Molybdenum (Mo) is an essential micronutrient for almost all living beings. Mo participates as cofactor (Moco) in the active site of more than 50 Mo-enzymes that are involved in vital processes such as inorganic nitrogen assimilation, sulphur metabolism, phytohormone biosynthesis, and stress reactions. Mo is acquired by cells in form of the anion molybdate. Molybdate transport process is well known in bacteria, poorly characterized in plants, algae and fungi, and unknown in animals. In animals Moco deficiency leads to a neuronal damage and finally to an early death. Using the green algae Chlamydomonas and on the basis of his previous experience in the identification of the first eukaryotic molybdate transporter (MoT1), the candidate has identified a putative molybdate transporter in humans (C2H2). The main aim of the research project is to characterize the molybdate transport process mediated by the human protein C2HS. This includes the determination of putative interactions of this protein with other proteins like gephyrin, the subcellular localization of C2HS and its tree-dimensional structure. The proposed project will be developed by the applicant in the Institute of Biochemistry of the University of Cologne under supervision of Prof. G. Schwarz. The quality of the infrastructures and facilities of the University of Cologne, the experience of the host group in the field, as well as a good defined work plan supporter by an appropriated methodology, guarantee a good training for the candidate that will be crucial for him to obtain the skills necessaries to reach a position of professional maturity.