Molecular dynamics (MD) simulations were carried out for two-strand and ten-strand beta-sheets constructed from two peptides corresponding to the diverging turn of two homologous Abl-SH3 domains, DLSFMKGE (MK; from Drosophila) and DLSFKKGE (KK; from man), in explicit water at the temperatures of 30, 170/190 and 300 K. It was found that the 2 x MK beta-sheet is more stable than the 2 x KK beta-s...

Abeta peptides cleaved from the amyloid precursor protein are the main components of senile plaques in Alzheimer's disease. Abeta peptides adopt a conformation mixture of random coil, beta-sheet, and alpha-helix in solution, which makes it difficult to design inhibitors based on the 3D structures of Abeta peptides. By targeting the C-terminal beta-sheet region of an Abeta intermediate structure...

In this paper, the neural network method was applied to predict the content of protein secondary structure elements that was based on 'pair-coupled amino acid composition', in which the sequence coupling effects are explicitly included through a series of conditional probability elements. The prediction was examined by a self-consistency test and an independent-dataset. Both indicated good resu...

This paper describes the X-ray crystallographic structure of a designed cyclic beta-sheet peptide that forms a well-defined hydrogen-bonded dimer that mimics beta-sheet dimers formed by proteins. The 54-membered ring macrocyclic peptide (1a) contains molecular template and turn units that induce beta-sheet structure in a heptapeptide strand that forms the dimerization interface. The X-ray cryst...

The amino acid sequence rules that correspond to beta-sheet structures in proteins are still not well understood. Current protein structure prediction methods are more accurate for alpha-helical structures than for beta-sheet structures. One reason that beta-strand structure prediction is more difficult is because of its high prevalence of nonlocal interactions between regions of the protein ch...

The 3D solution structure of the GCC-box binding domain of a protein from Arabidopsis thaliana in complex with its target DNA fragment has been determined by heteronuclear multidimensional NMR in combination with simulated annealing and restrained molecular dynamic calculation. The domain consists of a three-stranded anti-parallel beta-sheet and an alpha-helix packed approximately parallel to t...

Two-dimensional NMR spectroscopy has been used to obtain sequence-specific 1H NMR assignments for the IgG-binding B2-domain of streptococcal protein G. Secondary structure elements were identified from analysis of characteristic backbone-backbone NOE patterns and amide proton exchange data. The B2-domain contains a four-stranded beta-sheet region in which the two inner strands form a parallel b...

Limited proteolysis of the scrapie prion protein (PrPSc) generates PrP 27-30, which polymerizes into amyloid. By attenuated total reflection-Fourier transform infrared spectroscopy, PrP 27-30 polymers contained 54% beta-sheet, 25% alpha-helix, 10% turns, and 11% random coil; dispersion into detergent-lipid-protein-complexes preserved infectivity and secondary structure. Almost 60% of the beta-s...

Transient two-dimensional infrared (2D IR) spectroscopy is used as a probe of protein unfolding dynamics in a direct comparison of fast unfolding experiments with molecular dynamics simulations. In the experiments, the unfolding of ubiquitin is initiated by a laser temperature jump, and protein structural evolution from nanoseconds to milliseconds is probed using amide I 2D IR spectroscopy. The...