Fraunhofer-Institut für Atmosphärische Umweltforschung IFU

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  • Publication
    Long term effects of naturally elevated CO2, H2S and SO2 on sulphur allocation in Quercus
    ( 1997)
    Schulte, M.
    ;
    Herschbach, C.
    ;
    Rennenberg, H.
    The thiol composition and contents were analysed in oak trees growing at sites with naturally elevated atmospheric CO2 and sulphur concentrations. Exposure to these gases leads to enhanced thiol contents in metabolically active tissues such as leaves and bark. In both tissues GSH was the predominant thiol. The additional reduced sulphur in leaves and bark seems to originate from atmospheric sulphur influx, since sulphur contents of the xylem sap remained unchanged. In contrast to xylem sap, GSH contents of phloem exudates decreased at elevated compared to ambient CO2 and sulphur independent of the site studied. Enhanced thiol contents in the bark, but reduced thiol contents in the phloem under elevated CO2 and sulphur indicate that reduced sulphur from atmospheric influx is partially stored in the bark and may not be allocated to the root.
  • Publication
    Molecular approaches to glutathione biosynthesis
    ( 1997)
    Rennenberg, H.
    The thiol tripeptide glutathione is synthesized in plants from the constituent amino acids in two enzyme catalyzed reaction steps. The properties and the regulation of both enzymes, namely gamma-glutamyl-cysteine synthetase (EC 6.3.2.2) and glutathione synthetase (EC 6.3.2.3), have been analyzed by classical biochemical studies and, recently, by plant molecular biology techniques. In the present review, the results achieved by these approaches are compared and a preliminary scheme for the regulation of cytosolic glutathione levels in plants is suggested with special emphasis on the interaction between the pathways of assimilatory sulphate reduction and glutathione biosynthesis.
  • Publication
    Sulfur nutrition of conifers and deciduous trees
    ( 1997)
    Herschbach, C.
    ;
    Rennenberg, H.
  • Publication
    Role of ozone in forest decline on Wank mountain (Alps)
    ( 1997)
    Rennenberg, H.
    ;
    Polle, A.
    ;
    Reuther, M.
  • Publication
    Consequences of chronic ozone exposure in transgenic poplars overexpressing enzymes of the glutathione metabolism
    ( 1997)
    Will, B.
    ;
    Eiblmeier, M.
    ;
    Langebartels, C.
    ;
    Rennenberg, H.
    Transgenic poplar trees overexpressing different enzymes of the glutathione metabolism, namely glutathione synthetase, glutathione reductase and gamma-glutamyl-cysteine synthetase (gamma-EC synthetase) were subjected to chronic ozone exposure. After four weeks of fumigation, all lines clearly showed visible damage, compared to controls fumigated with ambient air. However, none of the transgenic lines overexpressing the different enzymes of glutathione metabolism showed enhanced resistance towards ozone. Even the line overexpressing gamma-EC synthetase, which had about 2-fold enhanced glutathione contents, did not show a lower level of damage upon ozone exposure. There was no change in glutathione contents due to ozone fumigation. Apparently, enhanced glutathione content or elevated glutathione reducing capacity does not protect poplar trees from damage derived from chronic ozone exposure. Glutathione does not seem to play a crucial role in detoxifying reactive oxygen species under thes e conditions.
  • Publication
    Gasförmige Schwefelverbindungen
    ( 1994)
    Rennenberg, H.
  • Publication
    Emission of N-oxides from acid irrigated and limed soils of a coniferous forest in Bavaria
    ( 1993)
    Papen, H.
    ;
    Hellmann, B.
    ;
    Papke, H.
    ;
    Rennenberg, H.
  • Publication
  • Publication
    Glutathione metabolism in plants
    ( 1993)
    Bergmann, L.
    ;
    Rennenberg, H.