title: Glutathione transferase-like proteins encoded in genomes of yeasts and fungi: insights into evolution of a multifunctional protein superfamily.
abstract: Most fungal glutathione transferases (GSTs) do not fit easily into any of the previously characterised classes by immunological, sequence or catalytic criteria. In contrast to the paucity of studies on GSTs cloned or isolated from fungal sources, a screen of databases revealed 67 GST-like sequences from 21 fungal species. Comparison by multiple sequence alignment generated a dendrogram revealing five clusters of GST-like proteins designated clusters 1, 2, EFIBgamma, Ure2p and MAK16, the last three of which have previously been related to the GST superfamily. Surprisingly, a relatively small number of fungal GSTs belong to mainstream classes and the previously-described fungal Gamma class is not widespread in the 21 species studied. Representative crystal structures are available for the EFIBgamma and Ure2p classes and the domain structures of representative sequences are compared with these. In addition, there are some "orphan" sequences that do not fit into any previously-described class, but show similarity to genes implicated in fungal biosynthetic gene clusters. We suggest that GST-like sequences are widespread in fungi, participating in a wide range of functions. They probably evolved by a process similar to domain "shuffling".
authors.affiliation: Department of Biochemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Lee Maltings, Prospect Row, Mardyke, Cork, Ireland.
authors.forename: Shane
authors.initials: S
authors.lastname: McGoldrick
authors.forename: Siobhàn M
authors.initials: SM
authors.lastname: O'Sullivan
authors.forename: David
authors.initials: D
authors.lastname: Sheehan
mesh_terms: D000595:Amino Acid Sequence; D019295:Computational Biology; D017124:Conserved Sequence / Q000235:genetics; D019143:Evolution, Molecular; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics; D005658:Fungi / Q000201:enzymology* / Q000235:genetics; D005800:Genes, Fungal; D016681:Genome, Fungal; D005982:Glutathione Transferase / Q000737:chemistry / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D005656:Fungal Proteins; D005982:Glutathione Transferase