title: Metabolic fluxes in an illuminated Arabidopsis rosette.
abstract: Photosynthesis is the basis for life, and its optimization is a key biotechnological aim given the problems of population explosion and environmental deterioration. We describe a method to resolve intracellular fluxes in intact Arabidopsis thaliana rosettes based on time-dependent labeling patterns in the metabolome. Plants photosynthesizing under limiting irradiance and ambient CO2 in a custom-built chamber were transferred into a (13)CO2-enriched environment. The isotope labeling patterns of 40 metabolites were obtained using liquid or gas chromatography coupled to mass spectrometry. Labeling kinetics revealed striking differences between metabolites. At a qualitative level, they matched expectations in terms of pathway topology and stoichiometry, but some unexpected features point to the complexity of subcellular and cellular compartmentation. To achieve quantitative insights, the data set was used for estimating fluxes in the framework of kinetic flux profiling. We benchmarked flux estimates to four classically determined flux signatures of photosynthesis and assessed the robustness of the estimates with respect to different features of the underlying metabolic model and the time-resolved data set.
authors: Central Metabolism Research Group, Max-Planck-Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany.
authors: Marek
authors: M
authors: Szecowka
authors: Robert
authors: R
authors: Heise
authors: Takayuki
authors: T
authors: Tohge
authors: Adriano
authors: A
authors: Nunes-Nesi
authors: Daniel
authors: D
authors: Vosloh
authors: Jan
authors: J
authors: Huege
authors: Regina
authors: R
authors: Feil
authors: John
authors: J
authors: Lunn
authors: Zoran
authors: Z
authors: Nikoloski
authors: Mark
authors: M
authors: Stitt
authors: Alisdair R
authors: AR
authors: Fernie
authors: Stéphanie
authors: S
authors: Arrivault
mesh_terms: D017360:Arabidopsis / Q000254:growth & development* / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D002245:Carbon Dioxide / Q000737:chemistry; D002247:Carbon Isotopes; D002451:Cell Compartmentation; D008401:Gas Chromatography-Mass Spectrometry; D007294:Inositol / Q000737:chemistry / Q000378:metabolism; D007553:Isotope Labeling / Q000379:methods; D007700:Kinetics; D055442:Metabolome; D008954:Models, Biological; D008967:Molecular Biology / Q000379:methods; D010788:Photosynthesis; D013213:Starch / Q000378:metabolism
chemical_list: D002247:Carbon Isotopes; D002245:Carbon Dioxide; D007294:Inositol; D013213:Starch