INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Zuyue Li,Jiaojiao Chen,Mahmoud Abou-Elsoud,Long Sheng,Dong Uk Ahn,Dewei Shu,Meiyu Liu,Xi Huang
Storage of shell eggs converts natural ovalbumin (N-OVA) into its more thermostable forms (S-OVA). This conversion may be associated with deterioration in the foaming properties of the stored shell egg. Thus, the foaming behavior of N-OVA and S-OVA, especially their performance at different pH conditions, was conducted. Compared with N-OVA, S-OVA improved foaming ability by 29.04 % at pH 3.0 and exhibited rough foam. Regarding foaming stability, the conversion of N-OVA to S-OVA had a pronounced reduction effect, with foaming stability significantly decreasing by 28.48 %–100.00 % in pH 3.0–9.0. The spectroscopic analysis revealed that the alteration in the foaming properties of OVA was fundamentally attributed to its conformational change. Thermostable conformational transition provided S-OVA with smaller particle sizes, more flexible conformations, higher surface charge, and higher surface hydrophobicity. S-OVA at pH 3.0 showed a higher surface activity, indicating superior foaming ability. Moreover, N-OVA and S-OVA formed stiff and solid-like interfaces. Notably, N-OVA exhibited higher dilatational and elastic modulus, indicating a more compact and stable adsorption layer at air-water interface. Overall, thermostable conformational transition improved the interfacial activity of OVA and enhanced its foaming ability; however, overactive proteins were detrimental to the stabilization of its interfacial films.
研究领域:
食品科学
·
蛋白质化学
✓ 已验证
DOI
PubMed
高影响因子
Polymers
·
2018
·Vol. 10
·期 9
·1007
·
IF 2.935
Linlin Qin,Linling Li,Ye Sha,Ziyu Wang,Dongshan Zhou,Wei Chen,Gi Xue
The critical overlap concentrationC*is an important concept in polymer solutions and is defined as the boundary between dilute and semidilute regimes. In this study, the chain conformational changes of polystyrene (PS) with both high (Mn= 200,000 Da) and low (Mn= 13,000 Da) molecular weights in cis-decalin were compared by intrachain fluorescence resonance energy transfer (FRET). The random labeling of donor and acceptor chromophores strategy was employed for long PS chains, whereas chain-end labeling was used for short PS chains. By monitoring the spectroscopic intensity ratio between acceptor and donor, the concentration dependence on chain conformation from dilute to semidilute solutions was determined. Both long and short chains exhibit a conformational transition concentration, above which the polymer chains begin to collapse with concentration significantly. Interestingly, for randomly labeled polymer long chains, such concentration is consistent withC*determined from the viscosity result, below which only slight conformational change of polymer chain takes place. However, for the chain-end labeled short chain, the conformational transition concentration takes place earlier thanC*, below which no significant polymer conformation change is observed.Keywords:polymer solution;conformational transition;critical overlap concentration;fluorescence;viscosity
研究领域:
高分子化学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2023
·
IF 5
Yana Wang,Jiapeng Zhang,Shuanglu Chen,Xiaohua Zhang,Yitan Li,Zhaohui Yang
Spider silks, mainly constructed of spidroin, have received extensive attention for their excellent mechanical properties, slow bio-degradability, and high biocompatibility. However, due to uncontrollable protein-folding processes, the structural transition of spidroin, especially when composited with other functional materials under confinement, is insufficiently understood. Herein, we report a pressure-induced conformational transition process of the spidroin which is confined within carbon nanotube (CNT) sponge matrixes. The structural transition of spidroin from α-helix to β-sheet can be induced by a very small hydrostatic pressure (several megapascals) and recover easily through a subsequent solvent vapor annealing process in an ambient atmosphere. Therefore, the spidroin/CNT sponge exhibits reversible vapor-/pressure-sensitive “shape-memory” behavior with the recovery efficiency close to 100%. Our observation reveals a crucial mechanism for the conformational transition of spidroin under confinement, which paves the way toward the fabrication of spider silk-based products with superior performances.
研究领域:
材料科学
·
生物材料
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
PROTEIN JOURNAL
·
2016
·Vol. 35
·期 2
·154-162
·
IF 1.029
Tian Mei-ling,Fang Ting,Du Mu-ying,Zhang Fu-sheng
To explore an efficient, safe, and speedy application of pulsed electric field (PEF) technology for enzymatic modification, effects of PEF treatment on the enzymatic activity, property and kinetic parameters of α-amylase were investigated. Conformational transitions were also studied with the aid of circular dichroism (CD) and fluorescence spectra. The maximum enzymatic activity of α-amylase was obtained under 15 kV/cm electric field intensity and 100 mL/min flow velocity PEF treatment, in which the enzymatic activity increased by 22.13 ± 1.14 % compared with control. The activation effect could last for 18 h at 4 °C. PEF treatment could widen the range of optimum temperature for α-amylase, however, it barely exerted any effect on the optimum pH. On the other hand, α-amylase treated by PEF showed an increase of V
max , t 1/2 and Δ G , whereas a decrease of K
m and k were observed. Furthermore, it can be observed from fluorescence and CD spectra that PEF treatment had increased the number of amino acid residues, especially that of tryptophan, on α-amylase surface with enhanced α-helices by 34.76 % and decreased random coil by 12.04 % on α-amylase when compared with that of untreated. These changes in structure had positive effect on enhancing α-amylase activity and property.
研究领域:
食品科学
·
生物技术
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Rourou Zhang,An Ding,Xuejun Cai,Peter Desmond,Xu He,Guibai Li,Heng Liang,Chuyang Y. Tang
The fluctuation of pathogen removal in ultrafiltration (UF) systems and its dependence on irreversible fouling necessitates frequent chemical cleaning/disinfection, raising concerns about leakage of conditioned pathogens. An additional barrier utilizing carbon materials with notable adsorption and antimicrobial properties offers a promising and practical solution. This study achieved complete retention of nano-sized viruses (∼6 log reduction value (LRV)) and micron-sized bacteria (∼7 LRV) by introducing ε-polylysine (EPL)-modified biochar (BC) into UF feeds. During the UF process, biochar with superior adsorption capacities and conformational flexibility, significantly enhanced the entrapments of natural organic matter (NOM), viruses, and bacteria. Specially, EPL exhibited conformational transitions that adapted to different NOM (macromolecule proteins and linear polysaccharides), greatly facilitating the formation of reversible biochar-NOM cake layers and the transfer of pathogens from the irreversible fouling layer to the biochar surface and reversible fouling layer. The random coil structures of EPL promoted electrostatic attraction for virus particles, while bend or sheet-like structures created barriers for both bacteria and viruses through a refined NOM-biochar network. The trapping of viruses was attributed to the combined effects of electrostatic attraction, bonding forces, and the complex cake layers. And size exclusion by the biochar-NOM complex fouling layer played a prominent role in the retention of bacteria. This breakthrough in addressing the trade-off between irreversible fouling and pathogen removal inspires promising applications of EPL-modified biochar for UF systems to consolidate barriers for water and process biosafety. Future efforts should focus on EPL′s conformational response to protein-like NOM with significant steric hindrance, which pose challenges for fouling alleviation and bacteria capture.
研究领域:
环境工程
·
水处理
·
膜技术
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
BIOPHYSICAL CHEMISTRY
·
2024
·
IF 3.3
Xiangyuan Zhao,Chunyan Yang,Wei Liu,Ke Lu,Hao Yin
A novel inhibitor, carboxyphenylboronic acid-modified chitosan oligosaccharide (COS-CPBA), was developed by coupling carboxyphenylboronic acid (CPBA) with chitosan oligosaccharide (COS) to inhibit insulin fibrillation. Extensive biophysical assays indicated that COS-CPBA could decelerate insulin aggregation, hinder the conformational transition from α-helix to β-sheet structure, change the morphology of insulin aggregates and alter fibrillation pathway. A mechanism for the inhibition of insulin fibrillation by COS-CPBA was proposed. It considers that insulin molecules bind to COS-CPBA via hydrophobic interactions, while the positively charged groups in COS-CPBA exert electrostatic repulsion on the bound insulin molecules. These two opposite forces cause the insulin molecules to display extended conformations and hinder the conformational transition of insulin from α-helix to β-sheet structure necessary for fibrillation, thus decelerating aggregation and altering the fibrillation pathway of insulin. The studies provide novel ideas for the development of more effective inhibitors of amyloid fibrillation.
研究领域:
药学
·
生物物理学
·
化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2025
·
IF 16
Run Pan,Hao Li,Xiaoyao Wang,Heng Zhang,Luis M. Liz-Marzán,Chao Zhou,Weihai Ni
Characterization of the dynamics of individual reconfigurable chiral plasmonic nanostructures (metamolecules) in various local environments provides critical information toward understanding the principles and mechanisms involved in designing and constructing metamolecules. However, time-resolved statistical analysis of transition trajectories is required at the single-metamolecule level. Therefore, we developed a high-throughput time-resolved circular differential scattering (TRCDS) method for characterizing dynamic processes in single metamolecules immobilized on a substrate. This method allowed us to perform time-resolved trajectory measurements during the conformational transition of individual reconfigurable plasmonic metamolecules between two enantiomeric states, driven by the hybridization of single DNA strands in situ in an aqueous environment. High-throughput optical characterization supported a statistical analysis based on simultaneous measurements of hundreds of reconfigurable metamolecules with slight differences in their individual structures and local environments, within the field-of-view of the microscope. Statistical analysis revealed a transition path time τTP = 123.7 ms for the conformational transition. Engineering of the dynamic reconfiguration of metamolecules was demonstrated by varying the dynamic DNA strands from 8 to 11 and 14 nucleotides, resulting in an increased stability of the enantiomeric states. Our study enables the dynamic manipulation of reconfigurable plasmonic nanostructures and the rational construction of smart systems.
研究领域:
纳米光子学
·
等离激元学
·
超材料
·
单分子分析
·
生物光子学
·
DNA纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2018
·
IF 6.042
Lihua Lu,Huijuan Su,Qingyun Liu,Feng Li
To improve the G-quadruplex specificity of Ir(III) complexes, a novel dinuclear Ir(III) complex (Din Ir(III)–1) was designed and synthesized through connecting two mononuclear Ir(III) complexes via a diphenyl bridge. Din Ir(III)–1 presents 3.4–4.1-fold enhancements for G-quadruplex relative to ssDNA and 4.3–5.3-fold enhancements relative to dsDNA in luminescence intensity, respectively, demonstrating an excellent G-quadruplex selectivity. Ascribed to its superior specificity to G-quadruplex, Din Ir(III)–1 was employed to construct a highly sensitive luminescent pesticides’ detection platform. The detection is based on acetylcholinesterase (AChE)-catalyzed hydrolysis product-induced DNA conformational transformation and subsequent terminal deoxynucleotidyl transferase (TdT) directed G-quadruplex formation. The assay exhibited a linear response between the emission intensity of Din Ir(III)–1 and the pesticide concentration in the range of 0.5–25 μg/L (R2 = 0.994), and the limit of detection for the pesticide was as low as 0.37 μg/L when using aldicarb as the model pesticide. Moreover, this strategy demonstrates good applicability for the pesticide detection in real samples. It is also versatile for the detection of other organophosphate or carbamate pesticides, which have the inhibition ability toward AChE. Therefore, the proposed approach is scalable for practical application in food safety and environmental monitoring fields and will provide promising solutions for the assay of pesticide residues.
研究领域:
分析化学
·
材料科学
·
环境科学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMACROMOLECULES
·
2023
·
IF 6.2
Songlin Xing,Qiqi Wang,Yang He,Li Chen
Polymer brushes with different topological architectures exhibit unparalleled interfacial and physicochemical properties and are being widely utilized in antifouling applications. However, there is an absence of a thorough understanding of the antifouling process of dynamic flow mediated by the topological structure of polymer brushes. Here, it is highlighted how the interface parameters related to biofouling in flowing carrier fluid are tuned by topologically different architectures. The mechanism by which three brushes with various topological structures (cyclic, looped, and linear brushes) encounter biological media was revealed by relating protein adhesion with nanomechanics and protein conformational transitions on poly(2-ethyl-2-oxazoline) (PEtOx) brushes. In contrast to the classically linear analogue, the cyclic PEtOx brushes confered an enhanced steric barrier and excellent lubrication at the critical density region. The impenetrable and smoother layer prevented the approach and shortened the residence time for protein on the surface, providing optimal antifouling properties at low shear rates. The looped brushes also significantly inhibited protein adhesion under prolonged high shear rates due to their unshakable conformational characteristics. These findings detailed a new evaluation framework behind polymer brushes of topology-driven biofouling repulsion under flow conditions and pointed the way toward a promising approach for the effectiveness of biomaterial design.
研究领域:
聚合物科学
·
材料科学
·
生物医学工程
·
表面化学
·
生物物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2025
·
IF 16
Jue-Ying Gong,Yao Li,Po Wang,Xu Peng,Rui Xie,Wei Wang,Zhuang Liu,Da-Wei Pan,Xiao-Jie Ju,Liang-Yin Chu
Intracellular bacteria can evade the attack of the immune system and the bactericidal effects of most antibiotics due to the protective effect of the host cells. Herein, inspired by the stimuli-responsive behaviors of biological ion channels, a kind of synergistic cascade potassium ion (K+)-responsive nanoparticles gated with K+-responsive polymers is ingeniously designed to target intracellular bacteria and then control drug release. Due to the cooperative interaction of host–guest complexation and conformational transition of K+-responsive polymers, the grafted gates based on these polymers could recognize high K+ concentration to reverse the negatively charged nanoparticles into positively charged ones for targeting bacteria and subsequently inducing a switch from the hydrophobic shrinking “off” state to the hydrophilic stretching “on” state for drug release. The K+-responsive nanoparticles can effectively load antibiotics and be endocytosed into the infected cells, and K+-responsive gates can be actuated by a high intracellular K+ concentration. With the efficient synergistic cascade strategy, these K+-responsive nanocarriers can deliver antibiotics to the subcellular region where intracellular bacteria reside and show superior elimination efficiencies in vitro and in vivo than the free drug in delivering vancomycin. The K+-responsive nanocarriers are expected to improve the bioavailability of drugs and enhance their antibacterial efficacy.
研究领域:
纳米技术
·
药学
·
细菌学
·
药物递送系统
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）