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[PMID]:29378242
[Au] Autor:Wang X; Xue M; Zhao M; He F; Li C; Li X
[Ad] Endereço:Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China; Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China.
[Ti] Título:Identification of a novel mutation (Ala66Thr) of SRY gene causes XY pure gonadal dysgenesis by affecting DNA binding activity and nuclear import.
[So] Source:Gene;651:143-151, 2018 Apr 20.
[Is] ISSN:1879-0038
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Sex-determining region of the Y chromosome (SRY) gene plays a crucial role in male sexual differentiation and development. Several mutations in the SRY gene have been reported in the high mobility group (HMG) box domain and can cause gonadal dysgenesis symptoms. In this study, we report that a novel missense mutation in the SRY gene, a G to A transition within the HMG box, causes the Ala66Thr amino acid substitution in a female patient presenting 46,XY karyotype with pure gonadal dysgenesis. The G to A base transition was not found in the SRY sequence after the screening of 100 normal males. Furthermore, Ala66Thr mutation drastically reduced the binding capacity of SRY to DNA sequences, whereas wild-type SRY protein showed the normal binding capacity to DNA sequences in vitro. We also found that the mutant SRY protein was partly localized in cytoplasm, whereas wild-type SRY protein was strictly localized in cell nucleus. In addition, we analyzed the three-dimensional structure of SRY protein by homology modeling methods. In conclusion, we identified a novel SRY mutation in a 46,XY female patient with pure gonadal dysgenesis, demonstrating the importance of the Ala66Thr mutation in DNA binding activity and nuclear transport.
[Mh] Termos MeSH primário: Disgenesia Gonadal 46 XY/genética
Mutação de Sentido Incorreto
Proteína da Região Y Determinante do Sexo/genética
[Mh] Termos MeSH secundário: Transporte Ativo do Núcleo Celular
Adolescente
Adulto
Alanina
DNA/metabolismo
Feminino
Células HEK293
Seres Humanos
Cariotipagem
Masculino
Ligação Proteica
Conformação Proteica
Análise de Sequência de DNA
Proteína da Região Y Determinante do Sexo/química
Proteína da Região Y Determinante do Sexo/metabolismo
Treonina
Adulto Jovem
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Sex-Determining Region Y Protein); 2ZD004190S (Threonine); 9007-49-2 (DNA); OF5P57N2ZX (Alanine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180130
[St] Status:MEDLINE


  2 / 154504 MEDLINE  
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[PMID]:29355528
[Au] Autor:Zhu J; Li S; Ramelot TA; Kennedy MA; Liu M; Yang Y
[Ad] Endereço:State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China.
[Ti] Título:Structural insights into the impact of two holoprosencephaly-related mutations on human TGIF1 homeodomain.
[So] Source:Biochem Biophys Res Commun;496(2):575-581, 2018 02 05.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Human protein TGIF1 is an essential regulator of cell fate with broad roles in different tissues, and has been implicated in holoprosencephaly (HPE) and many cancers. The function of TGIF1 in transcriptional regulation depends on its three-amino acid loop extension (TALE) type of homeodomain (HD). Two missense mutations that led to P192A and R219C substitutions in TGIF1-HD were previously found in HPE patients and suggested to be the causes for these cases. However, how these mutations affected TGIF1 function has not been investigated from a structural view. Here, we investigated the roles of P192 and R219 in TGIF1-HD structure packing through determining the NMR structure of TGIF1-HD. Surprisingly, P192 and R219 were found to play roles in packing α1 and α2 to α3 together with A190 and F215 through side-chain interactions. Circular dichroism (CD) showed that P192A and R219C mutants displayed structural change and less folding compared with wild-type TGIF1-HD, and H- N HSQC spectrum of P192A mutant exhibited chemical shift perturbations in all three helices of TGIF1-HD. Thus, it is suggested that P192A and R219C mutations led to structure disturbances of TGIF1-HD, which subsequently reduced the DNA-binding affinity of TGIF1-HD by 23-fold and 10-fold respectively, as revealed by the isothermal titration calorimetry (ITC) experiments. Our study provides structural insights of the probable pathogenesis mechanism of two TGIF1-related HPE cases, and evidences for the roles of P192 and R219 in HD folding.
[Mh] Termos MeSH primário: Holoprosencefalia/genética
Proteínas de Homeodomínio/química
Proteínas de Homeodomínio/genética
Mutação Puntual
Proteínas Repressoras/química
Proteínas Repressoras/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
DNA/metabolismo
Holoprosencefalia/metabolismo
Proteínas de Homeodomínio/metabolismo
Seres Humanos
Modelos Moleculares
Mutação de Sentido Incorreto
Ressonância Magnética Nuclear Biomolecular
Conformação Proteica
Dobramento de Proteína
Proteínas Repressoras/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Homeodomain Proteins); 0 (Repressor Proteins); 0 (TGIF1 protein, human); 9007-49-2 (DNA)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180123
[St] Status:MEDLINE


  3 / 154504 MEDLINE  
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[PMID]:29288668
[Au] Autor:Groves MR; Schroer CFE; Middleton AJ; Lunev S; Danda N; Ali AM; Marrink SJ; Williams C
[Ad] Endereço:Department of Drug Design, Groningen Research Institute of Pharmacy, University of Groningen, 9713AV, The Netherlands.
[Ti] Título:Structural insights into K48-linked ubiquitin chain formation by the Pex4p-Pex22p complex.
[So] Source:Biochem Biophys Res Commun;496(2):562-567, 2018 02 05.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pex4p is a peroxisomal E2 involved in ubiquitinating the conserved cysteine residue of the cycling receptor protein Pex5p. Previously, we demonstrated that Pex4p from the yeast Saccharomyces cerevisiae binds directly to the peroxisomal membrane protein Pex22p and that this interaction is vital for receptor ubiquitination. In addition, Pex22p binding allows Pex4p to specifically produce lysine 48 linked ubiquitin chains in vitro through an unknown mechanism. This activity is likely to play a role in targeting peroxisomal proteins for proteasomal degradation. Here we present the crystal structures of Pex4p alone and in complex with Pex22p from the yeast Hansenula polymorpha. Comparison of the two structures demonstrates significant differences to the active site of Pex4p upon Pex22p binding while molecular dynamics simulations suggest that Pex22p binding facilitates active site remodelling of Pex4p through an allosteric mechanism. Taken together, our data provide insights into how Pex22p binding allows Pex4p to build K48-linked Ub chains.
[Mh] Termos MeSH primário: Proteínas Fúngicas/metabolismo
Peroxinas/metabolismo
Pichia/metabolismo
[Mh] Termos MeSH secundário: Domínio Catalítico
Cristalografia por Raios X
Proteínas Fúngicas/química
Modelos Moleculares
Peroxinas/química
Pichia/química
Ligação Proteica
Conformação Proteica
Ubiquitinação
Ubiquitinas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Fungal Proteins); 0 (Peroxins); 0 (Ubiquitins)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171231
[St] Status:MEDLINE


  4 / 154504 MEDLINE  
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[PMID]:28463568
[Au] Autor:Salinas G; Gao W; Wang Y; Bonilla M; Yu L; Novikov A; Virginio VG; Ferreira HB; Vieites M; Gladyshev VN; Gambino D; Dai S
[Ad] Endereço:1 Worm Biology Lab, Institut Pasteur de Montevideo , Montevideo, Uruguay .
[Ti] Título:The Enzymatic and Structural Basis for Inhibition of Echinococcus granulosus Thioredoxin Glutathione Reductase by Gold(I).
[So] Source:Antioxid Redox Signal;27(18):1491-1504, 2017 Dec 20.
[Is] ISSN:1557-7716
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:AIMS: New drugs are needed to treat flatworm infections that cause severe human diseases such as schistosomiasis. The unique flatworm enzyme thioredoxin glutathione reductase (TGR), structurally different from the human enzyme, is a key drug target. Structural studies of the flatworm Echinococcus granulosus TGR, free and complexed with Au -MPO, a novel gold inhibitor, together with inhibition assays were performed. RESULTS: Au -MPO is a potent TGR inhibitor that achieves 75% inhibition at a 1:1 TGR:Au ratio and efficiently kills E. granulosus in vitro. The structures revealed salient insights: (i) unique monomer-monomer interactions, (ii) distinct binding sites for thioredoxin and the glutaredoxin (Grx) domain, (iii) a single glutathione disulfide reduction site in the Grx domain, (iv) rotation of the Grx domain toward the Sec-containing redox active site, and (v) a single gold atom bound to Cys and Cys in the Au -TGR complex. Structural modeling suggests that these residues are involved in the stabilization of the Sec-containing C-terminus. Consistently, Cys→Ser mutations in these residues decreased TGR activities. Mass spectroscopy confirmed these cysteines are the primary binding site. INNOVATION: The identification of a primary site for gold binding and the structural model provide a basis for gold compound optimization through scaffold adjustments. CONCLUSIONS: The structural study revealed that TGR functions are achieved not only through a mobile Sec-containing redox center but also by rotation of the Grx domain and distinct binding sites for Grx domain and thioredoxin. The conserved Cys and Cys residues targeted by gold assist catalysis through stabilization of the Sec-containing redox center. Antioxid. Redox Signal. 27, 1491-1504.
[Mh] Termos MeSH primário: Echinococcus granulosus/enzimologia
Complexos Multienzimáticos/química
Complexos Multienzimáticos/metabolismo
NADH NADPH Oxirredutases/química
NADH NADPH Oxirredutases/metabolismo
Compostos Organoáuricos/farmacologia
[Mh] Termos MeSH secundário: Animais
Sítios de Ligação/efeitos dos fármacos
Cisteína/metabolismo
Echinococcus granulosus/química
Echinococcus granulosus/genética
Inibidores Enzimáticos/química
Inibidores Enzimáticos/farmacocinética
Glutarredoxinas/metabolismo
Proteínas de Helminto/química
Proteínas de Helminto/genética
Proteínas de Helminto/metabolismo
Modelos Moleculares
Complexos Multienzimáticos/genética
Mutação
NADH NADPH Oxirredutases/genética
Compostos Organoáuricos/química
Ligação Proteica
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzyme Inhibitors); 0 (Glutaredoxins); 0 (Helminth Proteins); 0 (Multienzyme Complexes); 0 (Organogold Compounds); EC 1.6.- (NADH, NADPH Oxidoreductases); EC 1.6.4.- (thioredoxin glutathione reductase); K848JZ4886 (Cysteine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE
[do] DOI:10.1089/ars.2016.6816


  5 / 154504 MEDLINE  
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[PMID]:28455256
[Au] Autor:Kim JH; Cho CW; Kim HY; Kim KT; Choi GS; Kim HH; Cho IS; Kwon SJ; Choi SK; Yoon JY; Yang SY; Kang JS; Kim YH
[Ad] Endereço:College of Pharmacy, Chungnam National University, Daejeon 34134, Republic of Korea; Department of Horticultural and Crop Environment, National Institute of Horticultural and Herbal Science, RDA, Wanju, 55365, Republic of Korea; Advanced Radiation Technology Institute, Korea Atomic Energy Research I
[Ti] Título:α-Glucosidase inhibition by prenylated and lavandulyl compounds from Sophora flavescens roots and in silico analysis.
[So] Source:Int J Biol Macromol;102:960-969, 2017 Sep.
[Is] ISSN:1879-0003
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The enzyme α-glucosidase is a good drug target for the treatment of diabetes mellitus. Four minor flavonoids (1-4) from roots of Sophora flavescens showed the inhibitory activity, with IC values ranging from 11.0±0.3 to 50.6±1.3µM, toward α-glucosidase. An enzyme kinetics analysis of them revealed that the compounds 1 and 4 were non-competitive, and compounds 2 and 3 were un-competitive inhibitors. For molecular docking, 3-dimensional structure of α-glucosidase was built by homology modeling. As the result, four compounds 1-4 were confirmed to interact into common binding site of α-glucosidase. In addition, all of the four prenylated and lavandulyl compounds (1-4) were abundant in an ethyl acetate fraction separated from a methanol extract, and the potential inhibitor (3) was extracted best using tetrahydrofuran.
[Mh] Termos MeSH primário: Simulação por Computador
Extratos Vegetais/farmacologia
Raízes de Plantas/química
Prenilação
Sophora/química
Terpenos/química
alfa-Glucosidases/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Inibidores de Glicosídeo Hidrolases/química
Inibidores de Glicosídeo Hidrolases/metabolismo
Inibidores de Glicosídeo Hidrolases/farmacologia
Simulação de Acoplamento Molecular
Extratos Vegetais/química
Extratos Vegetais/metabolismo
Conformação Proteica
alfa-Glucosidases/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glycoside Hydrolase Inhibitors); 0 (Plant Extracts); 0 (Terpenes); EC 3.2.1.20 (alpha-Glucosidases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170430
[St] Status:MEDLINE


  6 / 154504 MEDLINE  
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[PMID]:29402931
[Au] Autor:Bianchi F; Syga L; Moiset G; Spakman D; Schavemaker PE; Punter CM; Seinen AB; van Oijen AM; Robinson A; Poolman B
[Ad] Endereço:Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9700AB, Groningen, The Netherlands.
[Ti] Título:Steric exclusion and protein conformation determine the localization of plasma membrane transporters.
[So] Source:Nat Commun;9(1):501, 2018 02 05.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The plasma membrane (PM) of Saccharomyces cerevisiae contains membrane compartments, MCC/eisosomes and MCPs, named after the protein residents Can1 and Pma1, respectively. Using high-resolution fluorescence microscopy techniques we show that Can1 and the homologous transporter Lyp1 are able to diffuse into the MCC/eisosomes, where a limited number of proteins are conditionally trapped at the (outer) edge of the compartment. Upon addition of substrate, the immobilized proteins diffuse away from the MCC/eisosomes, presumably after taking a different conformation in the substrate-bound state. Our data indicate that the mobile fraction of all integral plasma membrane proteins tested shows extremely slow Brownian diffusion through most of the PM. We also show that proteins with large cytoplasmic domains, such as Pma1 and synthetic chimera of Can1 and Lyp1, are excluded from the MCC/eisosomes. We hypothesize that the distinct localization patterns found for these integral membrane proteins in S. cerevisiae arises from a combination of slow lateral diffusion, steric exclusion, and conditional trapping in membrane compartments.
[Mh] Termos MeSH primário: Sistemas de Transporte de Aminoácidos Básicos/química
Membrana Celular/metabolismo
ATPases Translocadoras de Prótons/química
Proteínas de Saccharomyces cerevisiae/química
Saccharomyces cerevisiae/metabolismo
[Mh] Termos MeSH secundário: Sistemas de Transporte de Aminoácidos Básicos/metabolismo
Membrana Celular/ultraestrutura
Difusão
Recuperação de Fluorescência Após Fotodegradação
Cinética
Microdomínios da Membrana
Conformação Proteica
Transporte Proteico
ATPases Translocadoras de Prótons/metabolismo
Saccharomyces cerevisiae/ultraestrutura
Proteínas de Saccharomyces cerevisiae/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Amino Acid Transport Systems, Basic); 0 (CAN1 protein, S cerevisiae); 0 (LYP1 protein, S cerevisiae); 0 (Saccharomyces cerevisiae Proteins); EC 3.6.1.- (PMA1 protein, S cerevisiae); EC 3.6.3.14 (Proton-Translocating ATPases)
[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:180207
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-018-02864-2


  7 / 154504 MEDLINE  
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[PMID]:29244007
[Au] Autor:Haspel N; Luo D; González E
[Ad] Endereço:Department of Computer Science, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, 02125, MA, USA. nurit.haspel@umb.edu.
[Ti] Título:Detecting intermediate protein conformations using algebraic topology.
[So] Source:BMC Bioinformatics;18(Suppl 15):502, 2017 Dec 06.
[Is] ISSN:1471-2105
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Understanding protein structure and dynamics is essential for understanding their function. This is a challenging task due to the high complexity of the conformational landscapes of proteins and their rugged energy levels. In particular, it is important to detect highly populated regions which could correspond to intermediate structures or local minima. RESULTS: We present a hierarchical clustering and algebraic topology based method that detects regions of interest in protein conformational space. The method is based on several techniques. We use coarse grained protein conformational search, efficient robust dimensionality reduction and topological analysis via persistent homology as the main tools. We use two dimensionality reduction methods as well, robust Principal Component Analysis (PCA) and Isomap, to generate a reduced representation of the data while preserving most of the variance in the data. CONCLUSIONS: Our hierarchical clustering method was able to produce compact, well separated clusters for all the tested examples.
[Mh] Termos MeSH primário: Biologia Computacional/métodos
Conformação Proteica
Proteínas
[Mh] Termos MeSH secundário: Análise por Conglomerados
Análise de Componente Principal
Proteínas/química
Proteínas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (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:171216
[St] Status:MEDLINE
[do] DOI:10.1186/s12859-017-1918-z


  8 / 154504 MEDLINE  
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[PMID]:28453681
[Au] Autor:Marks C; Nowak J; Klostermann S; Georges G; Dunbar J; Shi J; Kelm S; Deane CM
[Ad] Endereço:Department of Statistics, University of Oxford, Oxford, UK.
[Ti] Título:Sphinx: merging knowledge-based and ab initio approaches to improve protein loop prediction.
[So] Source:Bioinformatics;33(9):1346-1353, 2017 05 01.
[Is] ISSN:1367-4811
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Motivation: Loops are often vital for protein function, however, their irregular structures make them difficult to model accurately. Current loop modelling algorithms can mostly be divided into two categories: knowledge-based, where databases of fragments are searched to find suitable conformations and ab initio, where conformations are generated computationally. Existing knowledge-based methods only use fragments that are the same length as the target, even though loops of slightly different lengths may adopt similar conformations. Here, we present a novel method, Sphinx, which combines ab initio techniques with the potential extra structural information contained within loops of a different length to improve structure prediction. Results: We show that Sphinx is able to generate high-accuracy predictions and decoy sets enriched with near-native loop conformations, performing better than the ab initio algorithm on which it is based. In addition, it is able to provide predictions for every target, unlike some knowledge-based methods. Sphinx can be used successfully for the difficult problem of antibody H3 prediction, outperforming RosettaAntibody, one of the leading H3-specific ab initio methods, both in accuracy and speed. Availability and Implementation: Sphinx is available at http://opig.stats.ox.ac.uk/webapps/sphinx. Contact: deane@stats.ox.ac.uk. Supplementary information: Supplementary data are available at Bioinformatics online.
[Mh] Termos MeSH primário: Biologia Computacional/métodos
Bases de Conhecimento
Modelos Moleculares
Conformação Proteica
Software
[Mh] Termos MeSH secundário: Algoritmos
Animais
Anticorpos/química
Anticorpos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antibodies)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1093/bioinformatics/btw823


  9 / 154504 MEDLINE  
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[PMID]:29335469
[Au] Autor:Aunkham A; Zahn M; Kesireddy A; Pothula KR; Schulte A; Baslé A; Kleinekathöfer U; Suginta W; van den Berg B
[Ad] Endereço:Biochemistry-Electrochemistry Research Unit, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
[Ti] Título:Structural basis for chitin acquisition by marine Vibrio species.
[So] Source:Nat Commun;9(1):220, 2018 01 15.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chitin, an insoluble polymer of N-acetylglucosamine, is one of the most abundant biopolymers on Earth. By degrading chitin, chitinolytic bacteria such as Vibrio harveyi are critical for chitin recycling and maintenance of carbon and nitrogen cycles in the world's oceans. A decisive step in chitin degradation is the uptake of chito-oligosaccharides by an outer membrane protein channel named chitoporin (ChiP). Here, we report X-ray crystal structures of ChiP from V. harveyi in the presence and absence of chito-oligosaccharides. Structures without bound sugar reveal a trimeric assembly with an unprecedented closing of the transport pore by the N-terminus of a neighboring subunit. Substrate binding ejects the pore plug to open the transport channel. Together with molecular dynamics simulations, electrophysiology and in vitro transport assays our data provide an explanation for the exceptional affinity of ChiP for chito-oligosaccharides and point to an important role of the N-terminal gate in substrate transport.
[Mh] Termos MeSH primário: Carbono/metabolismo
Quitina/metabolismo
Nitrogênio/metabolismo
Vibrio/metabolismo
[Mh] Termos MeSH secundário: Acetilglucosamina/metabolismo
Proteínas da Membrana Bacteriana Externa/química
Proteínas da Membrana Bacteriana Externa/genética
Proteínas da Membrana Bacteriana Externa/metabolismo
Ciclo do Carbono
Cristalografia por Raios X
Modelos Moleculares
Ciclo do Nitrogênio
Oceanos e Mares
Oligossacarídeos/metabolismo
Porinas/química
Porinas/genética
Porinas/metabolismo
Conformação Proteica
Água do Mar/química
Água do Mar/microbiologia
Vibrio/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Oligosaccharides); 0 (Porins); 1398-61-4 (Chitin); 7440-44-0 (Carbon); N762921K75 (Nitrogen); V956696549 (Acetylglucosamine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02523-y


  10 / 154504 MEDLINE  
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[PMID]:29295972
[Au] Autor:Jabs F; Plum M; Laursen NS; Jensen RK; Mølgaard B; Miehe M; Mandolesi M; Rauber MM; Pfützner W; Jakob T; Möbs C; Andersen GR; Spillner E
[Ad] Endereço:Immunological Engineering, Department of Engineering, Aarhus University, 8000, Aarhus, Denmark.
[Ti] Título:Trapping IgE in a closed conformation by mimicking CD23 binding prevents and disrupts FcεRI interaction.
[So] Source:Nat Commun;9(1):7, 2018 01 02.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Anti-IgE therapeutics interfere with the ability of IgE to bind to its receptors on effector cells. Here we report the crystal structure of an anti-IgE single-domain antibody in complex with an IgE Fc fragment, revealing how the antibody inhibits interactions between IgE and the two receptors FcεRI and CD23. The epitope overlaps only slightly with the FcεRI-binding site but significantly with the CD23-binding site. Solution scattering studies of the IgE Fc reveal that antibody binding induces a half-bent conformation in between the well-known bent and extended IgE Fc conformations. The antibody acts as functional homolog of CD23 and induces a closed conformation of IgE Fc incompatible with FcεRI binding. Notably the antibody displaces IgE from both CD23 and FcεRI, and abrogates allergen-mediated basophil activation and facilitated allergen binding. The inhibitory mechanism might facilitate strategies for the future development of anti-IgE therapeutics for treatment of allergic diseases.
[Mh] Termos MeSH primário: Epitopos/química
Imunoglobulina E/química
Receptores de IgE/química
[Mh] Termos MeSH secundário: Anticorpos Anti-Idiotípicos/química
Anticorpos Anti-Idiotípicos/metabolismo
Sítios de Ligação
Cristalografia por Raios X
Epitopos/metabolismo
Seres Humanos
Imunoglobulina E/metabolismo
Fragmentos Fc das Imunoglobulinas/química
Fragmentos Fc das Imunoglobulinas/metabolismo
Modelos Moleculares
Ligação Proteica
Conformação Proteica
Receptores de IgE/metabolismo
Anticorpos de Domínio Único/química
Anticorpos de Domínio Único/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antibodies, Anti-Idiotypic); 0 (Epitopes); 0 (Immunoglobulin Fc Fragments); 0 (Receptors, IgE); 0 (Single-Domain Antibodies); 0 (anti-IgE antibodies); 37341-29-0 (Immunoglobulin E)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180104
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02312-7



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