Köster, Sarah

[["dc.bibliographiccitation.artnumber","088102"],["dc.bibliographiccitation.firstpage","3"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Physical Review Letters"],["dc.bibliographiccitation.lastpage","7"],["dc.bibliographiccitation.volume","112"],["dc.contributor.author","Weinhausen, Britta"],["dc.contributor.author","Saldanha, Oliva"],["dc.contributor.author","Wilke, Robin N."],["dc.contributor.author","Dammann, Christian"],["dc.contributor.author","Priebe, Marius"],["dc.contributor.author","Burghammer, Manfred"],["dc.contributor.author","Sprung, Michael"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2017-09-07T11:46:29Z"],["dc.date.available","2017-09-07T11:46:29Z"],["dc.date.issued","2014"],["dc.description.abstract","High-resolution x-ray imaging techniques offer a variety of possibilities for studying the nanoscale structure of biological cells. A challenging task remains the study of cells by x rays in their natural, aqueous environment. Here, we overcome this limitation by presenting scanning x-ray diffraction measurements with beam sizes in the range of a few hundred nm on living and fixed-hydrated eukaryotic cells in microfluidic devices which mimic a native environment. The direct comparison between fixed-hydrated and living cells shows distinct differences in the scattering signal, pointing to structural changes on the order of 30 to 50 nm."],["dc.identifier.doi","10.1103/PhysRevLett.112.088102"],["dc.identifier.gro","3142182"],["dc.identifier.isi","000331957600012"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5443"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","1079-7114"],["dc.relation.issn","0031-9007"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","cellular biophysics"],["dc.subject.gro","microfluidics"],["dc.title","Scanning X-Ray Nanodiffraction on Living Eukaryotic Cells in Microfluidic Environments"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3914"],["dc.bibliographiccitation.issue","16"],["dc.bibliographiccitation.journal","Journal of Cell Science"],["dc.bibliographiccitation.lastpage","3920"],["dc.bibliographiccitation.volume","125"],["dc.contributor.author","Schwarz G. Henriques, Sarah"],["dc.contributor.author","Sandmann, Rabea"],["dc.contributor.author","Strate, Alexander"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2017-09-07T11:48:27Z"],["dc.date.available","2017-09-07T11:48:27Z"],["dc.date.issued","2012"],["dc.description.abstract","Contraction at the cellular level is vital for living organisms. The most prominent type of contractile cells are heart muscle cells, a less-well-known example is blood platelets. Blood platelets activate and interlink at injured blood vessel sites, finally contracting to form a compact blood clot. They are ideal model cells to study the mechanisms of cellular contraction, as they are simple, having no nucleus, and their activation can be triggered and synchronized by the addition of thrombin. We have studied contraction using human blood platelets, employing traction force microscopy, a single-cell technique that enables time-resolved measurements of cellular forces on soft substrates with elasticities in the physiological range (similar to 4 kPa). We found that platelet contraction reaches a steady state after 25 min with total forces of similar to 34 nN. These forces are considerably larger than what was previously reported for platelets in aggregates, demonstrating the importance of a single-cell approach for studies of platelet contraction. Compared with other contractile cells, we find that platelets are unique, because force fields are nearly isotropic, with forces pointing toward the center of the cell area."],["dc.identifier.doi","10.1242/jcs.108126"],["dc.identifier.gro","3142481"],["dc.identifier.isi","000309525300022"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8762"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0021-9533"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","cellular biophysics"],["dc.title","Force field evolution during human blood platelet activation"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","336"],["dc.bibliographiccitation.issue","S2"],["dc.bibliographiccitation.journal","Microscopy and Microanalysis"],["dc.bibliographiccitation.lastpage","339"],["dc.bibliographiccitation.volume","24"],["dc.contributor.author","Wittmeier, Andrew"],["dc.contributor.author","Cassini, Chiara"],["dc.contributor.author","Hémonnot, Clément Y. J."],["dc.contributor.author","Weinhausen, Britta"],["dc.contributor.author","Bernhardt, Marten"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2020-04-23T14:35:13Z"],["dc.date.available","2020-04-23T14:35:13Z"],["dc.date.issued","2018"],["dc.identifier.doi","10.1017/S1431927618013983"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/64328"],["dc.language.iso","en"],["dc.relation.eissn","1435-8115"],["dc.relation.issn","1431-9276"],["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.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","cellular biophysics"],["dc.title","Scanning Small-Angle-X-Ray Scattering for Imaging Biological Cells"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3053"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","Biochimica et Biophysica Acta (BBA) - Molecular Cell Research"],["dc.bibliographiccitation.lastpage","3064"],["dc.bibliographiccitation.volume","1853"],["dc.contributor.author","Block, Johanna"],["dc.contributor.author","Schroeder, Viktor"],["dc.contributor.author","Pawelzyk, Paul"],["dc.contributor.author","Willenbacher, Norbert"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2017-09-07T11:43:27Z"],["dc.date.available","2017-09-07T11:43:27Z"],["dc.date.issued","2015"],["dc.description.abstract","Intermediate filaments (IFs) constitute a sophisticated filament system in the cytoplasm of eukaryotes. They form bundles and networks with adapted viscoelastic properties and are strongly interconnected with the other filament types, microfilaments and microtubules. IFs are cell type specific and apart from biochemical functions, they act as mechanical entities to provide stability and resilience to cells and tissues. We review the physical properties of these abundant structural proteins including both in vitro studies and cell experiments. IFs are hierarchical structures and their physical properties seem to a large part be encoded in the very specific architecture of the biopolymers. Thus, we begin our review by presenting the assembly mechanism, followed by the mechanical properties of individual filaments, network and structure formation due to electrostatic interactions, and eventually the mechanics of in vitro and cellular networks. This article is part of a Special Issue entitled: Mechanobiology."],["dc.identifier.doi","10.1016/j.bbamcr.2015.05.009"],["dc.identifier.gro","3141801"],["dc.identifier.isi","000363069200010"],["dc.identifier.pmid","25975455"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/1223"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","0006-3002"],["dc.relation.issn","0167-4889"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","cytoskeleton"],["dc.subject.gro","cellular biophysics"],["dc.title","Physical properties of cytoplasmic intermediate filaments"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","705"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Acta crystallographica. Section D, Structural biology"],["dc.bibliographiccitation.lastpage","717"],["dc.bibliographiccitation.volume","72"],["dc.contributor.author","Tauchert, Marcel J."],["dc.contributor.author","Hémonnot, Clément"],["dc.contributor.author","Neumann, Piotr"],["dc.contributor.author","Köster, Sarah"],["dc.contributor.author","Ficner, Ralf"],["dc.contributor.author","Dickmanns, Achim"],["dc.date.accessioned","2020-12-10T18:26:04Z"],["dc.date.available","2020-12-10T18:26:04Z"],["dc.date.issued","2016"],["dc.description.abstract","In eukaryotic cells, the exchange of macromolecules between the nucleus and cytoplasm is highly selective and requires specialized soluble transport factors. Many of them belong to the importin-beta superfamily, the members of which share an overall superhelical structure owing to the tandem arrangement of a specific motif, the HEAT repeat. This structural organization leads to great intrinsic flexibility, which in turn is a prerequisite for the interaction with a variety of proteins and for its transport function. During the passage from the aqueous cytosol into the nucleus, the receptor passes the gated channel of the nuclear pore complex filled with a protein meshwork of unknown organization, which seems to be highly selective owing to the presence of FG-repeats, which are peptides with hydrophobic patches. Here, the structural changes of free importin-beta from a single organism, crystallized in polar (salt) or apolar (PEG) buffer conditions, are reported. This allowed analysis of the structural changes, which are attributable to the surrounding milieu and are not affected by bound interaction partners. The importin-beta structures obtained exhibit significant conformational changes and suggest an influence of the polarity of the environment, resulting in an extended conformation in the PEG condition. The significance of this observation is supported by SAXS experiments and the analysis of other crystal structures of importin-beta deposited in the Protein Data Bank."],["dc.identifier.doi","10.1107/S2059798316004940"],["dc.identifier.fs","622294"],["dc.identifier.gro","3141673"],["dc.identifier.isi","000379911500002"],["dc.identifier.issn","2059-7983"],["dc.identifier.pmid","27303791"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/75940"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","2059-7983"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","molecular biophysics"],["dc.title","Impact of the crystallization condition on importin-β conformation"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","82"],["dc.bibliographiccitation.journal","Current Opinion in Cell Biology"],["dc.bibliographiccitation.lastpage","91"],["dc.bibliographiccitation.volume","32"],["dc.contributor.author","Köster, Sarah"],["dc.contributor.author","Weitz, David A."],["dc.contributor.author","Goldman, Robert D."],["dc.contributor.author","Aebi, Ueli"],["dc.contributor.author","Herrmann, Harald"],["dc.date.accessioned","2017-09-07T11:44:38Z"],["dc.date.available","2017-09-07T11:44:38Z"],["dc.date.issued","2015"],["dc.description.abstract","Intermediate filament proteins form filaments, fibers and networks both in the cytoplasm and the nucleus of metazoan cells. Their general structural building plan accommodates highly varying amino acid sequences to yield extended dimeric alpha-helical coiled coils of highly conserved design. These 'rod' particles are the basic building blocks of intrinsically flexible, filamentous structures that are able to resist high mechanical stresses, that is, bending and stretching to a considerable degree, both in vitro and in the cell. Biophysical and computer modeling studies are beginning to unfold detailed structural and mechanical insights into these major supramolecular assemblies of cell architecture, not only in the 'test tube' but also in the cellular and tissue context."],["dc.identifier.doi","10.1016/j.ceb.2015.01.001"],["dc.identifier.gro","3141962"],["dc.identifier.isi","000351309500012"],["dc.identifier.pmid","25621895"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/3013"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","1879-0410"],["dc.relation.issn","0955-0674"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","cytoskeleton"],["dc.subject.gro","cellular biophysics"],["dc.title","Intermediate filament mechanics in vitro and in the cell: from coiled coils to filaments, fibers and networks"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2974"],["dc.bibliographiccitation.issue","16"],["dc.bibliographiccitation.journal","Lab on a Chip"],["dc.bibliographiccitation.lastpage","2976"],["dc.bibliographiccitation.volume","16"],["dc.contributor.author","Schroeder, Charles M."],["dc.contributor.author","Köster, Sarah"],["dc.contributor.author","Huang, Yanyi"],["dc.date.accessioned","2017-09-07T11:54:44Z"],["dc.date.available","2017-09-07T11:54:44Z"],["dc.date.issued","2016"],["dc.identifier.doi","10.1039/c6lc90076c"],["dc.identifier.gro","3141750"],["dc.identifier.isi","000382144000001"],["dc.identifier.pmid","27447687"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/657"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","1473-0189"],["dc.relation.issn","1473-0197"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","other"],["dc.title","Emerging Investigators 2016"],["dc.title.subtitle","Discovery science meets technology"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","439"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","The European Physical Journal E - Soft Matter"],["dc.bibliographiccitation.lastpage","449"],["dc.bibliographiccitation.volume","25"],["dc.contributor.author","Köster, Sarah"],["dc.contributor.author","Kierfeld, Jan"],["dc.contributor.author","Pfohl, Thomas"],["dc.date.accessioned","2017-09-07T11:48:46Z"],["dc.date.available","2017-09-07T11:48:46Z"],["dc.date.issued","2008"],["dc.description.abstract","Confinement effects on single semiflexible macromolecules are of central importance for a fundamental understanding of cellular processes involving biomacromolecules. To analyze the influence of confinement on the fluctuations of semiflexible macromolecules we study individual actin filaments in straight and curved microchannels. We experimentally characterize the segment distributions for fluctuating semiflexible filaments in microchannels as a function of the channel width. Moreover, the effect of channel curvature on the filament fluctuations is investigated. We find quantitative agreement between experimental results, Monte Carlo simulations, and the analytical description. This allows for determination of the persistence length of actin filaments, the deflection length, which characterizes the confinement effects, and the scaling exponents for the segment distribution of semiflexible macromolecules."],["dc.identifier.doi","10.1140/epje/i2007-10312-3"],["dc.identifier.gro","3143323"],["dc.identifier.isi","000255867900010"],["dc.identifier.pmid","18425410"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/825"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1292-8941"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","cytoskeleton"],["dc.subject.gro","cellular biophysics"],["dc.subject.gro","microfluidics"],["dc.title","Characterization of single semiflexible filaments under geometric constraints"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2059"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Soft Matter"],["dc.bibliographiccitation.lastpage","2068"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Brennich, Martha Elisabeth"],["dc.contributor.author","Bauch, Susanne"],["dc.contributor.author","Vainio, Ulla"],["dc.contributor.author","Wedig, Tatjana"],["dc.contributor.author","Herrmann, Harald"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2017-09-07T11:46:55Z"],["dc.date.available","2017-09-07T11:46:55Z"],["dc.date.issued","2014"],["dc.description.abstract","The assembly kinetics of intermediate filament (IF) proteins from tetrameric complexes to single filaments and networks depends on the protein concentration, temperature and the ionic composition of their environment. We systematically investigate how changes in the concentration of monovalent potassium and divalent magnesium ions affect the internal organization of the resulting filaments. Small angle X-ray scattering (SAXS) is very sensitive to changes in the filament cross-section such as diameter or compactness. Our measurements reveal that filaments formed in the presence of magnesium chloride differ distinctly from filaments formed in the presence of potassium chloride. The principle multi-step assembly mechanism from tetramers via unit-length filaments (ULF) to elongated filaments is not changed by the valency of ions. However, the observed differences indicate that the magnesium ions free the head domains of tetramers from unproductive interactions to allow assembly but at the same time mediate strong inter-tetrameric interactions that impede longitudinal annealing of unit-length filaments considerably, thus slowing down filament growth."],["dc.identifier.doi","10.1039/c3sm52532e"],["dc.identifier.gro","3142216"],["dc.identifier.isi","000332463300021"],["dc.identifier.pmid","24800271"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5821"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","1744-6848"],["dc.relation.issn","1744-683X"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","cytoskeleton"],["dc.subject.gro","molecular biophysics"],["dc.title","Impact of ion valency on the assembly of vimentin studied by quantitative small angle X-ray scattering"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Schepers, Anna V."],["dc.contributor.author","Lorenz, Charlotta"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2020-03-03T08:22:25Z"],["dc.date.available","2020-03-03T08:22:25Z"],["dc.date.issued","2019"],["dc.description.abstract","The cytoskeleton is formed by three types of filamentous proteins – microtubules, actin filaments, and intermediate filaments (IFs) – and enables cells to withstand external and internal forces. Vimentin is the most abundant IF in humans and has remarkable mechanical properties, such as high extensibility and stability. It is, however, unclear to which extent these properties are influenced by the electrostatic environment. Here, we study the mechanical properties of single vimentin filaments by employing optical trapping combined with microfluidics. Force-strain curves, recorded at varying ion concentrations and pH values, reveal that the mechanical properties of single vimentin IFs are influenced by direct (pH) and indirect (ionic) charge variations. By combination with Monte Carlo simulations, we connect these altered mechanics to electrostatic interactions of subunits within the filaments. We thus find possible mechanisms that allow cells to locally tune their stiffness without remodelling the entire cytoskeleton."],["dc.identifier.doi","10.1101/784025"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63070"],["dc.language.iso","en"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","membrane biophysics"],["dc.title","Tuning intermediate filament mechanics by indirect and direct charge variations"],["dc.type","preprint"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]