Nutrient availability and in particular nitrogen availability in the soil is often limiting plant growth. Apart from efficient nitrogen-uptake mechanisms, plants also need to possess effective means to redistribute nitrogen during every stage of development. Most prominent are redistribution processes during germination when the seed cannot yet acquire nutrients from the environment but also during senescence when the great majority of nitrogen stored in the leaves is exported to sustain flowering and seed or storage organ development.
Gene discovery has exploded in recent years and whole genome sequences are now available for several organisms including plants. However, the elucidation of gene function is progressing at a slower rate. We are interested in identifying enzymes involved in nitrogen conversions in plants and to elucidate their physiological function. To identify new enzymes we are combining bioinformatic methods for enzyme functional prediction with protein biochemistry for functional testing. Physiological characterisations are based on the analysis of mutants as well as enzyme expression and localisation studies under different environmental conditions and during plant development.