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Pesquisa : E01.370.350.515.402.150 [Categoria DeCS]
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[PMID]:29382836
[Au] Autor:Füzik T; Formanová P; Ruzek D; Yoshii K; Niedrig M; Plevka P
[Ad] Endereço:Structural Virology, Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500, Brno, Czech Republic.
[Ti] Título:Structure of tick-borne encephalitis virus and its neutralization by a monoclonal antibody.
[So] Source:Nat Commun;9(1):436, 2018 01 30.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Tick-borne encephalitis virus (TBEV) causes 13,000 cases of human meningitis and encephalitis annually. However, the structure of the TBEV virion and its interactions with antibodies are unknown. Here, we present cryo-EM structures of the native TBEV virion and its complex with Fab fragments of neutralizing antibody 19/1786. Flavivirus genome delivery depends on membrane fusion that is triggered at low pH. The virion structure indicates that the repulsive interactions of histidine side chains, which become protonated at low pH, may contribute to the disruption of heterotetramers of the TBEV envelope and membrane proteins and induce detachment of the envelope protein ectodomains from the virus membrane. The Fab fragments bind to 120 out of the 180 envelope glycoproteins of the TBEV virion. Unlike most of the previously studied flavivirus-neutralizing antibodies, the Fab fragments do not lock the E-proteins in the native-like arrangement, but interfere with the process of virus-induced membrane fusion.
[Mh] Termos MeSH primário: Anticorpos Neutralizantes/química
Anticorpos Antivirais/química
Vírus da Encefalite Transmitidos por Carrapatos/ultraestrutura
Fragmentos Fab das Imunoglobulinas/química
Proteínas Virais/química
Vírion/ultraestrutura
[Mh] Termos MeSH secundário: Anticorpos Neutralizantes/biossíntese
Anticorpos Antivirais/biossíntese
Linhagem Celular Tumoral
Microscopia Crioeletrônica
Vírus da Encefalite Transmitidos por Carrapatos/genética
Vírus da Encefalite Transmitidos por Carrapatos/metabolismo
Expressão Gênica
Seres Humanos
Concentração de Íons de Hidrogênio
Fragmentos Fab das Imunoglobulinas/biossíntese
Fusão de Membrana/genética
Neurônios/patologia
Neurônios/virologia
Domínios Proteicos
Multimerização Proteica
Proteínas Virais/genética
Proteínas Virais/metabolismo
Vírion/genética
Vírion/metabolismo
Internalização do Vírus
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antibodies, Neutralizing); 0 (Antibodies, Viral); 0 (Immunoglobulin Fab Fragments); 0 (Viral Proteins)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180201
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-018-02882-0


  2 / 4856 MEDLINE  
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[PMID]:29311594
[Au] Autor:Nakanishi A; Kishikawa JI; Tamakoshi M; Mitsuoka K; Yokoyama K
[Ad] Endereço:Department of Molecular Biosciences, Kyoto Sangyo University, Motoyama Kamigamo, Kita-ku, Kyoto, 603-8555, Japan.
[Ti] Título:Cryo EM structure of intact rotary H -ATPase/synthase from Thermus thermophilus.
[So] Source:Nat Commun;9(1):89, 2018 01 08.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Proton translocating rotary ATPases couple ATP hydrolysis/synthesis, which occurs in the soluble domain, with proton flow through the membrane domain via a rotation of the common central rotor complex against the surrounding peripheral stator apparatus. Here, we present a large data set of single particle cryo-electron micrograph images of the V/A type H -rotary ATPase from the bacterium Thermus thermophilus, enabling the identification of three rotational states based on the orientation of the rotor subunit. Using masked refinement and classification with signal subtractions, we obtain homogeneous reconstructions for the whole complexes and soluble V domains. These reconstructions are of higher resolution than any EM map of intact rotary ATPase reported previously, providing a detailed molecular basis for how the rotary ATPase maintains structural integrity of the peripheral stator apparatus, and confirming the existence of a clear proton translocation path from both sides of the membrane.
[Mh] Termos MeSH primário: Trifosfato de Adenosina/metabolismo
Proteínas de Bactérias/metabolismo
Thermus thermophilus/enzimologia
ATPases Vacuolares Próton-Translocadoras/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Proteínas de Bactérias/ultraestrutura
Transporte Biológico
Microscopia Crioeletrônica
Hidrólise
Modelos Moleculares
Conformação Proteica
Subunidades Proteicas/química
Subunidades Proteicas/metabolismo
Prótons
Rotação
ATPases Vacuolares Próton-Translocadoras/química
ATPases Vacuolares Próton-Translocadoras/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Protein Subunits); 0 (Protons); 8L70Q75FXE (Adenosine Triphosphate); EC 3.6.1.- (Vacuolar Proton-Translocating ATPases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180110
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02553-6


  3 / 4856 MEDLINE  
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[PMID]:29251806
[Au] Autor:Matthews B
[Ad] Endereço:Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA.
[Ti] Título:Tools for protein science.
[So] Source:Protein Sci;27(1):6-9, 2018 01.
[Is] ISSN:1469-896X
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Proteínas/química
[Mh] Termos MeSH secundário: Animais
Dicroísmo Circular
Microscopia Crioeletrônica
Cristalografia por Raios X
Seres Humanos
Ressonância Magnética Nuclear Biomolecular
Conformação Proteica
Análise de Sequência de Proteína
[Pt] Tipo de publicação:EDITORIAL; INTRODUCTORY JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Proteins)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1002/pro.3351


  4 / 4856 MEDLINE  
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[PMID]:28467302
[Au] Autor:Rickgauer JP; Grigorieff N; Denk W
[Ad] Endereço:Howard Hughes Medical Institute, Ashburn, United States.
[Ti] Título:Single-protein detection in crowded molecular environments in cryo-EM images.
[So] Source:Elife;6, 2017 05 03.
[Is] ISSN:2050-084X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We present an approach to study macromolecular assemblies by detecting component proteins' characteristic high-resolution projection patterns, calculated from their known 3D structures, in single electron cryo-micrographs. Our method detects single apoferritin molecules in vitreous ice with high specificity and determines their orientation and location precisely. Simulations show that high spatial-frequency information and-in the presence of protein background-a whitening filter are essential for optimal detection, in particular for images taken far from focus. Experimentally, we could detect small viral RNA polymerase molecules, distributed randomly among binding locations, inside rotavirus particles. Based on the currently attainable image quality, we estimate a threshold for detection that is 150 kDa in ice and 300 kDa in 100 nm thick samples of dense biological material.
[Mh] Termos MeSH primário: Microscopia Crioeletrônica/métodos
Processamento de Imagem Assistida por Computador/métodos
Imagem Individual de Molécula/métodos
[Mh] Termos MeSH secundário: RNA Replicase/ultraestrutura
Rotavirus/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
EC 2.7.7.48 (RNA Replicase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE


  5 / 4856 MEDLINE  
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[PMID]:29260165
[Au] Autor:Xu Z; Zhao W; Wang Z; Yang Y; Sahai N
[Ad] Endereço:State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China. xuzhijun@njtech.edu.cn.
[Ti] Título:Structure analysis of collagen fibril at atomic-level resolution and its implications for intra-fibrillar transport in bone biomineralization.
[So] Source:Phys Chem Chem Phys;20(3):1513-1523, 2018 Jan 17.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Bone is a hierarchical biocomposite material in which a collagen fibril matrix self-assembled in a three-dimensional (3-D) pseudohexagonal array controls many important processes in mineralization such as providing the pathways by which calcium and phosphate species are delivered and a template for the earliest nucleation sites, determining the spatial distribution of the mineral and the topology for binding of associated non-collagenous proteins. However, the structural characteristics of collagen molecules in the fibril remain unclear at the atomic level. Here we performed the first large-scale molecular dynamics simulations to provide a comprehensive all-atom structural analysis of the entire fibril of Type I collagen including intra-fibrillar water distribution. We found that the ideal fibril structure is preserved in specific sites where the earliest nucleation occurs, but is severely distorted in areas that mineralize later. In detail, the ideal pseudohexagonal structure is well-preserved in the overlap zone (c1, c2 and b bands), in the a bands of the hole zone but is severely distorted at the hole/overlap transition (d and c3 bands). As a result, the expected uniform "channel," formed by connecting holes in adjacent unit cells along the b-axis, and having dimensions of 1.5 nm height along the a-axis and width of 40 nm along the c-axis is not formed. The expected uniform channel of 1.5 nm height is preserved only in the a bands in a narrow sub-channel region only 5.8 nm wide. At the hole/overlap transition, an irregular, tortuous sub-channel of widely varying dimensions (∼1.8-4.0 nm height × âˆ¼3.0 nm width) is formed. The well-defined sub-channel in the a bands along with their preferred orientation of charged amino acid residues could facilitate faster molecular diffusion than the tortuous sub-channels and ionic interactions, thus providing the first nucleation sites. Intra-fibrillar water occupies nano-spaces and shows low density (∼0.7 g cm ), which should promote dehydration of ion species. These results provide the first atomic-level understanding of the structure of the collagen fibril and the properties of the aqueous compartments within the fibril, which offer a physical, chemical and steric explanation for calcium phosphate infiltration paths and for the initiation of mineralization at the a band collagen fibril. The mechanism revealed here for the observed specificity of collagen biomineralization in bone formation ultimately contributes to the biochemical and biomechanical functions of the skeleton.
[Mh] Termos MeSH primário: Osso e Ossos/metabolismo
Calcificação Fisiológica/fisiologia
Colágeno Tipo I/química
[Mh] Termos MeSH secundário: Animais
Fosfatos de Cálcio/química
Fosfatos de Cálcio/metabolismo
Colágeno Tipo I/metabolismo
Microscopia Crioeletrônica
Seres Humanos
Modelos Moleculares
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Calcium Phosphates); 0 (Collagen Type I); 97Z1WI3NDX (calcium phosphate)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171221
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp05261h


  6 / 4856 MEDLINE  
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[PMID]:29217583
[Au] Autor:Yin Y; Wu M; Zubcevic L; Borschel WF; Lander GC; Lee SY
[Ad] Endereço:Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA.
[Ti] Título:Structure of the cold- and menthol-sensing ion channel TRPM8.
[So] Source:Science;359(6372):237-241, 2018 01 12.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Transient receptor potential melastatin (TRPM) cation channels are polymodal sensors that are involved in a variety of physiological processes. Within the TRPM family, member 8 (TRPM8) is the primary cold and menthol sensor in humans. We determined the cryo-electron microscopy structure of the full-length TRPM8 from the collared flycatcher at an overall resolution of ~4.1 ångstroms. Our TRPM8 structure reveals a three-layered architecture. The amino-terminal domain with a fold distinct among known TRP structures, together with the carboxyl-terminal region, forms a large two-layered cytosolic ring that extensively interacts with the transmembrane channel layer. The structure suggests that the menthol-binding site is located within the voltage-sensor-like domain and thus provides a structural glimpse of the design principle of the molecular transducer for cold and menthol sensation.
[Mh] Termos MeSH primário: Proteínas Aviárias/química
Mentol/metabolismo
Passeriformes/metabolismo
Canais de Cátion TRPM/química
[Mh] Termos MeSH secundário: Animais
Proteínas Aviárias/metabolismo
Proteínas Aviárias/ultraestrutura
Sítios de Ligação
Temperatura Baixa
Microscopia Crioeletrônica
Processamento de Imagem Assistida por Computador
Modelos Moleculares
Domínios Proteicos
Dobramento de Proteína
Estrutura Secundária de Proteína
Subunidades Proteicas
Canais de Cátion TRPM/metabolismo
Canais de Cátion TRPM/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Avian Proteins); 0 (Protein Subunits); 0 (TRPM Cation Channels); 1490-04-6 (Menthol)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171209
[St] Status:MEDLINE
[do] DOI:10.1126/science.aan4325


  7 / 4856 MEDLINE  
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[PMID]:28745755
[Au] Autor:Isabettini S; Massabni S; Hodzic A; Durovic D; Kohlbrecher J; Ishikawa T; Fischer P; Windhab EJ; Walde P; Kuster S
[Ad] Endereço:Laboratory of Food Process Engineering, ETH Zürich, Schmelzbergstrasse 7, 8092 Zürich, Switzerland. stephane.isabettini@hest.ethz.ch.
[Ti] Título:Molecular engineering of lanthanide ion chelating phospholipids generating assemblies with a switched magnetic susceptibility.
[So] Source:Phys Chem Chem Phys;19(31):20991-21002, 2017 Aug 09.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Lanthanide ion (Ln ) chelating amphiphiles are powerful molecules for tailoring the magnetic response of polymolecular assemblies. Mixtures of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dimyristoyl-sn-glycero-3-phospho-ethanolamine-diethylene triaminepentaacetate (DMPE-DTPA) complexed to Ln deliver highly magnetically responsive bicelles. Their magnetic properties are readily tuned by changing the bicellar size or the magnetic susceptibility Δχ of the bilayer lipids. The former technique is intrinsically bound to the region of the phase diagram guarantying the formation of bicelles. Methods aiming towards manipulating the Δχ of the bilayer are comparatively more robust, flexible and lacking. Herein, we synthesized a new Ln chelating phospholipid using glutamic acid as a backbone: DMPE-Glu-DTPA. The chelate polyhedron was specifically engineered to alter the Δχ, whilst remaining geometrically similar to DMPE-DTPA. Planar asymmetric assemblies hundreds of nanometers in size were achieved presenting unprecedented magnetic alignments. The DMPE-Glu-DTPA/Ln complex switched the Δχ, achieving perpendicular alignment of assemblies containing Dy and parallel alignment of those containing Tm . Moreover, samples with chelated Yb were more alignable than the Tm chelating counterparts. Such a possibility has never been demonstrated for planar Ln chelating polymolecular assemblies. The physico-chemical properties of these novel assemblies were further studied by monitoring the alignment behavior at different temperatures and by including 16 mol% of cholesterol (Chol-OH) in the phospholipid bilayer. The DMPE-Glu-DTPA/Ln complex and the resulting assemblies are promising candidates for applications in numerous fields including pharmaceutical technologies, structural characterization of membrane biomolecules by NMR spectroscopy, as contrasting agents for magnetic resonance imaging, and for the development of smart optical gels.
[Mh] Termos MeSH primário: Elementos da Série dos Lantanídeos/química
Fosfolipídeos/química
[Mh] Termos MeSH secundário: Colesterol/química
Microscopia Crioeletrônica
Dimiristoilfosfatidilcolina/química
Difusão Dinâmica da Luz
Ácido Glutâmico/química
Bicamadas Lipídicas/química
Espectroscopia de Ressonância Magnética
Magnetismo
Difração de Nêutrons
Ácido Pentético/química
Fosfatidiletanolaminas/química
Espalhamento a Baixo Ângulo
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lanthanoid Series Elements); 0 (Lipid Bilayers); 0 (Phosphatidylethanolamines); 0 (Phospholipids); 3KX376GY7L (Glutamic Acid); 7A314HQM0I (Pentetic Acid); 97C5T2UQ7J (Cholesterol); U86ZGC74V5 (Dimyristoylphosphatidylcholine); Z37OX1ASNK (1,2-dimyristoylphosphatidylethanolamine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp03994h


  8 / 4856 MEDLINE  
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[PMID]:29217581
[Au] Autor:Autzen HE; Myasnikov AG; Campbell MG; Asarnow D; Julius D; Cheng Y
[Ad] Endereço:Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94143, USA.
[Ti] Título:Structure of the human TRPM4 ion channel in a lipid nanodisc.
[So] Source:Science;359(6372):228-232, 2018 01 12.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Transient receptor potential (TRP) melastatin 4 (TRPM4) is a widely expressed cation channel associated with a variety of cardiovascular disorders. TRPM4 is activated by increased intracellular calcium in a voltage-dependent manner but, unlike many other TRP channels, is permeable to monovalent cations only. Here we present two structures of full-length human TRPM4 embedded in lipid nanodiscs at ~3-angstrom resolution, as determined by single-particle cryo-electron microscopy. These structures, with and without calcium bound, reveal a general architecture for this major subfamily of TRP channels and a well-defined calcium-binding site within the intracellular side of the S1-S4 domain. The structures correspond to two distinct closed states. Calcium binding induces conformational changes that likely prime the channel for voltage-dependent opening.
[Mh] Termos MeSH primário: Canais de Cátion TRPM/química
[Mh] Termos MeSH secundário: Sítios de Ligação
Cálcio/química
Cálcio/metabolismo
Microscopia Crioeletrônica
Seres Humanos
Interações Hidrofóbicas e Hidrofílicas
Lipídeos
Modelos Moleculares
Nanoestruturas
Conformação Proteica
Domínios Proteicos
Estrutura Secundária de Proteína
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Proteínas Recombinantes/ultraestrutura
Canais de Cátion TRPM/metabolismo
Canais de Cátion TRPM/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Lipids); 0 (Recombinant Proteins); 0 (TRPM Cation Channels); 0 (TRPM4 protein, human); SY7Q814VUP (Calcium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180207
[Lr] Data última revisão:
180207
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171209
[St] Status:MEDLINE
[do] DOI:10.1126/science.aar4510


  9 / 4856 MEDLINE  
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[PMID]:29300742
[Au] Autor:Oliveira LM; Ye Z; Katz A; Alimova A; Wei H; Herman GT; Gottlieb P
[Ad] Endereço:Department of Computer Science, Graduate Center of the City University of New York, New York, NY, United States of America.
[Ti] Título:Component tree analysis of cystovirus φ6 nucleocapsid Cryo-EM single particle reconstructions.
[So] Source:PLoS One;13(1):e0188858, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The 3-dimensional structure of the nucleocapsid (NC) of bacteriophage φ6 is described utilizing component tree analysis, a topological and geometric image descriptor. The component trees are derived from density maps of cryo-electron microscopy single particle reconstructions. Analysis determines position and occupancy of structure elements responsible for RNA packaging and transcription. Occupancy of the hexameric nucleotide triphosphorylase (P4) and RNA polymerase (P2) are found to be essentially complete in the NC. The P8 protein lattice likely fixes P4 and P2 in place during maturation. We propose that the viral procapsid (PC) is a dynamic structural intermediate where the P4 and P2 can attach and detach until held in place in mature NCs. During packaging, the PC expands to accommodate the RNA, and P2 translates from its original site near the inner 3-fold axis (20 sites) to the inner 5-fold axis (12 sites) with excess P2 positioned inside the central region of the NC.
[Mh] Termos MeSH primário: Microscopia Crioeletrônica/métodos
Cystoviridae/ultraestrutura
Nucleocapsídeo/ultraestrutura
Proteínas Virais/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Viral Proteins)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180105
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0188858


  10 / 4856 MEDLINE  
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[PMID]:28465423
[Au] Autor:Wagstaff JM; Tsim M; Oliva MA; García-Sanchez A; Kureisaite-Ciziene D; Andreu JM; Löwe J
[Ad] Endereço:MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.
[Ti] Título:A Polymerization-Associated Structural Switch in FtsZ That Enables Treadmilling of Model Filaments.
[So] Source:MBio;8(3), 2017 May 02.
[Is] ISSN:2150-7511
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial cell division in many organisms involves a constricting cytokinetic ring that is orchestrated by the tubulin-like protein FtsZ. FtsZ forms dynamic filaments close to the membrane at the site of division that have recently been shown to treadmill around the division ring, guiding septal wall synthesis. Here, using X-ray crystallography of FtsZ (SaFtsZ), we reveal how an FtsZ can adopt two functionally distinct conformations, open and closed. The open form is found in SaFtsZ filaments formed in crystals and also in soluble filaments of FtsZ as deduced by electron cryomicroscopy. The closed form is found within several crystal forms of two nonpolymerizing SaFtsZ mutants and corresponds to many previous FtsZ structures from other organisms. We argue that FtsZ's conformational switch is polymerization-associated, driven by the formation of the longitudinal intersubunit interfaces along the filament. We show that such a switch provides explanations for both how treadmilling may occur within a single-stranded filament and why filament assembly is cooperative. The FtsZ protein is a key molecule during bacterial cell division. FtsZ forms filaments that organize cell membrane constriction, as well as remodeling of the cell wall, to divide cells. FtsZ functions through nucleotide-driven filament dynamics that are poorly understood at the molecular level. In particular, mechanisms for cooperative assembly (nonlinear dependency on concentration) and treadmilling (preferential growth at one filament end and loss at the other) have remained elusive. Here, we show that most likely all FtsZ proteins have two distinct conformations, a "closed" form in monomeric FtsZ and an "open" form in filaments. The conformational switch that occurs upon polymerization explains cooperativity and, in concert with polymerization-dependent nucleotide hydrolysis, efficient treadmilling of FtsZ polymers.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Proteínas de Bactérias/metabolismo
Proteínas do Citoesqueleto/química
Proteínas do Citoesqueleto/metabolismo
Citoesqueleto/metabolismo
Staphylococcus aureus/metabolismo
[Mh] Termos MeSH secundário: Divisão Celular
Microscopia Crioeletrônica
Cristalografia por Raios X
Citoesqueleto/química
Escherichia coli/metabolismo
Mutação
Polimerização
Conformação Proteica
Staphylococcus aureus/química
Staphylococcus aureus/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Cytoskeletal Proteins); 0 (FtsZ protein, Bacteria)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180126
[Lr] Data última revisão:
180126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE



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