A5074987930- Formal Methods in Verification
- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- Logic, programming, and type systems
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- High-pressure geophysics and materials
- X-ray Spectroscopy and Fluorescence Analysis
- Embedded Systems Design Techniques
- Model-Driven Software Engineering Techniques
- Crystal Structures and Properties
- RNA modifications and cancer
- Parallel Computing and Optimization Techniques
- Interconnection Networks and Systems
- Software Testing and Debugging Techniques
- RNA and protein synthesis mechanisms
- Lipid Membrane Structure and Behavior
- Logic, Reasoning, and Knowledge
- Liquid Crystal Research Advancements
- Lysosomal Storage Disorders Research
- Nanoparticle-Based Drug Delivery
- Electron and X-Ray Spectroscopy Techniques
- CCD and CMOS Imaging Sensors
- Gold and Silver Nanoparticles Synthesis and Applications
- Libraries and Information Services
Helmholtz-Zentrum Berlin für Materialien und Energie
2016-2025
Humboldt-Universität zu Berlin
2023
Johannes Gutenberg University Mainz
2015-2020
Karlsruhe Institute of Technology
1978-2016
German Research Centre for Artificial Intelligence
2000-2016
Medizinische Hochschule Hannover
2014
Ludwig-Maximilians-Universität München
1997-2013
Max Planck Institute for Solid State Research
2013
Nanosystems Initiative Munich
2013
Center for NanoScience
2013
Vesicular nucleo-cytoplasmic transport is becoming recognized as a general cellular mechanism for translocation of large cargoes across the nuclear envelope. Cargo recruited, enveloped at inner membrane (INM), and delivered by fusion outer membrane. To understand structural underpinning this trafficking, we investigated egress progeny herpesvirus capsids where capsid envelopment mediated two viral proteins, forming complex (NEC). Using multi-modal imaging approach, visualized NEC in situ...
Abstract Electrocatalysts alter their structure and composition during reaction, which can in turn create new active/selective phases. Identifying these changes is crucial for determining how morphology controls catalytic properties but the mechanisms by operating conditions shape catalyst’s working state are not yet fully understood. In this study, we show using correlated operando microscopy spectroscopy that as well-defined Cu 2 O cubes evolve under electrochemical nitrate reduction...
Low-dimensional nanostructures offer a host of intriguing properties which are distinct from those the bulk material, owing to size-confinement effects and amplified surface areas. Here, we report on scalable, bottom-up synthesis ultrathin coordination polymer nanosheets via surfactant-mediated subsequent exfoliation. Layers two-dimensional (2D) zinc self-assembled in interlamellar space reverse microemulsion mesophase into stacks interleaved with cethyltrimethylammonium bromide (CTAB) at...
We present an x-ray optical approach to overcome the current limitations in spatial resolution of microscopes. Our new BESSY full-field microscope operates with energy up E/DeltaE=10(4). demonstrate that under these conditions it is possible employ high orders diffraction for imaging. Using third order a zone plate objective 25 nm outermost width, 14 lines and spaces multilayer test structure were clearly resolved. believe high-order imaging paves way towards sub-10-nm real space
Cryo-soft X-ray tomography (cryo-SXT) is a powerful imaging technique that can extract ultrastructural information from whole, unstained mammalian cells as close to the living state possible. Subcellular organelles including nucleus, Golgi apparatus and mitochondria have been identified by morphology alone, due similarity in contrast transmission electron micrographs. In this study, we used cryo-SXT image endosomes autophagosomes, are particularly susceptible chemical fixation artefacts...
Significance The most widely used antimalarial drugs belong to the quinoline family. question of their mode action has been open for centuries. It recently narrowed down whether these interfere with process crystallization heme in malaria parasite. To date, all studies drug on crystals have done either model systems or dried parasites, which yielded limited data and ambiguity. This study was actual parasites near-native environment, revealing vivo. approach adopted this can be extended other...
Soft X-ray cryo-microscopy/tomography of vitreous samples is becoming a valuable tool in structural cell biology. Within the 'water-window' wavelength region (2.34-4.37nm), it provides absorption contrast images with high signal to noise ratio and resolution few tens nanometer. X-rays wavelengths close K-absorption edge oxygen penetrate biological thicknesses micrometer range. Here, we report on application recently established extension transmission soft cryo-microscope (HZB TXM) at...
Abstract Methods for the detection of RNA modifications are fundamental importance advancing epitranscriptomics. N 6 ‐methyladenosine (m A) is most abundant modification in mammalian mRNA and involved regulation gene expression. Current techniques laborious rely on antibody‐based enrichment m A‐containing prior to sequencing, since A generally “erased” during reverse transcription (RT). To overcome drawbacks associated with indirect detection, we aimed generate novel DNA polymerase variants...
Abstract Reverse transcription (RT) of RNA templates containing modifications leads to synthesis cDNA information on the modification in form misincorporation, arrest, or nucleotide skipping events. A compilation such events from multiple cDNAs represents an RT-signature that is typical for a given modification, but, as we show here, depends also reverse transcriptase enzyme. comparison 13 different enzymes revealed range RT-signatures, with individual exhibiting average arrest rates between...
The achievable spatial resolution and the contrast transfer function (CTF) are key parameters characterizing an X-ray microscope. We measured of transmission microscope (TXM) at electron storage ring BESSY II. TXM uses radiation undulator source operates under partially coherent illumination conditions. For resolutions down to 25 nm, our measurements CTF's in good agreement with theoretical CTF data for partial coherence. With higher zone plate objectives, we a (half-pitch) 11 nm 1st 3rd...
Abstract Recently discovered new chemical entities in RNA modifications have involved surprising functional groups that enlarge the space of RNA. Using LC‐MS, we found over 100 signals constituents contained a ribose moiety tRNAs from E. coli . Feeding experiments with variegated stable isotope labeled compounds identified 37 are structures modifications. One structure was elucidated by deuterium exchange and high‐resolution mass spectrometry. The msms 2 i 6 A...
Drugs that influence enzymes of lipid metabolism can cause pathological accumulation lipids in animal cells. Here, gold nanoparticles, acting as nanosensors deliver surface-enhanced Raman scattering (SERS) spectra from living cells provide molecular evidence lysosomes after treatment cultured with the three tricyclic antidepressants (TCA) desipramine, amitryptiline, and imipramine. The vibrational elucidate to great detail very high sensitivity composition drug-induced accumulations, also...
We correlate the localization of silver nanoparticles inside cells with respect to cellular architecture molecular information in vicinity particle surface by combining nanoscale 3D cryo-soft X-ray tomography (cryo-SXT) surface-enhanced Raman scattering (SERS). The interaction nanoparticle small molecules and biopolymers was monitored SERS vitro over time living cells. spectra indicate a stable, time-independent composition nanoparticles, despite changing environment endosomal structure....
We report on the synthesis and exfoliation of MnIIAlIII sulfonate sulfate layered double hydroxides (LDHs) their combination with graphene oxide by charge-directed self-assembly. The LDH compounds has been accomplished either directly coprecipitation respective anions or ion-exchange chloride-containing sodium dodecylsulfate. Exfoliation bulk material in formamide yields colloidal suspensions positively charged nanosheets lateral dimensions tens to hundreds nanometers thicknesses down 1.3...
Tomographic reconstruction in soft x-ray microscopy is a powerful technique for obtaining high-resolution 3D images of biological samples. However, the depth focus such zone-plate-based microscopes typically shorter than thickness many relevant objects, challenging validity projection assumption used conventional algorithms. In order to make full use microscopes' high resolution, tomographic needs take into account. Here we present method achieve resolution sample when short compared...
Methods for the detection of m6A by RNA-Seq technologies are increasingly sought after. We here present NOseq, a method to detect residues in defined amplicons virtue their resistance chemical deamination, effected nitrous acid. Partial deamination NOseq affects all exocyclic amino groups nucleobases and thus also changes sequence information. The uses mapping algorithm specifically adapted degeneration caused events. Thus, sites with partial modification levels ∼50% were detected amplicons,...
The complex architecture of their structural elements and compartments is a hallmark eukaryotic cells. creation high resolution models whole cells has been limited by the relatively low conventional light microscopes requirement for ultrathin sections in transmission electron microscopy. We used soft x-ray tomography to study 3D ultrastructural organization unicellular green alga Chlamydomonas reinhardtii at unprecedented spatial resolution. Intact frozen hydrated were imaged using natural...
Correlative fluorescence and soft X-ray cryo-microscopy/tomography on flat sample holders is perfectly suited to study the uncompromised physiological status of adherent cells at its best possible preservation by imaging after fast cryo-immobilization. To understand mechanism which herpesviruses induce nucleoplasmic reticulum, i.e. invaginations nuclear envelope, during their egress from host cell nucleus, morphologically similar structures found in laminopathies chemical induction were...
Fourier transform holography is a highly efficient and robust imaging method, suitable for single-shot at coherent X-ray sources. In its common implementation, the image contrast limited by reference signal generated small pinhole aperture. Increased diameters improve signal, whereas resolution diminished. Here we report new concept to decouple spatial from employing Fresnel zone plate provide beam. Superimposed on-axis images of distinct foci are separated with novel algorithm. Our method...