure-validated alignment of 35 extradiol dioxygenase sequences including two-domain and one-domain enzymes was derived. Strictly conserved residues include the metal ion ligands and several catalytically essential active site residues, as well as a number of structurally important residues that are remote from the active site. Phylogenetic analyses based on this alignment indicate that the ancestral extradiol dioxygenase was a one-domain enzyme and that the two-domain enzymes arose from a single genetic duplication event. Subsequent divergence among the two-domain dioxygenases has resulted in several families, two of which are based on substrate preference. In several cases, the two domains of a given enzyme express different phylogenies, suggesting the possibility that such enzymes arose from the recombination of genes encoding different dioxygenases. A phylogeny-based classification system for extradiol dioxygenases is proposed.
authors.affiliation: Department of Biochemistry, Université Laval, Québec City, Canada. leltis@rsvs.ulaval.ca
authors.forename: L D
authors.initials: LD
authors.lastname: Eltis
authors.forename: J T
authors.initials: JT
authors.lastname: Bolin
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D017124:Conserved Sequence; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D005810:Multigene Family; D010105:Oxygenases / Q000145:classification*; D010802:Phylogeny; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D010105:Oxygenases