Influence of gold-bipyridyl derivants on aggregation and disaggregation of the prion neuropeptide PrP106-126.

Metal complexes can effectively inhibit the aggregation of amyloid peptides, such as Aβ, human islet amyloid polypeptide, and prion neuropeptide PrP106-126. Gold (Au) complexes exhibited better inhibition against PrP106-126 aggregation, particularly the Au-bipyridyl (bpy) complex; however, the role of different ligand configurations remains unclear. In the present study, three derivants of Au-bpy complexes, namely, [Au(Me2bpy)Cl2]Cl, [Au(t-Bu2bpy)Cl2]Cl, and [Au(Ph2bpy)Cl2]Cl, were investigated to determine their influence on the aggregation and disaggregation of PrP106-126.

Regulation of aggregation behavior and neurotoxicity of prion neuropeptides by platinum complexes.

Prion diseases belong to a group of infectious, fatal neurodegenerative disorders. The conformational conversion of a cellular prion protein (PrP(C)) into an abnormal misfolded isoform (PrP(Sc)) is the key event in prion disease pathology. PrP106-126 resembles PrP(Sc) in some physicochemical and biological characteristics, such as apoptosis induction in neurons, fibrillar formation, and mediation of the conversion of native cellular PrP(C) to PrP(Sc).

Stereochemistry of 4-hydroxyproline affects the conformation of conopeptides.

The cis/trans isomerization of 4-hydroxyproline is shown to remarkably affect the conformation of conopeptides with or without disulfide bonds.

Studies on the conformational change of adsorbed BSA onto a moderately hydrophobic surface at different denaturant concentrations and surface coverages.

This paper is aimed at investigating the conformational change of denatured bovine serum albumin (BSA) in combination with thermodynamic functions and their fractions, adsorption isotherms, Fourier transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC). Microcalorimetric measurements of displacement adsorption enthalpies DeltaH of denatured BSA (by guanidine hydrochloride (GuHCl)) adsorbed onto a moderately hydrophobic surface (PEG-600) from solutions were carried out. The contents of secondary structure elements of BSA in solutions and in the adsorbed state were determined by FTIR and the thermal stability of adsorbed BSA was measured by DSC.

Molecular dynamics simulation of a carboxy murine neuroglobin mutated on the proximal side: heme displacement and concomitant rearrangement in loop regions.

Neuroglobin, a member of vertebrate globin family, is distributed primarily in the brain and retina. Considerable evidence has accumulated regarding its unique ligand-binding properties, neural-specific distribution, distinct expression regulation, and possible roles in processes such as neuron protection and enzymatic metabolism. Structurally, neuroglobin enjoys unique features, such as bis-histidyl coordination to heme iron in the absence of exogenous ligand, heme orientational heterogeneity, and a heme sliding mechanism accompanying ligand binding.