JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
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2024
·Vol. 129
·期 4
·e2023JE008031
·
IF 3.9
Xinyi Xiang,Peixin Du,Binlong Ye,Hongling Bu,Dong Liu,Jiacheng Liu,Jian Hua,Xiaolong Guo
Ferrihydrite, a nanocrystalline iron (oxyhydr)oxide mineral, is widely distributed in soils and sediments on Earth and is probably an important component and/or precursor of widespread nanophase iron minerals on Mars. Terrestrial ferrihydrite often co-occurs with amorphous silica and/or contains a certain amount of Si in its structure. However, it remains ambiguous how environmental Si concentration affects the formation-evolution and structure-spectral features of ferrihydrite in the Fe(III)-Si systems. To this end, hydrolysis experiments were carried out for Fe-Si systems at an unprecedentedly wide range of initial Si/(Fe + Si) molar ratios (0–0.80), followed by characterizing the products detailly. X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, Mössbauer spectroscopy, and transmission electron microscopy results showed that at Si/(Fe + Si) molar ratios ≤0.30, the main phase of the products was ferrihydrite, of which the unit cells enlarged, the crystallinity decreased, and the existing state of Fe changed with increased Si contents; at Si/(Fe + Si) molar ratios ≥0.40, ferrihydrite was no longer formed and a novel amorphous Fe-O-Si phase was instead obtained, with the excess Si forming amorphous silica. The visible and near-infrared spectroscopy, the most powerful tool to detect hydrous minerals on the surface of Mars at global or regional scales, showed weakness in identifying ferrihydrite-like materials obtained in the Fe-Si systems. Raman spectroscopy can identify ferrihydrite and Si-containing ferrihydrite but cannot differentiate between them. Mössbauer spectroscopy showed great potential in both identifying and differentiating between ferrihydrite and Si-containing ferrihydrite, and thus can be used to characterize the poorly ordered iron (oxyhydr)oxides on Mars. Key Points Hydrolysis experiments of Fe(III)-Si systems were performed at an unprecedentedly wide range of initial Si/(Fe + Si) molar ratios (0∼0.80) The environmental Si concentration controls the formation and evolution of ferrihydrite in the Fe(III)-Si systems Mössbauer spectroscopy shows great potential in identifying and differentiating between ferrihydrite-like materials Plain Language Summary On the surface of ancient Mars where liquid water was available, Fe-Si hydrolysis systems were likely common as a result of the high abundances of Fe and Si in the crust of Mars. By performing hydrolysis experiments of Fe-Si systems at an unprecedented wide range of Si/(Fe + Si) molar ratios, we found that the hydrolysis products of Fe-Si systems varied among combinations of ferrihydrite, Si-containing ferrihydrite, an unknown Fe-O-Si phase, and amorphous silica. We also found that the visible and near-infrared reflectance spectroscopy, the most powerful tool to remotely detect hydrous minerals on the surface of Mars at global and regional scales, showed weakness in identifying ferrihydrite, Si-containing ferrihydrite, and the novel Fe-O-Si phase; Raman can be used to identify ferrihydrite-like materials but cannot be used to differentiate between ferrihydrite and Si-containing ferrihydrite; mid-infrared spectroscopy can differentiate ferrihydrite from Si-containing ferrihydrite and the novel Fe-O-Si phase; Mössbauer spectroscopy (recorded at varied temperatures) provided clues to identifying and further differentiating between ferrihydrite-like materials and thus holds great potential for detecting Fe/Si-rich phases on the surface of Mars.
研究领域:
地质学
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行星科学
·
矿物学
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DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2019
·
IF 2.12
Xiaopei Wang,Yuanyuan Yue,Yanyan Zhang,Zhiyue Wang,Jianming Liu,Qinghu Tang
The use of the pesticide imidacloprid can be hazardous to human health. In this work, the impacts of imidacloprid on the secondary structure of pepsin were investigated through spectroscopic techniques and simulation studies. One binding site for pepsin with strong affinity was evident from changes in the fluorescence emission spectra of pepsin in the presence of imidacloprid. Calculated thermodynamic parameters based on the van't Hoff relationship indicate the predominance of hydrophobic and hydrogen bonding interactions contributing to the imidacloprid-pepsin complex. Structural changes in pepsin were also evident from changes in the UV, FTIR , CD , three-dimensional fluorescence (3D), and synchronous fluorescence spectroscopy (SFS) of pepsin upon titration with imidacloprid. Furthermore, density functional theory (DFT) calculations and molecular docking studies revealed predominant binding of imidacloprid in the hydrophobic pocket of pepsin.
研究领域:
生物化学
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毒理学
·
计算生物学
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产品关联
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 3
·655
·
IF 4.2
Si-Hua Fan,Wen-Qiang Wang,Yu-Wen Zhou,Xue-Jun Gao,Qiang Zhang,Ming-Hui Zhang
The interaction between human serum albumin (HSA) and hispidin, a polyketide abundantly present in both edible and therapeutic mushrooms, was explored through multispectral methods, hydrophobic probe assays, location competition trials, and molecular docking simulations. The results of fluorescence quenching analysis showed that hispidin quenched the fluorescence of HSA by binding to it via a static mechanism. The binding of hispidin and HSA was validated further by synchronous fluorescence, three-dimensional fluorescence, and UV/vis spectroscopy analysis. The apparent binding constant (Ka) at different temperatures, the binding site number (n), the quenching constants (Ksv), the dimolecular quenching rate constants (Kq), and the thermodynamic parameters (∆G, ∆H, and ∆S) were calculated. Among these parameters, ∆H and ∆S were determined to be 98.75 kJ/mol and 426.29 J/(mol·K), respectively, both exhibiting positive values. This observation suggested a predominant contribution of hydrophobic forces in the interaction between hispidin and HSA. By employing detergents (SDS and urea) and hydrophobic probes (ANS), it became feasible to quantify alterations in Ka and surface hydrophobicity, respectively. These measurements confirmed the pivotal role of hydrophobic forces in steering the interaction between hispidin and HSA. Site competition experiments showed that there was an interaction between hispidin and HSA molecules at site I, which situates the IIA domains of HSA, which was further confirmed by the molecular docking simulation.Keywords:human serum albumin;hispidin;fluorescence survey;molecular docking;spectrophotometry
研究领域:
生物化学
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药理学
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分子生物学
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光谱学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2014
·
IF 3.259
Yajie Wang,Guowen Zhang,Jiakai Yan,Deming Gong
Tyrosinase is a key enzyme in the production of melanin in the human body, excessive accumulation of melanin can lead to skin disorders. Morin is an important bioactive flavonoid compound widely distributed in plants and foods of plant origin. In this study, the inhibitory kinetics of morin on tyrosinase and their binding mechanism were determined using spectroscopic and molecular docking techniques. The results indicate that morin reversibly inhibited tyrosinase in a competitive manner through a multi-phase kinetic process. Morin was found to bind to tyrosinase at a single binding site mainly by hydrogen bonds and van der Waals forces. Analysis of circular dichroism spectra revealed that the binding of morin to tyrosinase induced rearrangement and conformational changes of the enzyme. Moreover, molecular docking results suggested that morin competitively bound to the active site of tyrosinase with the substrate levodopa.
研究领域:
生物化学
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药理学
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DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2024
·
IF 7
Yan Hu,Wei Chen,Mostafa Gouda,Huan Yao,Xinxin Zuo,Huahao Yu,Yuying Zhang,Lejia Ding,Fengle Zhu,Yuefei Wang,Xiaoli Li,Jihong Zhou,Yong He
Fuzhuan brick tea (FBT) fungal fermentation is a key factor in achieving its unique dark color, aroma, and taste. Therefore, it is essential to develop a rapid and reliable method that could assess its quality during FBT fermentation process. This study focused on using electronic nose (e-nose) and spectroscopy combination with sensory evaluations and physicochemical measurements for building machine learning (ML) models of FBT. The results showed that the fused data achieved 100 % accuracy in classifying the FBT fermentation process. The SPA-MLR method was the best prediction model for FBT quality (R 2 = 0.95, RMSEP = 0.07, RPD = 4.23), and the fermentation process was visualized. Where, it was effectively detecting the degree of fermentation relationship with the quality characteristics. In conclusion, the current study’s novelty comes from the established real-time method that could sensitively detect the unique post-fermentation quality components based on the integration of spectral, and e-nose and ML approaches.
研究领域:
食品科学
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化学计量学
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微生物学
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产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2017
·
IF 2.536
Jie-Hua Shi,Kai-Li Zhou,Yan-Yue Lou,Dong-Qi Pan
Molecular interaction of darunavir (DRV), a HIV protease inhibitor with calf thymus deoxyribonucleic acid (ct-DNA) was studied in physiological buffer (pH 7.4) by multi-spectroscopic approaches hand in hand with viscosity measurements and molecular docking technique. The UV absorption and fluorescence results together revealed the formation of a DRV–ct-DNA complex having binding affinities of the order of 10 3 M − 1 , which was more in keeping with the groove binding. The results that DRV bound to ct-DNA via groove binding mode was further evidenced by KI quenching studies, viscosity measurements, competitive binding investigations with EB and Rhodamine B and CD spectral analysis. The effect of ionic strength indicated the negligible involvement of electrostatic interaction between DRV and ct-DNA. The thermodynamic parameters regarding the binding interaction of DRV with ct-DNA in terms of enthalpy change (Δ H 0 ) and entropy change (Δ S 0 ) were − 63.19 kJ mol − 1 and − 141.92 J mol − 1 K − 1 , indicating that hydrogen bonds and van der Waals forces played a predominant role in the binding process. Furthermore, molecular simulation studies suggested that DRV molecule was prone to bind in the A-T rich region of the minor groove of DNA.
研究领域:
生物化学
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药物化学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2023
·Vol. 25
·期 10
·7239-7250
·
IF 3.3
Haoyang Li,Simin Cao,Sanjun Zhang,Jinquan Chen,Jianhua Xu,Jay R. Knutson
Ultrafast Förster Resonance Energy Transfer (FRET) between tyrosine (Tyr) and tryptophan (Trp) residues in the protein monellin has been investigated using picosecond and femtosecond time-resolved fluorescence spectroscopy. Decay associated spectra (DAS) and time-resolved emission spectra (TRES) taken with the different excitation wavelengths of 275, 290 and 295 nm were constructed via global analysis. At two of those three excitation loci (275 and 290 nm), earmarks of energy transfer from Tyr to Trp in monellin are seen, and particularly when the excitation is 275 nm, the energy transfer between Tyr and Trp clearly changes the signature emission DAS shape to that indicating excited state reaction (especially on the red side of fluorescence emission, near 380 nm). Those FRET signatures may overlap with the conventional signatory DAS in heterogeneous systems. When overlap and addition occur between FRET type DAS and “full positive” QSSQ (quasi-static self-quenching), mixed DAS shapes will emerge that still show “positive blue side and negative red sides”, just with zero crossing shifted. In addition, excitation decay associated spectra (EDAS) taken with the different emission wavelengths of 330, 350 and 370 nm were constructed. In the study of protein dynamics, ultrafast FRET between Tyr and Trp could provide a basis for an intrinsic (non-perturbing) “spectroscopic ruler”, potentially a powerful tool to detect even slight changes in protein structures.
研究领域:
生物物理学
·
蛋白质科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2023
·
IF 3.8
Wulan Zeng,Xia Wang,Xiangjun Kong,Youwang Li,Yunju Zhang
A new spirocompound containing thiourea group 1-((2,4-dioxo-1,5-dioxaspiro[5.5]undecan-3-ylidene)methyl)-3-phenylthiourea (DMP) was designed and obtained. The compound (DMP) was confirmed using the single X-ray diffraction, 1 H NMR and 13 C NMR, IR, Raman, MS and UV–Vis. The DFT calculations of molecular structure, infrared and Raman spectroscopy and electronic transition were performed using the two different levels of B3LYP/cc-pVDZ/ and B3LYP/6–311G(d, p). The theoretical results match with the experimental ones. The gap energy of HOMO and LUMO of DMP was 3.88 eV. The DMP is thermally stable up to 200 °C according to the data obtained from TG analysis. Finally, the Mulliken population analysis, Hirshfeld surfaces analysis, MEP, NLO and NBO of DMP were discussed.
研究领域:
化学
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材料科学
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物理化学
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产品关联
DOI
高影响因子
SPECTROSCOPY LETTERS
·
2020
·
IF 0.88
Yanbin Su,Xuwei Sun,Ruixue Wu,Xing Zhang,Yunzhou Tu
The purpose of this study was to explore the molecular spectroscopic behaviors of the beta-arbutin on the toxic aldehyde of trans-crotonaldehyde in anti-skin cancer. Results revealed that both hydroxymethyl and phenolic hydroxyl of beta-arbutin led to the shift of the maximum ultraviolet peak of trans-crotonaldehyde from a very significant absorption peak at 300 nm to a very weak absorption peak at 310 nm and the significant shift of the aldehyde Raman band at 1689/cm of the toxic trans-crotonaldehyde in mitochondria and aldehyde dehydrogenase, respectively. The beta-arbutin acting on the toxic trans-crotonaldehyde highlighted the potential of anti-skin cancer and provided a valuable clue for the new application of the beta-arbutin.
研究领域:
药学化学
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光谱学
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癌症研究
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产品关联
DOI
高影响因子
LUMINESCENCE
·
2020
·Vol. 36
·期 1
·35-44
·
IF 1.855
Hui Guo,Jiawen Xie,Tancong Liao,Xun Tuo
Donepezil (DNP) is one of approved drugs to treat Alzheimer's disease (AD). However, the potential effect of DNP on DNA is still unclear. Therefore, the interaction of DNP with calf thymus DNA (DNA) was studied in vitro using spectroscopic and molecular docking methods. Steady-state and transient fluorescence experiments showed that there was a clear binding interaction between DNP and DNA, resulting from DNP fluorescence being quenched using DNA. DNP and DNA have one binding site between them, and the binding constant (K b ) was 0.78 × 10 4 L·mol −1 at 298 K. In this binding process, hydrophobic force was the main interaction force, because enthalpy change (ΔH) and entropy change (ΔS) of DNP–DNA were 67.92 kJ·mol −1 and 302.96 J·mol −1 ·K −1 , respectively. DNP bound to DNA in a groove-binding mode, which was verified using a competition displacement study and other typical spectroscopic methods. Fourier transform infrared (FTIR) spectrum results showed that DNP interacted with guanine (G) and cytosine (C) bases of DNA. The molecular docking results further supported the results of spectroscopic experiments, and suggested that both Pi-Sigma force and Pi-Alkyl force were the major hydrophobic force functioning between DNP and DNA.
研究领域:
生物化学
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药物研究
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2022
·Vol. 15
·期 5
·1719
·
IF 3.748
Jingjing Wang,Junjie Ren,Qinglin Tang,Xinzhi Wang,Yao Wang,Yanxin Wang,Zhonglin Du,Wei Wang,Linjun Huang,Laurence A. Belfiore,Jianguo Tang
Copper (II) complexes containing mixed ligands were synthesized in dimethyl formamide (DMF). The intense cyan emission at an ambient temperature is observed for solid copper (II) complexes with salicylic acid and a 12% quantum yield with a fluorescent lifetime of approximately 10 ms. Hence, copper (II) complexes with salicylic acid are excellent candidates for photoactive materials. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) reveal that the divalent copper metal centers coordinate with the nitrogen and oxygen lone pairs of conjugate ligands. XPS binding energy trends for core electrons in lower-lying orbitals are similar for all three copper (II) complexes: nitrogen 1s and oxygen 1s binding energies increase relative to those for undiluted ligands, and copper 2p3/2binding energies decrease relative to that for CuCl2. The thermal behavior of these copper complexes reveals that the thermal stability is characterized by the following pattern: Cu(1,10-phenanthroline)(salicylic acid) > Cu(1,10-phenanthroline)(2,2’-bipyridine) > Cu(1,10-phenanthroline)(1-benzylimidazole)2.Keywords:copper (II) complex;luminescent materials;benzylimidazole;bipyridine;salicylic acid;spectroscopy
研究领域:
无机化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY
·
2016
·
IF 3.035
Jie-hua Shi,Dong-qi Pan,Xiou-xiou Wang,Ting-Ting Liu,Min Jiang,Qi Wang
Artemether (AMT), a peroxide sesquiterpenoides, has been widely used as an antimalarial for the treatment of multiple drug-resistant strains of plasmodium falciparum malaria . In this work, the binding interaction of AMT with bovine serum albumin (BSA) under the imitated physiological conditions (pH 7.4) was investigated by UV spectroscopy , fluorescence emission spectroscopy , synchronous fluorescence spectroscopy, Fourier transform infrared spectroscopy (FT-IR), circular dichroism (CD), three-dimensional fluorescence spectroscopy and molecular docking methods. The experimental results indicated that there was a change in UV absorption of BSA along with a slight red shift of absorption wavelength, indicating that the interaction of AMT with BSA occurred. The intrinsic fluorescence of BSA was quenched by AMT due to the formation of AMT–BSA complex. The number of binding sites ( n ) and binding constant of AMT–BSA complex were about 1 and 2.63 × 10 3 M − 1 at 298 K, respectively, suggesting that there was stronger binding interaction of AMT with BSA. Based on the analysis of the signs and magnitudes of the free energy change (Δ G 0 ), enthalpic change (Δ H 0 ) and entropic change (Δ S 0 ) in the binding process, it can be concluded that the binding of AMT with BSA was enthalpy-driven process due to | Δ H °| > | T Δ S °|. The results of experiment and molecular docking confirmed the main interaction forces between AMT and BSA were van der Waals force . And, there was a slight change in the BSA conformation after binding AMT but BSA still retains its secondary structure α-helicity. However, it had been confirmed that AMT binds on the interface between sub-domain IIA and IIB of BSA.
研究领域:
药理学
·
生物化学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
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