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 inimical habitat. The epithelium of the respiratory groove is made up of squamous cells with a highly amplified free epithelial surface. The cells are tightly packed with electron dense sulfur metabolizing bodies (SMBs) and contain endosymbiotic bacteria. Presence of sulfur in the electron dense SMBs was confirmed by X-ray microanalysis. Certain eukaryotic cells with prominent filopodia-like cytoplasmic extensions were observed under the epithelial cells and in the muscle tissue. The cells contained numerous heteromorphic endosymbiotic bacteria and scattered SMBs. Both the SMBs and the bacteria are reckoned to be involved in scavenging and detoxifying H2S. The removal of sulfide complexes was observed to occur through excision of blebs formed by epithelial cell membrane elaborations and by exocytosis of crystalline-like particles. These adaptive stratagems generally correspond with those that have been adopted by many marine and hydrothermal vent organisms that occupy sulfide-rich biomes. The congruent adaptive stratagems and ultrastructural morphologies in such a diverse community of organisms have been imposed by a common need to neutralize the insidious effects of H2S in their environments. Copyright 1998 Academic Press.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Maina JN,Maloiy GMOdoi
10.1006/jsbi.1998.4000subject
Has Abstractpub_date
1998-01-01 00:00:00pages
257-66issue
3eissn
1047-8477issn
1095-8657pii
S104784779894000Xjournal_volume
122pub_type
杂志文章abstract：:Human scalp hairs are often examined microscopically to study the variation and diversity among a range of visible morphological traits. In this study, we focused on the ultrastructure of human scalp hair within its keratinized matrix, emphasizing, the density and distribution of melanosomes, variation in cuticle thic...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2018.11.008
更新日期：2019-01-01 00:00:00
abstract：:Microfluidics, or lab-on-a-chip technology, is proving to be a powerful, rapid, and efficient approach to a wide variety of bioanalytical and microscale biopreparative needs. The low materials consumption, combined with the potential for packing a large number of experiments in a few cubic centimeters, makes it an att...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/s1047-8477(03)00049-2
更新日期：2003-04-01 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：: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：:Gap junction proteins, termed connexins, constitute a multigene family of polytopic membrane channel proteins that have four hydrophobic transmembrane domains with the N- and C-termini located on the cytoplasmic membrane face. The principal gap junction protein in the heart, alpha 1 connexin (also designated Cx43), me...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1006/jsbi.1998.3972
更新日期：1998-01-01 00:00:00
abstract：:Chaperonins mediate protein folding in an ATP-dependent manner. ATP binding and hydrolysis by chaperonins are subject to both homotropic and heterotropic allosteric regulation. In the case of GroEL and CCT, homotropic regulation by ATP is manifested in nested cooperativity, which involves positive intra-ring cooperati...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1006/jsbi.2001.4377
更新日期：2001-08-01 00:00:00
abstract：:Poly(A)-binding protein (PABP) is an RNA-binding protein that binds specifically to the poly(A) tail of messenger RNAs in eukaryotes. The PABP/poly(A) tail complex has been implicated as being important in promoting the efficient initiation of translation as well as in maintaining the integrity of the mRNA. PABP binds...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3864
更新日期：1997-07-01 00:00:00
abstract：:Accurate image alignment is needed for computing three-dimensional reconstructions from transmission electron microscope tilt series. So far, the best results have been obtained by using colloidal gold beads as fiducial markers. If their use has not been possible for some reason, the only option has been the automatic...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.2001.4443
更新日期：2001-12-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1998.3984
更新日期：1998-01-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/s1047-8477(03)00039-x
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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：:Staphylococcus aureus hibernation promoting factor (SaHPF) is responsible for the formation of 100S ribosome dimers, which in turn help this pathogen to reduce energy spent under unfavorable conditions. Ribosome dimer formation strongly depends on the dimerization of the C-terminal domain of SaHPF (CTDSaHPF). In this ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2019.107408
更新日期：2020-01-01 00:00:00
abstract：:Three-dimensional crystals were obtained for the membrane domain of the human erythrocyte anion exchanger (AE1, Band 3). Protein homogeneity and stability and the delicate balance between the detergent used and the amount of phospholipids copurifying are critical to the formation of three-dimensional crystals of the A...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/s1047-8477(02)00010-2
更新日期：2002-03-01 00:00:00
abstract：:Hard X-ray fluorescence microscopy and magnified phase contrast imaging are combined to obtain quantitative maps of the projected metal concentration in whole cells. The experiments were performed on freeze dried cells at the nano-imaging station ID22NI of the European Synchrotron Radiation Facility (ESRF). X-ray fluo...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.12.005
更新日期：2012-02-01 00:00:00
abstract：:We analyzed a tertiary structure of systemin, the first identified polypeptide plant hormone, using two-dimensional NMR spectroscopy. From these data and molecular dynamics calculations we concluded that the peptide can adopt a Z-like-beta-sheet structure, which has previously been found in many specific DNA-binding p...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1995.1026
更新日期：1995-07-01 00:00:00
abstract：:The photosynthetic membrane in purple bacteria contains several pigment-protein complexes that assure light capture and establishment of the chemiosmotic gradient. The bioenergetic tasks of the photosynthetic membrane require the strong interaction between these various complexes. In the present work, we acquired the ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2010.08.010
更新日期：2011-01-01 00:00:00
abstract：:Crystalline features of cellulose microfibrils in the cell walls of Glaucocystis (Glaucophyta) were studied by combined spectroscopy and diffraction techniques, and the results were compared with those of Oocystis (Chlorophyta). Although these algae are grouped into two different classes, by the composition of their c...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1999.4160
更新日期：1999-10-01 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：:The nuclear lamina is a protein meshwork that lines the nuclear envelope in metazoan cells. It is composed largely of a polymeric assembly of lamins, which comprise a distinct sequence homology class of the intermediate filament protein family. On the basis of its structural properties, the lamina originally was propo...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/j.jsb.2011.11.007
更新日期：2012-01-01 00:00:00
abstract：:AVS (Application Visualization System) is commercially available software for analyzing and viewing data. AVS is primarily used in the physical sciences and engineering, and here we describe the application of AVS for examining three-dimensional density maps generated by electron microscopy and image processing. For t...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1996.0017
更新日期：1996-01-01 00:00:00
abstract：:DNA-dependent protein kinase (DNA-PK) is part of the eukaryotic DNA double strand break repair pathway and as such is crucial for maintenance of genomic stability, as well as for V(D)J (variable-diversity-joining) recombination. The catalytic subunit of DNA-PK (DNA-PKcs) belongs to the phosphatidylinositol-3 (PI-3) ki...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2003.11.024
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abstract：:The formation of amyloid is considered an intrinsic ability of most polypeptides. It is a structure adopted by many neuropeptides and neurohormones during the formation of dense core vesicles in secretory cells, yet the mechanisms mediating assembly and disassembly of these amyloids remain unclear. Neurokinin B is a n...
journal_title：Journal of structural biology
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doi：10.1016/j.jsb.2019.09.011
更新日期：2019-12-01 00:00:00
abstract：:The massive basal skeleton of a few remnant living hypercalcified sponges rediscovered since the 1960s are valuable representatives of ancient calcium carbonate biomineralization mechanisms in basal Metazoa. A multi-scale mineralogical characterization of the easily accessible Mediterranean living hypercalcified spong...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.08.008
更新日期：2011-12-01 00:00:00
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：:The analysis of structure factors in 3D cryo-EM Coulomb potential maps and their "enhancement" at the end of the reconstruction process is a well-established practice, normally referred to as sharpening. The aim is to increase contrast and, in this way, to help tracing the atomic model. The most common way to accompli...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107447
更新日期：2020-03-01 00:00:00
abstract：:This study demonstrates the effects of progesterone on eggshell quality and ultrastructure by injecting progesterone into laying hens 2 and 5 h post-oviposition, respectively. Progesterone injected 2 h post-oviposition (P4-2 h) improved eggshell quality with a significant decrease (P < 0.01) in the thickness of the ma...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2019.107430
更新日期：2020-02-01 00:00:00
abstract：:The structure determination of macromolecular complexes is entering a new era. The methods of optical microscopy, electron microscopy, X-ray crystallography, and nuclear magnetic resonance increasingly are being combined in hybrid method approaches to achieve an integrated view of macromolecular complexes that span fr...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/j.jsb.2006.10.028
更新日期：2007-05-01 00:00:00
abstract：:The properties and characteristics shared by amyloid fibrils formed from disease and non-disease associated proteins that are unrelated in sequence and structure offer the prospect that model systems can be used to systematically assess the factors that predispose a native protein to form amyloid fibrils. Based on a d...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2006.01.017
更新日期：2006-08-01 00:00:00
abstract：:3,4-dihydroxy 2-butanone 4-phosphate synthase (DHBPS) and GTP cyclohydrolase-II (GTPCH-II) are the two initial enzymes involved in riboflavin biosynthesis pathway, which has been shown to be essential for the pathogens. In Mycobacterium tuberculosis (Mtb), the ribA2 gene (Rv1415) encodes for the bi-functional enzyme w...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.01.013
更新日期：2011-05-01 00:00:00
abstract：:Single-axis cryo-electron tomography of vitrified specimens has become a method of choice to reconstruct in three dimensions macromolecular assemblies in their cellular context or prepared from purified components. Here, we asked how a dual-axis acquisition scheme would improve three-dimensional reconstructions of mic...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2012.11.004
更新日期：2013-02-01 00:00:00
