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971.
Claudio Dalvit Philipp Floersheim Mauro Zurini Armin Widmer 《Journal of biomolecular NMR》1999,14(1):23-32
Application of a modified ePHOGSY and other novel NMR experiments to an H2O-DMSO solution of the protein FKBP12 identified the presence of one molecule of DMSO bound in the substrate binding site. It occupies the same spatial region occupied by the pipecolidine moiety of the immunosuppressive drugs FK506 and Rapamycin complexed to the protein. The binding constant KD for this DMSO molecule was only 275 mM. A substructure search of small molecules similar to DMSO resulted in the identification of molecules with improved binding affinity. This work represents a clear example of the powerful interplay of molecular modelling and NMR. 相似文献
972.
Human MxA Protein Protects Mice Lacking a Functional Alpha/Beta Interferon System against La Crosse Virus and Other Lethal Viral Infections 总被引:14,自引:0,他引:14 下载免费PDF全文
Hans Peter Hefti Michael Frese Heinrich Landis Claudio Di Paolo Adriano Aguzzi Otto Haller Jovan Pavlovic 《Journal of virology》1999,73(8):6984-6991
The human MxA protein is part of the antiviral state induced by alpha/beta interferon (IFN-alpha/beta). MxA inhibits the multiplication of several RNA viruses in cell culture. However, its antiviral potential in vivo has not yet been fully explored. We have generated MxA-transgenic mice that lack a functional IFN system by crossing MxA-transgenic mice constitutively expressing MxA with genetically targeted (knockout) mice lacking the beta subunit of the IFN-alpha/beta receptor (IFNAR-1(-/-) mice). These mice are an ideal animal model to investigate the unique antiviral activity of human MxA in vivo, because they are unable to express other IFN-induced proteins. Here, we show that MxA confers resistance to Thogoto virus, La Crosse virus, and Semliki Forest virus. No Thogoto virus progeny was detectable in MxA-transgenic mice, indicating an efficient block of virus replication at the primary site of infection. In the case of La Crosse virus, MxA restricted invasion of the central nervous system. In contrast, Semliki Forest virus multiplication in the brain was detectable in both MxA-expressing and nonexpressing IFNAR-1(-/-) mice. However, viral titers were clearly reduced in MxA-transgenic mice. Our results demonstrate that MxA does not need the help of other IFN-induced proteins for activity but is a powerful antiviral agent on its own. Moreover, the results suggest that MxA may protect humans from potential fatal infections by La Crosse virus and other viral pathogens. 相似文献
973.
Luiz A. R. Freitas Lilian V. S. Carvalho Jonathan L. M. Fontes Cassiana S. Souza Reginaldo B. Santos Jr. Lara T. Cardoso Claudio P. Figueira Milton S. Fonseca Neto Rafael C. M. F. Dias Manuela S. Solc Marilda S. Gonalves Setondji C. M. A. Yahouedehou Ceuci L. X. Nunes Geraldo G. S. Oliveira Washington L. C. dosSantos 《Journal of cellular and molecular medicine》2021,25(21):10318
974.
Ettore Benedetti Michele Saviano Rosa Iacovino Carlo Pedone Antonello Santini Marco Crisma Fernando Formaggio Claudio Toniolo Quirinus B. Broxterman Johan Kamphuis 《Biopolymers》1998,46(7):433-443
The crystal-state preferred conformations of six Nα-blocked pentapeptide esters, each containing four helicogenic, achiral α-aminoisobutyric acid (Aib) residues followed by one chiral L -valine (L -Val) or Cα-methyl-L -valine [(αMe)Val] residue at the C-terminus, have been assessed by x-ray diffraction analysis. In all of the compounds the (Aib)4 sequence is folded in a regular 310-helical conformation. In the four pentapeptides characterized by the L -(αMe)Val residue two conformationally distinct molecules occur in the asymmetric unit. Conversely, only one molecule is observed in the asymmetric unit of two pentapeptides with the C-terminal L -Val residue. In the L -Val based peptides the helical screw sense of the (Aib)4 sequence is right-handed, whereas in the L (αMe)Val analogues both right- and left-handed helical screw senses concomitantly occur in the two crystallographically independent molecules. © 1998 John Wiley & Sons, Inc. Biopoly 46: 433–443, 1998 相似文献
975.
Lucia Banci Ivano Bertini Giovanni Gori Savellini Andrea Romagnoli Paola Turano Mauro A. Cremonini Claudio Luchinat Harry B. Gray 《Proteins》1997,29(1):68-76
The pseudocontact shifts of NMR signals, which arise from the magnetic susceptibility anisotropy of paramagnetic molecules, have been used as structural constraints under the form of a pseudopotential in the SANDER module of the AMBER 4.1 molecular dynamics software package. With this procedure, restrained energy minimization (REM) and restrained molecular dynamics (RMD) calculations can be performed on structural models by using pseudocontact shifts. The structure of the cyanide adduct of the Met80Ala mutant of the yeast iso-1-cytochrome c has been used for successfully testing the calculations. For this protein, a family of structures is available, which was obtained by using NOE and pseudocontact shifts as constraints in a distance geometry program. The structures obtained by REM and RMD calculations with the inclusion of pseudocontact shifts are analyzed. Proteins 29:68–76, 1997. © 1997 Wiley-Liss, Inc. 相似文献
976.
Dmitri I. Svergun Claudio Barberato Michel H. J. Koch Luc Fetler Patrice Vachette 《Proteins》1997,27(1):110-117
Solution scattering curves evaluated from the crystal structures of the T and R states of the allosteric enzyme aspartate transcarbamylase from Escherichia coli were compared with the experimental x-ray scattering patterns. Whereas the scattering from the crystal structure of the T state agrees with the experiment, large deviations reflecting a significant difference between the quaternary structures in the crystal and in solution are observed for the R state. The experimental curve of the R state was fitted by rigid body movements of the subunits in the crystal R structure which displace the latter further away from the T structure along the reaction coordinates of the T→R transition observed in the crystals. Taking the crystal R structure as a reference, it was found that in solution the distance between the catalytic trimers along the threefold axis is 0.34 nm larger and the trimers are rotated by 11° in opposite directions around the same axis; each of the three regulatory dimers is rotated by 9° around the corresponding twofold axis and displaced by 0.14 nm away from the molecular center along this axis. Proteins 27:110–117 © 1997 Wiley-Liss, Inc. 相似文献
977.
Undoubted lines of evidence point out that members of CYCLOIDEA (CYC) 2 clade are essential players to control flower symmetry and, amusingly, also are determinants of capitula architecture (pseudanthium). In several species, CYC-like genes influence the androecium patterning, but to date, the function of these genes in the development of gynoecium organs is less clear. In this review, we first reported details about floral symmetry and an overview of genes and molecular mechanisms regulating the development of zygomorphism in different angiosperm lineages (e.g., basal and core eudicots and monocots). Then, we paid emphasis on the role of CYC-like genes in the development of heterogamous inflorescence of sunflower as well as other Asteraceae and some species within the Dipsacaceae family. Helianthus annuus is particularly attractive because it represents a useful model to study the role of CYC-like genes on shaping floral corolla as well as the differentiation of reproductive organs in different flowers of pseudanthia. A special attention was reserved to inflorescence morphology mutants of sunflower (i.e., Chrysanthemoids2 and tubular ray flower) because they provide useful information on the role of CYC-like genes in the radiate capitulum evolution. Finally, we discuss data from literature to suggest that CYC-like genes are also co-opted to regulate stamen and carpel differentiation likely throughout their interaction with the cell cycle and flower organ identity genes. The recruitment of reproductive organs in ray flowers also supports the phylogenetic origin of a radiate inflorescence of sunflower from a discoid capitulum and suggests that in sterile zygomorphic ray flower primordia the latent identity to differentiate both microsporangium and macrosporangium was conserved. 相似文献
978.
Elisa Bisicchia Laura Latini Virve Cavallucci Valeria Sasso Vanessa Nicolin Marco Molinari Marcello D’Amelio Maria Teresa Viscomi 《Molecular neurobiology》2017,54(7):4896-4907
Spinal cord injuries (SCIs) are devastating conditions of the central nervous system (CNS) for which there are no restorative therapies. Neuronal death at the primary lesion site and in remote regions that are functionally connected to it is one of the major contributors to neurological deficits following SCI.Disruption of autophagic flux induces neuronal death in many CNS injuries, but its mechanism and relationship with remote cell death after SCI are unknown. We examined the function and effects of the modulation of autophagy on the fate of axotomized rubrospinal neurons in a rat model of spinal cord dorsal hemisection (SCH) at the cervical level. Following SCH, we observed an accumulation of LC3-positive autophagosomes (APs) in the axotomized neurons 1 and 5 days after injury. Furthermore, this accumulation was not attributed to greater initiation of autophagy but was caused by a decrease in AP clearance, as demonstrated by the build-up of p62, a widely used marker of the induction of autophagy. In axotomized rubrospinal neurons, the disruption of autophagic flux correlated strongly with remote neuronal death and worse functional recovery. Inhibition of AP biogenesis by 3-methyladenine (3-MA) significantly attenuated remote degeneration and improved spontaneous functional recovery, consistent with the detrimental effects of autophagy in remote damage after SCH. Collectively, our results demonstrate that autophagic flux is blocked in axotomized neurons on SCI and that the inhibition of AP formation improves their survival. Thus, autophagy is a promising target for the development of therapeutic interventions in the treatment of SCIs. 相似文献
979.
Molecular phylogeography of Troglophilus cave crickets (Orthoptera,Rhaphidophoridae): A combination of vicariance and dispersal drove diversification in the East Mediterranean region 下载免费PDF全文
Giuliana Allegrucci Valerio Ketmaier Claudio Di Russo Mauro Rampini Valerio Sbordoni Marina Cobolli 《Journal of Zoological Systematics and Evolutionary Research》2017,55(4):310-325
In this study, we investigated the molecular phylogenetic divergence and historical biogeography of cave crickets belonging to the genus Troglophilus (Orthoptera, Rhaphidophoridae) from caves in eastern Mediterranean and Anatolia regions. Three mitochondrial DNA genes (COI, 12S rDNA, and 16S rDNA) and two nuclear ones (18S rDNA and 28S rDNA) were amplified and partially sequenced to reconstruct phylogenetic relationships among most of the known Troglophilus species. Results showed a well‐resolved phylogeny with three main clades representing the Balkan, the Anatolian, and the Cycladian–Cretan lineages. Based on Bayesian analyses, we applied a relaxed molecular clock model to estimate the divergence times between these three lineages. Dating estimates indicate that radiation of the ingroup might have been triggered by the opening of the Mid‐Aegean trench, while the uplift of the Anatolian Plateau in Turkey and the changes of relief, emergence, and disappearance of orographic and hydrographical barriers in the Balkan Peninsula are potential paleogeographic events responsible for the initial diversification of the genus Troglophilus. A possible biogeographic scenario, reconstructed using S‐DIVA with RASP software, suggested that the current distribution of Troglophilus species can be explained by a combination of both dispersal and vicariance events that occurred in particular in the ancestral populations. The radiation of Troglophilus species likely started from the Aegean and proceeded eastward to Anatolia and westward to the Balkan region. Results are additionally compared to those available for Dolichopoda, the only other representative genus of Rhaphidophoridae present in the Mediterranean area. 相似文献
980.
Quartaroli Larissa Silva Lívia C. Fidélis Silva Claudio Mudadu Lima Helena Santiago de Paula Sergio Oliveira de Oliveira Valéria Maia de Cássia S. da Silva Marliane Kasuya Maria Catarina M. de Sousa Maíra Paula Torres Ana Paula R. Souza Rodrigo Suhett Bassin João Paulo da Silva Cynthia Canêdo 《Applied microbiology and biotechnology》2017,101(2):859-870
Applied Microbiology and Biotechnology - Water generated during oil exploration is chemically complex and contains high concentrations of ammonium and, in some cases, high salinity. The most common... 相似文献