Article
Chemistry, Multidisciplinary
Shogo Okuda, Naoki Ousaka, Takuya Iwata, Riku Ishida, Akio Urushima, Nozomu Suzuki, Shusaku Nagano, Tomoyuki Ikai, Eiji Yashima
Summary: In this study, unique coordination-driven supramolecular helical assemblies were reported using specific dirhodium complexes and auxiliary materials to form helical polymers in solvents. These structures are stabilized by hydrogen bonding networks and exhibit specific chirality and helical sense inversion properties during formation.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Chemistry, Multidisciplinary
Romain Costil, Mira Holzheimer, Stefano Crespi, Nadja A. Simeth, Ben L. Feringa
Summary: Molecular photoactuators can control the shape and properties of responsive systems through supramolecular interactions, allowing work to be done at micro- and macroscopic scales. Stereochmical cascades within photoresponsive structures can amplify motion to distant components, offering potential in designing the smallest imaginable machines.
Article
Chemistry, Multidisciplinary
Francisco Rey-Tarrio, Santiago Guisan-Ceinos, Juan M. Cuerva, Delia Miguel, Maria Ribagorda, Emilio Quinoa, Felix Freire
Summary: This study demonstrates the direct relationship between photochemical degradation in PPAs and their dynamic helical behavior. It suggests the possibility of improving photostability by designing PPAs with quasi-static helical behavior.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Green & Sustainable Science & Technology
Haci Parlamis, Ekrem Ozden, Mahmut Sami Buker
Summary: Experimental testing of a PTAC with helical screw tape insertion showed significant improvement in efficiency and heat transfer performance. The temperature rise improvement ranged from 56% to 71%, validating the potential of helical screw tape insert in enhancing heat exchange.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2021)
Article
Biochemistry & Molecular Biology
Matthias Gloegl, Nikolas Friedrich, Gabriele Cerutti, Thomas Lemmin, Young D. Kwon, Jason Gorman, Liridona Maliqi, Peer R. E. Mittl, Maria C. Hesselman, Daniel Schmidt, Jacqueline Weber, Caio Foulkes, Adam S. Dingens, Tatsiana Bylund, Adam S. Olia, Raffaello Verardi, Thomas Reinberg, Nicolas S. Baumann, Peter Rusert, Birgit Dreier, Lawrence Shapiro, Peter D. Kwong, Andreas Plueckthun, Alexandra Trkola
Summary: The authors utilized DARPin technology to produce broadly neutralizing inhibitors that target a region of V3 which becomes accessible after binding to the CD4 receptor, demonstrating the essential role of V3 in viral entry.
NATURE STRUCTURAL & MOLECULAR BIOLOGY
(2023)
Article
Biophysics
Kirk E. Bassett, Steven K. Charles, Dustin A. Bruening
Summary: A novel Signed Helical Angle (SHA) method was developed to quantify midfoot angular displacement, providing a more accurate characterization of its non-planar nature. The SHA method showed a larger range of motion compared to other techniques, offering an intuitive and useful method to analyze midfoot motion.
JOURNAL OF BIOMECHANICS
(2023)
Article
Chemistry, Multidisciplinary
Li Zhou, Xun-Hui Xu, Zhi-Qiang Jiang, Lei Xu, Ben-Fa Chu, Na Liu, Zong-Quan Wu
Summary: Inspired by natural helices, this study focused on the fabrication of helical materials with controlled handedness. It was found that helices of opposite handedness exhibited different activity, with the unfavored handedness being self-terminated and the favored handedness showing high activity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Thermodynamics
Hrishiraj Ranjan, Sujoy Kumar Saha
Summary: This study numerically investigates the hydro-thermal characteristics of transverse ribs combined with helical screw tape inserts in square duct and compares the findings with limited experimental results. The results show that the present configuration produces good mixing and enhanced boundary layer separation. The Nusselt number and friction factor increase with an increase in rib height and Reynolds number, while they decrease with an increase in rib pitch and screw tape parameter value.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2022)
Article
Chemistry, Multidisciplinary
Shoma Ikeda, Ryohei Takeda, Takaya Fujie, Naoto Ariki, Yuuya Nagata, Michinori Suginome
Summary: This study demonstrates the dynamic induction of single-handed helical conformation in polymers bearing only achiral substituents by utilizing chiral additives in achiral solvents. The new mode of screw-sense induction has led to the successful induction of homochiral screw-sense in virtually achiral polymers, enabling highly enantioselective reactions with up to 95% enantiomeric excess.
Article
Multidisciplinary Sciences
Francisco Rey- Tarrio, Emilio Quinoa, Gustavo Fernandez, Felix Freire
Summary: A unique multi-helical material combining information from metallosupramolecular and covalent helical polymers is presented. The helical structure of the poly(acetylene) backbone guides the pendant groups in a way that generates a tilting degree and forms a multi-chiral material.
NATURE COMMUNICATIONS
(2023)
Article
Polymer Science
Joshua Selby, Marco Holzapfel, Krzysztof Radacki, Asim Kumar Swain, Holger Braunschweig, Christoph Lambert
Summary: This study investigates the influence of chirality on the structure and properties of cisoid indolenine squaraine polymers with different side chains. The absorption spectroscopy and circular dichroism results show that the behavior of the polymers is strongly dependent on the solvent and the type of side chains. The temperature-dependent absorption spectroscopy reveals the thermodynamic parameters of helix folding and suggests that increasing the steric demand of the side chains leads to an increase in entropy and enthalpy. Fluorescence spectroscopy confirms the structural characteristics of the polymers.
Article
Engineering, Civil
Reza Hoseinpour, Mohsen Keramati, Cristina de Hollanda Cavalcanti Tsuha
Summary: This study investigates the impact of adding a second helix to a single-helix pile on foundation performance in sandy soils. The results show that in dense sand, the bearing pressure mobilized by the pile helices in tension is higher than in compression. Additionally, the addition of a second helix increases the capacity for both tensile and compressive loading, with a higher gain observed in tensile capacity.
INTERNATIONAL JOURNAL OF CIVIL ENGINEERING
(2023)
Article
Chemistry, Organic
David P. Tilly, Catherine McColl, Mingda Hu, Inigo J. Vitorica-Yrezabal, Simon J. Webb
Summary: This article describes the study of two short pentapeptides rich in alpha-aminoisobutyric acid (Aib) as enantioselective organocatalysts. The findings show that folding into a 310 helical structure allows the peptides to transmit chiral information and promote the enantioselectivity of the reaction. This demonstrates the important role of achiral residues in catalysis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Green & Sustainable Science & Technology
Reza Roohi, Amir Arya, Masoud Akbari, Mohammad Javad Amiri
Summary: Improving the performance of renewable energy harvesters is crucial and complex. Parabolic solar collectors are considered one of the most promising and commonly used devices among renewable energy harvesters. Researchers are focusing on optimizing the performance of Parabolic Trough Collectors (PTCs), including increasing the heat flux absorption by the absorber tubes. The implementation of helical screw tape (HST) and nanofluids has proven to be effective in overcoming this issue.
Article
Chemistry, Physical
Congxu Xuan, Xinyu Li, Zhun Wang, Hao Wu, Tao Tang, Jianfeng Wen, Ming Li, Jianrong Xiao
Summary: The strategy of embedding PANI into RGO/HCNT skeleton was designed to prepare a high-performance supercapacitor with remarkable gravimetric capacitance and cycling stability. The assembled flexible SC based on CRCP showed considerable electrochemical performance with high specific capacitance and energy density at 1A g(-1), while maintaining good performance stability at large bending angles.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Qi Lin, Hao Lan, Chunmiao Ma, Ryan T. Stendall, Kenneth Shankland, Rebecca A. Musgrave, Peter N. Horton, Carsten Baldauf, Hans-Joerg Hofmann, Craig P. Butts, Manuel M. Mueller, Alexander J. A. Cobb
Summary: We present the first structures of an unusual helix formed by a heteromeric sequence of alpha- and delta-amino acids and demonstrate its application in catalysis. The helix formation is driven by intramolecular hydrogen bonds, but we also observed an apolar interaction that stabilizes one type of helix over another. This unique stabilization enables the alpha-residues to engage in bifunctional catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Lydia I. Dewis, Madhavachary Rudrakshula, Christopher Williams, Elisabetta Chiarparin, Eddie L. Myers, Craig P. Butts, Varinder K. Aggarwal
Summary: Using α-helix mimetics as inhibitors of protein-protein interactions is a prevalent therapeutic strategy. Controlling the conformation of mimetics through destabilizing syn-pentane interactions can enhance their efficacy.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Medicinal
Crescenzo Coppa, Andrea Bazzoli, Maral Barkhordari, Alessandro Contini
Summary: This study evaluated the performance of accelerated molecular dynamics (aMD) protocols in predicting the secondary structure of eight peptides, including helical, fi-hairpin, and disordered peptides. The results showed that all three combinations of force fields and solvation models performed well on helical peptides. For fi-hairpins, the ff19SB force field combined with both solvation methods showed good performance, with a slight preference for the TIP3P solvation model. The ff19SB/OPC combination exhibited the best performance on intrinsically disordered peptides. However, the ff14SB/TIP3P combination had a strong bias towards helical peptides.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2023)
Article
Multidisciplinary Sciences
David P. Tilly, Jean-Paul Heeb, Simon J. Webb, Jonathan Clayden
Summary: Molecular biology controls complex reaction networks by translating a chemical input into an orthogonal chemical output, but dynamic foldamers have been limited by stereochenical changes that produce spectroscopic signals. In this study, the authors introduce an artificial molecular translation device that converts a chemical input into an unrelated chemical output. This device modulates the reactivity of an imidazole moiety by the presence of chloride ions through the allosteric remote control of imidazole tautomer states.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Luis Martinez-Crespo, Inigo J. Vitorica-Yrezabal, George F. S. Whitehead, Simon J. Webb
Summary: Relaying conformational change over several nanometers is crucial in allosterically regulated proteins. Scientists have successfully replicated this mechanism using nanometer-sized molecules that can reversibly switch between defined shapes in response to signaling molecules. The study demonstrated that a 1.8 nm long rigid rod molecule can serve as a switchable multi-squaramide hydrogen-bond relay, with each relay adopting different orientations based on proton signals and undergoing reversible changes. Additionally, a chemical fuel acted as a dissipative signal, causing the relay to return to its original orientation when consumed.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Microbiology
Mickael Guerin, Marc Shawky, Ahed Zedan, Stephane Octave, Berangere Avalle, Irene Maffucci, Severine Padiolleau-Lefevre
Summary: With a high number of cases each year, Lyme borreliosis (LB) is the most common tick-borne illness in the world. The diagnosis of LB is controversial and relies on an indirect approach with low sensitivity. Early and proper detection is crucial for effective treatment and preventing the persistence of the pathogen. This review focuses on improving the current diagnosis and innovative methods for more accurate detection of LB.
Article
Chemistry, Multidisciplinary
David P. Tilly, David T. J. Morris, Jonathan Clayden
Summary: In this study, it was discovered that the ethylene-bridged hydrogen-bonded urea oligomer linear chain has reversible anion coordination and cascade conformational changes. The polarity reversals of hydrogen bonds in the oligomer propagate, resulting in a global switch of hydrogen-bond directionality. This induces a change in emission and excitation wavelengths of a fluorophore at the opposite terminus. Consequently, the molecule acts as a chemical sensor with a relayed remote spectroscopic response to varying anion concentrations. The anion-induced polarity switch provides an artificial communication mechanism for conveying information through oligomeric structures.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
David T. J. Morris, Steven M. Wales, Javier Echavarren, Matej Zabka, Giulia Marsico, John W. Ward, Natalie E. Pridmore, Jonathan Clayden
Summary: Cyclic triureas derived from TACN were synthesized and characterized. Dynamic cyclochirality was observed, with the hydrogen-bonded urea groups exchanging enantiomers through bowl inversion and directionality reversal. Structural modifications were found to affect the enantiomerization barrier, resulting in a planar-chiral, atropisomeric bowl-shaped structure with high stereochemical stability solely from its hydrogen-bonding network.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemical Research Methods
Jean-Paul Heeb, Jonathan Clayden, Martin D. Smith, Roly J. Armstrong
Summary: This article describes three experimental methods, namely kinetic analysis, dynamic HPLC, and variable-temperature NMR, for measuring the rate of racemization in atropisomers. Atropisomers are molecules that exhibit stereochemistry from restricted bond rotation and are highly relevant in catalysis, medicine, and materials science. The methods presented in this article provide techniques for evaluating the configurational stability of atropisomeric molecules and can be performed using standard analytical equipment. The article also discusses the selection of a suitable method for determining racemization rates for new molecular structures with unknown properties.
Article
Chemistry, Organic
Marta Papis, Raffaella Bucci, Alessandro Contini, Maria Luisa Gelmi, Leonardo Lo Presti, Giovanni Poli, Gianluigi Broggini, Camilla Loro
Summary: A phosphine-catalyzed domino assembly of six units of 2-bromomethyl acrylates was developed to synthesize polyalkenyl adducts containing two cyclohexenyl rings. This method involves initial dimerization and subsequent trimerization of the substrate, resulting in the formation of seven carbon-carbon bonds and four stereocenters. The protocol has also been successfully scaled up to gram-scale experiments.
Article
Biochemical Research Methods
Thomas Binet, Berangere Avalle, Miraine Davila Felipe, Irene Maffucci
Summary: AptaMat, a simple and sensitive algorithm, has been developed for comparing the secondary structures of single-stranded nucleic acids (ssNAs). It outperforms other commonly used metrics in discriminating similar structures and correctly classifying RFAM families during clustering.
Article
Chemistry, Physical
Hussain A. Al Nasser, Luis Martinez-Crespo, Simon J. Webb, Robert A. W. Dryfe
Summary: Thiourea-based receptors’ binding affinity for anions at the aqueous|organic interface was evaluated using electrochemical measurements. Most anions showed a 1:1 stoichiometry for complexation, except for excess Cl- and Br- anions which exhibited higher stoichiometry. High stability constants were observed at the aqueous|1,2-dichlorobenzene (DCB) interface, possibly due to the less competitive environment of the less polar solvent. Protonation of the receptor at the bridgehead tertiary amine was inferred from potential-dependent voltammetric measurements unrelated to anion:receptor complexation.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Review
Chemistry, Multidisciplinary
David T. J. Morris, Jonathan Clayden
Summary: Biological systems and foldamer chemistry both exploit the propagation of conformational change to communicate information on the molecular scale. Switchable screw-sense preference is a communication mechanism that utilizes dynamic helical foldamers to transmit information. This review discusses the functional requirements for communication devices and describes the use of various stimuli to switch the screw sense. It also explores how conformational switching can control chemical events remote from the source of information.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Organic
David P. Tilly, Catherine McColl, Mingda Hu, Inigo J. Vitorica-Yrezabal, Simon J. Webb
Summary: This article describes the study of two short pentapeptides rich in alpha-aminoisobutyric acid (Aib) as enantioselective organocatalysts. The findings show that folding into a 310 helical structure allows the peptides to transmit chiral information and promote the enantioselectivity of the reaction. This demonstrates the important role of achiral residues in catalysis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Alexander M. Prophet, Kritanjan Polley, Gary J. Van Berkel, David T. Limmer, Kevin R. Wilson
Summary: The oxidation kinetics of iodide by ozone at the air-water interface is studied in single microdroplets. Molecular simulations and kinetic modeling are used to understand the underlying multiphase mechanism.
Article
Chemistry, Multidisciplinary
Rong Zhang, Jiajing Lan, Fei Wang, Shumei Chen, Jian Zhang
Summary: By utilizing 1,1'-ferrocene dicarboxylic acid as a chelating and surface protection ligand, we have synthesized multi-nuclear indium oxide clusters with varying nuclear sizes, including heptanuclear and thirteen-nuclear clusters. These clusters possess labile coordination sites, allowing for structural modification and self-assembly, resulting in the formation of various cluster structures.
Article
Chemistry, Multidisciplinary
Hui Wang, Hui Liu, Mingsen Wang, Jiaheng Hou, Yongjun Li, Yuancheng Wang, Yingjie Zhao
Summary: Two supramolecular complexes were prepared using CBs and M1, and their single-crystal structures were analyzed by SCXRD. The unexpected 1:2 self-assembly structure between M1 and CB[8] was discovered for the first time. These complexes exhibit unique photophysical properties and provide valuable information about the structure and photophysical properties of supramolecular complexes.
Article
Chemistry, Multidisciplinary
Chang-Hee Lee, Sookil Park, Sanggil Kim, Ji Young Hyun, Hyun Soo Lee, Injae Shin
Summary: The epidermal growth factor receptor (EGFR) is a cell-surface glycoprotein involved in cell proliferation and tumor development. This study used a fluorescently labeled EGFR to investigate its time-dependent endocytosis in live cells and found that appended glycans affect EGFR internalization. Additionally, the study detected sialic acid residues attached to EGFR on the live cell surface using FRET-based imaging. This research provides valuable insights into the cellular functions of EGFR.
Article
Chemistry, Multidisciplinary
Subhankar Sahu, Lokesh Kumar, Sumita Das, Dipti Gupta, Ruchi Anand
Summary: This study proposes a strategy that combines organic electronics with biosensor scaffolds to create a compact device for monitoring environmental aromatic pollution. By coupling biosensing protein MopR with an organic electrochemical transistor (OECT), a sensor module capable of efficient detection of phenol was designed. Exclusive phenol detection with minimal loss of sensitivity could be achieved in complex pollutant mixtures and real environmental samples.
Review
Chemistry, Multidisciplinary
Changseok Lee, Hyung-Joon Kang, Sungwoo Hong
Summary: The formation of C-N bonds through hydroamination reactions catalyzed by nickel hydrides has been a topic of recent interest. This approach offers a way to efficiently transform a variety of alkene and alkyne substrates into compounds enriched with C-N bonds. The review provides a concise overview of the underlying reaction mechanisms and aims to stimulate further progress in NiH-catalytic techniques and catalyst design.
Article
Chemistry, Multidisciplinary
Yueci Wu, Lu-Lu Sun, Hai-Hao Han, Xiao-Peng He, Weiguo Cao, Tony D. James
Summary: Drug-induced liver injury (DILI) is a common cause of acute liver failure in the USA and Europe, but most cases can be recovered or prevented by discontinuing the offending drug. Recent research has found that peroxynitrite (ONOO-) can be used as a potential indicator for early diagnosis of DILI, and there is an urgent need to establish a method to detect and track peroxynitrite in DILI cases. In this study, a FRET-based nano fluorescent probe CD-N-I was developed, which showed high selectivity and sensitivity in detecting peroxynitrite. The probe successfully detected exogenous peroxynitrite in live cells and endogenous peroxynitrite in APAP-induced liver injury of HepG2 cells.
Article
Chemistry, Multidisciplinary
Dmitry L. Lipilin, Mikhail O. Zubkov, Mikhail D. Kosobokov, Alexander D. Dilman
Summary: This article describes a direct photocatalytic method for the thiolation of unprotected acids, which was previously challenging. By using a thionocarbonate reagent with an N-O bond, the efficient conversion of carboxylic acids to thiols is achieved.
Article
Chemistry, Multidisciplinary
Jason Malenfant, Lucille Kuster, Yohann Gagne, Kouassi Signo, Maxime Denis, Sylvain Canesi, Mathieu Frenette
Summary: Raman microscopy can reveal compound-specific vibrational fingerprints without sample preparation. The combination of efficient theoretical calculations and a user-friendly software can accurately predict peak positions and provide match scores to assist with structure determination.
Article
Chemistry, Multidisciplinary
Jayoh A. Hernandez, Paul S. Micus, Sean Alec Lois Sunga, Luca Mazzei, Stefano Ciurli, Gabriele Meloni
Summary: Essential trace metals play crucial roles in the survival and virulence of bacterial pathogens. Helicobacter pylori requires nickel for colonization and persistence in the stomach, and NixA is an essential nickel transporter in this process. This study characterizes the selectivity and electrogenic nature of NixA-mediated nickel transport.
Article
Chemistry, Multidisciplinary
Tarali Devi, Kuheli Dutta, Jennifer Deutscher, Stefan Mebs, Uwe Kuhlmann, Michael Haumann, Beatrice Cula, Holger Dau, Peter Hildebrandt, Kallol Ray
Summary: This study emphasizes the importance of subtle electronic changes and secondary interactions in the stability of biologically relevant metal-dioxygen intermediates. It also shows that the role of the chloride ligand in stabilizing the Fe-III-(OOBu)-Bu-t moiety can extend to other anions, including the thiolate ligand.
Article
Chemistry, Multidisciplinary
Jacqueline R. Santhouse, Jeremy M. G. Leung, Lillian T. Chong, W. Seth Horne
Summary: By studying the folding kinetics and mechanism of the BdpA sequence, researchers found that altering the backbone connectivity can affect protein folding. This suggests that protein mimetic chains have a significant degree of plasticity in transitioning between unfolded and folded states.
Article
Chemistry, Multidisciplinary
Divanshu Gupta, Ralf Einholz, Holger F. Bettinger
Summary: This study presents the first direct spectroscopic evidence of a cyclic seven-membered iminoborane. Compared to linear amino-iminoboranes, this cyclic iminoborane exhibits weakened bond strength and lower Lewis acidity value. The study suggests that the reduced ring strain of cyclic iminoborane prevents nitrogen fixation but allows facile (2 + 2) cycloaddition reaction with C2H4.
Article
Chemistry, Multidisciplinary
Renny Mathew, Aniruddha Mazumder, Praveen Kumar, Julie Matula, Sharmarke Mohamed, Petr Brazda, Mahesh Hariharan, Brijith Thomas
Summary: This study reveals the packing arrangement of partially disordered nitro-perylenediimide (NO2-PDI) using a synergistic approach that combines 3D ED, ssNMR, and DFT techniques. By overcoming these challenges, this methodology opens up new avenues for material characterization, driving exciting advancements in the field.