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 cells. In the scope of a project to characterize proteins diferentially expressed during T. cruzi metacyclogenesis, we have determined the crystal structure of chagasin, which is now the first X-ray structure of a chagasin-like cysteine protease inhibitor to be reported. The structure was solved by the SIRAS method and refined at 1.7A resolution and a comparison with the two NMR structures available revealed some differences in the loops involved in binding to cysteine proteases. The highly flexible loop 4 could be entirely modeled and residues 29-33 from loop 2 form a 3(10)-helix structure that may be important to stabilize the loop conformation. Chagasin crystal structure was docked to the highest resolution structure available of cruzain and a model of chagasin-cruzain interaction was analyzed. The knowledge of the chagasin crystal structure may contribute to the elucidation of the molecular mechanism involved in the inhibition of cruzain and other T. cruzi cysteine proteases.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Figueiredo da Silva AA,de Carvalho Vieira L,Krieger MA,Goldenberg S,Zanchin NI,Guimarães BGdoi
10.1016/j.jsb.2006.07.017subject
Has Abstractpub_date
2007-02-01 00:00:00pages
416-23issue
2eissn
1047-8477issn
1095-8657pii
S1047-8477(06)00231-0journal_volume
157pub_type
杂志文章abstract::The configuration of the active site of E2 ligases, central enzymes in the ubiquitin/ubiquitin-like protein (Ub/Ubl) conjugation systems, has long puzzled researchers. Taking advantage of the wealth of newly available structures and sequences of E2s from diverse organisms, we performed a large-scale comparative analys...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2007.12.006
更新日期:2008-05-01 00:00:00
abstract::Titin is a giant protein responsible for passive-tension generation in muscle sarcomeres. Here, we used single-molecule AFM force spectroscopy to investigate the mechanical characteristics of a recombinant construct from the human cardiac-specific N2B-region, which harbors a 572-residue unique sequence flanked by two ...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2006.02.017
更新日期:2006-08-01 00:00:00
abstract::Gramicidin is a polypeptide antibiotic which forms dimeric channels specific for the transport of monovalent cations across membranes. It adopts several different conformations, most notably double helical (pore) and helical dimer (channels) forms, which have very different structural and functional characteristics. T...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1006/jsbi.1997.3948
更新日期:1998-01-01 00:00:00
abstract::The mechanisms which cause macromolecules to form discrete compartments within the nucleus are not understood. Here, two ubiquitous compartments, nucleoli, and PML bodies, are shown to disassemble when K562 cell nuclei expand in medium of low monovalent cation concentration; their major proteins dispersed as seen by i...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2003.12.008
更新日期:2004-06-01 00:00:00
abstract::Random spherically constrained (RSC) single particle reconstruction is a method to obtain structures of membrane proteins embedded in lipid vesicles (liposomes). As in all single-particle cryo-EM methods, structure determination is greatly aided by reliable detection of protein "particles" in micrographs. After fittin...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2014.01.004
更新日期:2014-03-01 00:00:00
abstract::Titin is a giant protein that spans half of the striated muscle sarcomere. The I-band portion of titin extends as the sarcomere is stretched, developing what is known as passive force. This portion of the molecule is composed mainly of tandem immunoglobulin (Ig) segments, consisting of serially linked Ig-like domains,...
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
abstract::The emergence of electron tomography as a tool for three dimensional structure determination of cells and tissues has brought its own challenges for the preparation of thick sections. High pressure freezing in combination with freeze substitution provides the best method for obtaining the largest volume of well-preser...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2007.09.002
更新日期:2008-03-01 00:00:00
abstract::The goal of this study is to evaluate the performance of software for automated particle-boxing, and in particular the performance of a new tool (TextonSVM) that recognizes the characteristic texture of particles of interest. As part of a high-throughput protocol, we use human editing that is based solely on class-ave...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2011.05.017
更新日期:2011-09-01 00:00:00
abstract::Beam damage is the main resolution-limiting factor when biological particles are observed by cryoelectron microscopy in a thin vitrified solution film. Furthermore, the low contrast of the specimen frequently makes observation difficult and limits the possibility of image processing. Cryo-negative staining, in which t...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/s1047-8477(02)00035-7
更新日期:2002-06-01 00:00:00
abstract::Since the foundation for the three-dimensional image reconstruction of helical objects from electron micrographs was laid more than 30 years ago, there have been sustained developments in specimen preparation, data acquisition, image analysis, and interpretation of results. However, the boxing of filaments in large nu...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1006/jsbi.2001.4415
更新日期:2001-09-01 00:00:00
abstract::Sequence comparisons have been undertaken for all hair and epithelial keratin IF chains from a single species--human. The results lead to several new proposals. First, it is clear that not only is the chain structure of the molecule an obligate heterodimer but promiscuous association of Type I and Type II chains must ...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2006.12.002
更新日期:2007-06-01 00:00:00
abstract::REMORINs are nanodomain-organized proteins located in the plasma membrane and involved in cellular responses in plants. The dynamic assembly of the membrane nanodomains represents an essential tool of the versatile membrane barriers to control and modulate cellular functions. Nevertheless, the assembly mechanisms and ...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2018.02.003
更新日期:2019-04-01 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
更新日期:1991-06-01 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::This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy. ...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2013.02.005
更新日期:2013-02-18 00:00:00
abstract::DivIVA or Wag31, which is an essential pole organizing protein in mycobacteria, can self-assemble at the negatively curved side of the membrane at the growing pole to form a higher order structural scaffold for maintaining cellular morphology and localizing various target proteins for cell-wall biogenesis. The structu...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2019.107429
更新日期:2020-02-01 00:00:00
abstract::We have cloned and expressed in Escherichia coli cDNA for rat nuclear transport factor 2 (NTF2), a key cytoplasmic factor that facilitates the import of proteins into the nucleus through nuclear pores. We have used this bacterially expressed material to produce orthorhombic crystals suitable for high-resolution X-ray ...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1006/jsbi.1996.0049
更新日期:1996-03-01 00:00:00
abstract::The power of cryo-electron tomography (cryoET) lies in its capability to characterize macromolecules in their cellular context. Structure determination by cryoET, however, is time-consuming compared to single particle approaches. A recent study reported significant acceleration of data acquisition by a fast-incrementa...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2019.08.006
更新日期:2019-11-01 00:00:00
abstract::A structural analysis of cells that contained the interferon-alpha-induced lupus inclusions (LI) was performed using a high-voltage electron microscope to determine the exact cellular location of LI and their association with normal cell organelles. LI were induced in the human B lymphoblastoid cell line, Daudi, by cu...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/1047-8477(92)90004-t
更新日期:1992-01-01 00:00:00
abstract::A simple, fast and efficient noise-reduction protocol for three-dimensional electron tomographic reconstructions of biological material is presented. The approach is based on iterative application of median filtering and shows promise for automatic noise reduction as a pre-processor for automated data analysis tools w...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2006.10.030
更新日期:2007-05-01 00:00:00
abstract::High-resolution light-microscopy and high-throughput screening are two essential methodologies for characterizing cellular phenotypes. Optimally combining these methodologies in cell-based screening to test detailed molecular and cellular responses to multiple perturbations constitutes a major challenge. Here we descr...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2006.12.013
更新日期:2007-05-01 00:00:00
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::Non-collagenous proteins such as osteocalcin function as regulators of the mineralization process in bone. Osteocalcin undergoes post-translational modification adding an extra carboxylate group on three of its glutamate residues to enhance interaction with bone mineral. In this work, we examine regulation of biomimet...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2019.04.014
更新日期:2019-08-01 00:00:00
abstract::Control of tissue composition and organization will be a key feature in the development of successful products through tissue engineering. However, the mechanism of collagen fibril formation, growth, and organization is not yet fully understood. In this study we have examined collagen fibril formation in a wound heali...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1006/jsbi.2002.4460
更新日期:2002-01-01 00:00:00
abstract::The cyclooxygenases (COX-1 and COX-2) catalyze the rate-limiting step in the biosynthesis of prostaglandins, and are the pharmacological targets of non-steroidal anti-inflammatory drugs (NSAIDs) and COX-2 selective inhibitors (coxibs). Ibuprofen (IBP) is one of the most commonly available over-the-counter pharmaceutic...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2014.11.005
更新日期:2015-01-01 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
abstract::Nucleoids isolated from Escherichia coli at low salt concentrations in the presence of spermidine (Kornberg et al., Proc. Natl. Acad. Sci. USA, 71, 3189-3193 (1974)) retain large amounts of protein and RNA and are, thus, potentially useful in structural and other studies. However, these preparations have neither been ...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1006/jsbi.1997.3883
更新日期:1997-08-01 00:00:00
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
pub_type: 杂志文章
doi:10.1016/j.jsb.2015.12.011
更新日期:2016-03-01 00:00:00
abstract::The AAA+ family of proteins play fundamental roles in all three kingdoms of life. It is thought that they act as molecular chaperones in aiding the assembly or disassembly of proteins or protein complexes. Recent structural studies on a number of AAA+ family proteins have revealed that they share similar structural el...
journal_title:Journal of structural biology
pub_type: 杂志文章
doi:10.1016/j.jsb.2003.11.022
更新日期:2004-04-01 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
更新日期:2001-02-01 00:00:00