In: Angewandte Chemie, 2013, vol. 125, no. 17, p. 4780-4783
Einkristall-zu-Einkristall-Umwandlungen sind durch Ionenaustausch- und Transportreaktionen durch supramolekulare Kanäle möglich, die aus Kronenether- Molekülen bestehen und Trihalogenid-Ionen als Gerüst nutzen. In kinetischen Messungen des Ionentransports bei unterschiedlichen Temperaturen wurde die Aktivierungsenergie für solche Systeme bestimmt, und ein schneller Austausch zwischen K+-...
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In: Angewandte Chemie, 2015, vol. 127, no. 10, p. 2954-2958
Einige Mikroorganismen zeigen anaerobe mineralische Respiration, bei der sie Metallionen zu Metallnanopartikeln reduzieren. Hierbei werden Peptide als Medium für den Elektronentransfer (ET) verwendet. Diese Reaktionsklasse wird anhand eines Modellpeptids und Silber als Metall diskutiert. Erstaunlicherweise können Silberionen, die von Peptiden mit Histidin als silberbindender Aminosäure und...
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In: Particle & Particle Systems Characterization, 2020, vol. 37, no. 5, p. 1900419
Metal nanoparticles (NPs), chalcogenides, and carbon quantum dots can be easily synthesized from whole microorganisms (fungi and bacteria) and cell‐free sterile filtered spent medium. The particle size distribution and the biosynthesis time can be somewhat controlled through the biomass/metal solution ratio. The biosynthetic mechanism can be explained through the ion‐reduction theory and...
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In: Particle & Particle Systems Characterization, 2020, vol. 37, no. 5, p. 1900419
Metal nanoparticles (NPs), chalcogenides, and carbon quantum dots can be easily synthesized from whole microorganisms (fungi and bacteria) and cell‐free sterile filtered spent medium. The particle size distribution and the biosynthesis time can be somewhat controlled through the biomass/metal solution ratio. The biosynthetic mechanism can be explained through the ion‐reduction theory and...
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In: Angewandte Chemie International Edition, 2020, vol. 59, no. 30, p. 12331-12336
Anaerobic microorganisms of the Geobacter genus are effective electron sources for the synthesis of nanoparticles, for bioremediation of polluted water, and for the production of electricity in fuel cells. In multistep reactions, electrons are transferred via iron/heme cofactors of c‐type cytochromes from the inner cell membrane to extracellular metal ions, which are bound to outer membrane...
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In: ChemBioChem, 2018, vol. 19, no. 9, p. 922–926
In nature, proteins serve as media for long‐distance electron transfer (ET) to carry out redox reactions in distant compartments. This ET occurs either by a single‐step superexchange or through a multi‐step charge hopping process, which uses side chains of amino acids as stepping stones. In this study we demonstrate that Phe can act as a relay amino acid for long‐distance electron...
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In: Nucleic Acids Research, 1998, vol. 26, no. 17, p. 4063-4067
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In: Pure and Applied Chemistry, 2001, vol. 73, no. 3, p. 449-453
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In: Angewandte Chemie International Edition, 2017, vol. 56, no. 21, p. 5926-5930
The reduction of Ag⁺ ions to Ag⁰ atoms is a highly endergonic reaction step, only the aggregation to Agn clusters leads to an exergonic process. These elementary chemical reactions play a decisive role if Ag nanoparticles (AgNPs) are generated by electron transfer (ET) reactions to Ag⁺ ions. We studied the formation of AgNPs in peptides by photoinduced ET, and in...
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In: The Journal of Physical Chemistry B, 2015, vol. 119, no. 22, p. 6584–6590
Electron transfer over long distances in proteins by a hopping process requires transient relay stations that can harbor charge and spin for a short time span. Certain easily oxidizable or reducible side chains may assume that role, but it has been shown that charge transport in peptides can also take place in the absence of such groups which implies that the peptide backbone provides for hopping...
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