Conformational Modularity of an Abiotic Secondary-Structure Motif in Aqueous Solution

Abstract Silver nanoparticles have antimicrobial properties since they can be regarded as an efficient protector against pathogenic microorganisms. Fourier transform infrared spectroscopy was used to examine conformational changes in the secondary structure of wheat gluten washed out from grain treated with an aqueous solution of silver nanoparticles stabilized by tri-sodium citrate. Silver nanoparticles were used as a protective layer on the grain surface against bacterial and fungal infections (antimicrobial agent). Analysis of the amide I band revealed significant changes in the secondary structure after using silver nanoparticles. An increase in the β-sheet content (from 36.2 to 39.2%) was observed at the expense of the α-helix and β-turn content. To find factors causing these changes, the wheat grains were treated by an aqueous solution of trisodium citrate and water. The results obtained indicate that the changes in the gluten structure were connected mainly with the trisodium citrate action due to presence of a small number of free molecules of the stabilizer in the solution of silver nanoparticles. Additionally, the conformational changes in gluten pointed out that gluten flexibility increased (decrease in the αH/βS ratio from 1.40 for the control sample to 1.26 for the silver nanoparticle-treated samples) as well as the solubility of gluten decreased (decrease in the β-turn content from 13.1 to 11.4%).

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Molecular Dynamics Study on an Adipokinetic Hormone Peptide in Aqueous Solution

Zeitschrift für Naturforschung C ◽

10.1515/znc-2000-1-223 ◽

2000 ◽

Vol 55 (1-2) ◽

pp. 125-128 ◽

Cited By ~ 3

Author(s):

Igor Z. Zubrzycki

Keyword(s):

Molecular Dynamics ◽

Aqueous Solution ◽

Molecular Dynamics Simulation ◽

Secondary Structure ◽

Room Temperature ◽

Dynamics Simulation ◽

Red Pigment ◽

Adipokinetic Hormone ◽

Extended Conformation ◽

Flying Insects

Lom-AKH-I is a member of the adipokinetic hormone/ red pigment concentrating hormone (AKH / RPCH) family of peptides found in flying insects. A molecular dynamics simulation at room temperature (293 K) in water has been performed to survey the folding path of the Lom-AKH-I peptide in water and to establish the secondary structure of Lom-AKH-I. The obtained results indicate the presence of an undefined extended conformation.

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Molecular Dynamics Study To Investigate the Effect of Chemical Substitutions of Methionine 35 on the Secondary Structure of the Amyloid β (Aβ(1−42)) Monomer in Aqueous Solution

The Journal of Physical Chemistry B ◽

10.1021/jp0771872 ◽

2008 ◽

Vol 112 (7) ◽

pp. 2159-2167 ◽

Cited By ~ 26

Author(s):

Luciano Triguero ◽

Rajiv Singh ◽

Rajeev Prabhakar

Keyword(s):

Molecular Dynamics ◽

Aqueous Solution ◽

Secondary Structure ◽

Amyloid Β ◽

Methionine 35

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Interaction between Negatively Charged Fish Gelatin and Cyclodextrin in Aqueous Solution: Characteristics and Formation Mechanism

Gels ◽

10.3390/gels7040260 ◽

2021 ◽

Vol 7 (4) ◽

pp. 260

Author(s):

Qi Fang ◽

Nao Ma ◽

Keying Ding ◽

Shengnan Zhan ◽

Qiaoming Lou ◽

...

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Secondary Structure ◽

Hydrogen Bonds ◽

Gel Strength ◽

Random Coil ◽

Fish Gelatin ◽

Intermolecular Hydrogen Bonds ◽

Hydrophobic Residues ◽

Conformation Transitions

The effect that ratios of fish gelatin (FG) to α/β/γ cyclodextrins (α, β, γCDs) had on the phase behavior of a concentrated biopolymer mixture were comparatively investigated. This showed that the formed biopolymer mixture had the highest gel strength at ratios of FG–CD = 90:10. FG could interact with CDs to form stable soluble complexes with lower values of turbidity, particle size and ζ-potential. All of the FG–CD mixture solutions exhibited pseudo-plastic behaviors, and FG–αCD samples had the highest viscosity values than others. The addition of CDs could unfold FG molecules and make conformation transitions of FG from a random coil to β-turn, leading to the environmental change of hydrophobic residues and presenting higher fluorescence intensity, especially for βCDs. FTIR results revealed that the formation of intermolecular hydrogen bonds between FG and CD could change the secondary structure of FG. These findings might help further apply FG–CD complexes in designing new food matrixes.

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Effect of pH on the Conformational Transition of Silk Fibroin in Aqueous Solution Monitored by Thioflavin-T Fluorescence

10.21203/rs.3.rs-699204/v1 ◽

2021 ◽

Author(s):

Ben Jia ◽

Lan Jia ◽

Jingxin Zhu

Keyword(s):

Aqueous Solution ◽

Secondary Structure ◽

Silk Fibroin ◽

Conformational Transition ◽

Thioflavin T ◽

Random Coil ◽

Fluorescence Dye ◽

Assembly Behavior ◽

Β Sheet

Abstract In this work, the potential application of the fluorescence dye Thioflavin-T (ThT), which can specifically bind to amyloid, as a powerful tool for monitoring secondary structure transitions of silk fibroin (SF) induced by pH was examined. Results showed that ThT emission intensities substantially increased when pH decreased from 6.8 to 4.8. This increase may be due to conformational transitions from random coil to β-sheet. The morphology and secondary structure of SF were also investigated via TEM, AFM and circular dichroism spectroscopy. The information obtained herein can be utilized not only for the development of convenient and efficient noninvasive method for monitoring the assembly behavior of SF in aqueous solution but also for in vitro fluorescence imaging.

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The stability of secondary structure in aqueous solution

Journal de Chimie Physique ◽

10.1051/jcp/1991882626 ◽

1991 ◽

Vol 88 ◽

pp. 2626-2626

Author(s):

CL Brooks III ◽

DJ Tobias

Keyword(s):

Aqueous Solution ◽

Secondary Structure ◽

The Stability

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Role of hydrophobic residues for the gaseous formation of helical motifs

Chemical Communications ◽

10.1039/c9cc01898k ◽

2019 ◽

Vol 55 (35) ◽

pp. 5147-5150 ◽

Cited By ~ 3

Author(s):

Lin Liu ◽

Xin Dong ◽

Yichang Liu ◽

Nicklas Österlund ◽

Astrid Gräslund ◽

...

Keyword(s):

Mass Spectrometry ◽

Aqueous Solution ◽

Secondary Structure ◽

Gas Phase ◽

Hydrophobic Residues ◽

Secondary Structure Content

The secondary structure content of proteins and their complexes may change significantly on passing from aqueous solution to the gas phase (as in mass spectrometry experiments).

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