@article{ZhangSampathkumarKerberetal.2020, author = {Zhang, Youjun and Sampathkumar, Arun and Kerber, Sandra Mae-Lin and Swart, Corn{\´e} and Hille, Carsten and Seerangan, Kumar and Graf, Alexander and Sweetlove, Lee and Fernie, Alisdair R.}, title = {A moonlighting role for enzymes of glycolysis in the co-localization of mitochondria and chloroplasts}, series = {Nature Communications}, volume = {11}, journal = {Nature Communications}, issn = {2041-1723}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-14812}, pages = {4509}, year = {2020}, abstract = {Glycolysis is one of the primordial pathways of metabolism, playing a pivotal role in energy metabolism and biosynthesis. Glycolytic enzymes are known to form transient multi-enzyme assemblies. Here we examine the wider protein-protein interactions of plant glycolytic enzymes and reveal a moonlighting role for specific glycolytic enzymes in mediating the co-localization of mitochondria and chloroplasts. Knockout mutation of phosphoglycerate mutase or enolase resulted in a significantly reduced association of the two organelles. We provide evidence that phosphoglycerate mutase and enolase form a substrate-channelling metabolon which is part of a larger complex of proteins including pyruvate kinase. These results alongside a range of genetic complementation experiments are discussed in the context of our current understanding of chloroplast-mitochondrial interactions within photosynthetic eukaryotes.}, language = {en} } @article{BruunHille2019, author = {Bruun, Kristina and Hille, Carsten}, title = {Study on intracellular delivery of liposome encapsulated quantum dots using advanced fluorescence microscopy}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, issn = {2045-2322}, doi = {10.1038/s41598-019-46732-5}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-12476}, pages = {10504}, year = {2019}, abstract = {Quantum dots increasingly gain popularity for in vivo applications. However, their delivery and accumulation into cells can be challenging and there is still lack of detailed information. Thereby, the application of advanced fluorescence techniques can expand the portfolio of useful parameters for a more comprehensive evaluation. Here, we encapsulated hydrophilic quantum dots into liposomes for studying cellular uptake of these so-called lipodots into living cells. First, we investigated photophysical properties of free quantum dots and lipodots observing changes in the fluorescence decay time and translational diffusion behaviour. In comparison to empty liposomes, lipodots exhibited an altered zeta potential, whereas their hydrodynamic size did not change. Fluorescence lifetime imaging microscopy (FLIM) and fluorescence correlation spectroscopy (FCS), both combined with two-photon excitation (2P), were used to investigate the interaction behaviour of lipodots with an insect epithelial tissue. In contrast to the application of free quantum dots, their successful delivery into the cytosol of salivary gland duct cells could be observed when applying lipodots. Lipodots with different lipid compositions and surface charges did not result in considerable differences in the intracellular labelling pattern, luminescence decay time and diffusion behaviour. However, quantum dot degradation after intracellular accumulation could be assumed from reduced luminescence decay times and blue-shifted luminescence signals. In addition to single diffusing quantum dots, possible intracellular clustering of quantum dots could be assumed from increased diffusion times. Thus, by using a simple and manageable liposome carrier system, 2P-FLIM and 2P-FCS recording protocols could be tested, which are promising for investigating the fate of quantum dots during cellular interaction.}, language = {en} } @article{GuentherKlaussToroNahuelpanetal.2019, author = {G{\"u}nther, Erika and Klauß, Andr{\´e} and Toro-Nahuelpan, Mauricio and Sch{\"u}ler, Dirk and Hille, Carsten and Faivre, Damien}, title = {The in vivo mechanics of the magnetotactic backbone as revealed by correlative FLIM-FRET and STED microscopy}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, issn = {2045-2322}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-14802}, year = {2019}, abstract = {Protein interaction and protein imaging strongly benefit from the advancements in time-resolved and superresolution fluorescence microscopic techniques. However, the techniques were typically applied separately and ex vivo because of technical challenges and the absence of suitable fluorescent protein pairs. Here, we show correlative in vivo fluorescence lifetime imaging microscopy F{\"o}rster resonance energy transfer (FLIM-FRET) and stimulated emission depletion (STED) microscopy to unravel protein mechanics and structure in living cells. We use magnetotactic bacteria as a model system where two proteins, MamJ and MamK, are used to assemble magnetic particles called magnetosomes. The filament polymerizes out of MamK and the magnetosomes are connected via the linker MamJ. Our system reveals that bacterial filamentous structures are more fragile than the connection of biomineralized particles to this filament. More importantly, we anticipate the technique to find wide applicability for the study and quantification of biological processes in living cells and at high resolution.}, language = {en} }