Abstract：
:A common technique in transmission electron microscopy is the collection of a focal pair, in which the first, close to focus image contains higher resolution information at lower contrast, and the second, far from focus image has high contrast but less reliable high-resolution information. Typically these second micrographs are used for purposes of particle selection, orientation estimate or micrograph evaluation. We introduce a technique for merging the information from both images, including signal to noise ratio weighting, contrast transfer function correction, and optional Weiner filtration. This produces a composite image with reduced contrast transfer function artifacts and optimized contrast. This technique is useful in numerous cases where low-contrast images are produced, such as small particles, proteins solubilized in detergent or projects with high-resolution goals when the first image is taken very close to focus.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Ludtke SJ,Chiu Wdoi
10.1016/j.jsb.2003.10.012keywords:
subject
Has Abstractpub_date
2003-10-01 00:00:00pages
73-8issue
1-2eissn
1047-8477issn
1095-8657pii
S1047847703002259journal_volume
144pub_type
杂志文章abstract：:COVID-19 pandemic, caused by SARS-CoV-2, has drastically affected human health all over the world. After the emergence of the pandemic the major focus of efforts to attenuate the infection has been on repurposing the already approved drugs to treat COVID-19 adopting a fast-track strategy. However, to date a specific r...
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abstract：:Four-helical bundles are the most abundant topological motif among helical folds. Their constituent helices show crossing angles that mainly cluster around +20 degrees (aligned) or -50 degrees (orthogonal). Bundles with all helices aligned are called 'square' and comprise four-helical coiled coils as their structurall...
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abstract：:Vibrio alginolyticus use flagella to swim. A flagellum consists of a filament, hook and basal body. The basal body is made up of a rod and several ring structures. This study investigates the structure of the T ring which is a unique component of the V. alginolyticus sodium ion-driven flagellar basal body. Using Zerni...
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abstract：:Chaperone-proteases are responsible for the processive breakdown of proteins in eukaryotic, archaeal and bacterial cells. They are composed of a cylinder-shaped protease lined on the interior with proteolytic sites and of ATPase rings that bind to the apical sides of the protease to control substrate entry. We present...
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abstract：:In situ hybridization (ISH) is a widely applied technique used for visualizing specific nucleic acid sequences at chromosomal, cytologic, and histologic levels. It sometimes fails, however, to demonstrate precise cell identity, early stages of gene expression and variants of alternative splicing because of its limited...
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abstract：:Overproduction and crystallization of Bacillus stearothermophilus ribosomal protein S7 (BstS7), a primary 16S rRNA binding protein and also a translational repressor protein, have been performed to analyze its three-dimensional structure by X-ray crystallography. Ribosomal protein BstS7 was expressed in the cytoplasmi...
journal_title：Journal of structural biology
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abstract：:Three questions central to understanding the initiation of DNA replication in eukaryotes are: (1) Does DNA synthesis begin at a defined place? (2) What determines replication initiation sites? (3) What regulates an origin to fire only once per cell cycle? A key player in this is the origin recognition complex (ORC), r...
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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
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abstract：:We have previously reported the development of AutoEM, a software package for semi-automated acquisition of data from a transmission electron microscope. In continuing efforts to improve the speed of structure determination of macromolecular assemblies by electron microscopy, we report here on the performance of a new...
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journal_title：Journal of structural biology
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journal_title：Journal of structural biology
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abstract：:Nacre is the iridescent inner lining of many mollusk shells, with a unique lamellar structure at the sub-micron scale, and remarkable resistance to fracture. Despite extensive studies, nacre formation mechanisms remain incompletely understood. Here we present 20-nm, 2°-resolution polarization-dependent imaging contras...
journal_title：Journal of structural biology
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doi：10.1016/j.jsb.2013.10.002
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abstract：:In-cell NMR spectroscopy has gained recent popularity since it provides means to analyze the conformational and functional properties of proteins inside living cells and at atomic resolution. High-resolution in-cell NMR spectroscopy was originally established in bacterial cells and based on a rationale that relies on ...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/j.jsb.2007.04.001
更新日期：2007-05-01 00:00:00
abstract：:We examine the structure of the bone of the pharyngeal jaws of a large fish, the black drum (Pogonias cromis), that uses its tooth-jaw complex to crush hard-shelled bivalve mollusks. During mastication huge compressive forces are concentrated in a tiny zone at the tooth-bone interface. We report on the structure of th...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107530
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abstract：:The secondary layer of organophosphatic-shelled brachiopods consists of stratiform laminae in glycosaminoglycans (GAGs), pervaded by canals with chitinous walls. The laminae are composed of various aggregates of protein-coated granules of apatite, 4-8 nm in size, 10 or so soluble proteins, beta-chitinous meshes and sh...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1999.4117
更新日期：1999-06-30 00:00:00
abstract：:Ferritin, the major iron storage protein, has dual functions; it sequesters redox activity of intracellular iron and facilitates iron turn-over. Here we present high angle annular dark field (HAADF) images from individual hepatic ferritin cores within tissue sections, these images were obtained using spherical aberrat...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2008.12.001
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abstract：:We have used three different electron microscopy approaches to calculate three-dimensional maps of tubulin assemblies decorated with the motor domain of kinesin. The approaches used were: (1) Tilt series reconstruction of negatively stained tubulin sheets. (2) Back-projection reconstruction of microtubules in ice. (3)...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3851
更新日期：1997-03-01 00:00:00
abstract：:We describe here a set of multiresolution visualization and docking procedures that we refer to as the Situs package. The package was developed to provide an efficient and robust method for the fitting of atomic structures into low-resolution data. The current release was optimized specifically for the visualization a...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.2000.4350
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abstract：:Studying nanostructured hierarchical materials such as the biomineralized bone is challenging due to their complex 3D structures that call for high spatial resolution. One route to study such materials is X-ray powder diffraction computed tomography (XRD-CT) that reveals the 3D distribution of crystalline phases and X...
journal_title：Journal of structural biology
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abstract：:The genomic DNA in cells of Escherichia coli is localized in one or two compact, phase-like regions with characteristic shapes. Nucleoids undergo progressive changes in shape and compaction in the presence of drugs such as chloramphenicol or puromycin. Forces which influence nucleoid shape and compaction are reviewed,...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
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abstract：:Crustaceans form clots by the rapid crosslinking of a hemolymph clottable protein (CP) to form long, branched polymers. Clotting limits hemolymph loss from wounds as well as playing a part in the innate immune response. CP is a 420 kDa homodimer with a large quantity of associated lipid, primarily the carotenoid pigme...
journal_title：Journal of structural biology
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doi：10.1016/j.jsb.2005.06.008
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abstract：:Raman spectroscopy was used to determine the mineralogical composition of the calcareous tubes of three species belonging to the family Cirratulidae. In all three cases, the tubes were found to be aragonitic, confirming previous inferences based on EDX and thin section studies, and corroborated by new EDX analyses rev...
journal_title：Journal of structural biology
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abstract：:Polyketides such as the clinically-valuable antibacterial agent mupirocin are constructed by architecturally-sophisticated assembly lines known as trans-acyltransferase polyketide synthases. Organelle-sized megacomplexes composed of several copies of trans-acyltransferase polyketide synthase assembly lines have been o...
journal_title：Journal of structural biology
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abstract：:HIV-1 Rev mediates the nuclear export of unspliced and partially-spliced viral transcripts for the production of progeny genomes and structural proteins. In this process, four (or more) copies of Rev assemble onto a highly-structured 351-nt region in such viral transcripts, the Rev response element (RRE). How this occ...
journal_title：Journal of structural biology
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abstract：:Understanding skeletal aging and predicting fracture risk is increasingly important with a growing elderly population. We hypothesized that when categorized by external bone size, the male femoral diaphysis would show different strength-age trajectories which can be explained by changes in morphology, composition and ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107650
更新日期：2020-12-01 00:00:00
abstract：:Aminoglycoside 4-phosphotransferase-Ia (APH(4)-Ia)/Hygromycin B phosphotransferase (Hph) inactivates the aminoglycoside antibiotic hygromycin B (hygB) via phosphorylation. The crystal structure of the binary complex of APH(4)-Ia with hygB was recently reported. To characterize substrate recognition by the enzyme, we d...
journal_title：Journal of structural biology
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doi：10.1016/j.jsb.2013.05.023
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abstract：:Sialic acid residues found as terminal monosaccharides in various types of glycan chains in cell surface glycoproteins and glycolipids have been identified as important contributors of cell-cell interactions in normal vs. abnormal cellular behavior and are pivotal in diseases such as cancers. In vertebrates, sialic ac...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107628
更新日期：2020-11-01 00:00:00
abstract：:Citropin 1.1 is a basic, highly hydrophobic, 16-amino acid peptide (GLFDVIKKVASVIGGL-NH(2)), displaying wide-spectrum antimicrobial activities. In this paper we describe the synthesis and antimicrobial properties of citropin 1.1 and its 18 analogs constituting mostly truncated fragments of citropin 1.1. Moreover, we e...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2009.07.012
更新日期：2009-11-01 00:00:00
abstract：:Traditional single particle reconstruction methods use either the Fourier or the delta function basis to represent the particle density map. This paper proposes a more flexible algorithm that adaptively chooses the basis based on the data. Because the basis adapts to the data, the reconstruction resolution and signal-...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2012.04.012
更新日期：2012-07-01 00:00:00
