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A study was conducted to explore the structural mechanism of [alpha]-chymotrypsinogen A (aCgn) aggregation which is critical for a number of amyloidosis disorders and the development of effective and safe biopharmaceuticals. Sufficiently strong extended [beta]-sheet interactions typical of the amyloid indicated that relatively small fraction of polypeptide sequence could drive formation of filamentous aggregates even under conditions favoring colloidal stability.

Transmission electron microscopy and Western blotting techniques were applied to evaluate the efficacy of hydralazine, and related hydrazides, in reducing amyloid [beta] (A[beta]) misfolding and A[beta] protein modification by the reactive lipid 4-hydroxy-2-nonenal (HNE). The results suggested that hydralazine would require specific chemical modifications for use as an AlzheimerEs disease (AD) therapeutic and its potential merit for further AD drug development.

The human homologue of rat eukaryotic initiation factor 2-associated glycoprotein, p67/MetAP2 was ectopically expressed in EGF-treated mouse embryonic NIH3T3 fibroblasts and C2C12 myoblasts and NIH3T3 cell lines expressing the constitutively active form of MAP kinase (MEK) to inhibit the activation and activity of extracellular signal-regulated kinases (ERK1/2) MAP kinases. The ability of ectopic expression of rat p67/MetAP2 in transformed cells to inhibit the tumorigenic phenotype by inhibiting the activation and activity of ERK1/2 MAP kinases confirmed the tumor suppression activity of p67/MetAP2

The thermal stability of full-length light chain (LC) and corresponding variable-joining [V.sub.L] and constant [C.sub.L] fragments are compared to assess the role of [C.sub.L] in fibrillogenesis. The full-length LCs are more likely to initiate aggregation instead of their fragments, during unfolding and provide a template for the [V.sub.L] deposition.

A range of biophysical techniques that includes differential scanning calorimetry and nuclear magnetic resonance spectroscopy are applied to characterize the structural and physicochemical properties and thermal unfolding of the amyloidogenic states of the protein. The overall results obtained provide a rational explanation for the atomic resolution of the initial events underlying amyloid formation by a globular protein.

The article discusses the various roles and applications of serum amyloid A (SAA), an acute phase protein. SAA is shown to be extremely beneficial for activating the peroxisome proliferator-activated receptor [gamma] through extracellularly regulated kinase 1/2 and COX-2 expression in hepatocytes.

The magic angle spinning NMR technique is employed to explain the structural characterization of the various GNNQQNY amyloid fibrils. The results demonstrate the presence of higher complexity in the fibril structure, as compared to the crystalline form of GNNQQNY.

The potential of mannose-containing glycopolymers to interact with human DC-SIGN and the ability of the glycopolymers to inhibit the interactions between DC-SIGN and the HIV envelope glycoprotein gp120 is examined. The studies have shown that a relatively simple glycopolymer has prevented the interactions between a human dendritic cell associated lectin (DC-SIGN) and the viral envelope glycoprotein gp120.

New glycosylated-L-lysine-N-carboxyanhydride (glycol-K NCA) monomers are prepared. These are the first living polymerizations of glycosylated NCAs and are used for preparing high molecular weight glycopolypeptides and block and statistical glycocopolypeptides.

The nucleation of distinct fibril morphologies is examined by using computer simulations of a simplified model of an amyloid polypeptide. The free-energy profiles of the aggregation process has shown that the nucleation barrier has determined the population fractions of different fibril morphologies, that is, amyloid polymorphism is under kinetic control.

A general strategy is described whereby two moderate inhibitors of amyloid formation is selected via kinetic assays and combined in trans to produce a highly effective inhibitor that has delayed the time to the appearance of amyloid and has reduced the total amount of amyloid formed. The approach is validated by using inhibitors of amyloid formation by islet amyloid polypeptide, the causative agent of amyloid formation in type 2 diabetes and the AlzheimerEs disease A[beta] peptide.

A series of molecular dynamics simulations of large-scale amyloid fibrils with local mutations that result in the disruption of the key intrapeptide salt bridge are reported. The results indicated that interactions mediated by side chains could be a potential target for novel approaches to drug design and the development of molecular therapies for amyloid disorders such as Alzheimer' s disease, through the chemical deactivation of key functional groups that are responsible for promoting the growth of the fibrils, chemical and mechanical stability and for furthering their aggregation in amyloid plaques.

A strategy is described for solving the high-resolution structure of amyloid fibrils by solid-state NMR and is used for determining the atomic-resolution structure of the prion domain of the fungal prion HET-s in its amyloid form. A comprehensive protocol is described by using six differently labeled samples, a collection of optimized solid-state NMR experiments and adapted structure calculation protocols.

Oligomers of the Alzheimer's amyloid [beta]-peptide A[[beta].sub.1-42] in an implicit membrane was designed to gain insight into the mechanism of amyloid toxicity. The results suggested that A[beta] pores might consist of tetrameric and hexameric [beta]-sheet subunits and these A[beta] pore models are consistent with the results of biophysical and biochemical experiments.

A study was conducted to demonstrate that the tea-derived flavanol, (-)-epigallocatechin 3-gallate [(2R,3R)-5,7-dihydroxy-2-(3,4,5-trihydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-3-yl 3,4,5-trihydroxybenzoate] (EGCG), is an effective inhibitor of in vitro Islet amyloid polypeptide (IAPP, amylin) amyloid formation and disaggregates preformed amyloid fibrils derived from IAPP. The findings for the behavior of IAPP which is similar to the reported interactions of A[beta] and [alpha]-synuclein with EGCG could be applied for the development of inhibitors of IAPP amyloid formation and compounds that disaggregate IAPP amyloid.

A library of randomly generated point mutants of islet amyloid polypeptide (IAPP) was generated to identify the aggregation-prone region(s). The method identified 22 single mutations, 4 double mutations, and 2 triple mutations of IAPP that appear to be less amyloidogenic than wild-type human IAPP.

Terahertz spectroscopy is employed to demonstrate the direct correlation between the protein antifreeze activity and long-range collective hydration dynamics which enable the survival of organisms living in subfreezing habitats. The hydration dynamics shift towards bulk water behavior is observed to strongly reduce the antifreeze glycoproteins (AFGPs) antifreeze activity.

The amyloid fibril formation reaction of the mouse prion protein at low pH is analyzed in the presence of various salts. The comparison of the rate constants measured from the changes in thioflavin T fluorescence, circular dichroism and dynamic light scattering has shown that conformational conversion has followed fibril elongation at low NaCl concentration and has followed fibril formation at high NaCl concentration.

The use of an anionic oligothipphene derivative (p-FTAA) for detecting prefibrillar protein aggregates during in vitro fibrillation of three different amyloidogenic proteins is analyzed. The results have highlighted the use of p-FTAA as an additional tool for analyzing the process of protein aggregation.

A site-specific magic angle spinning (MAS) NMR analysis of fibrils formed by the full-length [beta]m protein is described and the spectra of fibrils prepared under two different conditions are compared. The results have shown that the distinct macroscopic morphological features seen for the two types of fibrils have resulted from various in structure and dynamics at the molecular level.

A general synthetic strategy is described for the assembly of glycopolymers that capitalizes on the intrinsic of reducing glycans toward hydrazides to form stable cyclic N-glycosides. Glycopolymers containing biologically relevant branched oligosaccharides, such as sialyl [Lewis.sup.x], as well as sulfated glycosaminoglycan-like epitopes is prepared by using this method.

NMR relaxation measurements are used for addressing the kinetics of exchange between monomeric and large, polymorphic oligomeric species of amyloid [beta] (A[beta](1-40)). The increase in [super 15]N and [super 1][H.sub.N][R.sub.2] rates as a function of protein concentration is independent of nucleus and magnetic field and the fraction of peptide within the dark oligomeric state undergoing exchange with free monomer is calculated.

The crystal structure of the epigallocatechin 3-gallate-transthyretin (EGCG-V30M TTR) complex was characterized to demonstrate that EGCG as the major polyphenol component of green tea binds to TTR and suppresses TTR amyloid fibril formation. The study provides insight into the possible application of EGCG as a candidate compound for familial amyloid polyneuropathy (FAP) therapy.

A general-purpose methodology to predict the three-dimensional (3D) structures of trimeric asialoglycoprotein receptor (ASGP-R), which consists of human hepatic subunits (two subunits of H1 and one subunit of H2), bound to a triantennary oligosaccharide (TA) is presented. The study results provide detailed information about TA-ASGP-R interactions and the symmetry of the multivalent transmembrane complexes in the presence of their ligands.

A study was conducted to demonstrate the role of zinc found at millimolar concentrations in the secretory granule towards inhibition of human islet amyloid polypeptide (hIAPP) amyloid fibrillogenesis at concentrations similar to those found in the extracellular environment. The inhibition of the formation of aggregated and toxic forms of hIAPP by zinc provides insight into the possible mechanism for the linkage between deleterious mutations in the SLC30A8 zinc transporter, which transports zinc into the secretory granule, and type II diabetes.

Cryogenic electron microscopy is used to directly observe the nanostructural transformation from a twisted ribbon to a helical ribbon in supramolecular assemblies of peptide amphiphiles. The findings for the metastable states in the peptide aggregation could provide better insight into the amyloid-related diseases, such as Alzheimer's disease.

Various studies are conducted to explain the structural properties, as well as the dynamics of the stable nonfibrillar oligomers that are formed by the human prion protein (PrP) residues. These oligomers are shown to be highly associated with various neurodegenerative diseases.

A series of Teg12 structures bound to the desulfated cosubstrate 3'-phosphoadenosine 5'-phosphate, and bound to the teicoplanin aglycone are reported. The structural studies provide insight into importance of key catalytic residues and the residues found throughout the conformationally flexible loop regions in TEG during glycopeptide recruitment, binding and catalysis.

The UV resonance Raman spectroscopy technique is employed to study the various structural variations taking place in the cross-[beta] core of the amyloid [beta] fibrils. The conformations of the parallel and antiparallel [beta] sheets are shown to be completely different.

A combination of the real-time imaging and fluorescence correlation spectroscopy techniques is employed to explain the nucleation and growth observed in amyloid self-assembly. The analysis is shown to be extremely beneficial for the development of models for protein misfolding.

Surface-selective sum frequency generation (SFG) spectroscopy is used for examining kinetics of conformational changes of proteins at interfaces. The analysis of the achiral and chiral amide I spectra has shown that dipalmitoylphosphoglycerol (DPPG) has induced the misfolding of human islet amyloid polypeptide (hIAPP) from [alpha]-helical and random-coil structures to the parallel [beta]-sheet structure at the air/water interface.

A newly designed proteolytically stable retro-inverso peptide ((RI-OR2) inhibitor of [beta]-amyloid oligomerization is described. RI-OR2 significantly reversed the toxicity of A[beta](1-42) toward cultured SH-SY5Y neuroblastoma cells in two different cell toxicity assays and hence represent a strong candidate for further development as a novel treatment for Alzheimer's disease.

The mechanisms of enzymatic degradation of A[beta] with cross-[beta] structures and the series of steps involved in the digestion of A[beta] microfibrils to nanospheres or nanofilaments by protease XIV or [alpha]-chymotrypsin, respectively are reported. The degradation products which exhibit almost the same secondary structures but different cytotoxicities indicated that relationships between nanoassembled structures and cytotoxicity of A[beta] peptides are more significant than the [beta]-sheet content.