Hagemann, Johannes

[["dc.bibliographiccitation.firstpage","10661"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","ACS Nano"],["dc.bibliographiccitation.lastpage","10670"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Hémonnot, Clément Y. J."],["dc.contributor.author","Ranke, Christiane"],["dc.contributor.author","Saldanha, Oliva"],["dc.contributor.author","Graceffa, Rita"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2017-11-28T10:03:27Z"],["dc.date.available","2017-11-28T10:03:27Z"],["dc.date.issued","2016"],["dc.description.abstract","X-ray imaging of intact biological cells is emerging as a complementary method to visible light or electron microscopy. Owing to the high penetration depth and small wavelength of X-rays, it is possible to resolve subcellular structures at a resolution of a few nanometers. Here, we apply scanning X-ray nanodiffraction in combination with time-lapse bright-field microscopy to nuclei of 3T3 fibroblasts and thus relate the observed structures to specific phases in the cell division cycle. We scan the sample at a step size of 250 nm and analyze the individual diffraction patterns according to a generalized Porod’s law. Thus, we obtain information on the aggregation state of the nuclear DNA at a real space resolution on the order of the step size and in parallel structural information on the order of few nanometers. We are able to distinguish nucleoli, heterochromatin, and euchromatin in the nuclei and follow the compaction and decompaction during the cell division cycle."],["dc.identifier.doi","10.1021/acsnano.6b05034"],["dc.identifier.fs","623722"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/10593"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.eissn","1936-086X"],["dc.relation.issn","1936-0851"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject","biological cells; cell division cycle; DNA compaction; nanostructure; X-ray nanodiffraction"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","cellular biophysics"],["dc.title","Following DNA Compaction During the Cell Cycle by X-ray Nanodiffraction"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","unknown"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","518"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","529"],["dc.bibliographiccitation.volume","28"],["dc.contributor.affiliation","Wittmeier, Andrew; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Cassini, Chiara; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Töpperwien, Mareike; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Denz, Manuela; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Hagemann, Johannes; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Osterhoff, Markus; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Salditt, Tim; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.author","Wittmeier, Andrew"],["dc.contributor.author","Cassini, Chiara"],["dc.contributor.author","Töpperwien, Mareike"],["dc.contributor.author","Denz, Manuela"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2021-04-14T08:28:23Z"],["dc.date.available","2021-04-14T08:28:23Z"],["dc.date.issued","2021"],["dc.date.updated","2022-02-09T13:21:31Z"],["dc.description.abstract","X‐rays are emerging as a complementary probe to visible‐light photons and electrons for imaging biological cells. By exploiting their small wavelength and high penetration depth, it is possible to image whole, intact cells and resolve subcellular structures at nanometer resolution. A variety of X‐ray methods for cell imaging have been devised for probing different properties of biological matter, opening up various opportunities for fully exploiting different views of the same sample. Here, a combined approach is employed to study cell nuclei of NIH‐3T3 fibroblasts. Scanning small‐angle X‐ray scattering is combined with X‐ray holography to quantify length scales, aggregation state, and projected electron and mass densities of the nuclear material. Only by joining all this information is it possible to spatially localize nucleoli, heterochromatin and euchromatin, and physically characterize them. It is thus shown that for complex biological systems, like the cell nucleus, combined imaging approaches are highly valuable."],["dc.description.abstract","The combination of small‐angle X‐ray scattering and X‐ray holography enables us to visualize and characterize biological material in cell nuclei spanning multiple length scales. image"],["dc.identifier.doi","10.1107/S1600577520016276"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/82591"],["dc.identifier.url","https://mbexc.uni-goettingen.de/literature/publications/218"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.publisher","International Union of Crystallography"],["dc.relation","EXC 2067: Multiscale Bioimaging"],["dc.relation.eissn","1600-5775"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","This is an open access article under the terms of the Creative Commons Attribution License, which permits use,\r\n distribution and reproduction in any medium, provided the original work is properly cited."],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","cellular biophysics"],["dc.title","Combined scanning small-angle X-ray scattering and holography probes multiple length scales in cell nuclei"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1196"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","1205"],["dc.bibliographiccitation.volume","25"],["dc.contributor.author","Nicolas, Jan-David"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Sprung, Michael"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2020-12-10T18:25:58Z"],["dc.date.available","2020-12-10T18:25:58Z"],["dc.date.issued","2018"],["dc.description.abstract","For almost half a century, optical tweezers have successfully been used to micromanipulate micrometre and sub-micrometre-sized particles. However, in recent years it has been shown experimentally that, compared with single-beam traps, the use of two opposing and divergent laser beams can be more suitable in studying the elastic properties of biological cells and vesicles. Such a configuration is termed an optical stretcher due to its capability of applying high deforming forces on biological objects such as cells. In this article the experimental capabilities of an optical stretcher as a potential sample delivery system for X-ray diffraction and imaging studies at synchrotrons and X-ray free-electron laser (FEL) facilites are demonstrated. To highlight the potential of the optical stretcher its micromanipulation capabilities have been used to image polymer beads and label biological cells. Even in a non-optimized configuration based on a commercially available optical stretcher system, X-ray holograms could be recorded from different views on a biological cell and the three-dimensional phase of the cell could be reconstructed. The capability of the setup to deform cells at higher laser intensities in combination with, for example, X-ray diffraction studies could furthermore lead to interesting studies that couple structural parameters to elastic properties. By means of high-throughput screening, the optical stretcher could become a useful tool in X-ray studies employing synchrotron radiation, and, at a later stage, femtosecond X-ray pulses delivered by X-ray free-electron lasers."],["dc.identifier.doi","10.1107/S1600577518006574"],["dc.identifier.issn","1600-5775"],["dc.identifier.pmid","29979182"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/75896"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.relation.eissn","1600-5775"],["dc.relation.issn","1600-5775"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.title","The optical stretcher as a tool for single-particle X-ray imaging and diffraction"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]