A glutathione transferase from Agrobacterium tumefaciens reveals a novel class of bacterial GST superfamily

dc.contributor.advisor	Skopelitou, Katholiki	en
dc.contributor.advisor	Σκοπελίτου, Καθολική	el
dc.contributor.author	Dhavala, Prathusha	en
dc.contributor.author	Papageorgiou, Anastassios C.	en
dc.contributor.author	Labrou, Nikolaos E.	en
dc.contributor.author	Παπαγεωργίου, Αναστάσιος Γ.	el
dc.contributor.author	Λάμπρου, Νικόλαος Ε.	el
dc.date.accessioned	2014-06-06T06:52:13Z
dc.date.available	2014-06-06T06:52:13Z
dc.date.issued	2012-04-04	en
dc.identifier.issn	19326203	en
dc.identifier.uri	http://dx.doi.org/10.1371/journal.pone.0034263	en
dc.identifier.uri	http://62.217.125.90/xmlui/handle/123456789/5908
dc.rights	CC0 1.0 Παγκόσμια	el
dc.rights.uri	http://creativecommons.org/publicdomain/zero/1.0/	en
dc.title	A glutathione transferase from Agrobacterium tumefaciens reveals a novel class of bacterial GST superfamily	en
heal.type	journalArticle	en
heal.keyword	Glutathione derivative	en
heal.keyword	Glutathione transferase H1 1	en
heal.keyword	Catalysis	en
heal.keyword	Enzyme kinetics	en
heal.keyword	Enzyme mechanism	en
heal.keyword	Enzyme substrate complex	en
heal.keyword	Escherichia coli	en
heal.keyword	Phylogeny	en
heal.keyword	Rhizobium radiobacter	en
heal.keyword	X ray	en
heal.keyword	Crystallography	en
heal.keyword	Agrobacterium tumefaciens	en
heal.keyword	Eukaryota	en
heal.keyword	Prokaryota	en
heal.keyword	Amino Acid Sequence	en
heal.identifier.primary	10.1371/journal.pone.0034263	en
heal.identifier.secondary	e34263	en
heal.recordProvider	Γεωπονικό Πανεπιστήμιο Αθηνών/Επιστήμη Γεωπονικής Βιοτεχνολογίας	el
heal.recordProvider	University of Turku, Abo Akademi University Finland/Centre for Biotechnology	en
heal.publicationDate	2012-04-04	en
heal.bibliographicCitation	Skopelitou, Katholiki. A glutathione transferase from Agrobacterium tumefaciens reveals a novel class of bacterial GST superfamily, PLoS One, vol. 7 (4), pp 1-10, PLoS 2012	en
heal.abstract	In the present work, we report a novel class of glutathione transferases (GSTs) originated from the pathogenic soil bacterium Agrobacterium tumefaciens C58, with structural and catalytic properties not observed previously in prokaryotic and eukaryotic GST isoenzymes. A GST-like sequence from A. tumefaciens C58 (Atu3701) with low similarity to other characterized GST family of enzymes was identified. Phylogenetic analysis showed that it belongs to a distinct GST class not previously described and restricted only in soil bacteria, called the Eta class (H). This enzyme (designated as AtuGSTH1-1) was cloned and expressed in E. coli and its structural and catalytic properties were investigated. Functional analysis showed that AtuGSTH1-1 exhibits significant transferase activity against the common substrates aryl halides, as well as very high peroxidase activity towards organic hydroperoxides. The crystal structure of AtuGSTH1-1 was determined at 1.4 Å resolution in complex with S-(p-nitrobenzyl)-glutathione (Nb-GSH). Although AtuGSTH1-1 adopts the canonical GST fold, sequence and structural characteristics distinct from previously characterized GSTs were identified. The absence of the classic catalytic essential residues (Tyr, Ser, Cys) distinguishes AtuGSTH1-1 from all other cytosolic GSTs of known structure and function. Site-directed mutagenesis showed that instead of the classic catalytic residues, an Arg residue (Arg34), an electron-sharing network, and a bridge of a network of water molecules may form the basis of the catalytic mechanism. Comparative sequence analysis, structural information, and site-directed mutagenesis in combination with kinetic analysis showed that Phe22, Ser25, and Arg187 are additional important residues for the enzyme's catalytic efficiency and specificity. © 2012 Skopelitou et al.	en
heal.publisher	Public Library of Science (PLoS)	en
heal.journalName	PLoS ONE	en
dc.identifier.doi	10.1371/journal.pone.0034263	en