Micro-FTIR and EPMA Characterisation of Charoite from Murun Massif (Russia)

Combined micro-Fourier transform infrared (micro-FTIR) and electron probe microanalyses (EPMA) were performed on a single crystal of charoite from Murun Massif (Russia) in order to get a deeper insight into the vibrational features of crystals with complex structure and chemistry. The micro-FTIR study of a single crystal of charoite was collected in the 6000–400 cm−1 at room temperature and after heating at 100°C. The structural complexity of this mineral is reflected by its infrared spectrum. The analysis revealed a prominent absorption in the OH stretching region as a consequence of band overlapping due to a combination of H2O and OH stretching vibrations. Several overtones of the O-H and Si-O stretching vibration bands were observed at about 4440 and 4080 cm−1 such as absorption possibly due to the organic matter at about 3000–2800 cm−1. No significant change due to the loss of adsorbed water was observed in the spectrum obtained after heating. The occurrence of well-resolved water bending vibration bands at about 1595 and 1667 cm−1 accounts for more than one structural water molecule as expected by charoite-90 polytype structure model from literature. The chemical composition of the studied crystal is close to the literature one.

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Complex structure and Mössbauer effect observed in the course of phase transitions in PbZr0.72Sn0.28O3 single crystal

The Journal of Chemical Physics ◽

10.1063/5.0032957 ◽

2020 ◽

Vol 153 (22) ◽

pp. 224202

Author(s):

Irena Jankowska-Sumara ◽

Mariola Kądziołka-Gaweł ◽

Maria Podgórna ◽

Andrzej Majchrowski ◽

Krystian Roleder

Keyword(s):

Phase Transitions ◽

Single Crystal ◽

Mössbauer Effect ◽

Complex Structure ◽

Mossbauer Effect

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Faculty Opinions recommendation of Transcription preinitiation complex structure and dynamics provide insight into genetic diseases.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.735802305.793571138 ◽

2020 ◽

Author(s):

Xiaolin Cheng

Keyword(s):

Genetic Diseases ◽

Complex Structure ◽

Preinitiation Complex ◽

Structure And Dynamics ◽

Insight Into

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Comparing the Efficiencies of the Removal of Cadmium from Industrial Wastewater Using Zeolites

International Research Journal of Pure and Applied Chemistry ◽

10.9734/irjpac/2020/v21i530166 ◽

2020 ◽

pp. 6-18

Author(s):

Michael Akrofi Anang ◽

Ruphino Zugle ◽

Baah Sefa- Ntiri

Keyword(s):

Rice Husk ◽

Industrial Wastewater ◽

Raw Materials ◽

Research Work ◽

Corn Stalk ◽

Zeolite X ◽

Bending Vibration ◽

Strong Peak ◽

Corn Husk ◽

Stretching Vibration

The presence of heavy metals in industrial wastewater needed to be removed in other to control pollution which has been caused as a result of human and industrial activities. Several adsorbents have been used for the remediation process but with this particular research work, Zeolites were used. They were synthesized hydrothermally from various locally available raw materials namely rice husk, corn stalk, corn husk, and kaolin. They were characterized using their FTIR to determine the functional groups on the material synthesized and also their adsorptive activities were compared with industrially synthesized Zeolite X. A very strong peak at 1052 cm-1 is as a result of the asymmetric vibrations of the internal T-O tetrahedron with a weak symmetric T-O stretching vibration recorded at 797 cm-1. Another strong peak was observed at 445 cm-1 as a result of the O-T-O bending vibration which confirms the presence of a five-membered structure. The adsorptive properties of the synthesized Zeolites were evaluated by using them to remove Cadmium ions from solution and their percentage removals were determined. Similarly, their adsorption kinetics were also determined and was observed the R2 values to be 0.9093 and 0.9454 for Corn husk and Cornstalk for the first order and the second order with R2 values of 1 for rice husk, kaolin and corn stalk.

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Addressing the Structural Complexity of Fluorinated Glucose Analogues: Insight into Lipophilicities and Solvation Effects

Chemistry - A European Journal ◽

10.1002/chem.202002825 ◽

2020 ◽

Vol 26 (59) ◽

pp. 13499-13506 ◽

Cited By ~ 2

Author(s):

Jacob St‐Gelais ◽

Émilie Côté ◽

Danny Lainé ◽

Paul A. Johnson ◽

Denis Giguère

Keyword(s):

Structural Complexity ◽

Solvation Effects ◽

Glucose Analogues ◽

Insight Into

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New Insight into Single-Crystal Silver Dendrite Formation and Growth Mechanisms

Crystal Growth & Design ◽

10.1021/acs.cgd.0c00953 ◽

2020 ◽

Vol 20 (11) ◽

pp. 7291-7299

Author(s):

Shahab Ranjbar Bahadori ◽

Linyu Mei ◽

Aseem Athavale ◽

Yu-jen Chiu ◽

Christopher S. Pickering ◽

...

Keyword(s):

Single Crystal ◽

Growth Mechanisms ◽

Dendrite Formation ◽

Insight Into

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Pyridoxal-5′-phosphate–dependent bifunctional enzyme catalyzed biosynthesis of indolizidine alkaloids in fungi

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1914777117 ◽

2019 ◽

Vol 117 (2) ◽

pp. 1174-1180 ◽

Cited By ~ 3

Author(s):

Guang Zhi Dai ◽

Wen Bo Han ◽

Ya Ning Mei ◽

Kuang Xu ◽

Rui Hua Jiao ◽

...

Keyword(s):

Polyketide Synthase ◽

Complex Structure ◽

Genome Mining ◽

Biosynthetic Gene Cluster ◽

Major Facilitator Superfamily ◽

Molecular Architecture ◽

Widespread Occurrence ◽

Indolizidine Alkaloids ◽

Major Facilitator ◽

Insight Into

Indolizidine alkaloids such as anticancer drugs vinblastine and vincristine are exceptionally attractive due to their widespread occurrence, prominent bioactivity, complex structure, and sophisticated involvement in the chemical defense for the producing organisms. However, the versatility of the indolizidine alkaloid biosynthesis remains incompletely addressed since the knowledge about such biosynthetic machineries is only limited to several representatives. Herein, we describe the biosynthetic gene cluster (BGC) for the biosynthesis of curvulamine, a skeletally unprecedented antibacterial indolizidine alkaloid from Curvularia sp. IFB-Z10. The molecular architecture of curvulamine results from the functional collaboration of a highly reducing polyketide synthase (CuaA), a pyridoxal-5′-phosphate (PLP)-dependent aminotransferase (CuaB), an NADPH-dependent dehydrogenase (CuaC), and a FAD-dependent monooxygenase (CuaD), with its transportation and abundance regulated by a major facilitator superfamily permease (CuaE) and a Zn(II)Cys6 transcription factor (CuaF), respectively. In contrast to expectations, CuaB is bifunctional and capable of catalyzing the Claisen condensation to form a new C–C bond and the α-hydroxylation of the alanine moiety in exposure to dioxygen. Inspired and guided by the distinct function of CuaB, our genome mining effort discovers bipolamines A−I (bipolamine G is more antibacterial than curvulamine), which represent a collection of previously undescribed polyketide alkaloids from a silent BGC in Bipolaris maydis ATCC48331. The work provides insight into nature’s arsenal for the indolizidine-coined skeletal formation and adds evidence in support of the functional versatility of PLP-dependent enzymes in fungi.

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Control of AlN single crystal nucleation: An insight into the crystal growth habit in the initial stages of the physical vapor transport method

Materials Express ◽

10.1166/mex.2015.1220 ◽

2015 ◽

Vol 5 (2) ◽

pp. 129-136 ◽

Cited By ~ 5

Author(s):

Lei Jin ◽

Hua-Yu Zhang ◽

Jie-Cai Han ◽

Chao-Liang Zhao ◽

Tai Yao ◽

...

Keyword(s):

Crystal Growth ◽

Single Crystal ◽

Growth Habit ◽

Vapor Transport ◽

Crystal Nucleation ◽

Physical Vapor Transport ◽

Transport Method ◽

Insight Into ◽

Vapor Transport Method

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Biphasic Force-Regulated Phosphorylation Site Exposure and Unligation of ERM Bound with PSGL-1: A Novel Insight into PSGL-1 Signaling via Steered Molecular Dynamics Simulations

International Journal of Molecular Sciences ◽

10.3390/ijms21197064 ◽

2020 ◽

Vol 21 (19) ◽

pp. 7064

Author(s):

Jingjing Feng ◽

Yan Zhang ◽

Quhuan Li ◽

Ying Fang ◽

Jianhua Wu

Keyword(s):

Molecular Dynamics ◽

Tensile Force ◽

Complex Structure ◽

Phosphorylation Site ◽

Steered Molecular Dynamics ◽

Structural Basis ◽

Quasi Equilibrium ◽

Dissociation Probability ◽

Transition Mechanism ◽

Insight Into

The PSGL-1-actin cytoskeleton linker proteins ezrin/radixin/moesin (ERM), an adaptor between P-selectin glycoprotein ligand-1 (PSGL-1) and spleen tyrosine kinase (Syk), is a key player in PSGL-1 signal, which mediates the adhesion and recruitment of leukocytes to the activated endothelial cells in flow. Binding of PSGL-1 to ERM initials intracellular signaling through inducing phosphorylation of Syk, but effects of tensile force on unligation and phosphorylation site exposure of ERM bound with PSGL-1 remains unclear. To answer this question, we performed a series of so-called “ramp-clamp” steered molecular dynamics (SMD) simulations on the radixin protein FERM domain of ERM bound with intracellular juxtamembrane PSGL-1 peptide. The results showed that, the rupture force of complex pulled with constant velocity was over 250 pN, which prevented the complex from breaking in front of pull-induced exposure of phosphorylation site on immunoreceptor tyrosine activation motif (ITAM)-like motif of ERM; the stretched complex structure under constant tensile forces <100 pN maintained on a stable quasi-equilibrium state, showing a high mechano-stabilization of the clamped complex; and, in consistent with the force-induced allostery at clamped stage, increasing tensile force (<50 pN) would decrease the complex dissociation probability but facilitate the phosphorylation site exposure, suggesting a force-enhanced biophysical connectivity of PSGL-1 signaling. These force-enhanced characters in both phosphorylation and unligation of ERM bound with PSGL-1 should be mediated by a catch-slip bond transition mechanism, in which four residue interactions on binding site were involved. This study might provide a novel insight into the transmembrane PSGL-1 signal, its biophysical connectivity and molecular structural basis for cellular immune responses in mechano-microenvironment, and showed a rational SMD-based computer strategy for predicting structure-function relation of protein under loads.

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