Current-induced critical state in NbN thin-film structures (2008)
Ilin, Konstantin, Siegel, Michael, Engel, Andreas, Bartolf, Holger, Schilling, Andreas, Semenov, Alexey, ...
The temperature dependence of the critical current of NbN thin-film bridges was experimentally studied. At low temperatures we observed significant enhancement (up to two times at 4 K) of the...
Vortex-based single-photon response in nanostructured superconducting detectors (2008)
Semenov, Alexey, Haas, Philipp, Hübers, Heinz-Wilhelm, Ilin, Konstantin, Siegel, Michael, Kirste, Alexander, ...
In nanostructured superconducting films interaction of magnetic vortices with radiation quanta provides an additional mechanism of radiation detection. Below the Kosterlitz–Thouless topological...
Temperature- and field-dependence of critical currents in NbN microbridges (2008)
Engel, Andreas, Bartolf, Holger, Schilling, Andreas, Ilin, Konstantin, Siegel, Michael, Semenov, Alexei, ...
We report measurements of the critical current of nano- and micrometer-sized NbN bridges as a function of temperature and magnetic eld. The bridges were fabricated from 4 to 10 nm thick, sputtered...
Ultra-thin NbN films on Si: crystalline and superconducting properties (2008)
Ilin, Konstantin, Schneider, R, Gerthsen, D, Engel, Andreas, Bartolf, Holger, Schilling, Andreas, ...
We present results on superconducting and crystalline properties of NbN films with a thickness smaller than 10 nm. The films were deposited using reactive magnetron sputtering on heated silicon...
VirE2: A Unique ssDNA-Compacting Molecular Machine (2008)
Wilfried Grange, Myriam Duckely, Sudhir Husale, Susan Jacob, Andreas Engel, Martin Hegner
The translocation of single-stranded DNA (ssDNA) across membranes of two cells is a fundamental biological process occurring in both bacterial conjugation and Agrobacterium pathogenesis. Whereas...
Fluctuation theorem for entropy production during effusion of a relativistic ideal gas (2008)
CLEUREN, Bart, WILLAERT, Koen, ENGEL, Andreas, VAN DEN BROECK, Christian
The probability distribution of the entropy production for the effusion of a relativistic ideal gas is calculated explicitly. This result is then extended to include particle and antiparticle pair...
Prior-predictive value from fast growth simulations (2007)
Ahlers, Holger, Engel, Andreas
Building on a variant of the Jarzynski equation we propose a new method to numerically determine the prior-predictive value in a Bayesian inference problem. The method generalizes thermodynamic...
Computing the optimal protocol for finite-time processes in stochastic thermodynamics (2007)
Asking for the optimal protocol of an external control parameter that minimizes the mean work required to drive a nano-scale system from one equilibrium state to another in finite time, Schmiedl and...
Spectral Sensistivity and Spectral Resolution of Superconducting Single-Photon Detectors (2007)
Haas, Philipp Moritz, Semenov, Alexei, Hübers, Heinz-Wilhelm, Beyer, Jörn, Kirste, Alexander, Schurig, Thomas, ...
Single photon detectors based on meanders from 5-nm thin B1 niobium nitride nanostrips show moderate spectral resolution along with the spectral cut-off of the quantum efficiency occurring in the...
Energy resolution and sensitivity of a superconducting quantum detector (2007)
Semenov, Alexey, Haas, Philipp, Il'in, Konstantin, Hübers, Heinz-Wilhelm, Siegel, Michael, Engel, Andreas, ...
Single-photon detectors from thin niobium nitride nanostrips show moderate energy resolution along with the cut-off of the quantum efficiency in the near-infrared spectral range. To describe the...
Energy resolution and sensitivity of a superconducting quantum detector (2007)
Semenov, Alexey, Haas, Philipp, Ilin, Konstantin, Hübers, Heinz-Wilhelm, Siegel, Michael, Engel, Andreas, ...
Single-photon detectors from thin niobium nitride nanostrips show moderate energy resolution along with the cut-off of the quantum efficiency in the near-infrared spectral range. To describe the...
Cell-free production of G protein-coupled receptors for functional and structural studies (2007)
Klammt, Christian, Schwarz, Daniel, Eifler, Nora, Engel, Andreas, Piehler, Jacob, Haase, Winfried, ...
Engel, Andreas, Semenov, Alexey, Hübers, Heinz-Wilhelm, Il'in, Konstantin, Siegel, Michael
Superconducting thin films and micro- and nanostructured superconducting elements have enormous potential for applications in electronics and as highly sensitive detectors. We present recent studies...
Energieauflösung und spektrale Empfindlichkeit supraleitender Einzelphotonenzähler (2006)
Haas, Philipp Moritz, Semenov, Alexei, Hübers, Heinz-Wilhelm, Beyer, Jörn, Kirste, Alexander, Schurig, Thomas, ...
Hochempfindliche, ultraschnelle NbN-Einzelphotonenzähler, basierend auf der kurzzeitigen bias-stromunterstützten Ausbildung eines normal leitenden Bereichs (Hot-Spot) durch Photonenabsorption in...
Fluctuation effects in superconducting nanostrips (2006)
Engel, Andreas, Semenov, Alexey, Hübers, Heinz-Wilhelm, Il'in, Konstantin, Siegel, Michael
Superconducting fluctuations in long and narrow strips made from ultrathin NbN films, have been investigated. For large bias currents close to the critical current fluctuations led to localized,...
John, Thomas, Rannacher, Dirk, Engel, Andreas
We study the influence of surface tension on the shape of the conical miniscus built up by a magnetic fluid surrounding a current-carrying wire. Minimization of the total energy of the system leads...
Chemical ozone loss in the Arctic and Antarctic stratosphere (2006)
Tilmes, Simone, Müller, Rolf, Engel, Andreas, Rex, Markus, Russell III, James M.
An edited version of this paper was published by AGU. Copyright 2001 American Geophysical Union. To view the published open abstract, go to http://dx.doi.org/10.1029/2006GL026925
Parameter optimization for biometric fingerprint recognition using genetic algorithms (2006)
Tobias Scheidat, Andreas Engel, Claus Vielhauer
In this paper, we suggest an optimization approach for fingerprint authentication using genetic algorithms. Our application was planned so that it can be used without great effort for different...
Geiser, Andrew H., Sievert, Michael K., Guo, Lian-Wang, Grant, Jennifer E., Krebs, Mark P., Fotiadis, Dimitrios, ...
The mechanisms by which G-protein-coupled receptors (GPCRs) activate G-proteins are not well understood due to the lack of atomic structures of GPCRs in an active form or in GPCR/G-protein complexes....
Semenov, Alexey, Engel, Andreas, Hübers, Heinz-Wilhelm, Il´in, Konstantin, Siegel, Michael
We have studied supercurrent-assisted formation of the resistive state in nano-structured disordered superconducting Nb(N) films after absorption of a single optical to near-infrared photon. The...
Noise of a superconducting photon detector (2005)
Semenov, Alexey, Engel, Andreas, Hübers, Heinz-Wilhelm, Il´in, Konstantin, Siegel, Michael
We have studied electrical noise of photon detectors representing long and narrow superconducting strips. For large bias currents close to the critical current fluctuations lead to localized,...
Pretz, Monika G., Remigy, Hervé, Swaving, Jelto, Albers, Sonja V., Garrido, Victoria G., Chami, Mohamed, ...
The genome of the hyperthermophilic bacterium Thermotoga maritima contains the genes that encode core subunits of the protein translocase, a complex consisting of the molecular motor SecA and the...
The Economic Evaluation of E-Government: The Right Strategic Decision? (2005)
In view of the difficult budget situation, local communities now regard savings, rationalisation and increased efficiency as essential requirements for investments in e-government. Does this make the...
Structural insights into the secretin PulD and its trypsin-resistant core (2005)
Chami, Mohamed, Guilvout, Ingrid, Gregorini, Marco, W. Rémigy, Hervé, A. Müller, Shirley, Valerio, Marielle, ...
Current-noise superconducting bolometer for terahertz waves (2005)
Semenov, Alexey, Richter, Heiko, Hübers, Heinz-Wilhelm, Il´in, Konstantin, Siegel, Michael, Engel, Andreas
An advantage of superconducting detectors is a much lower noise in comparison to their semiconductor counterparts. We have studied the magnitude and spectrum of electric noise in thin superconducting...
Spectral performance of a single-photon detector (2005)
Semenov, Alexey, Engel, Andreas, Hübers, Heinz-WIlhelm, Il´in, Konstantin, Siegel, Michael
We have experimentally studied the supercurrent-assisted formation of the resistive state in nano-structured disordered superconducting Nb(N) films after absorption of a single optical to...
Noiseless limit of a ferrofluid ratchet (2004)
Becker, Volker, Engel, Andreas
The noiseless limit of a thermal ratchet device using ferrofluids is studied in detail. Contrary to previous claims it is proved that no directed transport can occur in this model in the absence of...
Semenov, Alexei, Engel, Andreas, Hübers, Heinz-Wilhelm, Ilin, Konstantin, Siegel, Michael
We have studied supercurrent-assisted formation of the resistive state in nano-structured Nb and NbN superconducting films after absorption of a single photon. In amorphous narrow NbN strips the...
Thermal ratchet effects in ferrofluids (2004)
Engel, Andreas, Reimann, Peter
Rotational Brownian motion of colloidal magnetic particles in ferrofluids under the influence of an oscillating external magnetic field is investigated. It is shown that for a suitable time...
Bucior, Iwona, Scheuring, Simon, Engel, Andreas, Burger, Max M.
© 2004 Bucior et al. This article is distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License. The definitive version was published in Journal...
Structure and assembly of the pseudopilin PulG (2004)
Köhler, Rolf, Schäfer, Karsten, Müller, Shirley, Vignon, Guillaume, Diederichs, Kay, Philippsen, Ansgar, ...
The pseudopilin PulG is one of several essential components of the type II pullulanase secretion machinery (the Pul secreton) of the Gram-negative bacterium Klebsiella oxytoca. The sequence of the...
On large deviation properties of Erdos-Renyi random graphs (2003)
Engel, Andreas, Monasson, Rémi, Hartmann, Alexander K.
We show that large deviation properties of Erd\"os-R\'enyi random graphs can be derived from the free energy of the $q$-state Potts model of statistical mechanics. More precisely the Legendre...
Double Rosensweig instability in a ferrofluid sandwich structure (2003)
Rannacher, Dirk, Engel, Andreas
We consider a horizontal ferrofluid layer sandwiched between two layers of immiscible non-magnetic fluids. In a sufficiently strong vertical magnetic field the flat interfaces between magnetic and...
Local amplitude equation from non-local dynamics (2003)
Friedrichs, Rene, Engel, Andreas
We derive a closed equation for the shape of the free surface of a magnetic fluid subject to an external magnetic field. The equation is strongly non-local due to the long range character of the...
Observing membrane protein diffusion at subnanometer resolution. (2003)
Muller, Daniel J, Engel, Andreas, Matthey, Ulrich, Meier, Thomas, Dimroth, Peter, Suda, Kitaru
Single sodium-driven rotors from a bacterial ATP synthase were embedded into a lipid membrane and observed in buffer solution at subnanometer resolution using atomic force microscopy (AFM)....
Determining molecular forces that stabilize human aquaporin-1. (2003)
Moller, Clemens, Fotiadis, Dimitrios, Suda, Kitaru, Engel, Andreas, Kessler, Max, Muller, Daniel J
Atomic force microscopy (AFM) was used to measure the forces stabilizing human aquaporin-1 (hAQP1), a tetrameric transmembrane protein that forms highly specific water channels. To this end, the AFM...
Ferrofluids as thermal ratchets (2002)
Engel, Andreas, Mueller, Hanns Walter, Reimann, Peter, Jung, Achim
Colloidal suspensions of ferromagnetic nano-particles, so-called ferrofluids, are shown to be suitable systems to demonstrate and investigate thermal ratchet behavior: By rectifying thermal...
Phase Transition in Multiprocessor Scheduling (2002)
Bauke, Heiko, Mertens, Stephan, Engel, Andreas
The problem of distributing the workload on a parallel computer to minimize the overall runtime is known as Multiprocessor Scheduling Problem. It is NP-hard, but like many other NP-hard problems, the...
Engel, Andreas, Trodahl, H. J.
Linear resistances and $IV$-characteristics have been measured over a wide range in the parameter space of the mixed phase of multilayered a-TaGe/Ge films. Three films with varying interlayer...
Jamming transitions and avalanches in the game of Dots-and-Boxes (2002)
Metzler, Richard, Engel, Andreas
We study the game of Dots-and-Boxes from a statistical point of view. The early game can be treated as a case of Random Sequential Adsorption, with a jamming transition that marks the beginning of...
Philippsen, Ansgar, Im, Wonpil, Engel, Andreas, Schirmer, Tilman, Roux, Benoit, Müller, Daniel J.
The atomic force microscope (AFM) was used to image native OmpF porin and to detect the electrostatic potential generated by the protein. To this end the OmpF porin trimers from Escherichia coli was...
Conformational changes in surface structures of isolated connexin 26 gap junctions (2002)
Müller, Daniel J., Hand, Galen M., Engel, Andreas, Sosinsky, Gina E.
Gap junction channels mediate communication between adjacent cells. Using atomic force microscopy (AFM), we have imaged conformational changes of the cytoplasmic and extracellular surfaces of native...
Imaging and manipulation of biological structures with the AFM (2002)
Fotiadis, Dimitrios, Scheuring, Simon, Müller, Shirley A., Engel, Andreas, Müller, Daniel J.
Many biologists have dreamt of physically touching and manipulating the biomolecules they were investigating. With the invention of the atomic force microscope (AFM), this dream has come true. Here,...
Identification and structure of a putative Ca2+-binding domain at the C terminus of AQP1 (2002)
Fotiadis, Dimitrios, Suda, Kitaru, Tittmann, Peter, Jeno, Paul, Philippsen, Ansgar, Müller, Daniel J., ...
um in translocation of AQP1 in cholangiocytes from intracellular vesicles to the plasma membrane and in triggering its fusion is discussed. Functional studies are now required to identify the...
Multilayer neural networks with extensively many hidden units (2001)
Rosen-Zvi, Michal, Engel, Andreas, Kanter, Ido
The information processing abilities of a multilayer neural network with a number of hidden units scaling as the input dimension are studied using statistical mechanics methods. The mapping from the...
Pattern and wavenumber selection in ferrofluids (2001)
Friedrichs, René, Engel, Andreas
The formation of patterns of peaks on the free surface of a ferrofluid subject to a magnetic field normal to the undisturbed interface is investigated theoretically. The relative stability of ridge,...
SecYEG assembles into a tetramer to form the active protein translocation channel (2000)
Manting, Erik H., Does, Chris Van Der, Remigy, Hervé, Engel, Andreas, Driessen, Arnold J.M.
Translocase mediates preprotein translocation across the Escherichia coli inner membrane. It consists of the SecYEG integral membrane protein complex and the peripheral ATPase SecA. Here we show by...
Dewetting dynamics of helium films on cesiated surfaces (2000)
Reinelt, Dietmar, Engel, Andreas, Klier, Jürgen
The nonwetting of liquid 4He on Cs below = 2 K is now well established. However, there exist discrepancies between the measured contact angles and hysteresis at the phase transition of various...
Dynamics of a Single Peak of the Rosensweig Instability in a Magnetic Fluid (1999)
Lange, Adrian, Langer, Heinz, Engel, Andreas
To describe the dynamics of a single peak of the Rosensweig instability a model is proposed which approximates the peak by a half-ellipsoid atop a layer of magnetic fluid. The resulting nonlinear...
Dissipation in ferrofluids: Mesoscopic versus hydrodynamic theory (1999)
Müller, Hanns Walter, Engel, Andreas
Part of the field dependent dissipation in ferrofluids occurs due to the rotational motion of the ferromagnetic grains relative to the viscous flow of the carrier fluid. The classical theoretical...
Correlation of internal representations in feed-forward neural networks (1996)
Feed-forward multilayer neural networks implementing random input-output mappings develop characteristic correlations between the activity of their hidden nodes which are important for the...
Engel, Andreas, Tanaka, Eiji I., Maruyama, Tomoyuki, Ono, Akira, Horiuchi, Hisashi
Delta degrees of freedom are introduced into antisymmetrized molecular dynamics (AMD). This is done by increasing the number of basic states in the AMD wave function, introducing a Skyrme-type...
Proton inelastic scattering to continuum studied with antisymmetrized molecular dynamics (1995)
Tanaka, Eiji I., Ono, Akira, Horiuchi, Hisashi, Maruyama, Tomoyuki, Engel, Andreas
Intermediate energy (p,p$'$x) reaction is studied with antisymmetrized molecular dynamics (AMD) in the cases of $^{58}$Ni target with $E_p = 120$ MeV and $^{12}$C target with $E_p = $ 200 and 90 MeV....
Sozialwissenschaftliche Datenanalyse (1995)
Engel, Andreas, Möhring, Michael, Troitzsch, Klaus G.
Der Einsatz von Computern hat in den vergangenen Jahrzehnten die Arbeitsweise von Sozialwissenschaftlern nachhaltig verändert. Es ist wohl nicht übertrieben zu behaupten, daß die Verbreitung und...
Statistische Mechanik von Netzwerken formaler Neuronen. (1990)
Berlin, Humboldt-Univ., Diss. B, 1990 (Nicht f.d. Austausch).
Reaktions-Diffusions-Prozesse in stochastischen Feldern. (1985)
Berlin, Humboldt-Univ., Diss., 1985 (Nicht f.d. Austausch).
Self-assembly of single and closely spaced nucleosome core particles (1980)
Noll, Markus, Zimmer, Steven, Engel, Andreas, Dubochet, Jacques
Self-assembly of DNA with the four core histones but in the absence of H1 generates nucleosome core particles which are spaced randomly over large distances. Closely spaced core particles, however,...
Übertragungseigenschaften spezieller holographischer Filter. (1973)
Diss. Naturwiss. Bern 1973. (KA).
Mitochondrial Lon of Saccharomyces cerevisiae is a ring-shaped protease with seven flexible subunits
Stahlberg, Henning, Kutejová, Eva, Suda, Kitaru, Wolpensinger, Bettina, Lustig, Ariel, Schatz, Gottfried, ...
Lon (or La) is a soluble, homooligomeric ATP-dependent protease. Mass determination and cryoelectron microscopy of pure mitochondrial Lon from Saccharomyces cerevisiae identify Lon as a flexible...
Secretin PulD: Association with pilot PulS, structure, and ion-conducting channel formation
Nouwen, Nico, Ranson, Neil, Saibil, Helen, Wolpensinger, Bettina, Engel, Andreas, Ghazi, Alexandre, ...
The outer membrane protein PulD (secretin) of Klebsiella oxytoca is required for transport of pullulanase across this membrane. We have purified a multimeric PulD complex from an Escherichia coli...
Controlled unzipping of a bacterial surface layer with atomic force microscopy
Müller, Daniel J., Baumeister, Wolfgang, Engel, Andreas
We have combined high-resolution atomic force microscopy (AFM) imaging and force spectroscopy to gain insight into the interaction forces between the individual protomers of the hexagonally packed...
Conformational changes in surface structures of isolated connexin 26 gap junctions
Müller, Daniel J., Hand, Galen M., Engel, Andreas, Sosinsky, Gina E.
Gap junction channels mediate communication between adjacent cells. Using atomic force microscopy (AFM), we have imaged conformational changes of the cytoplasmic and extracellular surfaces of native...
The McrBC restriction endonuclease assembles into a ring structure in the presence of G nucleotides
Panne, Daniel, Müller, Shirley A., Wirtz, Sabine, Engel, Andreas, Bickle, Thomas A.
McrBC from Escherichia coli K-12 is a restriction enzyme that belongs to the family of AAA+ proteins and cuts DNA containing modified cytosines. Two proteins are expressed from the mcrB gene: a...
High-resolution AFM topographs of Rubrivivax gelatinosus light-harvesting complex LH2
Scheuring, Simon, Reiss-Husson, Francoise, Engel, Andreas, Rigaud, Jean-Louis, Ranck, Jean-Luc
Light-harvesting complexes 2 (LH2) are the accessory antenna proteins in the bacterial photosynthetic apparatus and are built up of αβ-heterodimers containing three bacteriochlorophylls and one...
SecYEG assembles into a tetramer to form the active protein translocation channel
Manting, Erik H., Van Der Does, Chris, Remigy, Hervé, Engel, Andreas, Driessen, Arnold J.M.
Translocase mediates preprotein translocation across the Escherichia coli inner membrane. It consists of the SecYEG integral membrane protein complex and the peripheral ATPase SecA. Here we show by...
Molecular architecture of photosynthetic membranes in Rhodobacter sphaeroides: the role of PufX
Siebert, C Alistair, Qian, Pu, Fotiadis, Dimitrios, Engel, Andreas, Hunter, C Neil, Bullough, Per A
The effects of the PufX polypeptide on membrane architecture were investigated by comparing the composition and structures of photosynthetic membranes from PufX+ and PufX− strains of Rhodobacter...
Domain structure of secretin PulD revealed by limited proteolysis and electron microscopy
Nouwen, Nico, Stahlberg, Henning, Pugsley, Anthony P., Engel, Andreas
Secretins, a superfamily of multimeric outer membrane proteins, mediate the transport of large macromolecules across the outer membrane of Gram-negative bacteria. Limited proteolysis of secretin PulD...
Stoichiometric model of the photosynthetic unit of Ectothiorhodospira halochloris
Engelhardt, Harald, Engel, Andreas, Baumeister, Wolfgang
A stoichiometric model of the photosynthetic unit of Ectothiorhodospira halochloris has been obtained by means of scanning transmission electron microscope mass determination and mass mapping in...
Bacterial Na+-ATP synthase has an undecameric rotor
Stahlberg, Henning, Müller, Daniel J., Suda, Kitaru, Fotiadis, Dimitrios, Engel, Andreas, Meier, Thomas, ...
Synthesis of adenosine triphosphate (ATP) by the F1F0 ATP synthase involves a membrane-embedded rotary engine, the F0 domain, which drives the extra-membranous catalytic F1 domain. The F0 domain...
The 3.7 Å projection map of the glycerol facilitator GlpF: a variant of the aquaporin tetramer
Braun, Thomas, Philippsen, Ansgar, Wirtz, Sabine, Borgnia, Mario J., Agre, Peter, Kühlbrandt, Werner, ...
GlpF, the glycerol facilitator protein of Escherichia coli, is an archetypal member of the aquaporin superfamily. To assess its structure, recombinant histidine-tagged protein was overexpressed,...
Electron and atomic force microscopy of the trimeric ammonium transporter AmtB
Conroy, Matthew J, Jamieson, Stuart J, Blakey, Daniel, Kaufmann, Thomas, Engel, Andreas, Fotiadis, Dimitrios, ...
Escherichia coli AmtB is an archetypal member of the ammonium transporter (Amt) family, a family of proteins that are conserved in all domains of life. Reconstitution of AmtB in the presence of...
Philippsen, Ansgar, Im, Wonpil, Engel, Andreas, Schirmer, Tilman, Roux, Benoit, Müller, Daniel J
The atomic force microscope (AFM) was used to image native OmpF porin and to detect the electrostatic potential generated by the protein. To this end the OmpF porin trimers from Escherichia coli was...
Rhodopsin Signaling and Organization in Heterozygote Rhodopsin Knockout Mice*S
Liang, Yan, Fotiadis, Dimitrios, Maeda, Tadao, Maeda, Akiko, Modzelewska, Anna, Filipek, Slawomir, ...
Rhodopsin (Rho) resides within internal membrane structures called disc membranes that are found in the rod outer segments (ROS) of photoreceptors in the retina. Rho expression is essential for...
The supramolecular structure of the GPCR rhodopsin in solution and native disc membranes
Suda, Kitaru, Filipek, Slawomir, Palczewski, Krzysztof, Engel, Andreas, Fotiadis, Dimitrios
Rhodopsin, the prototypical G-protein-coupled receptor, which is densely packed in the disc membranes of rod outer segments, was proposed to function as a monomer. However, a growing body of evidence...
Functional Characterization of Rhodopsin Monomers and Dimers in Detergents*S
Jastrzebska, Beata, Maeda, Tadao, Zhu, Li, Fotiadis, Dimitrios, Filipek, Slawomir, Engel, Andreas, ...
Rhodopsin (Rho) is a G protein-coupled receptor that initiates phototransduction in rod photoreceptors. High expression levels of Rho in the disc membranes of rod outer segments and the propensity of...
Organization of the G Protein-coupled Receptors Rhodopsin and Opsin in Native Membranes*
Liang, Yan, Fotiadis, Dimitrios, Filipek, Sławomir, Saperstein, David A., Palczewski, Krzysztof, Engel, Andreas
G protein-coupled receptors (GPCRs), which constitute the largest and structurally best conserved family of signaling molecules, are involved in virtually all physiological processes. Crystal...
The G protein-coupled receptor rhodopsin in the native membrane
Fotiadis, Dimitrios, Liang, Yan, Filipek, Slawomir, Saperstein, David A., Engel, Andreas, Palczewski, Krzysztof
The higher-order structure of G protein-coupled receptors (GPCRs) in membranes may involve dimerization and formation of even larger oligomeric complexes. Here, we have investigated the organization...
Mitochondrial Lon of Saccharomyces cerevisiae is a ring-shaped protease with seven flexible subunits
Stahlberg, Henning, Kutejová, Eva, Suda, Kitaru, Wolpensinger, Bettina, Lustig, Ariel, Schatz, Gottfried, ...
Lon (or La) is a soluble, homooligomeric ATP-dependent protease. Mass determination and cryoelectron microscopy of pure mitochondrial Lon from Saccharomyces cerevisiae identify Lon as a flexible...
Secretin PulD: Association with pilot PulS, structure, and ion-conducting channel formation
Nouwen, Nico, Ranson, Neil, Saibil, Helen, Wolpensinger, Bettina, Engel, Andreas, Ghazi, Alexandre, ...
The outer membrane protein PulD (secretin) of Klebsiella oxytoca is required for transport of pullulanase across this membrane. We have purified a multimeric PulD complex from an Escherichia coli...
Controlled unzipping of a bacterial surface layer with atomic force microscopy
Müller, Daniel J., Baumeister, Wolfgang, Engel, Andreas
We have combined high-resolution atomic force microscopy (AFM) imaging and force spectroscopy to gain insight into the interaction forces between the individual protomers of the hexagonally packed...
Conformational changes in surface structures of isolated connexin 26 gap junctions
Müller, Daniel J., Hand, Galen M., Engel, Andreas, Sosinsky, Gina E.
Gap junction channels mediate communication between adjacent cells. Using atomic force microscopy (AFM), we have imaged conformational changes of the cytoplasmic and extracellular surfaces of native...
The McrBC restriction endonuclease assembles into a ring structure in the presence of G nucleotides
Panne, Daniel, Müller, Shirley A., Wirtz, Sabine, Engel, Andreas, Bickle, Thomas A.
McrBC from Escherichia coli K-12 is a restriction enzyme that belongs to the family of AAA+ proteins and cuts DNA containing modified cytosines. Two proteins are expressed from the mcrB gene: a...
High-resolution AFM topographs of Rubrivivax gelatinosus light-harvesting complex LH2
Scheuring, Simon, Reiss-Husson, Francoise, Engel, Andreas, Rigaud, Jean-Louis, Ranck, Jean-Luc
Light-harvesting complexes 2 (LH2) are the accessory antenna proteins in the bacterial photosynthetic apparatus and are built up of αβ-heterodimers containing three bacteriochlorophylls and one...
SecYEG assembles into a tetramer to form the active protein translocation channel
Manting, Erik H., Van Der Does, Chris, Remigy, Hervé, Engel, Andreas, Driessen, Arnold J.M.
Translocase mediates preprotein translocation across the Escherichia coli inner membrane. It consists of the SecYEG integral membrane protein complex and the peripheral ATPase SecA. Here we show by...
Molecular architecture of photosynthetic membranes in Rhodobacter sphaeroides: the role of PufX
Siebert, C Alistair, Qian, Pu, Fotiadis, Dimitrios, Engel, Andreas, Hunter, C Neil, Bullough, Per A
The effects of the PufX polypeptide on membrane architecture were investigated by comparing the composition and structures of photosynthetic membranes from PufX+ and PufX− strains of Rhodobacter...
Domain structure of secretin PulD revealed by limited proteolysis and electron microscopy
Nouwen, Nico, Stahlberg, Henning, Pugsley, Anthony P., Engel, Andreas
Secretins, a superfamily of multimeric outer membrane proteins, mediate the transport of large macromolecules across the outer membrane of Gram-negative bacteria. Limited proteolysis of secretin PulD...
Stoichiometric model of the photosynthetic unit of Ectothiorhodospira halochloris
Engelhardt, Harald, Engel, Andreas, Baumeister, Wolfgang
A stoichiometric model of the photosynthetic unit of Ectothiorhodospira halochloris has been obtained by means of scanning transmission electron microscope mass determination and mass mapping in...
Bacterial Na+-ATP synthase has an undecameric rotor
Stahlberg, Henning, Müller, Daniel J., Suda, Kitaru, Fotiadis, Dimitrios, Engel, Andreas, Meier, Thomas, ...
Synthesis of adenosine triphosphate (ATP) by the F1F0 ATP synthase involves a membrane-embedded rotary engine, the F0 domain, which drives the extra-membranous catalytic F1 domain. The F0 domain...
The 3.7 Å projection map of the glycerol facilitator GlpF: a variant of the aquaporin tetramer
Braun, Thomas, Philippsen, Ansgar, Wirtz, Sabine, Borgnia, Mario J., Agre, Peter, Kühlbrandt, Werner, ...
GlpF, the glycerol facilitator protein of Escherichia coli, is an archetypal member of the aquaporin superfamily. To assess its structure, recombinant histidine-tagged protein was overexpressed,...
Electron and atomic force microscopy of the trimeric ammonium transporter AmtB
Conroy, Matthew J, Jamieson, Stuart J, Blakey, Daniel, Kaufmann, Thomas, Engel, Andreas, Fotiadis, Dimitrios, ...
Escherichia coli AmtB is an archetypal member of the ammonium transporter (Amt) family, a family of proteins that are conserved in all domains of life. Reconstitution of AmtB in the presence of...
Philippsen, Ansgar, Im, Wonpil, Engel, Andreas, Schirmer, Tilman, Roux, Benoit, Müller, Daniel J
The atomic force microscope (AFM) was used to image native OmpF porin and to detect the electrostatic potential generated by the protein. To this end the OmpF porin trimers from Escherichia coli was...
A Novel Method for Detergent Concentration Determination
Kaufmann, Thomas C., Engel, Andreas, Rémigy, Hervé-W.
A fast and precise method for detergent concentration determination is presented. (Patent applications for the method described here have been submitted (EP05011904 and US60/702,261). Depending on...
Conformational Change of Bacteriorhodopsin Quantitatively Monitored by Microcantilever Sensors
Braun, Thomas, Backmann, Natalija, Vögtli, Manuel, Bietsch, Alexander, Engel, Andreas, Lang, Hans-Peter, ...
Bacteriorhodopsin proteoliposomes were used as a model system to explore the applicability of micromechanical cantilever arrays to detect conformational changes in membrane protein patches. The three...
Cytotoxin ClyA from Escherichia coli assembles to a 13-meric pore independent of its redox-state
Eifler, Nora, Vetsch, Michael, Gregorini, Marco, Ringler, Philippe, Chami, Mohamed, Philippsen, Ansgar, ...
ClyA is a pore-forming toxin from virulent Escherichia coli and Salmonella enterica strains. Here, we show that the intrinsic hemolytic activity of ClyA is independent of its redox state, and that...
Guilvout, Ingrid, Chami, Mohamed, Engel, Andreas, Pugsley, Anthony P, Bayan, Nicolas
Dodecamerization and insertion of the outer membrane secretin PulD is entirely determined by the C-terminal half of the polypeptide (PulD-CS). In the absence of its cognate chaperone PulS, PulD-CS...
VirE2: A Unique ssDNA-Compacting Molecular Machine
Grange, Wilfried, Duckely, Myriam, Husale, Sudhir, Jacob, Susan, Engel, Andreas, Hegner, Martin
The translocation of single-stranded DNA (ssDNA) across membranes of two cells is a fundamental biological process occurring in both bacterial conjugation and Agrobacterium pathogenesis. Whereas...
Bucior, Iwona, Scheuring, Simon, Engel, Andreas, Burger, Max M.
The adhesion force and specificity in the first experimental evidence for cell–cell recognition in the animal kingdom were assigned to marine sponge cell surface proteoglycans. However, the...
Geiser, Andrew H., Sievert, Michael K., Guo, Lian-Wang, Grant, Jennifer E., Krebs, Mark P., Fotiadis, Dimitrios, ...
The mechanisms by which G-protein-coupled receptors (GPCRs) activate G-proteins are not well understood due to the lack of atomic structures of GPCRs in an active form or in GPCR/G-protein complexes....
Aquaporin water channels – from atomic structure to clinical medicine
Agre, Peter, King, Landon S, Yasui, Masato, Guggino, Wm B, Ottersen, Ole Petter, Fujiyoshi, Yoshinori, ...
The water permeability of biological membranes has been a longstanding problem in physiology, but the proteins responsible for this remained unknown until discovery of the aquaporin 1 (AQP1) water...
Hölzl, Harald, Kapelari, Barbara, Kellermann, Josef, Seemüller, Erika, Sümegi, Máté, Udvardy, Andor, ...
Drosophila melanogaster embryos are a source for homogeneous and stable 26S proteasomes suitable for structural studies. For biochemical characterization, purified 26S proteasomes were resolved by...
YscU recognizes translocators as export substrates of the Yersinia injectisome
Sorg, Isabel, Wagner, Stefanie, Amstutz, Marlise, Müller, Shirley A, Broz, Petr, Lussi, Yvonne, ...
YscU is an essential component of the export apparatus of the Yersinia injectisome. It consists of an N-terminal transmembrane domain and a long cytoplasmic C-terminal domain, which undergoes...