Article
Biochemistry & Molecular Biology
Kiryl Zhaliazka, Dmitry Kurouski
Summary: In this study, AFM-IR spectroscopy was used to investigate the secondary structure changes of A β peptide during aggregation. It was found that at the early stage, parallel β-sheet oligomers dominated, while antiparallel β-sheet oligomers appeared in the middle stage and coexisted with the parallel β-sheet fibrils at the late stage.
ACS CHEMICAL NEUROSCIENCE
(2022)
Article
Chemistry, Physical
Siddhartha Banerjee, Divya Baghel, Md Hasan Ul Iqbal, Ayanjeet Ghosh
Summary: Spontaneous aggregation of amyloid beta (Afi) proteins is a key pathological feature of Alzheimer's disease, but the structure of early-stage aggregates is not well understood. This study used atomic force microscopy-infrared nanospectroscopy to investigate the aggregation process of Afi 16-22 and found a structural transition from oligomers with parallel β-sheets to antiparallel fibrils.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Pharmacology & Pharmacy
Olga Makshakova, Liliya Bogdanova, Dzhigangir Faizullin, Diliara Khaibrakhmanova, Sufia Ziganshina, Elena Ermakova, Yuriy Zuev, Igor Sedov
Summary: This study demonstrates that certain linear anionic polysaccharides have the ability to disaggregate amyloid fibrils and promote protein renaturation. These findings contribute to our understanding of the mechanism of amyloid disaggregation and provide a foundation for the development of new therapeutic agents for amyloidosis treatment and the design of novel functional protein-polysaccharide complex-based nanomaterials.
Article
Biochemistry & Molecular Biology
Pauline Cornette, Ilhem Lilia Jaabar, Vincent Dupres, Jean-David Werthel, Francis Berenbaum, Xavier Houard, Jessem Landoulsi, Geoffroy Nourissat
Summary: The study investigated the effect of crosslinking treatment on the structure and mechanical properties of diseased human shoulder capsules. The results showed that the crosslinking procedure changed the biomechanics of the capsules while keeping their structural organization unchanged at the single fibril level. This procedure may be a promising way to preserve the functions of collagen-based tissues and tune their elasticity for clinically relevant treatments.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Yongxiu Song, Bin Dai, Yong Wang, Yin Wang, Cong Liu, Pontus Gourdon, Lei Liu, Kaituo Wang, Mingdong Dong
Summary: This study used atomic force microscopy, cryo-electron microscopy, and molecular dynamics simulation to explore the molecular mechanism of amyloid peptide aggregation. The study discovered the role of helical fibrillar structure and hetero-zipper beta-sheet in peptide assembly, as well as the significance of hydrophobic core and hydrophilic area.
Article
Chemistry, Analytical
M. Seray Ural, Emmanuel Dartois, Jeremie Mathurin, Didier Desmaele, Philippe Collery, Alexandre Dazzi, Ariane Deniset-Besseau, Ruxandra Gref
Summary: Researchers have successfully characterized individual nanoparticles using atomic force microscopy-infrared spectroscopy (AFM-IR) and proposed a label-free quantification method to estimate drug loadings. This research is of great significance for quality control in nanomedicine.
Article
Biotechnology & Applied Microbiology
Jerome F. L. Duval, Angelina Razafitianamaharavo, Isabelle Bihannic, Marc Offroy, Nicolas Lesniewska, Benedicte Sohm, Helene Le Cordier, Christian Mustin, Christophe Pagnout, Audrey Beaussart
Summary: The variation of cell-wall ultrastructure, composition, and nanomechanics of Chlorella vulgaris upon culture ageing and lysozyme treatment was investigated using a combination of atomic force microscopy (AFM) and confocal microscopy. The presence of a fibrillated mesh at the surface of cells harvested in the stationary phase was observed through AFM imaging. The structured network formed by fibrils containing the N-acetyl-D-glucosamine unit was severely damaged by lysozyme treatment. Furthermore, lysozyme was found to affect algal physiology, triggering oxidative stress and changes in cell lipid content.
ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
(2023)
Article
Chemistry, Multidisciplinary
Kordula B. Schnabl, Laurens D. B. Mandemaker, Klaas G. J. Nierop, Olivier V. B. Deen, Desmond D. Eefting, Ina Vollmer, Bert M. Weckhuysen
Summary: Research shows that chitosan, a strong and workable derivative of chitin obtained from crustaceans, can be used as a renewable alternative to fossil-fuel-based polymer materials. By adding different types of green additives, chitosan-based composites with various properties, from very hard and brittle to soft and flexible, have been successfully produced. These findings open up possibilities for adjusting the properties of chitosan-based polymer materials and applying them in consumer goods.
Article
Nanoscience & Nanotechnology
Keivan Asadi, Junghoon Yeom, Hanna Cho
Summary: Investigating internal resonance (IR) mechanisms in micro/nanoresonators reveals that intermodal coupling between second and third flexural modes in asymmetric structures provides an optimal condition for strong IR, with high energy transfer to the resonated mode. This study introduces design strategies that can be easily integrated into typical micro/nanoelectromechanical systems, offering potential for paradigm-shifting applications in micro/nanosystems.
MICROSYSTEMS & NANOENGINEERING
(2021)
Article
Chemistry, Physical
Wanhao Cai, Duo Xu, Fa Zhang, Junhao Wei, Song Lu, Linmao Qian, Zhongyuan Lu, Shuxun Cui
Summary: This study investigates the strength of hydrogen bonds in a model system under interference-free conditions and finds that the bond is significantly weakened or even broken in liquid environments compared to vacuum. The results suggest that the strength of hydrogen bonds measured in vacuum can serve as a standard value for future studies. This approach provides fundamental insights into nanostructures and materials involving hydrogen bonds in different environments.
Article
Chemistry, Applied
Nemanja Mijin, Jelica Milosevic, Sanja Stevanovic, Predrag Petrovic, Aleksandar Lolic, Tomaz Urbic, Natalija Polovic
Summary: The aggregation of proteins into fibrillar, amyloid-like aggregates has positive effects on various technological properties of food products. Heavy metal ions, such as lead and cadmium, can influence this aggregation process and alter the morphology of the aggregates. This study investigated the impact of lead and cadmium ions on the aggregation of ovalbumin, a model protein, under high temperature and acidic conditions. The results demonstrated that the binding of these metal ions to ovalbumin affected the structure and morphology of the resulting amyloid-like aggregates.
FOOD HYDROCOLLOIDS
(2023)
Article
Materials Science, Multidisciplinary
Saeid Ekrami, Fabienne Quiles, Alice Schollhammer, Xavier Bellanger, Erwan Andre, Gregory Francius
Summary: In this study, the cross-linking reactions of hydrogels based on PAH and HA were examined. It was found that the choice of cross-linkers can significantly affect the mechanical and chemical properties of the hydrogels.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Food Science & Technology
Sonu Sharma, Kshanaprava Dhalsamant, Punyadarshini Punam Tripathy, Raj Kumar Manepally
Summary: The study compared the effects of hot air drying and direct solar drying on turmeric, finding that direct solar drying resulted in faster drying rates, better color retention, smoother surface, and brighter color compared to hot air drying.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2021)
Editorial Material
Multidisciplinary Sciences
Telmo O. Paiva, Albertus Viljoen, Yves F. Dufrene
Summary: Advancements in atomic force microscopy (AFM) techniques and methodologies in microbiology have enhanced our understanding of microbial cell surfaces. Recent studies have shown that AFM imaging of cells and membranes at or near molecular resolution enables detailed visualization of membrane-drug interactions.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Seth Kenkel, Mark Gryka, Lin Chen, Matthew P. Confer, Anirudha Rao, Scott Robinson, Kannanganattu V. Prasanth, Rohit Bhargava
Summary: Nearfield spectroscopic imaging techniques can be a powerful tool to simultaneously map cellular ultrastructure and molecular composition, but their current capabilities are limited. This study proposes an instrument design that combines null-deflection measurements with resonance enhancement to achieve high-sensitivity nanoscale infrared imaging. Experimental results using cellular acini samples demonstrate the ability of this method to easily record high-quality chemical imaging data.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Microbiology
Buu Minh Tran, Haritha Prabha, Aditya Iyer, Conor O'Byrne, Tjakko Abee, Bert Poolman
Summary: The study determined the lateral diffusion coefficient of GFP in Listeria monocytogenes under different conditions, finding that it was less affected by hyperosmotic stress compared to other bacteria. Additionally, a temperature optimum for protein diffusion was identified at 30 degrees C in L. monocytogenes, suggesting variations in cytoplasm structure and macromolecular crowding with temperature changes. The findings were discussed in relation to how L. monocytogenes survives during environmental transmission and interaction with the human host.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Biophysics
James D. Pickering, Mikkel Bregnhoj, Adam S. Chatterley, Mette H. Rasmussen, Steven J. Roeters, Kris Strunge, Tobias Weidner
Summary: This article provides a detailed description of designing and constructing a broadband VSFG spectrometer, along with specific instrument details often omitted in other descriptions. It is valuable for newcomers to the field.
Article
Chemistry, Physical
S. Strazdaite, S. J. Roeters, A. Sakalauskas, T. Sneideris, J. Kirschner, K. B. Pedersen, B. Schiott, F. Jensen, T. Weidner, V Smirnovas, G. Niaura
Summary: The study investigated the interactions between model lipid monolayers and Aβ in different states using surface-sensitive vibrational sum-frequency generation (VSFG) spectroscopy. The results showed that the interaction between Aβ aggregates and lipid monolayers depended on the structure of the aggregates and the type of lipid layer, with a correlation between the amide-II' signal and the degree of amyloid aggregates.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Physical
Steven J. Roeters, Rolf Mertig, Helmut Lutz, Adrienne Roehrich, Gary Drobny, Tobias Weidner
Summary: The silaffin peptide R5 plays a crucial role in the biogenesis of diatom silica cell walls, offering potential applications in biotechnology, drug development, and materials science. Researchers have combined experimental data with theoretical calculations to elucidate the conformation of R5 within silica particles and its structural transition when interacting with silica precursors.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Kayla Sprenger, Steven J. Roeters, Sergio Mauri, Rolf Mertig, Yoshiharu Nishiyama, Jim Pfaendtner, Tobias Weidner
Summary: Engineers have been designing new cellulase enzymes for the conversion of biomass into green fuels and chemicals, with a critical factor being the attachment via the enzyme's carbohydrate binding module (CBM). Experimental data and molecular dynamics simulations show that binding is driven by hydrogen bonding and that tyrosine side chains within the CBM align the cellulase with the registry of the cellulose surface. This alignment is favorable for the translocation and effective cellulose breakdown, likely an important parameter for the design of novel enzymes.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Multidisciplinary
L. Schmuser, M. Trefz, S. J. Roeters, W. Beckner, J. Pfaendtner, D. Otzen, S. Woutersen, M. Bonn, D. Schneider, T. Weidner
Summary: High-resolution structural information of membrane proteins is crucial for cell biology and drug design, with XRD structures showing differences compared to the in situ structure of GlpF.
Article
Chemistry, Physical
Mikkel Bregnhoj, Steven J. Roeters, Adam S. Chatterley, Fani Madzharova, Rolf Mertig, Jan Skov Pedersen, Tobias Weidner
Summary: This study reports on the secondary structure and orientation of the S1 segment of the SARS-CoV-2 spike protein at the air-water interface. The results show that the S1 segment remains folded at this interface and predominantly binds as a monomer.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Chemistry, Physical
Mikkel Bregnhoj, Helmut Lutz, Steven J. Roeters, Ingo Lieberwirth, Rolf Mertig, Tobias Weidner
Summary: Diatoms use silaffin peptides to synthesize titanium dioxide nanoparticles, providing an environmentally friendly approach for the production of nanomaterials with potential applications in water splitting and biocompatible materials design. The study demonstrates that the silaffin peptide R5 can precipitate stable titanium dioxide sheets.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Kris Strunge, Nina Hoinkis, Helmut Lutz, Sarah Alamdari, Steven J. Roeters, Hao Lu, Jim Pfaendtner, Tobias Weidner
Summary: This study demonstrates the successful catalysis of nanometer thin and stable sheets of silicon dioxide and titanium dioxide using a peptide mimic based on the catalytic triad of the marine sponge protein silicatein.
Article
Biology
Nasar Khan, Husnu Aslan, Henning Buettner, Holger Rohde, Thaddeus Wayne Golbek, Steven Joop Roeters, Sander Woutersen, Tobias Weidner, Rikke Louise Meyer
Summary: Staphylococcus epidermidis causes difficult-to-treat clinical infections by forming biofilms on the surface of medical implants. The bacteria's ability to adhere to the surface is facilitated by the giant adhesive protein, extracellular matrix-binding protein (Embp), which specifically binds to fibrillated fibronectin on surfaces. This newly identified attachment mechanism is critical for colonization of intravascular devices and may be deployed by other biofilm-forming pathogens.
Article
Biochemistry & Molecular Biology
Giulia Giubertoni, Federico Caporaletti, Steven J. Roeters, Adam S. Chatterley, Tobias Weidner, Peter Laity, Chris Holland, Sander Woutersen
Summary: The mechanical properties of biomaterials are influenced by the interactions and conformations of their protein building blocks. Infrared spectroscopy is a commonly used method for studying molecular structures, and polarized two-dimensional infrared spectroscopy (2D-IR) is applied in this study to identify the protein secondary structures in native silk films. The results show changes in the secondary structure due to hydration, with an increase in random coil content and a decrease in helical content.
Article
Chemistry, Physical
Andrew P. Carpenter, Patricia Khuu, Tobias Weidner, Colin P. Johnson, Steven J. Roeters, Joe E. Baio
Summary: Dysferlin is a critical protein involved in repairing muscle injuries by recruiting vesicles to the injured site. Studies show that its N-terminal C2A domain can change its binding orientation based on the lipid composition of the membrane.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Review
Neurosciences
Aditya Iyer, Arshdeep Sidhu, Vinod Subramaniam
Summary: N-alpha-acetylation is a common post-translational modification in eukaryotic proteins, which has significant effects on protein regulation and function. However, the precise mechanisms and implications of N-alpha-acetylation of alpha-synuclein (alpha S) are not fully understood. This review provides an overview of current knowledge and discusses the impact of N-alpha-acetylation on the conformational, oligomeric, and fibrillar states of alpha S, as well as its relevance to Lewy body formation and synucleinopathies.
FRONTIERS IN NEUROSCIENCE
(2022)
Article
Multidisciplinary Sciences
Steven J. Roeters, Kris Strunge, Kasper B. Pedersen, Thaddeus W. Golbek, Mikkel Bregnhoj, Yuge Zhang, Yin Wang, Mingdong Dong, Janni Nielsen, Daniel E. Otzen, Birgit Schiott, Tobias Weidner
Summary: This study reports a mechanism explaining why lipid membranes catalyze the formation of harmful aggregates at elevated concentrations.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Andrew P. Carpenter, Patricia Khuu, Tobias Weidner, Colin P. Johnson, Steven J. Roeters, Joe E. Baio
Summary: Dysferlin plays a critical role in muscle membrane repair by recruiting vesicles to the injured site. Research shows that its binding orientation is influenced by the lipid composition of the membrane.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
