title: Metabolic responses of Thellungiella halophila/salsuginea to biotic and abiotic stresses: metabolite profiles and quantitative analyses.
abstract: The metabolite profiles of the model crucifer Thellungiella salsuginea (salt cress) ecotype Shandong subjected to various biotic and abiotic stresses were analyzed using HPLC-DAD-ESI-MS. Two different cruciferous microbial pathogens, Albugo candida, a biotrophic oomycete, and Leptosphaeria maculans, a necrotrophic fungus, elicited formation of the phytoalexins wasalexins A and B without causing visual damage on inoculated leaves. Analyses of non-polar and polar metabolites led to elucidation of the chemical structures of five metabolites: 4'-O-(E)-sinapoyl-7-methoxyisovitexin-2''-O-beta-D-glucopyranoside, 4'-O-(E)-sinapoylisovitexin-2''-O-beta-D-glucopyranoside, 4-O-beta-D-glucopyranosyl-7-hydroxymatairesinol, 5'-O-beta-D-glucopyranosyldihydroneoascorbigen and 3-O-beta-D-glucopyranosylthiane. 3-O-beta-D-glucopyranosylthiane, an unique metabolite for which we suggest the name glucosalsuginin, is proposed to derive from the glucosinolate glucoberteroin. In addition, the identification of a broad range of polar metabolites identical to those of other crucifers was carried out. Quantification of several metabolites over a period of eight days showed that concentrations of the polar phytoanticipin 4-methoxyglucobrassicin increased substantially in leaves irradiated with UV light (lambda(max) 254 nm) relative to control leaves, but not in leaves subjected to other stresses.
authors.affiliation: Department of Chemistry, University of Saskatchewan, Saskatoon, SK, Canada. s.pedras@usask.ca
authors.forename: M Soledade C
authors.initials: MS
authors.lastname: Pedras
authors.forename: Qing-An
authors.initials: QA
authors.lastname: Zheng
mesh_terms: D000222:Adaptation, Physiological; D019607:Brassicaceae / Q000378:metabolism* / Q000382:microbiology / Q000528:radiation effects; D005658:Fungi / Q000472:pathogenicity; D005960:Glucosides / Q000378:metabolism; D005961:Glucosinolates / Q000378:metabolism; D007211:Indoles / Q000378:metabolism; D008027:Light; D055442:Metabolome; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000528:radiation effects; D010940:Plant Proteins / Q000378:metabolism*; D012717:Sesquiterpenes / Q000378:metabolism; D013312:Stress, Physiological; D013440:Sulfides / Q000378:metabolism; D014466:Ultraviolet Rays; D000094162:Phytoalexins
chemical_list: D005960:Glucosides; D005961:Glucosinolates; D007211:Indoles; D010940:Plant Proteins; D012717:Sesquiterpenes; D013440:Sulfides; C552248:glucosalsuginin; C403468:methoxyglucobrassicin; C401941:wasalexin A; D000094162:Phytoalexins