Abstract：
:Folding and self-assembly of amyloid beta (Abeta) peptide are linked to Alzheimer's disease. To understand the initial stage of amyloid-beta peptide aggregation, conformational characteristics of monomers of wild-type (WT) Abeta(28-35) and its mutant peptides A30G and A30I were investigated using density functional theory calculations and experimental studies. Monomeric structures and their relative stabilities were obtained on the basis of systematic structural optimization in the gas-phase and in the aqueous medium. Computations were performed by hybrid Hartree-Fock-Density Functional Theory (HF-DFT) at B3LYP/6-31G * level. Experimentally, the conformational transitions in the early stages of the octapeptide Abeta(28-35) and its mutants A30G and A30I in solution were characterized by CD, Thioflavin assay and FRET spectroscopy. Examination of the secondary structures revealed that Abeta(28-35) and its mutant monomers exist in random coil conformation in the aqueous medium in agreement with the theoretical predictions, which upon aging is transformed to sheet with different kinetics. This study deals with the structurally important intermediates and it may help to understand the mechanism of amyloid fibril aggregation leading to the onset of Alzheimer's disease.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Nagarajan S,Rajadas J,Malar EJdoi
10.1016/j.jsb.2010.02.017subject
Has Abstractpub_date
2010-06-01 00:00:00pages
439-50issue
3eissn
1047-8477issn
1095-8657pii
S1047-8477(10)00064-Xjournal_volume
170pub_type
杂志文章abstract：:We have shown by in vitro development of staged follicles in the presence of tritiated proline, as well as by immunoblot analysis, that the Dvs19 and DVS15 chorion proteins of Drosophila virilis are synthesized by the follicular epithelium and are incorporated in the chorion at the terminal stages of choriogenesis. Li...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1998.4999
更新日期：1998-10-01 00:00:00
abstract：:We have studied two members of the family of morphogenetic factors or chaperonins, the GroEL-like factors from Escherichia coli and Bacillus subtilis, in order to determine the possible structural basis of their related function in promoting the correct and efficient assembly of biological oligomers. The main objectiv...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/1047-8477(91)90071-4
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abstract：:The collagen which forms the egg case of the dogfish, Scyliorhinus canicula, is assembled in a three-dimensional network that results in a very resistant capsule. The capsule presumably accomplishes both a protective and a filtering role for the embryo contained within it. In the present work we have obtained electron...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1998.3994
更新日期：1998-01-01 00:00:00
abstract：:The structures of the compact and swollen southern bean mosaic virus (SBMV) particles have been compared by X-ray diffraction and proton magnetic resonance (PMR). Small-angle X-ray scattering showed that removal of divalent cations at alkaline pH causes the particle diameter to increase from 289Å in the native SBMV by...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2017.06.003
更新日期：2017-12-01 00:00:00
abstract：:In fishes, like in amphibians, it is well established that variations in rRNA activity occur during oogenesis. Contrary to amphibians, however, little is known about the ultrastructural changes of the nucleolus during fish oogenesis. Evolution of the nucleolus has been followed during oogenesis in the teleost fish Bar...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2005.07.006
更新日期：2005-10-01 00:00:00
abstract：:The aim of this work was to develop a protocol for automated tracking of actin filaments in electron tomograms of lamellipodia embedded in negative stain. We show that a localized version of the Radon transform for the detection of filament directions enables three-dimensional visualizations of filament network archit...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2012.02.011
更新日期：2012-04-01 00:00:00
abstract：:The crystal structure of the YckF protein from Bacillus subtilis was determined with MAD phasing and refined at 1.95A resolution. YckF forms a tight tetramer both in crystals and in solution. Conservation of such oligomerization in other phosphate sugar isomerases indicates that the crystallographically observed tetra...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2004.04.006
更新日期：2004-10-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2009.07.019
更新日期：2009-12-01 00:00:00
abstract：:The sulfur-oxidizing enzyme system (Sox) of the chemotroph Paracoccus pantotrophus is composed of several proteins, which together oxidize hydrogen sulfide, sulfur, thiosulfate or sulfite and transfers the gained electrons to the respiratory chain. The hetero-dimeric cytochrome c complex SoxXA functions as heme enzyme...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2005.09.002
更新日期：2005-12-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2009.10.007
更新日期：2010-03-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2010.09.002
更新日期：2011-02-01 00:00:00
abstract：:The Dugesia japonica vasa-like gene B (DjVLGB) protein is a DEAD-box RNA helicase of a planarian, which is well known for its strong regenerative capacity. DjVLGB shares sequence similarity to the Drosophila germ-line-specific DEAD-box RNA helicase Vasa, and even higher similarity to its paralogue, mouse PL10. In this...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2005.01.006
更新日期：2005-04-01 00:00:00
abstract：:Three-dimensional reconstruction of large macromolecules like viruses at resolutions below 10 A requires a large set of projection images. Several automatic and semi-automatic particle detection algorithms have been developed along the years. Here we present a general technique designed to automatically identify the p...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2003.11.028
更新日期：2004-01-01 00:00:00
abstract：:Like in most Crustacea, the cuticle of terrestrial isopods is hardened by a calcareous mineral phase. This rigid cuticle is frequently shed during a process called moulting. To reduce calcium loss, Porcellio scaber eats the shed cuticle, the exuviae, and absorb the calcium from it through large tubular diverticula of ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107613
更新日期：2020-11-01 00:00:00
abstract：:The microstructure and its crystallographic aspect of the shell of a limpet, Lottiakogamogai, have been investigated, as the first step to clarify the mechanism of shell formation in limpet. The shell consists of five distinct layers stacked along the shell thickness direction. Transmission electron microscopy (TEM) w...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2010.04.008
更新日期：2010-08-01 00:00:00
abstract：:MDPP is a fully featured general-purpose image processing package primarily written to support research in structural biology using data gathered by electron microscopy. It has focused on the analysis of images using Fourier techniques, particularly periodic plane-layer and helical structures, but has extensive tools ...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1006/jsbi.1996.0007
更新日期：1996-01-01 00:00:00
abstract：:Commonly employed data models for maximum likelihood refinement of electron microscopy images behave poorly in the presence of normalization errors. Small variations in background mean or signal brightness are relatively common in cryo-electron microscopy data, and varying signal-to-noise ratios or artifacts in the im...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2009.02.007
更新日期：2009-05-01 00:00:00
abstract：:Upon illumination the visual receptor rhodopsin (Rho) transitions to the activated form Rho(∗), which binds the heterotrimeric G protein, transducin (Gt) causing GDP to GTP exchange and Gt dissociation. Using succinylated concanavalin A (sConA) as a probe, we visualized native Rho dimers solubilized in 1mM n-dodecyl-β...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2013.02.014
更新日期：2013-05-01 00:00:00
abstract：:CTFFIND is a widely-used program for the estimation of objective lens defocus parameters from transmission electron micrographs. Defocus parameters are estimated by fitting a model of the microscope's contrast transfer function (CTF) to an image's amplitude spectrum. Here we describe modifications to the algorithm whi...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2015.08.008
更新日期：2015-11-01 00:00:00
abstract：:The central shaft of a bird's flight feather bears most of the aerodynamic load during flight and exhibits some remarkable mechanical properties. The shaft comprises two parts, the calamus and the rachis. The calamus is at the base of the shaft, while the rachis is the longer upper part which supports the vanes. The s...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107529
更新日期：2020-07-01 00:00:00
abstract：:The question as to whether keratin intermediate filaments (KIF) are built from a unique "building block" consisting of a pair of coiled-coil molecules has been studied by examining the earliest stages of reassembly of mouse K1/K10 KIF in vitro. Particles formed in protein solutions of about 45 micrograms/ml (near or b...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/1047-8477(91)90020-w
更新日期：1991-10-01 00:00:00
abstract：:The hyaluronate receptor CD44 plays role in cell adhesion and migration and is involved in tumor metastasis. The extracellular domain of CD44 comprises the hyaluronate-binding domain (HABD) and the membrane-proximal stem region; the short intracellular portion interacts with adaptor proteins and triggers signaling pat...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2015.06.005
更新日期：2015-08-01 00:00:00
abstract：:A characteristic feature of the dense phases formed by fiber-shaped molecules is their organization into parallel rods packed in a hexagonal or pseudo-hexagonal lateral network. This is typically the case for the collagen triple helices inside fibrils, as confirmed by recent X-ray diffraction experiments carried out o...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2010.11.018
更新日期：2011-02-01 00:00:00
abstract：:In order to understand further the mechanism of bone fracture repair, and thus to innovate better operative treatment for bone fracture and to design new implant materials for bone repair, microstructures of external periosteal callus (EPC) of repaired femoral fracture in both children and adults were investigated by ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1996.0084
更新日期：1996-11-01 00:00:00
abstract：:The dyneins are a family of microtubule motor proteins. The motor domain, which represents the C-terminal 2/3 of the dynein heavy chain, exhibits homology to the AAA family of ATPases. It consists of a ring of six related but divergent AAA+ units, with two substantial sized protruding projections, the stem, or tail, w...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/j.jsb.2006.02.012
更新日期：2006-10-01 00:00:00
abstract：:The ultrastructure of β-chitin microfibrils from a centric diatom, Thalassiosira, and a tubeworm, Lamellibrachia, was studied using electron diffraction and high-resolution electron microscopy. Electron microdiffraction diagrams corresponding to each projection of the β-chitin crystals were obtained, and all the data ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.07.001
更新日期：2011-10-01 00:00:00
abstract：:When biological macromolecules are imaged in the transmission electron microscope (TEM), their inherent handedness is lost because the three-dimensional (3D) structure is projected onto a two-dimensional (2D) plane, and identical 2D projections can be made from either 3D enantiomer. Nevertheless, tilt experiments in t...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3896
更新日期：1997-10-01 00:00:00
abstract：:The structure of full-length human TLR5 determined by electron microscopy single-particle image reconstruction at 26Å resolution shows that TLR5 forms an asymmetric homodimer via ectodomain interactions. The structure shows that like TLR9, TLR5 dimerizes in the absence of ligand. The asymmetry of the dimer suggests th...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.12.002
更新日期：2012-02-01 00:00:00
abstract：:Recent studies reveal that mitochondria take substantial responsibility in cellular functions that are closely related to aging diseases caused by degeneration of neurons. These studies emphasize that the membrane and crista morphology of a mitochondrion should receive attention in order to investigate the link betwee...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.03.002
更新日期：2016-06-01 00:00:00
abstract：:Skeletal elements that are exposed to heavy mechanical loads may provide important insights into the evolutionary solutions to mechanical challenges. We analyzed the microscopic architecture of dactylus claws in the woodlice Porcellio scaber and correlated these observations with analyses of the claws' mineral composi...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.06.008
更新日期：2016-08-01 00:00:00
