title: New members of the glutathione transferase family discovered in red and brown algae.
abstract: The GSTs (glutathione transferases) are involved in the detoxification of a wide variety of hydrophobic substrates. These enzymes have been found in virtually all types of organisms, including plants, animals, nematodes and bacteria. In the present study, we report the molecular and biochemical characterization of algal GSTs. Phylogenetic analysis showed that most of them were distinct from previously described GST classes, but were most closely related to the Sigma class. Profiling of GST genes from the red alga Chondrus crispus and brown alga Laminaria digitata was undertaken after different chemical treatments and showed that they displayed contrasting patterns of transcription. Recombinant algal GST from both species showed transferase activities against the common substrates aryl halides, but also on the alpha,beta-unsaturated carbonyl 4-hydroxynonenal. Also, they exhibit significant peroxidation towards organic hydroperoxides, including oxygenated derivatives of polyunsaturated fatty acids. Among a range of compounds tested, Cibacron Blue was the most efficient inhibitor of algal GSTs identified.
authors.affiliation: UPMC Univ. Paris 6, UMR 7139 Végétaux Marins et Biomolécules, Station Biologique, F 29682, Roscoff, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Hervé
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: de Franco
authors.forename: Agnès
authors.initials: A
authors.lastname: Groisillier
authors.forename: Thierry
authors.initials: T
authors.lastname: Tonon
authors.forename: Catherine
authors.initials: C
authors.lastname: Boyen
mesh_terms: D020418:Algal Proteins / Q000737:chemistry*; D000595:Amino Acid Sequence; D018076:DNA, Complementary / Q000378:metabolism; D005982:Glutathione Transferase / Q000737:chemistry*; D008969:Molecular Sequence Data; D000459:Phaeophyceae / Q000201:enzymology*; D010802:Phylogeny; D000461:Rhodophyta / Q000201:enzymology*; D016415:Sequence Alignment; D014158:Transcription, Genetic
chemical_list: D020418:Algal Proteins; D018076:DNA, Complementary; D005982:Glutathione Transferase