Abstract：
:We consider the problem of estimating an unbiased and reference-free ab initio model for non-symmetric molecules from images generated by single-particle cryo-electron microscopy. The proposed algorithm finds the globally optimal assignment of orientations that simultaneously respects all common lines between all images. The contribution of each common line to the estimated orientations is weighted according to a statistical model for common lines' detection errors. The key property of the proposed algorithm is that it finds the global optimum for the orientations given the common lines. In particular, any local optima in the common lines energy landscape do not affect the proposed algorithm. As a result, it is applicable to thousands of images at once, very robust to noise, completely reference free, and not biased towards any initial model. A byproduct of the algorithm is a set of measures that allow to asses the reliability of the obtained ab initio model. We demonstrate the algorithm using class averages from two experimental data sets, resulting in ab initio models with resolutions of 20Å or better, even from class averages consisting of as few as three raw images per class.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Greenberg I,Shkolnisky Ydoi
10.1016/j.jsb.2017.09.007subject
Has Abstractpub_date
2017-11-01 00:00:00pages
106-117issue
2eissn
1047-8477issn
1095-8657pii
S1047-8477(17)30158-2journal_volume
200pub_type
杂志文章abstract：:Tricorn protease from the archaeon Thermoplasma acidophilum acts "downstream" of the proteasome; in conjunction with its aminopeptidase cofactors it converts peptides generated by the proteasome into free amino acids. The basic functional unit of Tricorn is a homohexamer of the 121-kDa subunit, 20 of which can assembl...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1999.4169
更新日期：1999-12-01 00:00:00
abstract：:The yeast peroxisomal hydrolase Lpx1 belongs to the α/β-hydrolase superfamily. In the absence of Lpx1, yeast peroxisomes show an aberrant vacuolated morphology similar to what is found in peroxisomal disorder patients. Here, we present the crystal structure of Lpx1 determined at a resolution of 1.9 Å. The structure re...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.06.008
更新日期：2011-09-01 00:00:00
abstract：:Chemotactic methyltransferase, CheR catalyse methylation of specific glutamate residues in the cytoplasmic domain of methyl-accepting chemotactic protein receptors (MCPRs). The methylation of MCPRs is essential for the chemical sensing and chemotactic bacterial mobility towards favorable chemicals or away from unfavor...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.08.005
更新日期：2016-12-01 00:00:00
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：:A key to understanding control over mineral formation in mollusk shells is the microenvironment inside the pre-formed 3-dimensional organic matrix framework where mineral forms. Much of what is known about nacre formation is from observations of the mature tissue. Although these studies have elucidated several importa...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2008.01.008
更新日期：2008-05-01 00:00:00
abstract：:The fungal pathogen Cryptococcus neoformans is a causative agent of meningoencephalitis in humans. For its pathogenicity, the inositol polyphosphate biosynthetic pathway plays critical roles. Recently, Ipk1 from C. neoformans (CnIpk1) was identified as an inositol 1,3,4,5,6-pentakisphosphate 2-kinase that catalyzes th...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2017.09.004
更新日期：2017-11-01 00:00:00
abstract：:The purified glucocorticoid receptor (GR) from rat liver has been visualised by electron microscopy. The specimens were prepared by spreading on thin carbon support and negatively stained using uranyl acetate. Two forms of GR, the monomeric and the dimeric forms, were identified based on size, chromatographic distribu...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/1047-8477(91)90030-z
更新日期：1991-08-01 00:00:00
abstract：:By direct immunolabeling we have mapped the distribution of photosystem II (PS II) and cytochrome b6/f on the surfaces of photosynthetic membranes isolated from spinach. Photosynthetic membranes were attached to a support and gently disrupted to expose the occluded outer stacked surface, prior to labeling. Polyclonal ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1993.1029
更新日期：1993-07-01 00:00:00
abstract：:The epithelial cell lining of the respiratory groove of Alma emini, an oligochaete glossoscolecid worm that lives in a hydrogen sulfide (H2S)-rich tropical swamp, was investigated by transmission electron microscopy to determine the underlying structural adaptations which enable the worm to subsist in a highly inimica...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1998.4000
更新日期：1998-01-01 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：:Teeth sustain high loads over a lifetime and yet intact tooth failure is rare. The different structures of the tooth, jaw bone and the intervening soft periodontal ligament enable the tooth to endure repeated loading during mastication. Although mechanical and functional properties of the different components are thor...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.11.019
更新日期：2012-02-01 00:00:00
abstract：:Trypanosoma cruzi chagasin belongs to a recently discovered family of cysteine protease inhibitors found in lower eukaryotes and prokaryotes but not in mammals. Chagasin binds tightly to cruzain, the major lysosomal T. cruzi cysteine protease, involved with infectivity and survival of the parasite in mammalian host ce...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2006.07.017
更新日期：2007-02-01 00:00:00
abstract：:Using a 400-kV cryoelectron microscope, we have obtained tomographic reconstructions of frozen-hydrated sea urchin axonemes with 8-10-nm resolution, as assessed by detection of characteristic components including doublet microtubules, radial spokes, central sheath projections, and outer dynein arms. We did not detect ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/s1047-8477(02)00020-5
更新日期：2002-04-01 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
更新日期：2020-08-01 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
pub_type： 杂志文章
doi：10.1016/j.jsb.2013.05.023
更新日期：2013-07-01 00:00:00
abstract：:Zinc-induced sheets of tubulin are two-dimensional crystalline polymers that constitute an ideal sample for high resolution studies of tubulin by electron crystallography. We show that these 2-dimensional tubulin crystals can be stabilized by taxol against low-temperature depolymerization and degradation with time, ea...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1995.1044
更新日期：1995-09-01 00:00:00
abstract：:The repetitive Gly-X-Y sequence is the telltale sign of triple helical domains in collagens and collagen-like proteins. Most collagen sequences contain sporadic interruptions of this pattern, which may have functional roles in molecular flexibility, assembly or molecular recognition. However, the structural signatures...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2014.03.022
更新日期：2014-06-01 00:00:00
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
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107631
更新日期：2020-12-01 00:00:00
abstract：:The optimal balance of cellular nucleotides and the efficient elimination of non-canonical nucleotides are critical to avoiding erroneous mutation during DNA replication. One such mechanism involves the degradation of excessive or abnormal nucleotides by nucleotide-hydrolyzing enzymes. YpgQ contains the histidine-aspa...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.04.002
更新日期：2016-07-01 00:00:00
abstract：:The recombinant dihydropyrimidinase from Sinorhizobium meliloti CECT4114 (SmelDhp) has been characterised and its crystal structure elucidated at 1.85A. The global architecture of the protein is reminiscent of that of the amidohydrolase superfamily, consisting of two domains; an (alpha/beta)(8) TIM-like barrel domain,...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2009.10.013
更新日期：2010-02-01 00:00:00
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 have used conical tomography to study the structure of integral proteins in their phospholipid bilayer environments. Complete conical series were collected from replicas of the water channel aquaporin-0 (AQP0), a 6.6 nm side tetramer with a molecular weight of approximately 120 kDa that was purified and reconstitut...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2004.09.004
更新日期：2005-01-01 00:00:00
abstract：:The human vertebral body and intervertebral disc interface forms the region where the cartilaginous endplate, annulus fibrosis and bone of the vertebral body are connected through an intermediate calcified cartilage layer. While properties of both the vertebral body and components of the disc have been extensively stu...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2013.08.011
更新日期：2013-11-01 00:00:00
abstract：:Molecular genetic studies with prokaryotic microorganisms reveal that many different molecular processes contribute to the formation of spontaneous mutations. Besides infidelities in DNA replication and the consequences of environmental mutagens, enzyme-mediated DNA rearrangements bring about important, evolutionarily...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/1047-8477(90)90064-j
更新日期：1990-07-01 00:00:00
abstract：:Collagen is the most important structural protein of the animal body. Its unique triple-helix structure and extremely high level of crystallinity make it exceptionally efficient in generating the second harmonic of incident light, and we show here how this leads to a novel mode of microscopy of immediate practical sig...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/s1047-8477(02)00576-2
更新日期：2003-01-01 00:00:00
abstract：:TheL-A virus (LAV) particle is a specialized compartment for the transcription and replication of double-stranded RNA. It is 390 A in diameter and infects yeast. The particle is formed by a capsid containing 120 copies of a 680-residue gene product arranged with T = 1 icosahedral symmetry, approximately two copies of ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.2001.4371
更新日期：2001-07-01 00:00:00
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...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/s1047-8477(03)00124-2
更新日期：2003-08-01 00:00:00
abstract：:A Gatan 1024 x 1024 slow-scan charge-coupled device (CCD) camera has been interfaced to a JEOL4000EX electron cryomicroscope and explored for its usefulness in the electron crystallographic analysis of thin, glucose-embedded crystals of crotoxin complex kept at -125 degrees C. We show that the camera allows for an on-...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1994.1029
更新日期：1994-07-01 00:00:00
abstract：:The 32 kDa hydrophilic and acidic enamelin, the most stable cleavage fragment of the enamel specific glycoprotein, is believed to play vital roles in controlling crystal nucleation or growth during enamel biomineralization. Circular dichroism and Fourier transform infrared spectra demonstrate that the secondary struct...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2008.04.007
更新日期：2008-07-01 00:00:00
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
pub_type： 杂志文章
doi：10.1016/j.jsb.2018.03.011
更新日期：2018-08-01 00:00:00
