Universität Stuttgart
Permanent URI for this communityhttps://elib.uni-stuttgart.de/handle/11682/1
Browse
135 results
Search Results
Item Open Access Genetisch modifizierte Biotemplate zur Erzeugung von Zr-basierten Nanomaterialien(2019) Eisele, Rahel; Bill, Joachim (Prof. Dr.)In Biomineralisationsprozessen aus der belebten Natur scheiden sich anorganische Materialien auf organischen Templaten (Biomakromoleküle) ab. Funktionelle Gruppen der Makromoleküle steuern dabei die Abscheidung aus einer wässrigen Lösung sowie die Strukturierung des anorganischen Materials. Dabei sind spezifische Wechselwirkungen zwischen dem organischen Templat und dem anorganischen Material von Bedeutung. Die Materialbildung findet unter Umgebungsbedingungen in wässrigen Systemen statt. Für technisch interessante Materialien wie Zirkoniumdioxid (ZrO2) stellt die energieeffiziente Herstellung präziser Nanostrukturen eine technische Herausforderung dar. Daher wurden im Rahmen dieser Arbeit die Prinzipien der Biomineralisation auf die Herstellung von Zirkonium-basiertem Material (ZrbM) übertragen. Hierzu gehörte die Materialbildung durch Mineralisation aus einer ZrOCl2-Lösung sowie eine gezielte Mineralisation auf bioorganischen M13-Bakteriophagentemplaten. Um die „biologische Spezifität“ in Biomineralisationsprozessen auf die Bildung von ZrbM zu übertragen, wurden Peptide mittels Phagen-Display identifiziert, die spezifisch an ZrO2 binden. Mittels genetischer Modifikation wurden diese ZrO2 Bindepeptide auf der Phagenoberfläche präsentiert. Hierdurch wurde eine hohe Bindepeptiddichte und damit viele Interaktionspunkte zum anorganischen Material erzielt. Bevor der Einfluss dieser Bindepeptide auf die Mineralisation von ZrbM untersucht werden konnte, wurde zunächst der Partikelbildungs- und Partikelwachstumsprozess von ZrbM in einer ZrOCl2-Lösung und einem Ethanol-Wasser Lösungsmittelgemisch bei verschiedenen System- und Prozessparametern beschrieben. Auf Grundlage dieser Ergebnisse wurde eine Mineralisationslösung etabliert mit der der Einfluss der Bindepeptide - präsentiert auf der Phagenoberfläche - auf die Mineralisation von ZrbM untersucht werden konnte. Die Bindepeptide zeigten einen deutlichen Einfluss auf die Mineralisation von ZrbM. Im Vergleich zu Bakteriophagen ohne Bindepeptid wurde mit den genetisch modifizierten Bakteriophagen eine deutlich höhere Abscheiderate erzielt. Dieser Einfluss der Bindepeptide wurde auf Hydroxygruppen in Serineinheiten zurückgeführt. Diese führen zum einen zu einer starken Anziehung von molekularen Zr-Spezies an das Biotemplat. Zum anderen induzieren die Hydroxygruppen die heterogene Keimbildung von ZrbM durch Kondensationsreaktionen zwischen dem Biotemplat und molekularen Zr-Spezies. Somit ist es nun möglich genetisch kontrolliert Zr-basierte Nanomaterialien zu mineralisieren. Im Rahmen dieser Arbeit gelang es nicht nur einzelne Phagen zu mineralisieren, sondern auch dünne homogene Schichten aus ZrbM. Diese ZrbM-Schichten wurden im letzten Teil dieser Arbeit vergleichend zu Phagenschichten und SiO2-Schichten auf die Adhäsion von Staphylococcus aureus (S. aureus) getestet. S. aureus ist ein pathogenes Bakterium, welches zur Bildung von Biofilmen, zum Beispiel auf Implantaten, und dadurch zu einem Implantatverlust bis hin zu lebensbedrohlichen Komplikationen führen kann. Die Biofilmbildung kann effektiv unterbunden werden, indem die Bakterienadhäsion auf Oberflächen verhindert wird. Daher wurde im Rahmen dieser Arbeit untersucht, ob bestimmte chemische Oberflächen, das heißt bestimmte Materialien oder auch bestimmte funktionelle Gruppen, die Bakterienadhäsion unterdrücken können. Die Untersuchung der Bakterienadhäsion auf den verschiedenen Oberflächen ergab, dass auf der Phagenschicht im Vergleich zur SiO2-Schicht und einer Schicht aus ZrbM eine sehr geringe Bakterienadhäsion vorlag. Untersuchungen verschiedener Einflussfaktoren auf die Bakterienadhäsion zeigten, dass die Bakterienadhäsion an der SiO2-Schicht und der ZrbM-Schicht durch die Oberflächenrauigkeit, die Hydrophobizität und die Oberflächenladung beeinflusst werden kann. Bei der Phagenschicht korrelierten weder die Oberflächenladung, noch die Oberflächenrauigkeit und die Hydrophobizität im Vergleich zu den anorganischen Materialoberflächen mit der Bakterienadhäsion. Dies ließ darauf schließen, dass die geringe Bakterienadhäsion auf der Phagenschicht auf die biochemische Zusammensetzung der Hüllproteine, vor allem auf die Abwesenheit spezifischer Bindedomänen (Ligand-Rezeptor-Wechselwirkungen), zurückzuführen ist.Item Open Access Development of artificial single and double reading domains to analyze chromatin modification patterns(2018) Mauser, Rebekka; Jeltsch, Albert (Prof. Dr.)The unstructured N-terminal tails of histone proteins carry many different post-translational modifications (PTMs), like methylation, acetylation or phosphorylation. These PTMs can alter the chromatin structure, influence the interaction of adjacent nucleosomes and serve as specific binding sites for histone interacting domains. Currently, the investigation of histone tail PTMs is mainly based on antibodies, however concerns about the specificity of these antibodies and reproducibility of data arouse. Therefore, it was one aim of this thesis to develop alternative approaches to histone tail PTM antibodies. Previous studies already showed that histone modification interacting domains (HiMIDs) can replace histone tail antibodies in a highly effective manner. As part of this work, the TAF3 PHD domain was established as new H3K4me3 specific HiMID. In peptide array binding and Far-western blot assays, the domain showed a specific interaction with H3K4me3 modifications. Also in ChIP like experiments (CIDOP: Chromatin Interacting Domain Precipitation) coupled to qPCR and next generation sequencing, the domain showed a similar performance as validated H3K4me3 antibodies. With the proposal of the histone code hypothesis the question was raised if combinations of histone modifications carry specific biological functions. However, so far, the experimental analysis of the co-occurrence of histone modification on the same nucleosome in a genome-wide manner is a challenging task. For this reason, the main aim of this work was to develop double reading domains in which two histone reading domains are fused together with a flexible linker to achieve simultaneously readout of dual histone tail modifications in a single CIDOP experiment. To validate the concept, the Dnmt3a PWWP domain and the MPP8 Chromo domain were fused together and their specific recognitions of H3K36me2/3 and H3K9me3 histone tail modifications were analyzed. Biochemical investigations like peptide arrays, Far-western blot and western blot experiments showed that both domains specifically interact with their targets and preferentially interact with double modified chromatin. Additionally, the preferred interaction with double modified chromatin could be further verified with binding pocket mutants and methyl-lysine analogues. The newly generated double domain was used in chromatin precipitation experiments to identify genome regions where both modifications are present. The genome-wide distribution of the H3K36me2/3-H3K9me3 showed that this combination of histone marks represents a novel bivalent chromatin state, which is associated with weakly transcribed genes and is enriched for binding sites of ZNF274 and SetDB1. Also in this work, mixed peptide arrays were introduced as new screening method for the efficient analysis of double reading domains. The naturally occurring double reading domain of the BPTF protein was used to demonstrate the capability of this new screening tool. BPTF contains a PHD domain, which binds to H3K4me3 and a Bromo domain, which interacts with acetyl groups of the H4 tail. Synergistic binding to both peptides was shown using the newly developed mixed peptide arrays. Additionally, in the course of this work mixed peptide arrays were used to optimize several of the designed double reading domains. Furthermore, some other double reading domains were generated in this work, like PWWP-ATRX, MPP8 Chromo domain-L-double Tudor and CBX7 Chromo domain-L-MPP8 Chromo domain and analyzed for specific dual readout. Also double reading domains with dual specificity for DNA methylation and histone marks were generated. The firstly used methyl-DNA binding domain of the MBD2 protein showed a strong binding, dominating the effect of the HiMIDs. Therefore, the weaker but still specific methyl-DNA binding domain of the MBD1 protein was used. First experiments with this new fusion constructs showed a simultaneously interaction with chromatin which is associated with DNA methylation and histone PTMs. In summary, the studies with double reading domains showed that with this novel method precipitation of double modified chromatin is possible and that the genome-wide investigation of newly studied bivalent chromatin states is feasible. Therefore, this novel approach makes it possible to analyze many different combinations of histone modifications, investigate their influence on chromatin and gain a deeper understanding of the biological role behind histone tail modification patterns.Item Open Access Physical interactions strengthen chemical gelatin methacryloyl gels(2019) Rebers, Lisa; Granse, Tobias; Tovar, Günter E. M.; Southan, Alexander; Borchers, KirstenChemically cross-linkable gelatin methacryloyl (GM) derivatives are getting increasing attention regarding biomedical applications. Thus, thorough investigations are needed to achieve full understanding and control of the physico-chemical behavior of these promising biomaterials. We previously introduced gelatin methacryloyl acetyl (GMA) derivatives, which can be used to control physical network formation (solution viscosity, sol-gel transition) independently from chemical cross-linking by variation of the methacryloyl-to-acetyl ratio. It is known that temperature dependent physical network formation significantly influences the mechanical properties of chemically cross-linked GM hydrogels. We investigated the temperature sensitivity of GM derivatives with different degrees of modification (GM2, GM10), or similar degrees of modification but different methacryloyl contents (GM10, GM2A8). Rheological analysis showed that the low modified GM2 forms strong physical gels upon cooling while GM10 and GM2A8 form soft or no gels. Yet, compression testing revealed that all photo cross-linked GM(A) hydrogels were stronger if cooling was applied during hydrogel preparation. We suggest that the hydrophobic methacryloyl and acetyl residues disturb triple helix formation with increasing degree of modification, but additionally form hydrophobic structures, which facilitate chemical cross-linking.Item Open Access Enzymatic asymmetric dihydroxylation of alkenes(2016) Gally, Christine; Hauer, Bernhard (Prof. Dr.)The introduction of chirality into C=C double bonds is of special interest in organic synthesis. In particular, the catalytic asymmetric dihydroxylation (AD) of alkenes has attracted considerable attention due to the facile transformation of the chiral diol products into valuable derivatives. By chemical means, the metal-catalyzed AD of olefins provides both stereo- and regiospecific cis-diol moieties. Next to their toxicity, however, these metal catalysts can also lead to byproduct formation as a result of oxidative fission. In nature, Rieske non-heme iron oxygenases (ROs) represent promising biocatalysts for this reaction since they are the only enzymes known to catalyze the stereoselective formation of vicinal cis-diols in one step. ROs are key enzymes in the degradation of aromatic hydrocarbons and can target a wide variety of different arenes. Despite their broad substrate scope, limited data is available for the conversion of unnatural substrates by this class of enzymes. To explore their potential for alkene oxidation, three ROs were tested for the oxyfunctionalization of a set of structurally diverse olefins including linear and cyclic arene-substituted alkenes, cycloalkenes as well as several terpenes. Naphthalene- (NDO), benzene- (BDO) and cumene dioxygenases (CDO) from different Pseudomonas strains where selected as they are amongst the RO enzymes that have already been reported to catalyze the oxidation of a small number of olefins. The majority of compounds from the selected substrate panel could be converted by NDO, BDO or CDO and products were either isolated and identified by NMR analysis or using the authentic standards. Dependent on the substrate, allylic monohydroxylation was found in addition to the corresponding diol products, a reaction which is chemically still most reliably achieved by the use of SeO2 in stoichiometric amounts. However, having been evolved for the dihydroxylation of aromatic compounds, wild type ROs displayed low conversions (< 50%) and modest stereoselectivities (≤ 80% ee/de) for several of the tested olefins. To overcome these limitations, changes in the active site topology of RO catalysts were introduced. A single targeted point mutation that was identified based on sequence and structural comparisons with other members of the RO family proved to be sufficient to generate BDO and CDO variants displaying remarkable changes in regio- and stereoselectivity for various substrates. In particular biotransformations with CDO M232A gave excellent stereoselectivities (≥ 95% ee/de) and good activities (> 90%) also for linear alkenes, which have been reported to be challenging substrates for RO-catalyzed oxyfunctionalizations. Site-saturation mutagenesis at position 232 in CDO revealed a correlation between the steric demand of the amino acid side chain and its influence on regio- and/ or stereoselectivities for styrene and indene. While the wild type enzyme almost exclusively catalyzed the dihydroxylation of the aromatic ring, the regioselectivity was shifted with decreasing side chain size to the terminal vinyl group of styrene, yielding up to 96% of the alkene-1,2-diol. For cis-1,2-indandiol formation, enantiocomplementary enzymes could be generated, a fact further highlighting the importance of position 232 for the engineering of ROs. Moreover, site-saturation mutagenesis of additional residues in the substrate binding pocket of CDO (F278, I288, I336 and F378) identified further positions having an influence on selectivity and product formation for alkene oxidation. To proof the applicability of ROs for organic synthesis, semi-preparative scale biotransformations (70 mg) of selected substrates were performed with CDO M232A. Without further optimization of the reaction set-up, products were successfully isolated in > 30% yield. In addition, up-scaling of (R)-limonene hydroxylation to 4 L in a bioreactor with growing cells gave final isolated product titers of 0.4 g L-1 even though substrate volatility and product toxicity diminished the yield. In conclusion, these examples demonstrated that a single point mutation was sufficient to transform CDO wild type into an efficient catalyst, furthermore constituting the first example of the rational engineering of CDO and BDO enzymes for the oxyfunctionalization of a broad range of alkenes.Item Open Access Using umbrella integration to find minimum free energy paths(2015) Bohner, Matthias Ulrich; Kästner, Johannes (Prof. Dr.)The analysis of the detailed mechanism of chemical reactions is a key task of computational chemistry. The detailed knowledge may help to improve known processes or even contribute to the development of new ones. In this way ecological and economic demands can be reduced. Furthermore, the course of a reaction path also plays an important role in the action of drugs. Understanding the binding of the active ingredient to receptors, such as proteins, can make it possible to optimize drugs by reducing side effects, or even to find new effects. Unfortunately, chemical reactions are usually too fast to observe intermediate states by experimental methods. This is where theoretical chemistry joins the game. In theoretical chemistry we combine the coordinates of all atoms with the configuration space. The potential energy forms a hypersurface in this space. Minima represent stable or metastable states. Saddle points represent transition states which are the most unfavourable configurations occurring on the most favourable path between two minima. If the path of a reaction is known, all intermediate states can be observed by theoretical methods. However, these calculations are usually computationally costly. This is the reason why, in contrast to experimental methods, it is in general impossible to sample the whole configuration space. This would in most cases exceed the available computational resources. It is therefore necessary to use techniques enabling a reaction path to be found without sampling the whole configuration space. In the case of a thermodynamic ensemble, e.g. the contents of a test tube, statistical information has to be included. The corresponding potential is the so-called free energy landscape, for which some degrees of freedom of the configuration space are thermostatistically integrated out. Consequently this function includes statistical and energetic properties. The free energy can in general only be calculated by statistical simulations (Monte--Carlo or molecular dynamics). Unfortunately, the transition states in which we have a special interest are rarely sampled. Special methods have to be applied to get sufficient sampling as well in areas of these rare events. In this work a non-physical quadratic potential is used to bias the equation of motion of the particles while doing molecular dynamics simulations. In this way unfavourable areas in the configuration space can also be sampled sufficiently. This technique is called umbrella sampling. The bias is applied to one or more coordinates which describe the reaction and therefore are called reaction coordinates. An umbrella sampling run will result in a distribution of the reaction coordinates. The expectation value of this distribution will be located close to the minimum of the bias function without in general corresponding to it. The difference between the minimum of the bias function and the expectation value can be used to calculate the gradient of the underlying free energy surface. Similarly, the covariance of the distribution of the reaction coordinate can be used to calculate the Hessian of the free energy surface. This method of interpreting the data gained by umbrella sampling is called umbrella integration. At first these values are used for an iterative search of the saddle points, which represent the transition states. From these configurations, free energy paths can be constructed by following the gradient down to the minima. This algorithm was successfully tested for the alanine dipeptide system. This simple method has the disadvantages that it works serially and that one needs good initial guesses for the saddle points in order to find them. Therefore, in a second part of the work, the established method of nudged elastic band optimization (NEB) is extended for use in the free energy surface. NEB optimization searches for a reaction path. This path is discretized into a number configurations, so-called images. For the sake of equal distribution of the images along the path a non-physical spring force between the images is used. The force, which is actually minimized during the NEB optimisation, consists of the projection of the real force of the underlying potential perpendicular to the path, and the projection of the spring force parallel to the path. An optimizer is developed which archives quadratic convergence of NEB optimizations in the noise-free potential energy surface of some test systems. This optimiser uses gradients and Hessians at each step. For the free energy surface both values can be calculated by umbrella integration as mentioned above. NEB optimizations within the free energy are performed in this work in the following way: at first a guess path is assumed, e.g. a straight line between two points in the configuration space, usually minima. This path is discretized into a number of images. Molecular dynamics umbrella sampling simulations are performed on each image. The gradient and Hessian from the umbrella integration are fed into the newly developed NEB optimizer. This way one does not need good starting guesses for the saddle points but an interpolation between the much more easily accessible minima is sufficient. Furthermore, the need for independent molecular dynamics runs at each image makes the method intrinsically parallel. The whole method is applied to the well-studied alanine dipeptide system and compared with the results from the serial method. Subsequently the algorithm is applied to a much more costly system of binding a ligand to its receptor in water.Item Open Access Determination of biomechanical and architectural muscle properties : from single muscle fibre to whole muscle mechanics(2018) Tomalka, André; Siebert, Tobias (Prof. Dr.)The work presented in this thesis aims to provide a more detailed insight in the complex physiology of certain muscle tissue types. This thesis builds upon the results of in vitro contractile and ex vivo architectural experiments with muscle tissue preparations from rats (Rattus norvegicus), rabbits (Oryctolagus cuniculus) and pigs (Sus scrofa domesticus) - investigated by experimental and modelling approaches. During the course of this work the chapters are intended to determine, describe and interprete the distinct properties of muscle tissue samples of striated skeletal and smooth musculature. These species-specific properties have not been observed before, but are needed for modelling approaches and a better understanding of contractile mechanics and muscle growth. Despite the numerous studies on skeletal and smooth muscle tissue, there are still fundamental questions about the physiology and force generation of the muscle. Hence, the determination of specific biomechanical and architectural muscle properties allows a quantitative understanding of the mechanisms involved in force development. Moreover, this is a crucial step towards reliable, realistic muscle models and thus also to increased predictive quality of muscle-driven multi-body models.Item Open Access Mid-infrared resonant nanostructures for in-vitro monitoring of polypeptides(2019) Semenyshyn, Rostyslav; Giessen, Harald (Prof. Dr.)Infrared vibrational spectroscopy is a technique based on the molecular vibrations, that is, the oscillation of individual atoms with respect to each other. Each of these vibrations has a characteristic resonance frequency which leads to the distinct vibrational fingerprint of a molecule and thus enables a label-free, non-destructive, and chemically specific detection of molecular species. The infrared absorption cross-sections, which characterize the optical interaction strength, are relatively small. This is of minor importance for conventional spectroscopy, where large ensembles of molecules can be measured and thus contribute to the overall signal. However, the small infrared absorption hampers detection of molecules at low concentrations, which is of large importance for medical diagnostics, for instance, where the determination of the secondary structures of proteins is crucial due to their role in many incurable diseases. A key to overcome this limitation is to utilize plasmonic nanostructures, which confine the electromagnetic radiation on the nanometer scale and allow higher overall absorption. In this dissertation, it is demonstrated that even a monolayer of proteins can be detected using mid-infrared resonant gold nanostructures. We use polypeptides as a model system and were able to investigate the secondary structure of molecular monolayers in-vitro. Applying different external stimuli, we are able to induce structural changes of polypeptides in aqueous environments. In addition to a mid-infrared resonant nanoantenna, nanoslits (or inverse antennas) can also enhance the optical response of polypeptides, which allowed us to detect the secondary structure of minicollagen monolayers. Both nanostructure designs provided the possibility even to monitor reversible conformational transitions of molecular monolayers. Scaling this approach down to a single nanostructure allows to detect only a few thousands of polypeptides in liquid environments. The demonstrated concept could lead to integrated chip-level technology for biological and even medical applications, where biosamples with minute concentrations are investigated. With further advances, it could be possible to scale the process to a few or single proteins and observe the structural changes of individual entities.Item Open Access Understanding the mechanisms of robustness in intracellular protein signalling cascades and gene expression(2018) Paul, Debdas; Radde, Nicole (Prof. Dr. rer. nat.)We seek to understand the structural as well as the mechanistic basis of robustness in intracellular protein signalling cascades and in transcriptional regulation of gene expression. For protein signalling cascades, we employ a comparison based study involving a single, a double and a cascade of two double phosphorylation-dephosphorylation (PD) cycles. Using deterministic modelling approaches based on ordinary differential equations (ODE), we observe that the cascade of two double PD cycles exhibits robust output behaviour compared to that of a single and a double PD cycle upon constant as well as time- varying input perturbations. Furthermore, a system theoretic analysis reveals that the protein phosphorylation cascades act as an efficient low-pass filter that attenuates the noise mimicked as high-frequency input signals. Afterwards, we extend the study for a stochastic environment. Simulation results based on the stochastic simulation algorithm (SSA) reveal a novel phenomenon called dynamic sequestration that plays an ambivalent role as an intrinsic noise filter. Overall, the analysis indicates that complexity can be one of the basic principles of robust biological designs such as intracellular protein signalling cascades. A major function of intracellular signalling cascades is to transmit the extracellular signal to the nucleus to initiate the process of gene expression. Gene expression is an intrinsically stochastic process that results into cell-to-cell variability in protein and messenger RNA (mRNA) levels, often termed as the expression noise. In spite of such noise, how cells achieve robustness is therefore a fundamental biological problem. We conclude the thesis by introducing a rule-based modelling approach based on the Kappa (κ) platform with the goal to understand the underlying mechanisms that ensure robust cellular functioning during gene expression. In particular, we introduce a gene expression model that keeps the process of transcription and excludes the process of translation. Therefore, we quantify the expression noise using mRNA which is the end product of transcription. Besides, the motivation behind adopting a rule-based modelling approach is that unlike the ODE-based approach, the former subsumes the combinatorial complexity arises due to various binding configurations of transcription factors (TF) for regulation of gene expression and offers a compact graphical representation of the same. Afterwards, the representation is transformed into an equivalent set of executable κ rules that are simulated using the SSA to obtain distributions of mRNA copy numbers corresponding to different regulatory mechanisms.Item Open Access Peptide controlled shaping of biomineralized tin(II) oxide into flower-like particles(2019) Kilper, Stefan; Jahnke, Timotheus; Wiegers, Katharina; Grohe, Vera; Burghard, Zaklina; Bill, Joachim; Rothenstein, DirkThe size and morphology of metal oxide particles have a large impact on the physicochemical properties of these materials, e.g., the aspect ratio of particles affects their catalytic activity. Bioinspired synthesis routes give the opportunity to control precisely the structure and aspect ratio of the metal oxide particles by bioorganic molecules, such as peptides. This study focusses on the identification of tin(II) oxide (tin monoxide, SnO) binding peptides, and their effect on the synthesis of crystalline SnO microstructures. The phage display technique was used to identify the 7-mer peptide SnBP01 (LPPWKLK), which shows a high binding affinity towards crystalline SnO. It was found that the derivatives of the SnBP01 peptide, varying in peptide length and thus in their interaction, significantly affect the aspect ratio and the size dimension of mineralized SnO particles, resulting in flower-like morphology. Furthermore, the important role of the N-terminal leucine residue in the peptide for the strong organic-inorganic interaction was revealed by FTIR investigations. This bioinspired approach shows a facile procedure for the detailed investigation of peptide-to-metal oxide interactions, as well as an easy method for the controlled synthesis of tin(II) oxide particles with different morphologies.Item Open Access Präzise Fahrzeugpositionierung durch Entzerrung der gepulsten magnetischen Flussdichteverteilung einer Ladespule(2017) Martinovic, Dean; Reuss, Hans-Christian (Prof. Dr.-Ing.)Elektrofahrzeuge werden in Zukunft nicht mehr per Kabel, sondern mittels induktiver Ladesysteme mit Strom versorgt. Um eine hohe Ladeleistung sicher übertragen zu können, müssen die Spulen hinreichend genau übereinander positioniert werden, was für den Fahrer eine kaum lösbare Aufgabe darstellt. Das allgemeine Ziel der vorliegenden Arbeit ist es daher, eine neue Methode zu untersuchen, die ein gepulstes Magnetfeld der Ladespule zu dessen Ortung nutzt. Hierbei wird das magnetische Pulssignal durch den ferromagnetischen Unterboden des Elektrofahrzeugs verzerrt. Dieser verändert die Pulsamplitude entsprechend einer unbekannten Abbildung, ohne deren Kenntnis eine präzise und eindeutige Positionierung nicht möglich ist. Die Herausforderung der vorliegenden Arbeit ist daher die Bestimmung dieser Abbildung samt ihrer Eigenschaften und Abhängigkeiten. Theoretische Untersuchungen zeigen, dass die Abbildung allgemein vom nicht-deterministischen magnetischen Zustand des Unterbodenmaterials abhängt und dessen messtechnische Erfassung kaum möglich ist. Im weiteren Verlauf der Untersuchungen wird jedoch hergeleitet, dass die Ladespule, das Elektrofahrzeug und die umgebende Atmosphäre zusammen einen magnetischen Kreis bilden, der aufgrund der sehr hohen Reluktanz der Atmosphäre linear ist. Änderungen des magnetischen Zustands haben folglich keinen Einfluss auf die Abbildung. Diese ist somit reproduzierbar und kann messtechnisch einfach erfasst werden. Die These wird für unterschiedliche magnetische Zustände experimentell nachgewiesen. Basierend auf den Forschungsergebnissen wird ein vollständiger Prototyp entwickelt und in ein Versuchsfahrzeug integriert. Das Gesamtsystem wird anschließend erfolgreich getestet. Die gefundenen Ergebnisse zeigen, dass mittels gepulster magnetischer Felder eine universelle, kostengünstige, sichere und präzise Positionierung von Elektrofahrzeugen möglich ist. Dies unterstreicht das Potential des neuen, komfortablen Positionierungsverfahrens eine Schlüsseltechnologie für die Elektromobilität zu werden.