A5032315811- Electrochemical sensors and biosensors
- Electrochemical Analysis and Applications
- Metal-Catalyzed Oxygenation Mechanisms
- Enzyme-mediated dye degradation
- Photosynthetic Processes and Mechanisms
- Mycotoxins in Agriculture and Food
- Antimicrobial Peptides and Activities
- Electrocatalysts for Energy Conversion
- Antimicrobial agents and applications
- Polydiacetylene-based materials and applications
- Oxidative Organic Chemistry Reactions
- Insect and Pesticide Research
- Lipid Membrane Structure and Behavior
- melanin and skin pigmentation
- thermodynamics and calorimetric analyses
- Advanced biosensing and bioanalysis techniques
- Silymarin and Mushroom Poisoning
- Molecular Junctions and Nanostructures
- Catalytic C–H Functionalization Methods
- Mass Spectrometry Techniques and Applications
- Advanced Nanomaterials in Catalysis
- Synthesis and Catalytic Reactions
- Analytical chemistry methods development
- Spectroscopy and Quantum Chemical Studies
- Molecular spectroscopy and chirality
University of Bonn
2022-2024
California Institute of Technology
2018-2022
University of Potsdam
2022
Technische Universität Berlin
2015-2018
Division of Chemistry
2018
Universidade Nova de Lisboa
2013
Abstract We report an iron‐catalyzed decarboxylative C(sp 3 )−O bond‐forming reaction under mild, base‐free conditions with visible light irradiation. The transformation uses readily available and structurally diverse carboxylic acids, iron photocatalyst, 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO) derivatives as oxygenation reagents. process exhibits a broad scope in acids possessing wide range of stereoelectronic properties functional groups. developed was applied to late‐stage series...
Spectroscopic data of dye decolorizing peroxidases (DyPs) from Bacillus subtilis (BsDyP), an A subfamily member, and Pseudomonas putida (PpDyP), a B enzyme, reveal distinct heme coordination patterns the respective active sites. In solution, both enzymes show heterogeneous spin population, with six-coordinated low-spin state being most populated in former five-coordinated quantum mechanically mixed-spin latter. We ascribe poor catalytic activity BsDyP to presence catalytically incompetent...
Cellobiose dehydrogenase catalyzes the oxidation of various carbohydrates and is considered as a possible anode catalyst in biofuel cells. It has been shown that catalytic performance this enzyme immobilized on electrodes can be increased by presence calcium ions. To get insight into Ca(2+) -induced changes we employ surface-enhanced vibrational (SERR SEIRA) spectroscopy together with electrochemistry. Upon addition ions electrochemical measurements show shift turnover signal to more...
In this article, we cross-examine three well-established electrochemical approaches, namely cyclic voltammetry (CV), square-wave (SWV) and impedance spectroscopy (EIS) to dissect the electron transfer (ET) rate of electrostatically immobilized cytochrome c on Ag electrodes. A detailed analysis supported by simulations redox transition provided distinct values for heterogeneous (HET) constant cyt interfaced COOH-terminated C10-long alkanethiol, i.e., kHET= 47.8 (±2,91) s−1 in CV, 64.8 (±1,27)...
Polymeric antimicrobial peptide mimics are a promising alternative for the future management of daunting problems associated with resistance. However, development successful polymers (APs) requires careful control factors such as amphiphilic balance, molecular weight, dispersity, sequence, and architecture. While most earlier developed APs focus on random linear copolymers, advanced architectures proves to be more potent. It is recently multivalent bottlebrush improved antibacterial...
Abstract We report an iron‐catalyzed decarboxylative C(sp 3 )−O bond‐forming reaction under mild, base‐free conditions with visible light irradiation. The transformation uses readily available and structurally diverse carboxylic acids, iron photocatalyst, 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO) derivatives as oxygenation reagents. process exhibits a broad scope in acids possessing wide range of stereoelectronic properties functional groups. developed was applied to late‐stage series...
Immobilization of Cytochrome c oxidase (CcO) on electrodes makes voltage-driven reduction oxygen to water possible. Efficient catalytic turnover in CcO/electrode systems is, however, often observed at large overpotentials that cannot be rationalized by the redox properties enzyme itself. To understand structural basis for this observation, CcO was electrostatically adsorbed amino-functionalized Ag electrodes, and transitions heme a a3 were monitored via surface enhanced resonance Raman...
Abstract The heme‐undecapeptide microperoxidase‐11 (MP‐11) was immobilized on mesoporous antimony‐doped tin oxide (ATO) thin‐film electrodes modified with the positively charged binding promotor polydiallyldimethylammonium chloride. Surface concentrations of MP‐11 1.5 nmol cm −2 were sufficiently high to enable spectroelectrochemical analyses. UV/Vis spectroscopy and resonance Raman revealed that adopts a six‐coordinated low‐spin conformation, as in solution presence polycation. Cathodic...
Enniatins are mycotoxins with well-known antibacterial, antifungal, antihelmintic and antiviral activity, which have recently come to attention as potential mitochondriotoxic anticancer agents. The cytotoxicity of enniatins is traced back their ionophoric properties, in the cyclodepsipeptidic structure results enniatin:cation-complexes various stoichiometries proposed membrane-active species. In this work, we employed a combination surface-enhanced infrared absorption (SEIRA) spectroscopy,...
The structure of cobalt hangman complexes adsorbed on electrodes during HER was analysed <italic>via</italic> surface enhanced Raman spectroscopy.
Hexameric tyrosine-coordinated heme protein HTHP from Silicibacter pomeroyi has been shown to exhibit peroxidase- and catalase-like activity. In the present study, detailed spectroscopic electrochemical investigations were performed analyze redox properties active site structure of HTHP. Potentiometric titration in solution revealed a single transition at -0.54 V (vs Ag/AgCl), indicating six structurally identical tyrosine coordinates hemes. Cyclic voltammetry (CV) immobilized afforded...
We have investigated the roles of tyrosine (Tyr) and tryptophan (Trp) residues in four-electron reduction oxygen catalyzed by Streptomyces coelicolor laccase (SLAC). During normal enzymatic turnover laccases, reducing equivalents are delivered to a type 1 Cu center (CuT1) then transferred over 13 Å trinuclear site (TNC: (CuT3)2CuT2) where O2 occurs. The TNC SLAC is surrounded large cluster Tyr Trp that can provide when flow electrons disrupted. Prior studies Canters co-workers...
While so far it has been possible to calculate vibrational spectra of mixtures at a particular composition, we present here novel cluster approach for fast and robust calculation mole fraction dependent infrared circular dichroism the example acetonitrile/(R)-butan-2-ol mixtures. By assigning weights limited number quantum chemically calculated clusters, can be obtained any desired composition by weighted average single spectra. In this way, peak positions carrying information about...
Enniatins are mycotoxins with well-known antibacterial, antifungal, antihelmintic and antiviral activity, which have recently come to attention as potential mitochondriotoxic anticancer agents. The cytotoxicity of enniatins is traced back ionophoric properties, in the cyclodepsipeptidic structure results enniatin:cation-complexes various stoichiometries proposed membrane-active species. In this work, we employed a combination surface-enhanced infrared absorption (SEIRA) spectroscopy,...
We have investigated the roles of tyrosine (Tyr) and tryptophan (Trp) residues in four-electron reduction oxygen catalyzed by Streptomyces coelicolor laccase (SLAC). During normal enzymatic turnover laccases, reducing equivalents are delivered to a type 1 Cu center (Cu T1 ) then transferred over 13 Å trinuclear site (TNC: T3 2 T2 where O occurs. The TNC SLAC is surrounded large cluster Tyr Trp that can provide when flow electrons disrupted. Canters coworkers shown reacts with reduced variant...
We have investigated the roles of tyrosine (Tyr) and tryptophan (Trp) residues in four-electron reduction oxygen catalyzed by <i>Streptomyces coelicolor</i> laccase (SLAC). During normal enzymatic turnover laccases, reducing equivalents are delivered to a type 1 Cu center (Cu<sub>T1</sub>) then transferred over 13 Å trinuclear site (TNC: (Cu<sub>T3</sub>)<sub>2</sub>Cu<sub>T2</sub>) where O<sub>2</sub> occurs. The TNC...
Polymeric antimicrobial peptide mimics are a promising alternative for the future management of daunting problems associated with resistance. However, development successful polymers (APs) requires careful control factors such as amphiphilic balance, molecular weight, dispersity, sequence, and architecture. While most earlier developed APs focused on random linear copolymers, advanced architectures proved to be more potent in mimicry peptides. We recently multivalent bottlebrush improved...