title: The fusion of genomes leads to more options: A comparative investigation on the desulfo-glucosinolate sulfotransferases of Brassica napus and homologous proteins of Arabidopsis thaliana.
abstract: Sulfotransferases (SOTs) (EC 2.8.2.-) play a crucial role in the glucosinolate (Gl) biosynthesis, by catalyzing the final step of the core glucosinolate formation. In Arabidopsis thaliana the three desulfo (ds)-Gl SOTs AtSOT16, AtSOT17 and AtSOT18 were previously characterized, showing different affinities to ds-Gls. But can the knowledge about these SOTs be generally transferred to other Gl-synthesizing plants? It was investigated how many SOTs are present in the economically relevant crop plant Brassica napus L., and if it is possible to predict their characteristics by sequence analysis. The recently sequenced B. napus is a hybrid of Brassica rapa and Brassica oleracea. By database research, 71 putative functional BnSOT family members were identified and at least eleven of those are putative ds-Gl SOTs. Besides the homologs of AtSOT16 - 18, phylogenetic analyses revealed new subfamilies of ds-Gl SOTs, which are not present in A. thaliana. Three of the B. napus ds-Gl SOT proteins were expressed and purified, and characterized by determining the substrate affinities to different ds-Gls. Two of them, BnSOT16-a and BnSOT16-b, showed a significantly higher affinity to an indolic ds-Gl, similarly to AtSOT16. Additionally, BnSOT17-a was characterized and showed a higher affinity to long chained aliphatic Gls, similarly to AtSOT17. Identification of homologs to AtSOT18 was less reliable, because putative SOT18 sequences are more heterogeneous and confirmation of similar characteristics was not possible.
authors.affiliation: Institute of Botany, Leibniz University Hannover, Herrenhäuserstr. 2, D-30419 Hannover, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Hirschmann
authors.affiliation: Institute of Botany, Leibniz University Hannover, Herrenhäuserstr. 2, D-30419 Hannover, Germany. Electronic address: Jutta.Papenbrock@botanik.uni-hannover.de.
authors.forename: Jutta
authors.initials: J
authors.lastname: Papenbrock
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000737:chemistry*; D001483:Base Sequence; D029688:Brassica napus / Q000201:enzymology / Q000235:genetics*; D019295:Computational Biology; D030541:Databases, Genetic; D018628:Gene Dosage; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D005961:Glucosinolates / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry; D013379:Substrate Specificity; D015238:Sulfotransferases / Q000737:chemistry*
chemical_list: D029681:Arabidopsis Proteins; D005961:Glucosinolates; D010940:Plant Proteins; D015238:Sulfotransferases
keywords: Brassica napus; Copy number variation; Glucosinolate; Sulfotransferase