Liposomes as versatile tools : adaptation of bacteriophage therapy against intracellular bacterial pathogens by liposomal vectorization and liposomal analysis of synthetic glycolipids as surface receptors$nElektronische Ressource Zusammenfassung: The emergence of antibiotic resistant bacteria presents a severe challenge to medicine and public health. While bacteriophage therapy is a promising alternative to traditional antibiotics the general inability of bacteriophages to penetrate eukaryotic cells limits their use against resistant bacteria causing intracellular diseases like tuberculosis. Bacterial vectors show some promise in carrying therapeutic bacteriophages into cells but also bring a number of risks like an overload of bacterial antigens or the acquisition of virulence genes from the pathogen. Here I take first steps in the development of a possible non bacterial vector by demonstrating the effective encapsulation of the model bacteriophage λeyfp and the mycobacteriophage TM4 into liposomes. Furthermore I show that liposome associated bacteriophages are taken up into cultured eukaryotic cells more efficiently than free bacteriophages and co localize with early and recycling endosomes after uptake. Also the influence of the lipid composition of liposomes on bacteriophage uptake is analysed. Finally in two in vitro infection models the impact of GUV delivered lytic bacteriophages on intracellular bacterial counts of Mycobacterium bovis BCG and Listeria monocytogenes is investigated. These are important milestones in the development of an intracellular bacteriophage therapy that might be useful in the fight against multi resistant intracellular pathogens like Mycobacterium tuberculosis.In addition in two side projects the suitability of synthetic glycolipids as artificial surface receptors is analysed and the sensitivity of the causative agent of Johne’s disease in ruminants Mycobacterium avium subspecies paratuberculosis to two mycobacteriophages is investigated