Latest documents http://publikationen.stub.uni-frankfurt.de/index/index/ Sat, 06 Jul 2013 13:04:36 +0200 Sat, 06 Jul 2013 13:04:36 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/30083 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/30083 Fri, 07 Jun 2013 13:04:36 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/30082 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/30082 Fri, 07 Jun 2013 12:59:51 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29965 Im Bemühen um ein internationales Forum für germanistische Studien erschien im September 2007 in Ústí nad Labem/Aussig die neue Zeitschrift 'Aussiger Beiträge'. Die erste Ausgabe ('Aussiger Beiträge' 1/2007) verwirklichte das Konzept langjähriger Überlegungen und war der erste Schritt zur Profilierung einer germanistischen Schriftenreihe mit sowohl innovativen wissenschaftlichen als auch lehrpraktischen Bezügen im Bereich der Literatur, Linguistik, Didaktik des Deutschen als Fremdsprache und Kulturgeschichte. Sie ist in erster Linie von dem Gedanken getragen, eine internationale Fachzeitschrift mit hohem Gebrauchswert zu schaffen und möchte – gewissermaßen aus der Mitte eines bewegten Europas heraus – als Periodikum neue Impulse zu anstehenden Debatten und Diskussionen geben. In diesem Sinne wenden sich die 'Aussiger Beiträge' an eine breitere Schicht von Lesern: Linguisten, Literaturwissenschaftler, Sprachdidaktiker sind ebenso angesprochen wie aufgeschlossene Leser mit Interessen für Sprache, Kultur und Geschichte. Für die Beiträge in deutscher Sprache bildet der gemeinsame deutsch-österreichisch-tschechische Kulturraum einen Rahmen, wobei sowohl den Fragestellungen der "klassischen" Auslandsgermanistik als auch viel versprechenden innovativen Forschungsinteressen ein Platz eingeräumt und auf einen Dialog von jüngeren und älteren Generationen gebaut wird. In diesem umfassenden Sinne wurde zunächst eine erste Nummer der 'Aussiger Beiträge' (1/2007) konzipiert, die alle germanistischen Bereiche (Literatur, Linguistik, Didaktik und Kulturgeschichte) berücksichtigte. Für die weitere Positionierung der Zeitschrift erwies es sich als sinnvoll, das Profil der 'Aussiger Beiträge' noch deutlicher zu akzentuieren. So erscheint die Zeitschrift seit 2008 in fortlaufender Folge abwechselnd als "literarische" oder "linguistisch-didaktische" Ausgabe unter dezidiert thematischem Schwerpunkt. Seit 2008 werden alle Beiträge von unabhängigen GutachterInnen anonym beurteilt. Auf Grund ihrer Empfehlung entscheidet der Redaktionsrat über die Annahme eines Beitrags (mit Zusammenfassung in deutscher und englischer Sprache). Außer wissenschaftlichen Beiträgen werden ebenfalls Rezensionen wichtiger germanistischer Publikationen sowie relevante Tagungs- und Projektberichte abgedruckt. periodical http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29965 Fri, 17 May 2013 14:41:15 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29871 periodical http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29871 Mon, 13 May 2013 10:46:32 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29837 article http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29837 Fri, 19 Apr 2013 12:25:02 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29823 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29823 Fri, 19 Apr 2013 10:51:50 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29736 The Center of Excellence SAFE – “Sustainable Architecture for Finance in Europe” – is a cooperation of the Center for Financial Studies and Goethe University Frankfurt. It is funded by the LOEWE initiative of the State of Hessen (Landes-Offensive zur Entwicklung wissenschaftlich-ökonomischer Exzellenz). SAFE brings together more than 40 professors and just as many junior researchers who are all dedicated to conducting research in support of a sustainable financial architecture. The Center has two main pillars: excellent research on all important topics related to finance; and policy advice, including the dissemination of relevant research findings to European decision makers from the realms of politics, regulation and administration. In order to promote a fruitful exchange with interested parties from politics, academia, business and the media, SAFE issues a newsletter on a quarterly basis. This aims to provide an overview of the Center‘s ongoing research and policy activities. The SAFE Newsletter succeeds the House of Finance Newsletter, which was published between 2009 and 2012. SAFE is based at Goethe University’s House of Finance however extends beyond by drawing on scholars from other parts of Goethe University as well as from fellow research institutions. The Center builds on the reputation of the House of Finance institutions, serving as an interdisciplinary think tank on the issue of finance. periodical http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29736 Mon, 15 Apr 2013 12:48:38 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29788 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29788 Sun, 14 Apr 2013 13:29:27 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29787 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29787 Sun, 14 Apr 2013 13:28:45 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29789 Die Zeitschrift Kochia wird von der Gesellschaft zur Erforschung der Flora Deutschlands (GEFD) herausgegeben; sie ist dem Botaniker Wilhelm Daniel Joseph Koch gewidmet und erscheint einmal jährlich, in der Regel im vierten Quartal. Nach Ablauf einer Frist von fünf Jahren wird der Inhalt der Kochia-Bände auf den Internet-Seiten der Gesellschaft sowie auf vifabioDOC online frei zugängig gemacht. periodical http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29789 Sun, 14 Apr 2013 13:27:54 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29780 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29780 Fri, 12 Apr 2013 15:33:19 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29777 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29777 Fri, 12 Apr 2013 15:10:18 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29775 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29775 Fri, 12 Apr 2013 14:51:00 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29764 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29764 Thu, 11 Apr 2013 13:40:13 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29763 article http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29763 Thu, 11 Apr 2013 10:50:52 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29760 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29760 Thu, 11 Apr 2013 09:51:46 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29732 The universal biological energy currency adenosine triphosphate (ATP) is synthesized by the F1Fo-ATP synthase in most living organisms. The overall structure and function of F-type ATPases is conserved in the different organisms. The F1Fo-ATP synthase consist of two domains; the soluble F1 complex has the subunit stoichiometry α3β3γδε and the membrane embedded Fo complex consists of subunits ab2c10-15 in its simplest form found in bacteria. F1 and Fo both function as reversible rotary motors that are connected by a central stalk (γε) and a peripheral stalk (b2δ). For ATP synthesis, the electrochemical energy formed by a proton or sodium ion gradient is required. The ion translocation across the Fo subcomplex induces torque in the motor part of the enzyme (cnγε), which causes conformational changes in the α3β3 domain leading to ATP synthesis from ADP and inorganic phosphate (Pi) catalyzed in the β-subunits. ATP hydrolysis causes a reverse torque in the Fo subcomplex triggering uphill ion translocation from cytoplasm to periplasm, and the enzyme functions as an ion pump. The ATP synthesis mechanism is well understood, since several high-resolution structures of F1 are available. In contrast, the ion translocation mechanism across the membrane, mediated by the Fo subcomplex, is not understood in its structural detail. Subunit a and the c-ring form an ion pathway, but subunit b is needed to form an active ion translocation pathway in both H+- and Na+-dependent systems. Several high-resolution structures of c-rings have provided insights in the ion translocation mechanism. The different ion translocation models based on biochemical, biophysical and structural analysis are in agreement in the fact that ions are translocated through a periplasmic ion access pathway in subunit a to the middle of the membrane and there to the binding site of a c-subunit. After almost a whole rotation of the c-ring the ion returns into the a-c interface, where it can be released to the cytoplasm. In the different models the cytoplasmic access pathway has been proposed to be located in subunit a, at the a-c interface or within the c-ring. The driving force of torque generation has been proposed to be the pH gradient or membrane potential. Several biochemical studies show that a conserved arginine in helix four of subunit a (R226 in Ilyobacter tartaricus or R210 in Escherichia coli)plays a critical role in the ion translocation. The arginine has been proposed to function as an electrostatic separator between the cytoplasmic and periplasmic pathways and as a mediator of the ion exchange into the c-ring ion-binding site. Structural data of a related enzyme (V1Vo-ATPase from Thermus thermophilus) has provided insight into the helical arrangement of the ion translocating subunits I and Lring (related to subunit a and the c-ring). These structures indicated a small interface between subunit I and the L-ring, and two four-helix bundles in the N-terminal domain of subunit I were proposed to build the periplasmic and cytoplasmic ion pathways. To comprehend the ion-translocation and torque generation mechanism in F1Fo-ATP synthase, structural data of an intact a-c complex is needed. The goal of this work was to obtain structural data of subunit a, most preferably in a complex with the c-ring or additionally with subunit b. Therefore, a new purification procedure for the I. tartaricus Fo-subcomplex, heterologously expressed in E. coli cells, was established. The purified Fo was characterized biochemically and by Laserinduced liquid bead ion desorption mass spectrometry (LILBID-MS). These analyses showed that pure and completely assembled Fo containing all its subunits in the correct stoichiometry (ab2c11) was obtained. The purified Fo complex was stable at 4°C for several months and at room temperature in the presence of lipids for several weeks. A lipid analysis was performed by thin-layer chromatography (TLC) to investigate the qualitative lipid composition of I. tartaricus whole lipid extract and various I. tartaricus F1Fo isolates. The whole lipid extract contained PC, PG and PE lipids and probably cardiolipin. PC, PG and PE lipids were bound to wild type I. tartaricus F1Fo, whereas recombinant I. tartaricus F1Fo did not have any bound lipids, but was able to bind the synthetic lipids POPC and POPG if they were provided during the purification. For subsequent structural studies the purified Fo was subjected to two-dimensional (2D) crystallization trials. Vesicles and sheets tightly packed with protein and crystals with a rare plane group for I. tartaricus c11 (p121) were obtained. The c-ring was visible in the CCD images, and immunogold-labeling revealed the presence of the His-tagged a-subunit in the reconstituted vesicles. Furthermore, atomic force microscopy (AFM) imaging showed protein densities next to the c-rings, which protruded less from the membrane (0.4±0.1 nm) than the c-ring (0.7±0.1 nm). These protein densities presumably belonged to subunit a. Cryo-electronmicroscopy (cryo-EM) was used to collect data of the p121 crystals and a merged projection density map was calculated to 7.0 Å resolution. The unit cell of the crystals (81 × 252 Å) contained two asymmetric units with three c-rings in each and next to the c11-rings new prominent densities were visible. In each extra density up to 7 transmembrane helices were visible, belonging to the stator subunit a and/or subunit b. To elucidate whether there are conserved elements in the three extra densities non-crystallographic averaging was applied using a single-particle approach. Six possible arrangements for the c-rings and the extra densities were identified and used for the averaging. The extra densities were enhanced only in one of the possible arrangements. The average showed a four-helix bundle and a fifth helix in close proximity to the c-ring. Two more helices were present in each position but their position was ambivalent. The data obtained in this work provides the first insight in the helical arrangement in the a-c interface of F1Fo-ATP synthase. Jonna Hakulinen doctoralthesis http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29732 Wed, 10 Apr 2013 08:33:40 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29720 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29720 Mon, 08 Apr 2013 11:00:46 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29706 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29706 Fri, 05 Apr 2013 15:32:47 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29691 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29691 Fri, 05 Apr 2013 13:45:03 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29670 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29670 Thu, 04 Apr 2013 09:36:03 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29669 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29669 Thu, 04 Apr 2013 09:32:54 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29668 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29668 Thu, 04 Apr 2013 09:29:16 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29667 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29667 Thu, 04 Apr 2013 09:25:54 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29666 periodicalpart http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/29666 Thu, 04 Apr 2013 09:21:53 +0200