Direct Detection of Bound Water in Hydrated Powders of Lysozyme by Differential Scanning Calorimetry.

While exploring the behavior of lysozyme powders at different percentages of rehydration by differential scanning calorimetry, we noticed a small peak persistently on the left of the melting point of bulk water, which, when heating up the system, was always around -10 °C. The intensity of the transition was maximal at 160% rehydration and disappeared at higher values. By comparing the premelting peak properties in HO and DO, we attributed it to freezable water bound on the protein surface.

Online self-evaluation of fMRI-based neurofeedback performance.

This study explores the subjective evaluation of supplementary motor area (SMA) regulation performance in a real-time functional magnetic resonance imaging neurofeedback (fMRI-NF) task. In fMRI-NF, people learn how to self-regulate their brain activity by performing mental actions to achieve a certain target level (TL) of blood-oxygen-level-dependent (BOLD) activation. Here, we studied two types of self-evaluation: performance predictions and perceived confidence in the prediction judgement.

Accessing self-diffusion on nanosecond time and nanometre length scales with minute kinetic resolution.

Neutron spectroscopy uniquely and non-destructively accesses diffusive dynamics in soft and biological matter, including for instance proteins in hydrated powders or in solution, and more generally dynamic properties of condensed matter on the molecular level. Given the limited neutron flux resulting in long counting times, it is important to optimize data acquisition for the specific question, in particular for time-resolved (kinetic) studies. The required acquisition time was recently significantly reduced by measurements of discrete energy transfers rather than quasi-continuous neutron scattering spectra on neutron backscattering spectrometers.

Residual Membrane Fluidity in Mycobacterial Cell Envelope Layers under Extreme Conditions Underlines Membrane-Centric Adaptation.

One of the routes for adaptation to extreme environments is via remodeling of cell membrane structure, composition, and biophysical properties rendering a functional membrane. Collective studies suggest some form of membrane feedback in mycobacterial species that harbor complex lipids within the outer and inner cell wall layers. Here, we study the homeostatic membrane landscape of mycobacteria in response to high hydrostatic pressure and temperature triggers using high pressure fluorescence, mass and infrared spectroscopies, NMR, SAXS, and molecular dynamics simulations.

Bereavement care guidelines used in health care facilities immediately following perinatal loss: a scoping review.

Objective: The objective of the scoping review was to explore the evidence and describe what is known about perinatal bereavement care guidelines provided within health care facilities prior to discharge. Additionally, the review sought to identify what is known about parents' mental health outcomes, and map these outcomes to the characteristics of the bereavement care guidelines.

Introduction: Perinatal loss poses a serious risk of emotional trauma and mental health sequelae.

Dynamic Personality of Proteins and Effect of the Molecular Environment.

Protein dynamics display distinct traits that are linked to their specific biological function. However, the interplay between intrinsic dynamics and the molecular environment on protein stability remains poorly understood. In this study, we investigate, by incoherent neutron scattering, the subnanosecond time scale dynamics of three model proteins: the mesophilic lysozyme, the thermophilic thermolysin, and the intrinsically disordered β-casein.

H, C and N backbone and side-chain resonance assignments of the human oncogenic protein NCYM.

NCYM is a cis-antisense gene of MYCN oncogene and encodes an oncogenic protein that stabilizes MYCN via inhibition of GSK3b. High NCYM expression levels are associated with poor clinical outcomes in human neuroblastomas, and NCYM overexpression promotes distant metastasis in animal models of neuroblastoma. Using vacuum-ultraviolet circular dichroism and small-angle X-ray scattering, we previously showed that NCYM has high flexibility with partially folded structures; however, further structural characterization is required for the design of anti-cancer agents targeting NCYM.

Decoding the Role of the Global Proteome Dynamics for Cellular Thermal Stability.

Molecular mechanisms underlying the thermal response of cells remain elusive. On the basis of the recent result that the short-time diffusive dynamics of the proteome is an excellent indicator of temperature-dependent bacterial metabolism and death, we used neutron scattering (NS) spectroscopy and molecular dynamics (MD) simulations to investigate the sub-nanosecond proteome mobility in psychro-, meso-, and hyperthermophilic bacteria over a wide temperature range. The magnitude of thermal fluctuations, measured by atomic mean square displacements, is similar among all studied bacteria at their respective thermal cell death.

Effects of Crowding and Cosolutes on Biomolecular Function at Extreme Environmental Conditions.

The extent of the effect of cellular crowding and cosolutes on the functioning of proteins and cells is manifold and includes the stabilization of the biomolecular systems, the excluded volume effect, and the modulation of molecular dynamics. Simultaneously, it is becoming increasingly clear how important it is to take the environment into account if we are to shed light on biological function under various external conditions. Many biosystems thrive under extreme conditions, including the deep sea and subseafloor crust, and can take advantage of some of the effects of crowding.

Membrane plasticity induced by -inositol derived archaeal lipids: chemical synthesis and biophysical characterization.

Archaeal membrane lipids have specific structures that allow Archaea to withstand extreme conditions of temperature and pressure. In order to understand the molecular parameters that govern such resistance, the synthesis of 1,2-di--phytanyl--3-phosphoinositol (DoPhPI), an archaeal lipid derived from -inositol, is reported. Benzyl protected -inositol was first prepared and then transformed to phosphodiester derivatives using a phosphoramidite based-coupling reaction with archaeol.

Imaging the columnar functional organization of human area MT+ to axis-of-motion stimuli using VASO at 7 Tesla.

Cortical columns of direction-selective neurons in the motion sensitive area (MT) have been successfully established as a microscopic feature of the neocortex in animals. The same property has been investigated at mesoscale (<1 mm) in the homologous brain area (hMT+, V5) in living humans by using ultra-high field functional magnetic resonance imaging (fMRI). Despite the reproducibility of the selective response to axis-of-motion stimuli, clear quantitative evidence for the columnar organization of hMT+ is still lacking.

Molecular Rearrangements in Protomembrane Models Probed by Laurdan Fluorescence.

Lipid membranes are a key component of living systems and have been essential to the origin of life. One hypothesis for the origin of life assumes the existence of protomembranes with ancient lipids formed by Fischer-Tropsch synthesis. We determined the mesophase structure and fluidity of a prototypical decanoic (capric) acid-based system, a fatty acid with a chain length of 10 carbons, and a lipid system consisting of a 1:1 mixture of capric acid with a fatty alcohol of equal chain length (C10 mix).

Diffusive Dynamics of Bacterial Proteome as a Proxy of Cell Death.

Temperature variations have a big impact on bacterial metabolism and death, yet an exhaustive molecular picture of these processes is still missing. For instance, whether thermal death is determined by the deterioration of the whole or a specific part of the proteome is hotly debated. Here, by monitoring the proteome dynamics of , we clearly show that only a minor fraction of the proteome unfolds at the cell death.

Incorporation and localisation of alkanes in a protomembrane model by neutron diffraction.

Protomembranes at the origin of life were likely composed of short-chain lipids, readily available on the early Earth. Membranes formed by such lipids are less stable and more permeable under extreme conditions, so a novel membrane architecture was suggested to validate the accuracy of this assumption. The model membrane includes the presence of a layer of alkanes in the mid-plane of the protomembrane in between the two monolayer leaflets and lying perpendicular to the lipid acyl chains.

Intracranial human recordings reveal association between neural activity and perceived intensity for the pain of others in the insula.

Based on neuroimaging data, the insula is considered important for people to empathize with the pain of others. Here, we present intracranial electroencephalographic (iEEG) recordings and single-cell recordings from the human insula while seven epilepsy patients rated the intensity of a woman's painful experiences seen in short movie clips. Pain had to be deduced from seeing facial expressions or a hand being slapped by a belt.

Hippocampal activity in working memory tasks: sparse, yet relevant.

Recent studies suggest the hippocampus is involved in working memory (WM). Slotnick (this issue) critically reviewed relevant fMRI findings and concludes WM 'does not activate the hippocampus.' We extend Slotnick's review by discussing observations from human intracranial and lesion research.

Sub-Nanosecond Dynamics of Pathologically Relevant Bio-Macromolecules Observed by Incoherent Neutron Scattering.

Incoherent neutron scattering (iNS) is one of the most powerful techniques to study the dynamical behavior of bio-macromolecules such as proteins and lipid molecules or whole cells. This technique has widely been used to elucidate the fundamental aspects of molecular motions that manifest in the bio-macromolecules in relation to their intrinsic molecular properties and biological functions. Furthermore, in the last decade, iNS studies focusing on a possible relationship between molecular dynamics and biological malfunctions, i.

Unravelling the Adaptation Mechanisms to High Pressure in Proteins.

Life is thought to have appeared in the depth of the sea under high hydrostatic pressure. Nowadays, it is known that the deep biosphere hosts a myriad of life forms thriving under high-pressure conditions. However, the evolutionary mechanisms leading to their adaptation are still not known.

Fiber Diffraction and Small-Angle Scattering for Structural Investigation of Bacterial Amyloids.

X-ray/neutron fiber diffraction and small-angle X-ray/neutron scattering are widely used to investigate the molecular structure of fibrous proteins, including amyloid fibrils. However, there is sometimes confusion between these two techniques despite the fact that sample conditions and the content of the information obtained are not the same. In this brief chapter, we present the differences in sample conditions between these two methods, and their effects on experimentally obtained diffraction or scattering patterns, emphasizing the degree of disorder in the samples.

Structural Information on Bacterial Amyloid and Amyloid-DNA Complex Obtained by Small-Angle Neutron or X-Ray Scattering.

Small-angle scattering is a powerful technique to obtain structural information on biomacromolecules in aqueous solution at the sub-nanometer and nanometer length scales. It provides the sizes and overall shapes of the scattering particles. While small-angle X-ray scattering (SAXS) has often been used for structural analysis of a single-component system, small-angle neutron scattering (SANS) has been used to reveal the internal organization of a multicomponent system such as protein-protein and protein-DNA complexes.

High temperature molecular motions within a model protomembrane architecture.

Modern phospholipid membranes are known to be in a functional, physiological state, corresponding to the liquid crystalline phase, only under very precise external conditions. The phase is characterised by specific lipid motions, which seem mandatory to permit sufficient flexibility and stability for the membrane. It can be assumed that similar principles hold for proto-membranes at the origin of life although they were likely composed of simpler, single chain fatty acids and alcohols.

The dynamical Matryoshka model: 2. Modeling of local lipid dynamics at the sub-nanosecond timescale in phospholipid membranes.

Biological membranes are generally formed by lipids and proteins. Often, the membrane properties are studied through model membranes formed by phospholipids only. They are molecules composed by a hydrophilic head group and hydrophobic tails, which can present a panoply of various motions, including small localized movements of a few atoms up to the diffusion of the whole lipid or collective motions of many of them.