His research aims at establishing fundamental concepts of endocytosis and intracellular trafficking. The Johannes team has made two major contributions in this context: The discovery of the membrane trafficking interface between early endosomes and the Golgi apparatus which has since become a focus of cell biology research, and the demonstration that dynamic lectin-induced glycolipid reorganization acts as a driving force for endocytic pit construction in clathrin-independent endocytosis. The latter was termed GlycoLipid-Lectin (GL-Lect) hypothesis. The studies of the Johannes team are very well cited and have been published in several highly visible journals, including Cell, Nature, Nature Cell Biology, and Nature Nanotechnology. Between 2014-2020, he was the holder of an ERC advanced grant. He also aims at exploiting the discoveries of his team in fundamental membrane biology research for the development of innovative cancer therapy strategies. His team has notably validated the B-subunit of Shiga toxin (STxB) as a "pilot" for the delivery of therapeutic compounds to precise intracellular locations of dendritic cells for immunotherapy, and to tumors for targeted therapy (12 patent families, 5 of which are delivered in the US, Europe and other countries; creation of biotech companies).