Jahn, Reinhard

[["dc.bibliographiccitation.firstpage","566"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Biochimica et Biophysica Acta (BBA) - Biomembranes"],["dc.bibliographiccitation.lastpage","578"],["dc.bibliographiccitation.volume","1860"],["dc.contributor.author","Xu, Yihui"],["dc.contributor.author","Kuhlmann, Jan"],["dc.contributor.author","Brennich, Martha"],["dc.contributor.author","Komorowski, Karlo"],["dc.contributor.author","Jahn, Reinhard"],["dc.contributor.author","Steinem, Claudia"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2018-01-17T13:00:13Z"],["dc.date.available","2018-01-17T13:00:13Z"],["dc.date.issued","2018"],["dc.description.abstract","SNAREs are known as an important family of proteins mediating vesicle fusion. For various biophysical studies, they have been reconstituted into supported single bilayers via proteoliposome adsorption and rupture. In this study we extended this method to the reconstitution of SNAREs into supported multilamellar lipid membranes, i.e. oriented multibilayer stacks, as an ideal model system for X-ray structure analysis (X-ray reflectivity and diffraction). The reconstitution was implemented through a pathway of proteomicelle, proteoliposome and multibilayer. To monitor the structural evolution in each step, we used small-angle X-ray scattering for the proteomicelles and proteoliposomes, followed by X-ray reflectivity and grazing-incidence small-angle scattering for the multibilayers. Results show that SNAREs can be successfully reconstituted into supported multibilayers, with high enough orientational alignment for the application of surface sensitive X-ray characterizations. Based on this protocol, we then investigated the effect of SNAREs on the structure and phase diagram of the lipid membranes. Beyond this application, this reconstitution protocol could also be useful for X-ray analysis of many further membrane proteins."],["dc.identifier.doi","10.1016/j.bbamem.2017.10.023"],["dc.identifier.pmid","29106973"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/11697"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","membrane biophysics"],["dc.title","Reconstitution of SNARE proteins into solid-supported lipid bilayer stacks and X-ray structure analysis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1200"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","1208"],["dc.bibliographiccitation.volume","98"],["dc.contributor.author","Castorph, Simon"],["dc.contributor.author","Riedel, Dietmar"],["dc.contributor.author","Arleth, Lise"],["dc.contributor.author","Sztucki, Michael"],["dc.contributor.author","Jahn, Reinhard"],["dc.contributor.author","Holt, Matthew"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-09-07T11:46:06Z"],["dc.date.available","2017-09-07T11:46:06Z"],["dc.date.issued","2010"],["dc.description.abstract","Synaptic vesicles (SVs) are small, membrane-bound organelles that are found in the synaptic terminal of neurons, and which are crucial in neurotransmission. After a rise in internal [Ca2+] during neuronal stimulation, SVs fuse with the plasma membrane releasing their neurotransmitter content, which then signals neighboring neurons. SVs are subsequently recycled and refilled with neurotransmitter for further rounds of release. Recently, tremendous progress has been made in elucidating the molecular composition of SVs, as well as putative protein-protein interactions. However, what is lacking is an empirical description of SV structure at the supramolecular level which is necessary to enable us to fully understand the processes of membrane fusion, retrieval, and recycling. Using small-angle x-ray scattering, we have directly investigated the size and structure of purified SVs. From this information, we deduced detailed size and density parameters for the protein layers responsible for SV function, as well as information about the lipid bilayer. To achieve a convincing model fit, a laterally anisotropic structure for the protein shell is needed, as a rotationally symmetric density profile does not explain the data. Not only does our model confirm many of the preexisting ideas concerning SV structure, but also for the first time, to our knowledge, it indicates structural refinements, such as the presence of protein microdomains."],["dc.identifier.doi","10.1016/j.bpj.2009.12.4278"],["dc.identifier.gro","3142938"],["dc.identifier.isi","000276582700012"],["dc.identifier.pmid","20371319"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/397"],["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","0006-3495"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","membrane biophysics"],["dc.title","Structure Parameters of Synaptic Vesicles Quantified by 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.bibliographiccitation.firstpage","1908"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","1920"],["dc.bibliographiccitation.volume","114"],["dc.contributor.author","Komorowski, Karlo"],["dc.contributor.author","Salditt, Annalena"],["dc.contributor.author","Xu, Yihui"],["dc.contributor.author","Yavuz, Halenur"],["dc.contributor.author","Brennich, Martha Elisabeth"],["dc.contributor.author","Jahn, Reinhard"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2020-03-03T08:17:24Z"],["dc.date.available","2020-03-03T08:17:24Z"],["dc.date.issued","2018"],["dc.description.abstract","We have studied the adhesion state (also denoted by docking state) of lipid vesicles as induced by the divalent ions Ca2+ or Mg2+ at well-controlled ion concentration, lipid composition, and charge density. The bilayer structure and the interbilayer distance in the docking state were analyzed by small-angle x-ray scattering. A strong adhesion state was observed for DOPC:DOPS vesicles, indicating like-charge attraction resulting from ion correlations. The observed interbilayer separations of ∼1.6 nm agree quantitatively with the predictions of electrostatics in the strong coupling regime. Although this phenomenon was observed when mixing anionic and zwitterionic (or neutral) lipids, pure anionic membranes (DOPS) with highest charge density σ resulted in a direct phase transition to a multilamellar state, which must be accompanied by rupture and fusion of vesicles. To extend the structural assay toward protein-controlled docking and fusion, we have characterized reconstituted N-ethylmaleimide-sensitive factor attachment protein receptors in controlled proteoliposome suspensions by small-angle x-ray scattering."],["dc.identifier.doi","10.1016/j.bpj.2018.02.040"],["dc.identifier.pmid","29694868"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63067"],["dc.language.iso","en"],["dc.relation.eissn","1542-0086"],["dc.relation.issn","0006-3495"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY-NC-ND 4.0"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","membrane biophysics"],["dc.title","Vesicle Adhesion and Fusion Studied by Small-Angle X-Ray Scattering"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","105004"],["dc.bibliographiccitation.journal","New Journal of Physics"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Ghosh, S. K."],["dc.contributor.author","Castorph, S."],["dc.contributor.author","Konovalov, O."],["dc.contributor.author","Jahn, R."],["dc.contributor.author","Holt, M."],["dc.contributor.author","Salditt, T."],["dc.date.accessioned","2017-09-07T11:45:15Z"],["dc.date.available","2017-09-07T11:45:15Z"],["dc.date.issued","2010"],["dc.description.abstract","The fusion of synaptic vesicles (SVs) with the plasma membrane in neurons is a crucial step in the release of neurotransmitters, which are responsible for carrying signals between nerve cells. While many of the molecular players involved in this fusion process have been identified, a precise molecular description of their roles in the process is still lacking. A case in point is the plasma membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2). Although PIP2 is known to be essential for vesicle fusion, its precise role in the process remains unclear. We have re-investigated the role of this lipid in membrane structure and function using the complementary experimental techniques of x-ray reflectivity, both on lipid monolayers at an air-water interface and bilayers on a solid support, and grazing incidence x-ray diffraction on lipid monolayers. These techniques provide unprecedented access to structural information at the molecular level, and detail the profound structural changes that occur in a membrane following PIP2 incorporation. Further, we also confirm and extend previous findings that the association of SVs with membranes is enhanced by PIP2 incorporation, and reveal the structural changes that underpin this phenomenon. Further, the association is further intensified by a physiologically relevant amount of Ca2+ ions in the subphase of the monolayer, as revealed by the increase in interfacial pressure seen with the lipid monolayer system. Finally, a theoretical calculation concerning the products arising from the fusion of these SVs with proteoliposomes is presented, with which we aim to illustrate the potential future uses of this system."],["dc.identifier.doi","10.1088/1367-2630/12/10/105004"],["dc.identifier.fs","572802"],["dc.identifier.gro","3142842"],["dc.identifier.isi","000284768300002"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/7194"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/290"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1367-2630"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","membrane biophysics"],["dc.subject.gro","neuro biophysics"],["dc.title","In vitro study of interaction of synaptic vesicles with lipid membranes"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1394"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","1402"],["dc.bibliographiccitation.volume","102"],["dc.contributor.author","Ghosh, Sajal Kumar"],["dc.contributor.author","Castorph, Simon"],["dc.contributor.author","Konovalov, Oleg"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","Jahn, Reinhard"],["dc.contributor.author","Holt, Matthew"],["dc.date.accessioned","2017-09-07T11:48:56Z"],["dc.date.available","2017-09-07T11:48:56Z"],["dc.date.issued","2012"],["dc.description.abstract","Synaptic vesicles (SVs) are small, membrane-bound organelles that are found in the synaptic terminal of neurons. Although tremendous progress has been made in understanding the protein machinery that drives fusion of SVs with the presynaptic membrane, little progress has been made in understanding changes in the membrane structure that accompany this process. We used lipid monolayers of defined composition to mimic biological membranes, which were probed by x-ray reflectivity and grazing incidence x-ray diffraction. These techniques allowed us to successfully monitor structural changes in the membranes at molecular level, both in response to injection of SVs in the subphase below the monolayer, as well as to physiological cues involved in neurotransmitter release, such as increases in the concentration of the membrane lipid PIP2, or addition of physiological levels of Ca2+. Such structural changes may well modulate vesicle fusion in vivo."],["dc.identifier.doi","10.1016/j.bpj.2012.01.006"],["dc.identifier.gro","3142562"],["dc.identifier.isi","000301907400018"],["dc.identifier.pmid","22455922"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8926"],["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","0006-3495"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","membrane biophysics"],["dc.subject.gro","neuro biophysics"],["dc.title","Measuring Ca2+-Induced Structural Changes in Lipid Monolayers: Implications for Synaptic Vesicle Exocytosis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]