Photorespiratory Hydroxypyruvate Metabolism in Arabidopsis

• Applicant: Professor Dr. Hermann Bauwe
• Subject Area: Plant Physiology
• Term: from 2006 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 22465762

Most land plants, in the photorespiratory C2 cycle, produce very large daily amounts of 3-hydroxypyruvate (3HP). There is agreement in the scientific literature that these large amounts of 3HP are exclusively metabolized by the peroxisomal enzyme NADH:3HP reductase (HPR1). In contrast to this current consensus, we have shown in preliminary studies with Arabidopsis HPR1 knockout plants the existence of an additional 3HP metabolizing pathway of remarkable capacity. The project attempts to identify the enzymes, genes, and metabolites which are involved in this yet unknown pathway of plant primary metabolism. This will be achieved by a combined biochemical and genetical approach including protein purification and characterization, generation of double and triple mutants, metabolic flux and detailed metabolome analyses, as well as by quantitatively assessing gas-exchange parameters of whole leaves.

• DFG Programme: Research Grants