The portfolio of this BAG includes structural investigation of membrane proteins as well as soluble proteins relevant to various scientific fields. Important basic science projects are concerned with the fundamentals of proton transport and the function of hitherto poorly characterised rhodopsins. In application-related activities we are addressing challenges in biotechnology (development of novel optogenetic tools, optimisation of enzymes for biomimetic synthesis) and medicine (evaluation of innovative autophagy modulators, understanding and preventing protein aggregation in disease).