bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conformational Dynamics, Energetics, and the Divergent Evolution of Allosteric Regulation: The Case of the Yeast MAPK Family
Authors: Guarra Federica , Colombo Giorgio 
Published: May 2024

AbstractAllosteric mechanisms provide finely‐tuned control over signalling proteins. Proteins of the same family may share high sequence identity and structural similarity but show distinct traits of allosteric control and evolutionary divergent regulation. Revealing the determinants of such properties may be important to understand the molecular bases of different regulatory pathways. Herein, we investigate whether and how evolutionarily‐divergent traits of allosteric regulation in homologous proteins can be decoded in terms of internal dynamics and interaction networks that support functionally oriented conformations. In this framework, we start from the comparative analysis of the dynamics and energetics of the yeast MAP Kinases (MAPKs) Fus3 and Kss1 in their native basins. Importantly, distinctive dynamic and energetic stabilization features emerge, which can be related to the two proteins’ differential ability to be phosphorylated and engage with the allosteric activator Ste5. We then expanded our study to other evolutionarily‐related MAPKs. We show that the dynamical and energetical traits defining the distinct regulatory profiles of Fus3 and Kss1 can be traced along their evolutionary tree. Overall, our approach is able to reconnect (latent) allostery with the principal elements of protein structural stabilization and dynamics, showing how allosteric regulation was encrypted in MAPKs structure well before Ste5 appearance.
The Dynamic Plasticity of P. aeruginosa CueR Copper Transcription Factor upon Cofactor and DNA Binding
Authors: Yasin Ameer , Mandato Alysia , Hofmann Lukas , Igbaria‐Jaber Yasmin , Shenberger Yulia , Gevorkyan‐Airapetov Lada , Saxena Sunil , Ruthstein Sharon 
Published: May 2024

AbstractBacteria use specialized proteins, like transcription factors, to rapidly control metal ion balance. CueR is a Gram‐negative bacterial copper regulator. The structure of E. coli CueR complexed with Cu(I) and DNA was published, since then many studies have shed light on its function. However, P. aeruginosa CueR, which shows high sequence similarity to E. coli CueR, has been less studied. Here, we applied room‐temperature electron paramagnetic resonance (EPR) measurements to explore changes in dynamics of P. aeruginosa CueR in dependency of copper concentrations and interaction with two different DNA promoter regions. We showed that P. aeruginosa CueR is less dynamic than the E. coli CueR protein and exhibits much higher sensitivity to DNA binding as compared to its E. coli CueR homolog. Moreover, a difference in dynamical behavior was observed when P. aeruginosa CueR binds to the copZ2 DNA promoter sequence compared to the mexPQ‐opmE promoter sequence. Such dynamical differences may affect the expression levels of CopZ2 and MexPQ‐OpmE proteins in P. aeruginosa. Overall, such comparative measurements of protein‐DNA complexes derived from different bacterial systems reveal insights about how structural and dynamical differences between two highly homologous proteins lead to quite different DNA sequence‐recognition and mechanistic properties.
Construction of Multi‐Enzyme Integrated Catalysts for Deracemization of Cyclic Chiral Amines
Authors: Zhou Liya , Li Chunliu , Dong Lele , Liu Yunting , He Ying , Liu Guanhua , Bai Jing , Ma Li , Jiang Yanjun 
Published: May 2024

AbstractMulti‐enzyme cascade catalysis has become an important technique for chemical reactions used in manufacturing and scientific study. In this research, we designed a four‐enzyme integrated catalyst and used it to catalyse the deracemization reaction of cyclic chiral amines, where monoamine oxidase (MAO) catalyses the enantioselective oxidation of 1‐methyl‐1,2,3,4‐tetrahydroisoquinoline (MTQ), imine reductase (IRED) catalyses the stereo selective reduction of 1‐methyl‐3,4‐dihydroisoquinoline (MDQ), formate dehydrogenase (FDH) is used for the cyclic regeneration of cofactors, and catalase (CAT) is used for decomposition of oxidative reactions. The four enzymes were immobilized via polydopamine (PDA)‐encapsulated dendritic organosilica nanoparticles (DONs) as carriers, resulting in the amphiphilic core‐shell catalysts. The hydrophilic PDA shell ensures the dispersion of the catalyst in water, and the hydrophobic DON core creates a microenvironment with the spatial confinement effect of the organic substrate and the preconcentration effect to enhance the stability of the enzymes and the catalytic efficiency. The core‐shell structure improves the stability and reusability of the catalyst and rationally arranges the position of different enzymes according to the reaction sequence to improve the cascade catalytic performance and cofactor recovery efficiency.
The PIGTAIL paradigm for a fast and safe transfemoral transcatheter aortic valve replacement
Authors: Gennari Marco , Biroli Matteo , Severgnini Gaia , Olivares Paolo , Ferrari Cristina , Giacari Carlo Maria , Agrifoglio Marco , De Marco Federico , Taramasso Maurizio 
Published: May 2024

AbstractTransfemoral transcatheter aortic valve replacement is the preferred primary access route whenever possible. Despite advancements in expertise and delivery system profiles, complications associated with the primary femoral access still significantly affect procedural morbidity and outcomes. The current standard for accurate main access planning involves proper preprocedural evaluation guided by computed tomography. Several baseline clinical and anatomical features serve as predictors for the risk of vascular injury occurring during or after transcatheter aortic valve replacement. In this paper, we aimed at reviewing the most up‐to‐date knowledge of the topic for a safe transfemoral access approach according to a paradigm we have called “PIGTAIL.”
One‐Pot Catalytic Approaches: Building a New Toolbox for Macromolecular Design
Authors: Yang Fan , Guillaume Lucie , Gauvin Régis M. , Thomas Christophe M. 
Published: May 2024

AbstractOne‐pot processes have emerged as a powerful strategy in (macro)molecular synthesis: integrating a multicatalytic process maximizes efficiency, reduces waste, improves profitability, and provides versatile tools for designing of more sustainable processes without compromising selectivity and activity. This review article provides a critical overview of the application of one‐pot transformations in polymerization, with the goal of synthesizing polymers with tailored structures and functions for a wide range of applications. Recent advances in one‐pot polymerization techniques are highlighted, including examples from controlled polymerization methods such as atom transfer radical polymerization, reversible addition‐fragmentation chain transfer polymerization, and ring‐opening polymerization, among others. Special emphasis is placed on the design and optimization of reaction conditions, catalyst systems, and monomer combinations to achieve precise control over polymer structure and functionality.
CoPS/Co4S3 Heterojunction with Highly Exposed Active Sites and Dual‐site Synergy for Effective Hydrogen Evolution Reactions
Authors: Song Kai , Yang Dian , Zhou Chenjing , Li Qingao , Zhang Lili , Gong Junjie , Zhong Wenwu , Shen Shijie , Chen Shichang 
Published: May 2024

AbstractCobalt phosphosulphide (CoPS) has recently been recognized as a potentially effective electrocatalyst for the hydrogen evolution reaction (HER). However, there have been no research on the design of CoPS‐based heterojunctions to boost their HER performance. Herein, CoPS/Co4S3 heterojunction was prepared by phosphating treatment based on defect‐rich flower‐like Co1‐xS precursors. The high specific surface area of nanopetals, together with the heterojunction structure with inhomogeneous strain, exposes more active sites in the catalyst. The electronic structure of the catalyst is reconfigured as a result of the interfacial interactions, which promote the catalyst‘s ability to adsorb hydrogen and conduct electricity. The synergistic effect of the Co and S dual‐site further enhance the catalytic activity. The catalyst has overpotentials of 61 and 70 mV to attain a current density of 10 mA cm−2 in acidic and alkaline media, respectively, which renders it competitive with previously reported analogous catalysts. This work proposes an effective technique for constructing transition metal phosphosulfide heterojunctions, as well as the development of an efficient HER electrocatalyst.
Photochemical Radical Cascade 6‐endo Cyclization of Dienes with α‐Carbonyl Bromides for the Synthesis of Six‐Membered Benzo‐Fused Lactams
Authors: Sui Jia‐Li , Guo Yang , Xiong Bi‐Quan , Tang Ke‐Wen , Huang Peng‐Fei , Liu Yu , Li Jin‐Heng 
Published: May 2024

Comprehensive SummaryA novel visible‐light‐induced radical cascade 6‐endo cyclization of dienes (N‐(2‐vinylphenyl)acryl amides) is developed utilizing α‐carbonyl bromides as alkyl reagents. This approach affords an efficient way for synthesizing six‐membered benzo‐fused lactam derivatives with chemo‐ and regio‐selectivity and good functional group tolerance. Primary, secondary, and tertiary bromides are well‐compatible with this cascade cyclization reaction.
Photocatalytic [3+2] Cycloaddition of Alkyl/aryl Iodides and Internal Alkynes by Merging Halogen and Hydrogen Atom Transfer
Authors: Gu Zhenyu , Jia Rong , Zeng Tianqing , Zheng Hanliang , Zhu Gangguo 
Published: May 2024

Comprehensive SummaryA visible light photocatalytic [3+2] cycloaddition of alkynes with readily accessible organic iodides as the C3 synthon is developed herein. By merging halogen atom transfer (XAT) and hydrogen atom transfer (HAT), alkyl/aryl iodides serve as a formal diradical precursor and add across C‐C triple bonds to deliver a number of functionalized cyclopentanes in moderate to high yields with exceptional regio‐ and diastereoselectivity. A reductive radical‐polar crossover mechanism, involving the cascade XAT, radical addition, 1,5‐HAT, polar effect‐promoted 5‐endo annulation, single electron transfer (SET) reduction, and protonation, may account for this unprecedented dehalogenative [3+2] cycloaddition. This work not only expands the repertoire of the traditional RATC methodology, but also provides a robust platform for the expedient assembly of cyclopentanes, a valuable structural motif in the realms of medicinal chemistry and material sciences.
Harnessing the Synergy of ZIF‐67 Derived Nanohybrid‐Based Immunosensing for sensitive Detection of Helicobacter pylori
Authors: Saxena Kirti , Bhattacharyya Puja , Deshwal Akanksha , Shrivastava Neeraj , Jain Utkarsh , Malhotra Bansi Dhar , Chakrabarti Sandip , Tripathi Ravi Mani 
Published: May 2024

AbstractDetection of Helicobacter pylori (H. pylori) infection, a significant risk factor for chronic gastritis, peptic ulcers, and gastric adenocarcinoma, poses a formidable challenge due to the lack of sensitive and selective sensing platforms. Herein, we report the synthesis of a zeolitic imidazolate framework‐67 (ZIF‐67) derived Co/Co3O4/C (CoNH) porous nanostructure, optimized for the electrochemical immunosensing of H. pylori‐specific antigen VacA. By calcining ZIF‐67 at elevated temperatures, we obtained CoNH with enhanced electroactivity and conductivity, crucial for signal enhancement. The synthesized CoNH was thoroughly characterized using SEM, TEM, XPS, Raman, and FT‐IR techniques. Further signal amplification was achieved by introducing gold nanoparticles (AuNPs) onto CoNH‐modified screen‐printed carbon electrodes. Systematic investigation at each modification stage led to an optimized immunosensing platform with high sensitivity and selectivity for VacA detection. The developed immunosensor demonstrated the capability to detect low concentrations of VacA (0.1 ng/ml) within a wide linear range (0.1–50 ng/ml) with long‐term stability. This highly sensitive and selective biosensor holds promise for early‐stage diagnosis of H. pylori infection and gastric cancer.
An investigation of the Excitation Wavelength‐Dependent Dynamic Changes in the Mechanism of Detection of Picric Acid using Pyrene‐Based Donor‐Acceptor Systems
Authors: Sreelaya V. , Rohman Shahnaz S. , Parameswaran Pattiyil , Chakkumkumarath Lakshmi 
Published: May 2024

AbstractPicric acid (PA) is an important industrial feedstock and hence the release of industrial effluents without proper remediation results in its buildup in soil and water bodies. The adverse effects of PA accumulation in living beings necessitate the development of efficient methods for its detection and quantification. Herein, we describe pyrene‐based fluorescent sensors for PA, where pyrene is appended with electron‐withdrawing groups, malononitrile, and 2‐(3‐cyano‐4,5,5‐trimethylfuran‐2(5H)‐ylidene) malononitrile (DCDHF). These molecules displayed the typical emission of pyrene monomers, as well as a broad red‐shifted emission resulting from an intramolecular charge transfer (ICT) in the excited state. Both the emissions displayed a turn‐off response to PA with high selectivity and sensitivity and the lowest limit of detection was estimated as 27 nM. To prove the feasibility of on‐site detection, test paper strips were prepared, which could detect PA up to 4.58 picograms. Using a combination of experimental and theoretical studies the mechanism of the detection was identified as primary/secondary inner filter effect, oxidative photoinduced electron transfer, or a combination of both depending on the excitation wavelength. Interestingly, the contribution of each of these mechanisms to the total quenching process varied with a change in the excitation wavelength.
Atomic Insight into the Enzymatic Selectivity of Acetyltransferase for Endogenous Polyamines
Authors: Guo Baolin , Xue Qian , Zhang Zhiyang , Zhai Jihang , Wang Chaojie , Zhao Yuan , Zhang Jie 
Published: May 2024

AbstractThe N1−Spermidine/spermine acetyltransferase (SSAT) serves as the rate‐limiting enzyme in the polyamine metabolism pathway, specifically catalyzing the acetylation of spermidine, spermine, and other specific polyamines. The source of its enzymatic selectivity remains elusive. Here, we used quantum mechanics and molecular mechanics simulations combined with various technologies to explore the enzymatic mechanism of SSAT for endogenous polyamines from an atomic perspective. The static binding and chemical transformation were considered. The binding affinity was identified to be dependent on protonated state of polyamine. The order of the binding affinity for Spm, Spd, and Put is consistent with the experimental results, which is also verified by the dynamic separation of polyamine and SSAT. Hydrogen bond interactions and salt bridges contribute most, and the common hot residues were identified. In addition, the transfer of acetyl and proton between polyamine and AcCoA was discovered to follow a concert mechanism, and thermodynamic properties are responsible for the catalytic efficiency of SSAT. This work may be helpful for development of polyamine derivatives based on catalysis to regulate polyamine metabolism.
Buckybowl Molecular Tweezers for Recognition of Fullerenes
Authors: Oshchepkov Alexander S. 
Published: May 2024

AbstractBuckybowl tweezers are a relatively young research area closely associated with the development of non‐planar polycyclic aromatic systems and supramolecular chemistry. Since the appearance of the first prototypes in the early 2000s, the tweezers have undergone evolutionary changes. Nowadays they are able to effectively interact with fullerenes and the results opened up prospects for development in the field of sensing, nonlinear optics, and molecular switchers. In the present study, examples of corannulene‐based and other buckybowl tweezers for the recognition of C60 and C70 fullerenes were summarized and analyzed. The main structural components of the tweezers were also reviewed in detail and their role in the formation of complexes with fullerenes was evaluated. The revealed structural patterns should trigger the development of novel recognition systems and materials with a wide range of applications.
Design, Synthesis, and Photochemical Properties of Gene‐directed Caged RyR Probes for Photopharmacological Studies
Authors: Yokoyama Aika , Aoki Hanami , Funayama Mizuki , Shinozaki Ryo , Yoshida Hiroto , Suzuki Akinobu Z. , Furuta Toshiaki 
Published: May 2024

AbstractRyanodine receptor (RyR) is a crucial intracellular Ca2+ channel involved in various physiological processes associated with several diseases. This paper presents the synthesis and evaluation of novel photoactivatable caged compounds for the RyR. We used (6‐bromo‐7‐hydroxycoumarn‐4‐yl)methyl (Bhc) as the photolabile protecting group to develop caged versions of 4‐CmC, a broad‐spectrum RyR agonist, and FLA365, an antagonist. The synthesized compounds, Bhcmoc‐4‐CmC and Bhcmoc‐FLA365, exhibited photoreactivity that enabled spatiotemporal control over the RyR activity. Bhcmoc‐4‐CmC presents a quantum yield of 25 % and a photolysis efficiency of 1,075 M−1 cm−1 under 405 nm light, triggering Ca2+ release from the endoplasmic reticulum. Conversely, Bhcmoc‐FLA365 presents a reduced quantum yield of 0.61 %, which can be attributed to the quenching effects of its tertiary amine structure. We also applied gene‐directed caging, synthesizing β‐galactosidase (β‐Gal) activatable Gal‐Bhcmoc‐4‐CmC and Gal‐Bhcmoc‐FLA365, and porcine liver esterase (PLE)‐activatable CM‐Bhcmoc‐FLA365, to target these probes to the specific cell types. These caged compounds contribute significantly to photopharmacology, providing tools for the precise analysis and manipulation of the RyR functions. Future research objectives involve further optimization and analysis of the photochemical mechanisms of these caged compounds to enhance their applications in biological and medical research.
Surface Plasmon Resonance‐Mediated Photocatalytic H2 Generation
Authors: Zhang Xiaohan , Wang Cong , Zhang Menglong , Luo Dongxiang , Ye Siyu , Weng Bo 
Published: May 2024

AbstractThe limited yield of H2 production has posed a significant challenge in contemporary research. To address this issue, researchers have turned to the application of surface plasmon resonance (SPR) materials in photocatalytic H2 generation. SPR, arising from collective electron oscillations, enhances light absorption and facilitates efficient separation and transfer of electron‐hole pairs in semiconductor systems, thereby boosting photocatalytic H2 production efficiency. However, existing reviews predominantly focus on SPR noble metals, neglecting non‐noble metals and SPR semiconductors. In this review, we begin by elucidating five different SPR mechanisms, covering hot electron injection, electric field enhancement, light scattering, plasmon‐induced resonant energy transfer, and photo‐thermionic effect, by which SPR enhances photocatalytic activity. Subsequently, a comprehensive overview follows, detailing the application of SPR materials‐metals, non‐noble metals, and SPR semiconductors‐in photocatalytic H2 production. Additionally, a personal perspective is offered on developing highly efficient SPR‐based photocatalysis systems for solar‐to‐H2 conversion in the future. This review aims to guide the development of next‐gen SPR‐based materials for advancing solar‐to‐fuel conversion.
Bimetallic MOFs‐Derived NiFe2O4/Fe2O3 Enabled Dendrite‐free Lithium Metal Anodes with Ultra‐High Area Capacity Based on An Intermittent Lithium Deposition Model
Authors: Wang Mengting , Wei Tao , Lu Jiahao , Guo Xingtong , Sun Cheng , Zhou Yanyan , Su Chao , Chen Shanliang , Wang Qian , Yang Ruizhi 
Published: May 2024

AbstractIn practical operating conditions, the lithium deposition behavior is often influenced by multiple coupled factors and there is also a lack of comprehensive and long‐term validation for dendrite suppression strategies. Our group previously proposed an intermittent lithiophilic model for high‐performance three‐dimensional (3D) composite lithium metal anode (LMA), however, the electrodeposition behavior was not discussed. To verify this model, this paper presents a modified 3D carbon cloth (CC) backbone by incorporating NiFe2O4/Fe2O3 (NFFO) nanoparticles derived from bimetallic NiFe‐MOFs. Enhanced Li adsorption capacity and lithiophilic modulation were achieved by bimetallic MOFs‐derivatives which prompted faster and more homogeneous Li deposition. The intermittent model was further verified in conjunction with the density functional theory (DFT) calculations and electrodeposition behaviors. As a result, the obtained Li‐CC@NFFO||Li‐CC@NFFO symmetric batteries exhibit prolonged lifespan and low hysteresis voltage even under ultra‐high current and capacity conditions (5 mA cm−2, 10 mAh cm−2), what's more, the full battery coupled with a high mass loading (9 mg cm−2) of LiFePO4 cathode can be cycled at a high rate of 5 C, the capacity retention is up to 95.2 % before 700 cycles. This work is of great significance to understand the evolution of lithium dendrites on the 3D intermittent lithiophilic frameworks.
A 2.72 μs row conversion time 11‐bit column‐parallel single‐slope analog to digital converter with differential‐clocks‐assisted time to digital converter interpolation for complementary metal oxide semiconductors image sensor
Authors: Duan Hao , Nie Kaiming , Xu Jiangtao 
Published: May 2024

AbstractThis paper presents an innovative readout scheme that utilizes a pair of differential‐clocks‐assisted time‐to‐digital converter (DCA‐TDC) in CMOS image sensors (CISs). The DCA‐TDC utilizes only half the number of ordinary TDC delay chain units by employing a binary‐weighted search algorithm to determine the most significant bit (MSB) for fine quantization of a single‐slope analog‐to‐digital converter (SS ADC). Additionally, the layout area and dynamic power introduced by the improved DCA‐TDC delay chain are halved compared to an ordinary TDC delay chain. The proposed SS ADC is designed and simulated using the 0.11
m standard CMOS proces, achieving an 11‐bit ADC with a column‐level power consumption of 65.4
W, and a row conversion time of 2.72
s, within a design environment featuring an analog voltage of 3.3 V, a digital voltage of 1.5 V, a clock frequency of 62.5 MHz, and a temporal resolution of 500 ps. Furthermore, this design achieves an effective number of bits (ENOB) of 10.71 and a figure of merit (FoM) of 110.5 fJ/step. By interpolating a DCA‐TDC, the quantization speed is enhanced compared to traditional SS ADCs, presenting an effective solution for high‐frame‐rate CIS implementations.
High voltage gain minimum‐phase isolated DC‐DC converter with improved transformer utilization
Authors: Obulapathi Balapanuru , Lokhande Makarand M. , Aware M. V. 
Published: May 2024

AbstractThe standard structure of an isolated SEPIC (iSEPIC) does not have a minimum‐phase nature, which signifies no additional support for the output capacitor during ON‐time conditions. Consequently, it has high voltage stress, right half plane (RHP) zeros presence, DC component in the transformer core, and less transformer utilization. This paper presents a modification in a iSEPIC converter having higher voltage gain over a conventional iSEPIC converter. This work analyzes a modified iSEPIC structure by providing additional support to the output capacitor during ON‐time conditions. As a result, the nonminimum‐phase nature will be transformed into the minimum‐phase nature. Consequently, all the mentioned demerits of the standard iSEPIC structure are eliminated The derived discrete‐time modeling analyzes the RHP zeros dependence on the load variation. This modification also leads to improvement in dynamic performance to accommodate the load variation. Finally, a 60 W modified iSEPIC prototype is developed to validate the proposed analysis.