Witt, Hannes

[["dc.bibliographiccitation.journal","European Biophysics Journal"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Savić, Filip"],["dc.contributor.author","Verbeek, Sarah"],["dc.contributor.author","Dietz, Jörn"],["dc.contributor.author","Tarantola, Gesa"],["dc.contributor.author","Oelkers, Marieelen"],["dc.contributor.author","Geil, Burkhard"],["dc.contributor.author","Janshoff, Andreas"],["dc.date.accessioned","2021-04-14T08:29:19Z"],["dc.date.available","2021-04-14T08:29:19Z"],["dc.date.issued","2021"],["dc.identifier.doi","10.1007/s00249-020-01490-5"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/82863"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.relation.eissn","1432-1017"],["dc.relation.issn","0175-7571"],["dc.title","Membrane fusion studied by colloidal probes"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","eaat1161"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Science Advances"],["dc.bibliographiccitation.volume","4"],["dc.contributor.author","Block, Johanna"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Candelli, Andrea"],["dc.contributor.author","Danes, Jordi Cabanas"],["dc.contributor.author","Peterman, Erwin J. G."],["dc.contributor.author","Wuite, Gijs J. L."],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2019-07-09T11:45:54Z"],["dc.date.available","2019-07-09T11:45:54Z"],["dc.date.issued","2018"],["dc.description.abstract","Structure and dynamics of living matter rely on design principles fundamentally different from concepts of traditional material science. Specialized intracellular filaments in the cytoskeleton permit living systems to divide, migrate, and growwith a high degree of variability and durability. Among the three filament systems,microfilaments,microtubules, and intermediate filaments (IFs), the physical properties of IFs and their role in cellular mechanics are the least well understood. We use optical trapping of individual vimentin filaments to investigate energy dissipation, strain history dependence, and creep behavior of stretched filaments. By stochastic and numerical modeling, we link our experimental observations to the peculiar molecular architecture of IFs. We find that individual vimentin filaments display tensile memory and are able to dissipate more than 70% of the input energy.We attribute these phenomena to distinct nonequilibrium folding and unfolding of a helices in the vimentin monomers constituting the filaments."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2018"],["dc.identifier.doi","10.1126/sciadv.aat1161"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15341"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59334"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","2375-2548"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.rights","CC BY-NC 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0/"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","530"],["dc.subject.gro","cytoskeleton"],["dc.subject.gro","cellular biophysics"],["dc.title","Viscoelastic properties of vimentin originate from nonequilibrium conformational changes"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2278"],["dc.bibliographiccitation.issue","15"],["dc.bibliographiccitation.journal","Biochemistry"],["dc.bibliographiccitation.lastpage","2288"],["dc.bibliographiccitation.volume","57"],["dc.contributor.author","Seiwert, Dennis"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Ritz, Sandra"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Paulsen, Harald"],["dc.date.accessioned","2020-12-10T15:22:31Z"],["dc.date.available","2020-12-10T15:22:31Z"],["dc.date.issued","2018"],["dc.identifier.doi","10.1021/acs.biochem.8b00118"],["dc.identifier.eissn","1520-4995"],["dc.identifier.issn","0006-2960"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/73430"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","The Nonbilayer Lipid MGDG and the Major Light-Harvesting Complex (LHCII) Promote Membrane Stacking in Supported Lipid Bilayers"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","048101"],["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Physical Review Letters"],["dc.bibliographiccitation.lastpage","5"],["dc.bibliographiccitation.volume","118"],["dc.contributor.author","Block, Johanna"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Candelli, Andrea"],["dc.contributor.author","Peterman, Erwin J. G."],["dc.contributor.author","Wuite, Gijs J. L."],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2020-12-10T18:25:42Z"],["dc.date.available","2020-12-10T18:25:42Z"],["dc.date.issued","2017"],["dc.description.abstract","The mechanical properties of eukaryotic cells are to a great extent determined by the cytoskeleton, a composite network of different filamentous proteins. Among these, intermediate filaments (IFs) are exceptional in their molecular architecture and mechanical properties. Here we directly record stress-strain curves of individual vimentin IFs using optical traps and atomic force microscopy. We find a strong loading rate dependence of the mechanical response, supporting the hypothesis that IFs could serve to protect eukaryotic cells from fast, large deformations. Our experimental results show different unfolding regimes, which we can quantitatively reproduce by an elastically coupled system of multiple two-state elements."],["dc.identifier.doi","10.1103/PhysRevLett.118.048101"],["dc.identifier.eissn","1079-7114"],["dc.identifier.fs","623737"],["dc.identifier.issn","0031-9007"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/17056"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/75797"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.relation.eissn","1079-7114"],["dc.relation.issn","0031-9007"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.rights","CC BY 3.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/3.0/"],["dc.subject.gro","cytoskeleton"],["dc.subject.gro","cellular biophysics"],["dc.title","Nonlinear Loading-Rate-Dependent Force Response of Individual Vimentin Intermediate Filaments to Applied Strain"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","unknown"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","22504"],["dc.bibliographiccitation.issue","47"],["dc.bibliographiccitation.journal","Nanoscale"],["dc.bibliographiccitation.lastpage","22519"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Kamprad, Nadine"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Schröder, Marcel"],["dc.contributor.author","Kreis, Christian Titus"],["dc.contributor.author","Bäumchen, Oliver"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Tarantola, Marco"],["dc.date.accessioned","2020-12-10T18:11:24Z"],["dc.date.available","2020-12-10T18:11:24Z"],["dc.date.issued","2018"],["dc.description.abstract","Dictyostelium discoideum cells rely on two different mechanisms for adhesion: wetting through conventional colloidal forces and stochastic nanocluster dynamics."],["dc.description.abstract","Biological adhesion is essential for all motile cells and generally limits locomotion to suitably functionalized substrates displaying a compatible surface chemistry. However, organisms that face vastly varying environmental challenges require a different strategy. The model organism Dictyostelium discoideum ( D.d. ), a slime mould dwelling in the soil, faces the challenge of overcoming variable chemistry by employing the fundamental forces of colloid science. To understand the origin of D.d. adhesion, we realized and modified a variety of conditions for the amoeba comprising the absence and presence of the specific adhesion protein Substrate Adhesion A ( sadA ), glycolytic degradation, ionic strength, surface hydrophobicity and strength of van der Waals interactions by generating tailored model substrates. By employing AFM-based single cell force spectroscopy we could show that experimental force curves upon retraction exhibit two regimes. The first part up to the critical adhesion force can be described in terms of a continuum model, while the second regime of the curve beyond the critical adhesion force is governed by stochastic unbinding of individual binding partners and bond clusters. We found that D.d. relies on adhesive interactions based on EDL-DLVO (Electrical Double Layer-Derjaguin–Landau–Verwey–Overbeek) forces and contributions from the glycocalix and specialized adhesion molecules like sadA . This versatile mechanism allows the cells to adhere to a large variety of natural surfaces under various conditions."],["dc.description.abstract","Dictyostelium discoideum cells rely on two different mechanisms for adhesion: wetting through conventional colloidal forces and stochastic nanocluster dynamics."],["dc.description.abstract","Biological adhesion is essential for all motile cells and generally limits locomotion to suitably functionalized substrates displaying a compatible surface chemistry. However, organisms that face vastly varying environmental challenges require a different strategy. The model organism Dictyostelium discoideum ( D.d. ), a slime mould dwelling in the soil, faces the challenge of overcoming variable chemistry by employing the fundamental forces of colloid science. To understand the origin of D.d. adhesion, we realized and modified a variety of conditions for the amoeba comprising the absence and presence of the specific adhesion protein Substrate Adhesion A ( sadA ), glycolytic degradation, ionic strength, surface hydrophobicity and strength of van der Waals interactions by generating tailored model substrates. By employing AFM-based single cell force spectroscopy we could show that experimental force curves upon retraction exhibit two regimes. The first part up to the critical adhesion force can be described in terms of a continuum model, while the second regime of the curve beyond the critical adhesion force is governed by stochastic unbinding of individual binding partners and bond clusters. We found that D.d. relies on adhesive interactions based on EDL-DLVO (Electrical Double Layer-Derjaguin–Landau–Verwey–Overbeek) forces and contributions from the glycocalix and specialized adhesion molecules like sadA . This versatile mechanism allows the cells to adhere to a large variety of natural surfaces under various conditions."],["dc.identifier.doi","10.1039/C8NR07107A"],["dc.identifier.eissn","2040-3372"],["dc.identifier.issn","2040-3364"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/73995"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.relation.eissn","2040-3372"],["dc.relation.issn","2040-3364"],["dc.rights.uri","http://creativecommons.org/licenses/by/3.0/"],["dc.title","Adhesion strategies of Dictyostelium discoideum – a force spectroscopy study"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","13051"],["dc.bibliographiccitation.issue","46"],["dc.bibliographiccitation.journal","PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA"],["dc.bibliographiccitation.lastpage","13056"],["dc.bibliographiccitation.volume","113"],["dc.contributor.author","Oelkers, Marieelen"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Halder, Partho"],["dc.contributor.author","Jahn, Reinhard"],["dc.contributor.author","Janshoff, Andreas"],["dc.date.accessioned","2018-11-07T10:05:44Z"],["dc.date.available","2018-11-07T10:05:44Z"],["dc.date.issued","2016"],["dc.description.abstract","Fusion of lipid bilayers is usually prevented by large energy barriers arising from removal of the hydration shell, formation of highly curved structures, and, eventually, fusion pore widening. Here, we measured the force-dependent lifetime of fusion intermediates using membrane-coated silica spheres attached to cantilevers of an atomic-force microscope. Analysis of time traces obtained from force-clamp experiments allowed us to unequivocally assign steps in deflection of the cantilever to membrane states during the SNARE-mediated fusion with solid-supported lipid bilayers. Force-dependent lifetime distributions of the various intermediate fusion states allowed us to propose the likelihood of different fusion pathways and to assess the main free energy barrier, which was found to be related to passing of the hydration barrier and splaying of lipids to eventually enter either the fully fused state or a long-lived hemifusion intermediate. The results were compared with SNARE mutants that arrest adjacent bilayers in the docked state and membranes in the absence of SNAREs but presence of PEG or calcium. Only with the WT SNARE construct was appreciable merging of both bilayers observed."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [GSC 226/2, SFB 803 B06, B08]"],["dc.identifier.doi","10.1073/pnas.1615885113"],["dc.identifier.isi","000388970100058"],["dc.identifier.pmid","27807132"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/38957"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Natl Acad Sciences"],["dc.relation.issn","0027-8424"],["dc.title","SNARE-mediated membrane fusion trajectories derived from force-clamp experiments"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Forsting, Johanna"],["dc.contributor.author","Kraxner, Julia"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2020-04-24T12:22:06Z"],["dc.date.available","2020-04-24T12:22:06Z"],["dc.date.issued","2019"],["dc.description.abstract","Intermediate filaments (IFs) are part of the cytoskeleton of eukaryotic cells and are thus largely responsible for the cell's mechanical properties. IFs are characterized by a pronounced extensibility and remarkable resilience that enable them to support cells in extreme situations. Previous experiments showed that under strain, alpha-helices in vimentin IFs might unfold to beta-sheets. Upon repeated stretching, the filaments soften, however, the remaining plastic strain is negligible. Here we observe that vimentin IFs do not recover their original stiffness on reasonable time scales, and we explain these seemingly contradicting results by introducing a third, less well-defined conformational state. Reversibility on a microscopic scale can be fully rescued by introducing crosslinkers that prevent transition to the beta-sheet. Our results classify IFs as a material with intriguing mechanical properties, which is likely to play a major role for the cell's local adaption to external stimuli."],["dc.format.extent","21"],["dc.identifier.doi","10.1101/673673"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/64342"],["dc.language.iso","en"],["dc.subject.gro","cellular biophysics"],["dc.title","Vimentin intermediate filaments undergo irreversible conformational changes during cyclic loading"],["dc.type","preprint"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1582"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","1592"],["dc.bibliographiccitation.volume","110"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Savic, Filip"],["dc.contributor.author","Oelkers, Marieelen"],["dc.contributor.author","Awan, Shahid I."],["dc.contributor.author","Werz, Daniel B."],["dc.contributor.author","Geil, Burkhard"],["dc.contributor.author","Janshoff, Andreas"],["dc.date.accessioned","2018-11-07T10:15:33Z"],["dc.date.available","2018-11-07T10:15:33Z"],["dc.date.issued","2016"],["dc.description.abstract","Weak noncovalent intermolecular interactions play a pivotal role in many biological processes such as cell adhesion or immunology, where the overall binding strength is controlled through bond association and dissociation dynamics as well as the cooperative action of many parallel bonds. Among the various molecules participating in weak bonds, carbohydrate-carbohydrate interactions are probably the most ancient ones allowing individual cells to reversibly enter the multicellular state and to tell apart self and nonself cells. Here, we scrutinized the kinetics and thermodynamics of small homomeric Lewis X-Lewis X ensembles formed in the contact zone of a membrane-coated colloidal probe and a solid supported membrane ensuring minimal nonspecific background interactions. We used an atomic force microscope to measure force distance curves at Piconewton resolution, which allowed us to measure the force due to unbinding of the colloidal probe and the planar membrane as a function of contact time. Applying a contact model, we could estimate the free binding energy of the formed adhesion cluster as a function of dwell time and thereby determine the precise size of the contact zone, the number of participating bonds, and the intrinsic rates of association and dissociation in the presence of calcium ions. The unbinding energy per bond was found to be on the order of 1 k(B)T. Approximately 30 bonds were opened simultaneously at an off-rate of k(off) = 7 +/- 0.2 s(-1)."],["dc.identifier.doi","10.1016/j.bpj.2016.03.006"],["dc.identifier.isi","000374209700012"],["dc.identifier.pmid","27074683"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/40833"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Cell Press"],["dc.relation.issn","1542-0086"],["dc.relation.issn","0006-3495"],["dc.title","Size, Kinetics, and Free Energy of Clusters Formed by Ultraweak Carbohydrate-Carbohydrate Bonds"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","European Biophysics Journal"],["dc.bibliographiccitation.volume","44"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Oelkers, Marieelen"],["dc.contributor.author","Savic, Filip"],["dc.contributor.author","Awan, S."],["dc.contributor.author","Werz, Daniel B."],["dc.contributor.author","Geil, Burkhard"],["dc.contributor.author","Janshoff, Andreas"],["dc.date.accessioned","2018-11-07T09:55:36Z"],["dc.date.available","2018-11-07T09:55:36Z"],["dc.date.issued","2015"],["dc.format.extent","S244"],["dc.identifier.isi","000380001400772"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/36784"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.publisher.place","New york"],["dc.relation.eventlocation","Dresden, GERMANY"],["dc.relation.issn","1432-1017"],["dc.relation.issn","0175-7571"],["dc.title","Binding enthalpy driven accumulation of Lewis X in the membrane-membrane contact zone"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","145"],["dc.bibliographiccitation.lastpage","159"],["dc.bibliographiccitation.seriesnr","1860"],["dc.contributor.author","Witt, Hannes"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.editor","Fratti, Rutilio"],["dc.date.accessioned","2021-06-02T10:44:26Z"],["dc.date.available","2021-06-02T10:44:26Z"],["dc.date.issued","2019"],["dc.identifier.doi","10.1007/978-1-4939-8760-3_8"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/87037"],["dc.notes.intern","DOI-Import GROB-425"],["dc.publisher","Springer New York"],["dc.publisher.place","New York, NY"],["dc.relation.crisseries","Methods in Molecular Biology"],["dc.relation.eisbn","978-1-4939-8760-3"],["dc.relation.isbn","978-1-4939-8759-7"],["dc.relation.ispartof","Methods in Molecular Biology"],["dc.relation.ispartof","SNAREs : Methods and Protocols"],["dc.relation.ispartofseries","Methods in Molecular Biology; 1860"],["dc.title","Using Force Spectroscopy to Probe Coiled-Coil Assembly and Membrane Fusion"],["dc.type","book_chapter"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]