Universität Stuttgart

Permanent URI for this communityhttps://elib.uni-stuttgart.de/handle/11682/1

Browse

Filters

2020 - 202548

Settings

Publication Type: search.filters.UBSTyp.Verschiedenartige TexteStart date: 2020

Search Results

Now showing 1 - 10 of 48
  • Thumbnail Image
    ItemOpen Access
    The triple variant K170D/N174L/D239A compensates the destabilizing effect of variant K170D/N174L in β-hydroxyacid dehydrogenase (βHAD) from Arabidopsis thaliana
    (2020) Schelle, Luca S.; Stockinger, Peter; Pleiss, Jürgen; Nestl, Bettina M.
    Chiral amines are essential building blocks in biologically active compounds, fine chemicals, agrochemicals and pharmaceuticals. In the last ten years, various enzymes were identified as new biocatalysts for chiral amine synthesis. Promising enzymes for the synthesis of primary, secondary, and tertiary amines are NADPH-dependent imine reductases (IREDs). Bioinformatics analysis revealed that IREDs are closely related to β-hydroxyacid dehydrogenases (βHADs). In recent work, we engineered the βHAD from Arabidopsis thaliana (βHAD_At) into imine-reducing enzymes by a single amino acid exchange. The exchange of the proton-donor described lysine (K170) in βHAD_At by aspartic acid, the most common amino acid at this position in R-selective IREDs, led to a 12-fold increase in activity for the model substrate 2-methylpyrroline. At the same time, the activity for the natural substrate glyoxylic acid is reduced 885-fold, resulting in a total of 8200-fold change in catalytic activity through the exchange of an amino acid. At the same time, highly decreased soluble expression has been observed by exchanging asparagine at position 174 (N174) with leucine. We thus hypothesized, that the aspartic acid residue (D239) in near proximity to N174 will stabilize the underlying α-helix. Consequently, replacement of D239 with alanine should result in soluble expression of variants containing the N174 mutations. We generated variants K170D/D239A, as well as, and tested them on imine reduction of test substrates 2-methylpyrroline, 3,4-dihydroisoquinoline and 6-phenyl-2,3,4,5-tetrahydropyridine. Due to loss of essential cofactor and precipitation of purified proteins during purification procedure, activities of variants were determined using cell lysates. Notably, variants N174L/D239A and K170D/N174L/D239A demonstrated soluble expression and imine-reducing activities of up to 98 mU per mg of variant.
  • Thumbnail Image
    ItemOpen Access
    SyKonaS - Projektbericht. Nr. 1, Konflikte in der Energiewende: Definitionen und Typologien
    (Stuttgart : Verbundvorhaben SyKonaS, Zentrum für interdisziplinäre Risiko- und Innovationsforschung der Universität Stuttgart (ZIRIUS), 2022) Minn, Fabienne; Wassermann, Sandra; León, Christian D.; Püttner, Andreas (Mitwirkender); Liebhart, Laura (Mitwirkende); Wolf, Patrick (Mitwirkender)
    Das Forschungsprojekt "SyKonaS: Systemische Konfliktanalyse mittels Szenariotechnik" hat zum Ziel, gesellschaftliche Konflikte und deren Wechselwirkungen in der Energiewende zu verstehen, zu antizipieren und Lösungsvorschläge zu entwickeln. Im Rahmen dieser Zielsetzung wurden im Arbeitspaket 1 des Projektes die Konflikte der Energiewende empirisch aufgearbeitet und eine systematische Typologie von Energiewendekonflikten entwickelt (Task 1). Im vorliegenden Bericht werden das Vorgehen und die erzielten Ergebnisse beschrieben.
  • Thumbnail Image
    ItemOpen Access
    Schaustücke : Einblicke in wissenschaftliche Sammlungen der Universität Stuttgart
    (Stuttgart : Universität Stuttgart, 2022) Wiatrowski, Frank (Gestaltung, Fotograf); Engstler, Katja Stefanie (Gestaltung); Ceranski, Beate (Vorwort); Rambach, Christiane (Vorwort)
    Die wissenschaftlichen Sammlungen der Universität zeugen von einer langen Lehr- und Forschungstradition. In Fakultäten und Instituten, in der Universitätsbibliothek und im Universitätsarchiv sind vielfältige Sammlungen beheimatet, zum Teil mit ungewöhnlichen oder gar einzigartigen Objekten. Die Broschüre gibt erste Einblicke in diese vielfach versteckte Welt der universitären Sammlungen in Stuttgart.
  • Thumbnail Image
    ItemOpen Access
    Context scenarios of the German Energy Transition : a data collection for the analysis of the socio-political framework of a socio-technical transformation
    (2020) Weimer-Jehle, Wolfgang; Prehofer, Sigrid; Hauser, Wolfgang; Bräutigam, Klaus-Rainer (Translator); Buchgeister, Jens (Translator); Kopfmüller, Jürgen (Translator)
    An expert survey about the socio-technical context of the German Energy Transformation is described and selected results are reported. Major socio-technical drivers of the energy system and its evolution were identified, alternative futures for each driver were derived based on literature review and expert questioning. Using the framework of Cross-Impact Balance Analysis, the interrelations between the possible futures of the drivers were estimated by a series of expert interviews.
  • Thumbnail Image
    ItemOpen Access
    A method for describing, analyzing, and exploring visual art collections
    (2024) Pflüger, Hermann
    Visual art collections are more than just sets of images. Behind a collection or an exhibition are the curator’s concept and the specific characteristics of the collection. A controlled vocabulary that takes into account the concept and the specific characteristics of a collection requires individual terms/concepts, and specific relationships between the concepts of the vocabulary. Furthermore, the granularity of a controlled vocabulary should be adapted to a particular concept of the collection, i.e., for some areas, the number of terms/concepts should be very high and specific; for other areas, concepts should be summarized to keep the complexity of the collection low and thus facilitate the handling and presentation of the collection. A LadeCA vocabulary is an extended controlled vocabulary that is particularly suitable for collections of works of art. LadeCA enables a user to describe, analyze, and explore art collections. LadeCA is also suitable for comparing the contents of different collections or different parts of a collection. The general concepts of a controlled vocabulary/thesaurus, their terms, and defined semantic relations between them can be automatically adopted in a LadeCA vocabulary so that the vocabulary only needs to be adapted for the current collection. The process of creating a LadeCA vocabulary for art collections is supported by three interactive interfaces that ensure that the intention behind a collection is taken into account, and that the creation effort is kept low. This article explains the process of creating LadeCA vocabularies for art collections and describes the initial experiences and results.
  • Thumbnail Image
    ItemOpen Access
    SyKonaS - Projektbericht. Nr. 5, Systemische Analyse der Wechselwirkungen zwischen Konfliktlinien und Rahmenbedingungen der Energiewende: Weiterentwicklung soziotechnischer Energieszenarien
    (Stuttgart : Verbundvorhaben SyKonaS, Zentrum für interdisziplinäre Risiko- und Innovationsforschung der Universität Stuttgart (ZIRIUS), 2024) Hauser, Wolfgang; Wassermann, Sandra; Oviedo, Patricia; León, Christian D.; Weimer-Jehle, Wolfgang; Jaschek, Carolin (Mitwirkende); Prehofer, Sigrid (Mitwirkende)
    Im Teilvorhaben SyKonaS/iKonS („Systemische Konfliktanalyse mittels Szenariotechnik“) wurden die technoökonomischen Szenarien um soziale Größen ergänzt und zu soziotechnischen Szenarien weiterentwickelt, um ihre jeweilige Konflikthaftigkeit abzuschätzen. Hierfür wurden zwölf durch die technoökonomischen Energieszenarien vorgegebene Größen (wie z.B. die installierte Leistung von Wind onshore im Jahr 2050) und ihre Wirkungen auf zwölf sozio-politische Größen abgeschätzt. Ebenso wurden die Interdependenzen der soziopolitischen Größen erhoben. Es wurde dann die Frage gestellt, welche Konflikte von den verschiedenen Energieszenarien und ihren gesellschaftlichen Wirkungen ausgelöst werden können.
  • Thumbnail Image
    ItemOpen Access
    Guidelines for a finite element based design of timber structures
    (Stuttgart : University of Stuttgart, Institute of Structural Design, 2022) Töpler, Janusch; Kuhlmann, Ulrike
  • Thumbnail Image
    ItemOpen Access
    Formal security analysis of the OpenID FAPI 2.0 Security Profile with FAPI 2.0 Message Signing, FAPI-CIBA, Dynamic Client Registration and Management : technical report
    (2023) Hosseyni, Pedram; Küsters, Ralf; Würtele, Tim
    Building on our recent formal security analysis of the FAPI 2.0 Security Profile, we here extend the analysis effort to FAPI 2.0 Message Signing, combined with Dynamic Client Registration, Dynamic Client Management, and FAPI-CIBA. Overall, we model an ecosystem which uses all these profiles and extensions in parallel. Like the previous work on the FAPI 2.0 Security Profile, this analysis is based on the Web Infrastructure Model, a Dolev-Yao style model of the web infrastructure - in fact, it is the most comprehensive and detailed model of the web infrastructure to date. We identify several attacks, propose fixes and prove the fixed protocols secure with respect to authorization, authentication, session integrity for both authorization and authentication, and non-repudiation for the messages covered by FAPI 2.0 Message Signing. The attacks and proposed fixes have been reported to the responsible FAPI Working Group at the OpenID Foundation, and fixes have since been incorporated into the specifications.
  • Thumbnail Image
    ItemOpen Access
    Umgang mit Forschungssoftware an der Universität Stuttgart
    (2020) Flemisch, Bernd; Hermann, Sibylle; Holm, Christian; Mehl, Miriam; Reina, Guido; Uekermann, Benjamin; Boehringer, David; Ertl, Thomas; Grad, Jean-Noël; Iglezakis, Dorothea; Jaust, Alexander; Koch, Timo; Seeland, Anett; Weeber, Rudolf; Weik, Florian; Weishaupt, Kilian
    Wir empfehlen die Einrichtung einer Organisationseinheit Forschungssoftware-Entwicklung an der Universität Stuttgart und eines daran angegliederten Stellenpools von Research Software Engineers (RSEs). Dazu schlagen wir Maßnahmen zur Schaffung und Finanzierung entsprechender neuer RSE-Stellen, zur Integration bestehender Stellen sowie zur Gewinnung und Förderung geeigneter Personen vor. RSEs sind Personen, die sich um Konzeption, Organisation, Implementierung, Testen, Dokumentation und Wartung von Forschungssoftware kümmern. Die institutionelle Förderung von Forschungssoftware-Entwicklung ist notwendig, da die Bedeutung von Software für die Forschung und Anforderungen an die entsprechende Software, u.a. durch die DFG, stetig zunimmt.
  • Thumbnail Image
    ItemOpen Access