Article
Chemistry, Medicinal
Steven R. Bowers, Dmitri K. Klimov, Christopher Lockhart
Summary: This study investigates the binding mechanism of PGLa to anionic bilayers using molecular dynamics simulations and energy calculations. The results reveal two distinct binding states of PGLa, which require helix rotation. The binding is mainly governed by desolvation and electrostatic interactions, leading to lipid redistribution and thinning of the bilayer.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2022)
Article
Biophysics
Enrico F. Semeraro, Peter Pajtinka, Lisa Marx, Ivo Kabelka, Regina Leber, Karl Lohner, Robert Vacha, Georg Pabst
Summary: This study demonstrates that equimolar mixtures of MG2a and L18W-PGLa can induce membrane curvature changes at low concentrations and promote membrane fusion by reducing the free-energy barrier for stalk formation. The membrane partitioning of L18W-PGLa increases in the presence of MG2a, but this effect diminishes at lipid concentrations higher than 1 mM, indicating that the synergistic effects observed in previous experiments with lipid concentrations >1 mM are due to peptide-induced membrane remodeling rather than their specific membrane partitioning.
BIOPHYSICAL JOURNAL
(2022)
Article
Chemistry, Physical
Aline Cisse, Arnaud Marquette, Munkhtuguldur Altangerel, Judith Peters, Burkhard Bechinger
Summary: Calorimetric and incoherent neutron scattering methods were used to investigate the effects of magainin 2 and PGLa peptides on lipid membranes mimicking those of Gram-negative bacteria. While no clear synergy between the two peptides was found, both peptides were shown to destabilize the membrane and impact its dynamics in both in-plane and out-of-plane directions.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Physical
Lisa Marx, Moritz P. K. Frewein, Enrico F. Semeraro, Gerald N. Rechberger, Karl Lohner, Lionel Porcar, Georg Pabst
Summary: The study investigated the response of asymmetric lipid membranes to interactions with various peptides, revealing differences in the impact and mechanisms of different peptides on the membranes.
FARADAY DISCUSSIONS
(2021)
Article
Immunology
Christian Mink, Erik Strandberg, Parvesh Wadhwani, Manuel N. Melo, Johannes Reichert, Irene Wacker, Miguel A. R. B. Castanho, Anne S. Ulrich
Summary: BP100 is a short, designer-made membrane-active peptide with antimicrobial, cell-penetrating, and fusogenic properties. Its amphipathic helical structure resembles that of pore forming magainin-like peptides, showing high antimicrobial activity.
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Oleg Babii, Sergii Afonin, Christian Diel, Marcel Huhn, Jennifer Dommermuth, Tim Schober, Serhii Koniev, Andrii Hrebonkin, Alexander Nesterov-Mueller, Igor V. Komarov, Anne S. Ulrich
Summary: Chemical modification of a bicyclic peptide scaffold led to the development of photoswitchable inhibitors based on diarylethene for serine protease Bos taurus trypsin 1 (T1). These inhibitors exhibited low nanomolar K-i values and a 20-fold activity modulation under irradiation. The study also demonstrated the feasibility of manipulating enzyme activity in time and space.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Nithin Suryadevara, Ansgar Pausch, Eufemio Moreno-Pineda, Asato Mizuno, Jochen Buerck, Ananya Baksi, Tim Hochdoerffer, Ivan Salitros, Anne S. Ulrich, Manfred M. Kappes, Volker Schuenemann, Wim Klopper, Mario Ruben
Summary: Enantiomerically pure Fe(II) grid complexes were successfully prepared by designing novel chiral ligands, allowing for the fabrication of magneto-chiral molecular devices. The chiral resolution of these complexes enables controlled programmable separation before synthesis. The experimental and calculated CD spectra showed good agreement, confirming the enantiomeric purity of the complexes.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Biochemistry & Molecular Biology
Parvesh Wadhwani, Saiguru Sekaran, Erik Strandberg, Jochen Burck, Archana Chugh, Anne S. Ulrich
Summary: The seven peptides from the latarcin family fold into amphiphilic alpha-helices in the presence of lipids, with different levels of aggressiveness and selectivity in antimicrobial activity. Ltc2a stands out as the most aggressive peptide, whereas Ltc1, Ltc3a, Ltc4a, and Ltc5a show efficient and selective antibacterial effects. The other two peptides, Ltc6a and Ltc7, do not have strong antimicrobial activities but can disturb model bilayers.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Polymer Science
Shouliang Nie, Karl-Friedrich Ratzsch, Stephan L. Grage, Jonas Keller, Anne S. Ulrich, Jorge Lacayo-Pineda, Manfred Wilhelm
Summary: The cross-linking process of natural rubber was studied for the first time using a combination of rheology and time-domain NMR methods. It was found that the conformational flexibility of network chains in natural rubber is affected by the efficiency of vulcanization.
Article
Chemistry, Multidisciplinary
Sergii Afonin, Serhii Koniev, Laetitia Preau, Masanari Takamiya, Alexander Strizhak, Oleg Babii, Andrii Hrebonkin, Vasyl G. Pivovarenko, Margitta Dathe, Ferdinand le Noble, Sepand Rastegar, Uwe Straehle, Anne S. Ulrich, Igor Komarov
Summary: This study successfully utilized fluorescent labeling of peptides with an amino acid bearing a fluorophore, demonstrating the importance of fluorescent labeling in studying peptide activity. The behavior of labeled peptides was observed in human cells and zebrafish embryos using various techniques.
FRONTIERS IN CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Stephan L. Grage, Sergii Afonin, Marco Ieronimo, Marina Berditsch, Parvesh Wadhwani, Anne S. Ulrich
Summary: The lateral pressure profile, an important physical property of lipid bilayers, can be manipulated and probed using peptides residing in different regions of the membrane, according to this study.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Biochemistry & Molecular Biology
Igor Komarov, Ganna Tolstanova, Halyna Kuznietsova, Natalia Dziubenko, Petro Yanchuk, Lydia Y. Shtanova, Stanislav P. Veselsky, Liudmyla Garmanchuk, Nataliia Khranovska, Oleksandr Gorbach, Taisa Dovbynchuk, Petro Borysko, Oleg Babii, Tim Schober, Anne S. Ulrich, Sergii Afonin
Summary: The study analyzed the efficacy of a photoswitchable cytotoxic peptide LMB040 on chemically induced hepatocellular carcinoma model in immunocompetent rats, finding that initial application of a less toxic form followed by in vivo photoconversion led to higher overall survival of the animals and enhanced immune response compared to untreated animals.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Beibei Meng, Stephan L. Grage, Oleg Babii, Masanari Takamiya, Neil MacKinnon, Tim Schober, Illia Hutskalov, Omar Nassar, Sergii Afonin, Serhii Koniev, Igor Komarov, Jan G. Korvink, Uwe Straehle, Anne S. Ulrich
Summary: A labeling strategy for in vivo F-19-MRI based on highly fluorinated, short hydrophilic peptide probes, is developed. These probes are functionalized further by a fluorophore and an alkyne moiety for bioconjugation. The design of the peptide probes ensures low cytotoxicity and high serum stability. The performance of these probes in F-19-MRI is demonstrated and they are found to exhibit high stability and long circulation times in living zebrafish embryos. Overall, these peptide probes are suitable for in vivo F-19-MRI applications.
Article
Biochemistry & Molecular Biology
Fabian Schweigardt, Erik Strandberg, Parvesh Wadhwani, Johannes Reichert, Jochen Buerck, Haroldo L. P. Cravo, Luisa Burger, Anne S. Ulrich
Summary: Amphipathic peptides exhibit antibiotic properties by permeabilizing cell membranes. KL peptides form amphipathic beta-strands in the presence of lipid bilayers and kill bacteria in a unique length-dependent manner. Experimental results demonstrate that KL peptides with 10-12 amino acids exhibit the best antimicrobial activity and low hemolytic side effects. The study suggests that the membrane disruption by KL peptides is achieved through a carpet mechanism.
Article
Chemistry, Physical
Frauke Greil, Rajalakshmi Punampalam, Torsten H. Walther, Stefan Heissler, Anne S. Ulrich
Summary: A novel solid phase of water stable at room temperature was believed to be accessible from hydrophilic surfaces by repeated perturbation of interfacial layers. However, a detailed biological and biochemical analysis revealed that the observed phenomena were likely due to accumulation of microbiological and organic contaminants, rather than a new solid phase of water. The same analysis also found that the presumed stable water aggregates in the lyophilized solid material consisted mainly of a conglomerate of bacteria, algae, and synthetic materials.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Meeting Abstract
Biophysics
Erik Strandberg, Fabian Schweigardt, Parvesh Wadhwani, Jochen Buerck, Anne S. Ulrich
BIOPHYSICAL JOURNAL
(2022)
Meeting Abstract
Biophysics
Parvesh Wadhwani, Saiguru Sekaran, Erik Strandberg, Jochen Burck, Archana Chugh, Anne S. Ulrich
BIOPHYSICAL JOURNAL
(2022)
Article
Chemistry, Physical
Vladimir Kubyshkin, Jochen Burck, Oleg Babii, Nediljko Budisa, Anne S. Ulrich
Summary: Circular dichroism is a conventional method for studying the secondary structures of peptides and proteins. The polyproline-II helix, while not exhibiting strictly conserved spectroscopic appearance, is significantly influenced by the surrounding solvent environment. Changes in solvation can lead to shifts and variations in the circular dichroism spectra, with new features potentially emerging in nonpolar environments. Additionally, the transition to a transmembrane state in isotropic liposomes is correlated with specific spectral changes, indicating the importance of considering the solvent environment in assessing circular dichroism spectra.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)