A5008622925- Advanced Electron Microscopy Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- DNA and Nucleic Acid Chemistry
- RNA and protein synthesis mechanisms
- Bacteriophages and microbial interactions
- Photosynthetic Processes and Mechanisms
- Advanced X-ray Imaging Techniques
- Force Microscopy Techniques and Applications
- Enzyme Structure and Function
- Geometric and Algebraic Topology
- Ion-surface interactions and analysis
- Genomics and Chromatin Dynamics
- Advanced biosensing and bioanalysis techniques
- Molecular Biology Techniques and Applications
- Lipid Membrane Structure and Behavior
- Nanopore and Nanochannel Transport Studies
- Spectroscopy and Quantum Chemical Studies
- Bacterial Genetics and Biotechnology
- Photoreceptor and optogenetics research
- Genomics and Phylogenetic Studies
- semigroups and automata theory
- Pickering emulsions and particle stabilization
- Education, sociology, and vocational training
- Kidney Stones and Urolithiasis Treatments
- RNA Interference and Gene Delivery
University of Lausanne
2004-2023
Redress
2018
University of St. Thomas - Minnesota
2009
European Bioinformatics Institute
1981-2008
University of Geneva
1970-2005
École Polytechnique Fédérale de Lausanne
2003-2005
The University of Queensland
2004
Université Joseph Fourier
2004
Inserm
2004
University of California, Santa Barbara
2003
What are the components that control assembly of subcellular organelles in eukaryotic cells? Although membranes can clearly be distorted by cytosolic factors, very little is known about intrinsic mechanisms biogenesis, shape, and organization organellar membranes. Here, we found unconventional phospholipid lysobisphosphatidic acid (LBPA) could induce formation multivesicular liposomes resembled endosomes exist where this lipid vivo. This process depended on same pH gradient exists across...
SUMMARY Thin layers of pure water or aqueous solutions are frozen in the vitreous state with phase form hexagonal cubic crystals, either by using a spray‐freezing method spreading liquid on alkylamine treated films. The specimens observed conventional and scanning transmission electron microscope at temperatures down to 25 K. In general, formation crystals segregation solutes during freezing, devitrification evaporation upon warming, take place as foreseen previous X‐ray, thermal, optical...
ABSTRACT The cell envelope of mycobacteria, which include the causative agents tuberculosis and leprosy, is crucial for their success as pathogens. Despite a continued strong emphasis on identifying multiple chemical components this envelope, it has proven difficult to combine its into comprehensive structural model, primarily because available ultrastructural data rely conventional electron microscopy embedding sectioning, are known induce artifacts. existence an outer membrane bilayer long...
Although the formation of 30-nm chromatin fibers is thought to be most basic event compaction, it remains controversial because high-resolution imaging in living eukaryotic cells had not been possible until now. Cryo-electron microscopy vitreous sections a relatively new technique, which enables direct observation cell structures close-to-native state. We used cryo-electron and image processing further investigate presence human mitotic chromosomes. HeLa S3 were vitrified by high-pressure...
High-pressure freezing of Escherichia coli K-12 and Pseudomonas aeruginosa PAO1 in the presence cryoprotectants provided consistent vitrification cells so that frozen-hydrated sections could be cut, providing approximately 2-nm resolution structure. The size shape bacteria, as well their surface cytoplasmic constituents, were nicely preserved compared with other published high-resolution techniques. Cells possessed a rich cytoplasm containing diffuse dispersion ribosomes genetic material....
The preparation and high resolution observation of frozen hydrated thin sections has been studied by transmission electron microscopy (TEM STEM) on model systems, including pure water, protein solutions, catalase crystals, myelin sheath various tissues. state the ice is determined diffraction. Mass measurement in microscope used to determine section thickness control hydration. An adequate depth vitrified material for sectioning can be obtained from many biological suspensions or untreated...
Amorphous, unstained, frozen-hydrated sections of bacteria provide a faithful high-resolution image procaryotic cells. Conventional preparation artifacts due to fixation, staining, and dehydration are nonexistent. Freezing damage is avoided by using glucose as cryoprotectant. Cutting on frozen material severe, but sectioning artifacts, being always related the cutting direction, can be systematically recognized thus taken into consideration. Geometry density distribution bacterial envelope...
Cryo-electron microscopy of vitreous section makes it possible to observe cells and tissues at high resolution in a close-to-native state. The specimen remains hydrated; chemical fixation staining are fully avoided. There is minimal molecular aggregation the density observed image corresponds object. Accordingly, organotypic hippocampal rat slices were vitrified under pressure controlled cryoprotection conditions, cryosectioned final thickness approximately 70 nm below -170 degrees C...
The methodology for preparing specimens in the frozen, hydrated state has been assessed using crystals and T4 bacteriophages. methods have also demonstrated with lambda bacteriophages, purple membrane of Halobacterium halobium fibres DNA. For particles dispersed an aqueous environment, it is shown that optimum structural preservation obtained from a thin, quench-frozen film bulk medium vitreous state. Crystallization water may result solute segregation expulsion specimen film. Contrast...
Hydrophobic quantum dots can be incorporated into the bilayer membrane of lipid vesicles for selective delivery either plasma membranes or cytoplasm living cells (see picture). The cell and integrate any kind hydrophobic nanoparticle whose size matches thickness, thus opening possibilities their manipulation in nanobiotechnology applications.