Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Seit Februar 2021 bietet Wolfgang Brandt, ehemaliger Leiter der Arbeitsgruppe Computerchemie am IPB, sein Citizen Science-Projekt zur Pilzbestimmung an. Dafür hat er in regelmäßigen Abständen öffentliche Vorträge zur Vielfalt…
Vierheilig, H.; Maier, W.; Wyss, U.; Samson, J.; Strack, D.; Piché, Y.;Cyclohexenone derivative- and phosphate-levels in split-root systems and their role in the systemic suppression of mycorrhization in precolonized barley plantsJ. Plant Physiol.157593-599(2000)DOI: 10.1016/S0176-1617(00)80001-2
In a split-root system root colonization by the arbuscular mycorrhizal fungus Glomus mosseae on one side is reduced when roots on the other side are already colonized by G. mosseae. Root colonization by arbuscular mycorrhizal fungi enhances the P-status of plants, thus the observed suppressional effect on further root colonization in precolonized barley plants could be P-level regulated. Split-root systems allow to separate plant mediated P-effects on root colonization by arbuscular mycorrhizal fungi from direct P-effects on arbuscular mycorrhizal fungi. By adding a KH2PO4-solution to one side of the split-root system of non-mycorrhizal control plants, higher P-levels were obtained as in split-root systems of G. mosseae precolonized plants. Subsequent inoculation with G. mosseae of the P-supplied and the precolonized plants resulted in an inhibition of root colonization in the precolonized plants, but not in the P-supplied plants, discarding the enhanced P-level as the responsible factor for the observed suppression. Cyclohexenone derivatives are secondary plant compounds only found in roots of mycorrhizal plants. Analysis of cyclohexenone derivatives in mycorrhizal and non-mycorrhizal roots in split-root systems revealed that cyclohexenone derivatives can be detected in mycorrhizal roots, but not in non-mycorrhizal roots of mycorrhizal plants. The presented results show clearly that cyclohexenone derivatives are not systemically accumulated and that the P-levels are not the responsible factors for the observed systemic suppression of mycorrhization in roots of precolonized barley plants.
Publikation
Maier, W.; Baumert, A.; Gröger, D.;Partial Purification and Characterization of S-Adenosyl-L- Methionine:Anthranilic Acid N-Methyltransferase from Ruta Cell Suspension CulturesJ. Plant Physiol.1451-6(1995)DOI: 10.1016/S0176-1617(11)81837-7
S-Adenosyl-L-methionine: anthranilic acid N-methyltransferase has been purified from cell suspensioncultures of Ruta graveolens by using a combination of gel filtration and ion exchange chromatography. This particular N-methyltransferase, which catalyzes the first pathway specific step in acridone alkaloid biosynthesis, was purified 370-fold. The enzyme has a pH optimum of 7.8, a Mr of 70,000 on gel filtration and a Mr of 62,000 on SDS-PAGE. The properties, the substrate specificity and the Michaelis-Menten constants of the purified enzyme were determined. The anthranilic acid specific N-methyltransferase is strongly inhibited by S-adenosyl-L-homocysteine.