Empirical analyses of protein secondary structures based on circular dichroism (CD) and synchrotron radiation (SRCD) spectroscopic data rely the availability reference datasets comprised spectra relevant proteins, whose crystal have been determined. Datasets only soluble proteins not proven suitable for analysing membrane proteins.A new dataset, MP180, has created containing 30 encompassing structure fold space covered by all known structures. In addition a mixed SMP180, created, which...

New high-flux synchrotron radiation circular dichroism (SRCD) beamlines are providing important information for structural biology, but can potentially cause denaturation of the protein samples under investigation. This effect has been studied at new CD1 dedicated SRCD beamline ISA in Denmark, where radiation-induced thermal damage effects were observed, depending not only on flux also focal spot size light. Comparisons with similar studies other facilities worldwide lead to estimation a...

The hexameric Escherichia coli RNA chaperone Hfq (Hfq(Ec)) is involved in riboregulation of target mRNAs by small trans-encoded RNAs. proteins different bacteria comprise an evolutionarily conserved core, whereas the C-terminus variable length. Although structure core has been elucidated for several proteins, no structural information yet obtained C-terminus. Using bioinformatics, nuclear magnetic resonance spectroscopy, synchrotron radiation circular dichroism (SRCD) spectroscopy and angle...

New advances in instrumentation, demonstration of proof‐of‐principle studies, and development new tools methods for data analysis interpretation have enabled the technique Synchrotron Radiation Circular Dichroism (SRCD) spectroscopy to become a useful tool structural functional biology. This paper discusses characterisation two SRCD beamlines, CD1 at Institute Storage Rings (ISA), Denmark 4B8 Beijing Facility (BSRF), China, applications method examining biological systems.

This paper summarizes the results of experiments carried out over past 15 years in which low-pressure hysteresis adsorption organic vapours by porous carbons has been observed. These collected data provide substantial support for hypothesis that low pressure these systems is associated with intercalation molecules adsorbate narrow pore spaces leading to irreversible changes structure. Attention drawn close parallels between this type hysteresis, deformation structure forces exceeds elastic...

Valproic acid (VPA) is an anticonvulsant drug that also used to treat migraines and bipolar disorder. Its proposed biological targets include human voltage-gated sodium channels, among other membrane proteins. We the prokaryotic NavMs channel, which has been shown be a good exemplar for binding examine structural functional interactions of VPA. Thermal melt synchrotron radiation circular dichroism spectroscopic studies full-length channel (which includes both pore voltage sensor domains),...

Synchrotron radiation circular dichroism (SRCD) is an emerging technique in structural biology with particular value protein secondary structure analyses since it permits the collection of data down to much lower wavelengths than conventional (cCD) instruments. Reference database spectra collected on different SRCD instruments future as well current reference datasets derived from cCD must be compatible. Therefore there a need for standardization calibration methods ensure quality control....

Extramembranous domains play important roles in the structure and function of membrane proteins, contributing to protein stability, forming association domains, binding ancillary subunits ligands. However, these are generally flexible, making them difficult or unsuitable targets for obtaining high-resolution X-ray NMR structural information. In this study we show that highly sensitive method synchrotron radiation circular dichroism (SRCD) spectroscopy can be used as a powerful tool...

Synchrotron radiation circular dichroism (SRCD) spectroscopy is emerging as an important new tool in structural molecular biology. Previously we had shown that lower-flux SRCD instruments, such UV1 at ISA and beamline 3.1 the SRS, vacuum ultraviolet (VUV) damage to proteins was not evident after exposure over a period of hours. No effects were detected either protein primary or secondary structures. However, with development high-flux beamlines, CD12 this issue has been revisited because...

The authors report the ozonation of patterned, vertically aligned carbon nanotube (CNT) forests as a method priming them for subsequent pseudo atomic layer deposition (ψ-ALD) (alternating deposition) silica to produce microfabricated, CNT-templated thin chromatography (TLC) plates. Gas phase simplifies our scheme by replacing two steps in previous fabrication process: chemical vapor and ALD Al2O3, with this much more straightforward step. As shown x-ray photoelectron spectroscopy (XPS),...

Here, we report efficiencies up to 112 000 plates per meter (a reduced plate height, h, of 2.22) for RP, carbon/nanodiamond/aminopolymer particles using conventional injection conditions in HPLC. This efficiency greatly exceeds our best previously reported value 71 N/m (h = 3.52). The carbon cores used this study were derived from carbonized poly(divinylbenzene) spheres that either made in-house by a two-step polymerization procedure or obtained commercially. resulting showed good uniformity...

The hepatitis C virus (HCV) encodes the p7 protein that oligomerizes to form an ion channel. 63 amino acid long monomer is integral membrane predominantly found in endoplasmic reticulum (ER). Although it currently unknown whether incorporated into secreted virions, its presence crucial for release of infectious virus. molecular and biophysical mechanism employed by channel largely unknown, but vivo likely be embedded membranes undergoing changes lipid composition. In this study we analyze...

The effects of iron catalyst thickness on the fabrication and performance microfabricated, binder-free, carbon nanotube (CNT)-templated, thin layer chromatography (TLC) plates are demonstrated. was deposited at thicknesses ranging from 4 to 18 nm in increments 2 nm. Its plays a key role governing integrity separation capabilities microfabricated TLC plates, as determined using test dye mixture. Atomic force microscopy scanning electron show that smaller more numerous nanoparticles formed...

Abstract Background Circular Dichroism (CD) spectroscopy is a widely used method for studying protein structures in solution. Modern synchrotron radiation CD (SRCD) instruments have considerably higher photon fluxes than do conventional lab-based instruments, and hence the ability to routinely measure data much lower wavelengths. Recently new reference dataset of SRCD spectra proteins known structure, designed cover secondary structure fold space, has been produced which includes low...

Three mixed-mode high-performance liquid chromatography columns packed with superficially porous carbon/nanodiamond/amine-polymer particles were used to separate mixtures of cannabinoids. Columns evaluated included: (i) reversed phase (C18 ), weak anion exchange, 4.6 × 33 mm, 3.6 μm, and 100 (ii) phase, strong exchange (quaternary amine), 4.6×33 (iii) hydrophilic interaction chromatography, 150 μm. Different selectivities achieved under various mobile stationary conditions. Efficiencies peak...

Asparagine is conserved in the S6 transmembrane segments of all voltage-gated sodium, calcium, and TRP channels identified to date. A broad spectrum channelopathies including cardiac arrhythmias, epilepsy, muscle diseases, pain disorders associated with its mutation. To investigate effects on sodium channel functional properties, we mutated simple prokaryotic NaChBac. Electrophysiological characterization N225D mutant reveals that this conservative substitution shifts voltage-dependence...

Multi-domain voltage-gated ion channels appear to have evolved through sequential rounds of intragenic duplication from a primordial one-domain precursor. Whereas modularity within symmetrical is established, little known about the roles individual regions more complex asymmetrical where domains undergone substantial divergence. Here we isolated and characterised both divergent pore human TPC2, two-domain channel that holds key intermediate position in evolution channels. In HeLa cells, each...

The protein calexcitin was originally identified in molluscan photoreceptor neurons as a 20 kDa molecule which up-regulated and phosphorylated following Pavlovian conditioning protocol. Subsequent studies showed that regulates the voltage-dependent potassium channel calcium-dependent well causing release of calcium ions from endoplasmic reticulum (ER) by binding to ryanodine receptor. A crystal structure squid Loligo pealei fold is similar another signalling protein, calmodulin, N-...