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 observed by others through transmission electron microscopy to be located at the Bacillus subtilis plasma membrane, where the synthesis and export of the antibacterial polyketide bacillaene takes place. In this work we analyze ten crystal structures of trans-acyltransferase polyketide synthases ketosynthase domains, seven of which are reported here for the first time, to characterize a motif capable of zippering assembly lines into a megacomplex. While each of the three-helix LINKS (Laterally-INteracting Ketosynthase Sequence) motifs is observed to similarly dock with a spatially-reversed copy of itself through hydrophobic and ionic interactions, the amino acid sequences of this motif are not conserved. Such a code is appropriate for mediating homotypic contacts between assembly lines to ensure the ordered self-assembly of a noncovalent, yet tightly-knit, enzymatic network. LINKS-mediated lateral interactions would also have the effect of bolstering the vertical association of the polypeptides that comprise a polyketide synthase assembly line.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Gay DC,Wagner DT,Meinke JL,Zogzas CE,Gay GR,Keatinge-Clay ATdoi
10.1016/j.jsb.2015.12.011subject
Has Abstractpub_date
2016-03-01 00:00:00pages
196-205issue
3eissn
1047-8477issn
1095-8657pii
S1047-8477(15)30117-9journal_volume
193pub_type
杂志文章abstract：:Low complexity regions (LCRs) in protein sequences have special properties that are very different from those of globular proteins. The rules that define secondary structure elements do not apply when the distribution of amino acids becomes biased. While there is a tendency towards structural disorder in LCRs, various...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2019.08.003
更新日期：2019-11-01 00:00:00
abstract：:A comprehensive analysis of the sequences of all types of intermediate filament chains has been undertaken with a particular emphasis on those of segment 1A and linker L1. This has been done to assess whether structural characteristics can be recognized in the sequences that would be consistent with the role of each r...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.2002.4438
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abstract：:Nacre has long served as a model for understanding the biomineralization mechanism and designing bio-inspired materials. However, its basic building blocks, the aragonite tablets, are still under debate in terms of their fine structure at the nanoscale and corresponding formation mechanism. Here, using a field emissio...
journal_title：Journal of structural biology
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doi：10.1016/j.jsb.2013.01.010
更新日期：2013-04-01 00:00:00
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...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2009.07.003
更新日期：2009-11-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
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更新日期：2020-02-01 00:00:00
abstract：:Null-mutation in Drosophila importin-alpha2, such as the deficiency imp-alpha2(D14), causes recessive female sterility with the formation of dumpless eggs. In imp-alpha2(D14) the transfer of nurse cell components to the oocyte is interrupted and the Kelch protein, an oligomeric ring canal actin organizer, is normally ...
journal_title：Journal of structural biology
pub_type： 杂志文章
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更新日期：2006-04-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.06.008
更新日期：2016-08-01 00:00:00
abstract：:Dipeptidase 3 (DPEP3) is one of three glycosylphosphatidylinositol-anchored metallopeptidases potentially involved in the hydrolytic metabolism of dipeptides. While its exact biological function is not clear, DPEP3 expression is normally limited to testis, but can be elevated in ovarian cancer. Antibody drug conjugate...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107512
更新日期：2020-07-01 00:00:00
abstract：:An approach to automated acquisition of cryoEM image data from lacey carbon grids using the Leginon program is described. Automated liquid nitrogen top up of the specimen holder dewar was used as a step towards full automation, without operator intervention during the course of data collection. During cryoEM studies o...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2010.08.014
更新日期：2010-12-01 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：: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：:Computational protein design methods have enabled the design of novel protein structures, but they are often still limited to small proteins and symmetric systems. To expand the size of designable proteins while controlling the overall structure, we developed Elfin, a genetic algorithm for the design of novel proteins...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2017.09.001
更新日期：2018-02-01 00:00:00
abstract：:Centrioles are microtubule-based structures that play essential roles in cell division and cilia biogenesis. Cep120 is an important protein for correct centriole formation and mutations in the Cep120 gene cause severe human diseases like Joubert syndrome and complex ciliopathies. Here, we show that Cep120 contains thr...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2018.01.009
更新日期：2018-07-01 00:00:00
abstract：:The design and selection of peptides targeting cellular proteins is challenging and often yields candidates with undesired properties. Therefore we deployed a new selection system based on the twin-arginine translocase (TAT) pathway of Escherichia coli, named hitchhiker translocation (HiT) selection. A pool of α-helix...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2014.03.002
更新日期：2014-06-01 00:00:00
abstract：:Human coagulation factor VIIai that lacks the Gla domain (residues 1-44) has been prepared, purified, and crystallised. First, recombinant factor VII was activated to form factor VIIa, the active site was then inhibited with 1,5-dansyl-Glu-Gly-Arg-chloromethyl ketone, and finally the Gla domain was removed by chymotry...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1998.4078
更新日期：1999-03-01 00:00:00
abstract：:Cryoelectron microscopy provides the means of studying macromolecules in their native state. However, the contrast transfer function (CTF) makes the images and the three-dimensional (3D) maps derived from them difficult to interpret. We developed methods to determine the CTF from experimental data and to obtain a CTF-...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3845
更新日期：1997-04-01 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
更新日期：2004-03-01 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 exoskeleton of the American lobster Homarus americanus is a hierarchically organized nano-composite material consisting of organic chitin-protein fibers associated with inorganic calcium carbonate. The presence of a well-developed and periodically arranged pore canal system leads to a honeycomb-like structure. The...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2007.09.022
更新日期：2008-02-01 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
abstract：:Cryoelectron microscopy makes it possible to record high-resolution detail from large and complex structures. However, its application to understanding cellular structure is limited by the requirement that samples should be no thicker than approximately 0.5-1 microm. Therefore it is important to develop the ability to...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/s1047-8477(03)00016-9
更新日期：2003-05-01 00:00:00
abstract：:Nonlinear optical processes have found widespread applications in fields ranging from fundamental physics to biomedicine. In this study, we attempted to evaluate cell activation by using the Third Harmonic Generation (THG) imaging microscopy as a new diagnostic tool. The BV-2 microglia cell line with or without activa...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2014.11.011
更新日期：2015-02-01 00:00:00
abstract：:Cryogenic electron microscopy (cryo-EM) and single-particle analysis enables determination of near-atomic resolution structures of biological molecules. However, large computational requirements limit throughput and rapid testing of new image processing tools. We developed PRIME, an algorithm part of the SIMPLE softwa...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2018.08.005
更新日期：2018-11-01 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：:The biomechanical properties of the zone of calcified cartilage (ZCC) in articulating joints are of clinical relevance due to the role ZCC plays in load transfer from cartilage to bone. To determine the micron-level mechanical properties and their correlation to mineral concentration in the ZCC, we combined nanoindent...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2004.10.010
更新日期：2005-02-01 00:00:00
abstract：:Recent advances in cryo-electron tomography (cryo-ET) have allowed direct visualization of the initial interactions between bacteriophages and their hosts. Previous studies focused on phage infection in Gram-negative bacteria but it is of particular interest how phages penetrate the thick, highly cross-linked Gram-pos...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.07.019
更新日期：2017-02-01 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：:We report a detailed work of composition and location of naturally formed iron biominerals in plant cells tissues grown in iron rich environments as Imperata cylindrica. This perennial grass grows on the Tinto River banks (Iberian Pyritic Belt) in an extreme acidic ecosystem (pH∼2.3) with high concentration of dissolv...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2015.11.005
更新日期：2016-01-01 00:00:00
abstract：:We present a sample preparation method for cryo-electron microscopy (cryo-EM) that requires only 3-20nL of sample to prepare a cryo-EM grid, depending on the protocol used. The sample is applied and spread on the grid by a microcapillary. The procedure does not involve any blotting steps, and real-time monitoring allo...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.11.002
更新日期：2017-03-01 00:00:00
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
doi：10.1016/j.jsb.2006.03.022
更新日期：2006-11-01 00:00:00
