Inhibition of Aβ Aggregation by [TEA][Ms] Follows Weakening of the Hydrophobic Core and Sequestration of Peptides in Ionic Liquid Nanodomains.

We developed a coarse-grained model for the protic ionic liquid, triethylammonium mesylate ([TEA][Ms]), to characterize its inhibitory effects on amyloid aggregation using the KLVFFAE fragment of the amyloid-β (Aβ) as a model amyloidogenic peptide. In agreement with previous experiments, coarse-grained molecular dynamics simulations showed that increasing concentrations of [TEA][Ms] in aqueous media led to increasingly small Aβ aggregates with low beta-sheet contents. The cause of [TEA][Ms]'s inhibition of peptide aggregation was found to be a result of two interrelated effects.

Opposing roles of organic salts on mini-protein structure.

We investigated the effects of 1-ethyl-3-methylimidazolium chloride ([EMIM][Cl]) and choline chloride ([Chol][Cl]) on the local environment and conformational landscapes of Trp-cage and Trpzip4 mini-proteins using experimental and computational approaches. Fluorescence experiments and computational simulations revealed distinct behaviors of the mini-proteins in the presence of these organic salts. [EMIM][Cl] showed a strong interaction with Trp-cage, leading to fluorescence quenching and destabilization of its native structural interactions.

Folding and modulation of the helical conformation of Glycophorin A by point mutations.

Transmembrane helix folding and self-association play important roles in biological signaling and transportation pathways across biomembranes. With molecular simulations, studies to explore the structural biochemistry of this process have been limited to focusing on individual fragments of this process - either helix formation or dimerization. While at an atomistic resolution, it can be prohibitive to access long spatio-temporal scales, at the coarse grained (CG) level, current methods either employ additional constraints to prevent spontaneous unfolding or have a low resolution on sidechain beads that restricts the study of dimer disruption caused by mutations.

Transferable and Polarizable Coarse Grained Model for Proteins─ProMPT.

The application of classical molecular dynamics (MD) simulations at atomic resolution (fine-grained level, FG), to most biomolecular processes, remains limited because of the associated computational complexity of representing all the atoms. This problem is magnified in the presence of protein-based biomolecular systems that have a very large conformational space, and MD simulations with fine-grained resolution have slow dynamics to explore this space. Current transferable coarse grained (CG) force fields in literature are either limited to only peptides with the environment encoded in an implicit form or cannot capture transitions into secondary/tertiary peptide structures from a primary sequence of amino acids.

Clinical and epidemiological characteristics of children with COVID-19 in Selangor, Malaysia.

Objective: To describe the clinical and epidemiological characteristics of children diagnosed with coronavirus disease 2019 (COVID-19) at Hospital Sungai Buloh, Selangor, Malaysia.

Methods: A retrospective observational study was performed on children aged <12 years diagnosed with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection between January 25 and December 31, 2020. A comparative analysis was undertaken between asymptomatic and symptomatic children, as well as a sub-analysis of their caretakers' COVID-19 status.

Inhibition of peptidyl arginine deiminase, a virulence factor, by antioxidant-rich : and evaluation.

, the cause of periodontitis, is also linked to many systemic disorders due to its citrullination capability from a unique peptidyl arginine deiminase (PPAD). Protein citrullination is able to trigger an autoimmune response, increasing the severity of rheumatoid arthritis. The main objective of this study is to evaluate the inhibitory activity of leaves extract towards the PPAD and .

Recovery of enzyme structure and activity following rehydration from ionic liquid.

Long-term preservation of proteins at room temperature continues to be a major challenge. Towards using ionic liquids (ILs) to address this challenge, here we present a combination of experiments and simulations to investigate changes in lysozyme upon rehydration from IL mixtures using two imidazolium-based ILs (1-ethyl-3-methylimidazolium ethylsulfate, [EMIM][EtSO] and 1-ethyl-3-methylimidazolium diethylphosphate, [EMIM][EtPO]). Various spectroscopic experiments and molecular dynamics simulations are performed to ascertain the structure and activity of lysozyme.

Dual mechanism of ionic liquid-induced protein unfolding.

Ionic liquids (ILs) are gaining attention as protein stabilizers and refolding additives. However, varying degrees of success with this approach motivates the need to better understand fundamental IL-protein interactions. A combination of experiment and simulation is used to investigate the thermal unfolding of lysozyme in the presence of two imidazolium-based ILs (1-ethyl-3-methylimidazolium ethylsulfate, [EMIM][EtSO4] and 1-ethyl-3-methylimidazolium diethylphosphate, [EMIM][Et2PO4]).

In-Plane Deformation Mechanics for Highly Stretchable Electronics.

Scissoring in thick bars suppresses buckling behavior in serpentine traces that have thicknesses greater than their widths, as detailed in a systematic set of analytical and experimental studies. Scissoring in thick copper traces enables elastic stretchability as large as ≈350%, corresponding to a sixfold improvement over previously reported values for thin geometries (≈60%).

Electronic Properties of Cyclacenes from TAO-DFT.

Owing to the presence of strong static correlation effects, accurate prediction of the electronic properties (e.g., the singlet-triplet energy gaps, vertical ionization potentials, vertical electron affinities, fundamental gaps, symmetrized von Neumann entropy, active orbital occupation numbers, and real-space representation of active orbitals) of cyclacenes with n fused benzene rings (n = 4-100) has posed a great challenge to traditional electronic structure methods.