Evolutionary relationships among extradiol dioxygenases.

L D Eltis; J T Bolin

doi:10.1128/jb.178.20.5930-5937.1996

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Evolutionary relationships among extradiol dioxygenases.

L D Eltis·J T Bolin

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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.

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Amino Acid Sequence Binding Sites Conserved Sequence Evolution, Molecular Molecular Sequence Data Multigene Family Oxygenases Phylogeny Sequence Alignment Sequence Homology, Amino Acid Comparative Study Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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L D Eltis, J T Bolin. 1996. Evolutionary relationships among extradiol dioxygenases.. https://doi.org/10.1128/jb.178.20.5930-5937.1996

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