478 research outputs found
Augustin Daly; Certain Writings on His Life and Livelihood
The American theatre of the early nineteenth century was strongly dependent upon the European theatre. American theatre goers looked across the ocean to import talent, playwrights, plays, and actors. Not until mid-century did America begin to develop its wold-wide theatre influence. Specifically, the latter half of the nineteenth century yielded one of the most influential director/playwrights of the American theatre until that time. Modern American drama begins with Augustin Daly (Quinn 1).
John Augustin Daly, the son of an American sea captain and a British Lieutenant\u27s daughter, was born on the seventh of July, 1838 in Plymouth, North Carolina (Johnson 8). His father died soon after his birth, so his mother moved to New York City where Daly developed his strict Catholic faith, a loyalty he maintained until his death in 1899 (Winter, Vagrant Memories 246). From the outset, the young Daly had a passion for the theatre; but not as an actor but as a new creative force, the director. Judge Joseph Daly, Augustin\u27s older brother, attributes (at least partially) his desire for directing to Daly\u27s disheartening first acting experience
Analyses of tissue culture adaptation of human Herpesvirus-6A by whole genome deep sequencing redefines the reference sequence and identifies virus entry complex changes
Tissue-culture adaptation of viruses can modulate infection. Laboratory passage and bacterial artificial chromosome (BAC)mid cloning of human cytomegalovirus, HCMV, resulted in genomic deletions and rearrangements altering genes encoding the virus entry complex, which affected cellular tropism, virulence, and vaccine development. Here, we analyse these effects on the reference genome for related betaherpesviruses, Roseolovirus, human herpesvirus 6A (HHV-6A) strain U1102. This virus is also naturally âclonedâ by germline subtelomeric chromosomal-integration in approximately 1% of human populations, and accurate references are key to understanding pathological relationships between exogenous and endogenous virus. Using whole genome next-generation deep-sequencing Illumina-based methods, we compared the original isolate to tissue-culture passaged and the BACmid-cloned virus. This re-defined the reference genome showing 32 corrections and 5 polymorphisms. Furthermore, minor variant analyses of passaged and BACmid virus identified emerging populations of a further 32 single nucleotide polymorphisms (SNPs) in 10 loci, half non-synonymous indicating cell-culture selection. Analyses of the BAC-virus genome showed deletion of the BAC cassette via loxP recombination removing green fluorescent protein (GFP)-based selection. As shown for HCMV culture effects, select HHV-6A SNPs mapped to genes encoding mediators of virus cellular entry, including virus envelope glycoprotein genes gB and the gH/gL complex. Comparative models suggest stabilisation of the post-fusion conformation. These SNPs are essential to consider in vaccine-design, antimicrobial-resistance, and pathogenesis
The structure of Herpesvirus Fusion Glycoprotein B-Bilayer Complex reveals the protein-membrane and lateral protein-protein interaction
Glycoprotein B (gB) is a key component of the complex herpesvirus fusion machinery. We studied membrane interaction of two gB ectodomain forms and present an electron cryotomography structure of the gB-bilayer complex. The two forms differed in presence or absence of the membrane proximal region (MPR) but showed an overall similar trimeric shape. The presence of the MPR impeded interaction with liposomes. In contrast, the MPR-lacking form interacted efficiently with liposomes. Lateral interaction resulted in coat formation on the membranes. The structure revealed that interaction of gB with membranes was mediated by the fusion loops and limited to the outer membrane leaflet. The observed intrinsic propensity of gB to cluster on membranes indicates an additional role of gB in driving the fusion process forward beyond the transient fusion pore opening and subsequently leading to fusion pore expansion
Co-based heterogeneous catalysts from well-defined Α-diimine complexes : Discussing the role of nitrogen
Ar-BIANs and related \uce\ub1-diimine Co complexes were wet impregnated onto Vulcan\uc2\uae XC 72 R carbon black powder and used as precursors for the synthesis of heterogeneous supported nanoscale catalysts by pyrolysis under argon at 800\uc2\ua0\uc2\ub0C. The catalytic materials feature a core-shell structure composed of metallic Co and Co oxides decorated with nitrogen-doped graphitic layers (NGr). These catalysts display high activity in the liquid phase hydrogenation of aromatic nitro compounds (110\uc2\ua0\uc2\ub0C, 50 bar H2) to give chemoselectively substituted aryl amines. The catalytic activity is closely related to the amount and type of nitrogen atoms in the final catalytic material, which suggests a heterolytic activation of dihydrogen
Critical assessment of methods of Protein Structure Prediction (CASP) â Round XIII
CASP (Critical Assessment of Structure Prediction) assesses the state of the art in
modeling protein structure from amino acid sequence. The most recent experiment
(CASP13 held in 2018) saw dramatic progress in structure modeling without use of
structural templates (historically âab initioâ modeling). Progress was driven by the
successful application of deep learning techniques to predict inter-residue distances. In
turn, these results drove dramatic improvements in three-dimensional structure
accuracy: With the proviso that there are an adequate number of sequences known for
the protein family, the new methods essentially solve the long-standing problem of
predicting the fold topology of monomeric proteins. Further, the number of sequences
required in the alignment has fallen substantially. There is also substantial improvement
in the accuracy of template-based models. Other areas - model refinement, accuracy
estimation, and the structure of protein assemblies - have again yielded interesting
results. CASP13 placed increased emphasis on the use of sparse data together with
modeling and chemical crosslinking, SAXS, and NMR all yielded more mature results.
This paper summarizes the key outcomes of CASP13. The special issue of PROTEINS
contains papers describing the CASP13 assessments in each modeling category and
contributions from the participants
Structural mass spectrometry decodes domain interaction and dynamics of the full-length Human Histone Deacetylase 2
Human Histone Deacetylase 2 (HDAC2) belongs to a conserved enzyme superfamily that regulates deacetylation inside cells. HDAC2 is a drug target as it is known to be upregulated in cancers and neurodegenerative disorders. It consists of a globular deacetylase and C-terminus intrinsically-disordered domains [1-3]. To date, there is no full-length structure of HDAC2 available due to the high intrinsic flexibility of its C-terminal domain. The intrinsically-disordered domain, however, is known to be important for the enzymatic function of HDAC2 [1, 4]. Here we combine several structural Mass Spectrometry (MS) methodologies such as denaturing, native, ion mobility and chemical crosslinking, alongside biochemical assays and molecular modelling to study the structure and dynamics of the full-length HDAC2 for the first time. We show that MS can easily dissect heterogeneity inherent within the protein sample and at the same time probe the structural arrangement of the different conformers present. Activity assays combined with data from MS and molecular modelling suggest how the structural dynamics of the C-terminal domain, and its interactions with the catalytic domain, regulate the activity of this enzyme
The EPN-TAP protocol for the Planetary Science Virtual Observatory
A Data Access Protocol has been set up to search and retrieve Planetary
Science data in general. This protocol will allow the user to select a subset
of data from an archive in a standard way, based on the IVOA Table Access
Protocol (TAP). The TAP mechanism is completed by an underlying Data Model and
reference dictionaries. This paper describes the principle of the EPN- TAP
protocol and interfaces, underlines the choices that have been made, and
discusses possible evolutions.Comment: 21 pages. Submitted to Astronomy & Computing, S.I. Virtual
Observator
Iron Age and Anglo-Saxon genomes from East England reveal British migration history
British population history has been shaped by a series of immigrations, including the early Anglo-Saxon migrations after 400 CE. It remains an open question how these events affected the genetic composition of the current British population. Here, we present whole-genome sequences from 10 individuals excavated close to Cambridge in the East of England, ranging from the late Iron Age to the middle Anglo-Saxon period. By analysing shared rare variants with hundreds of modern samples from Britain and Europe, we estimate that on average the contemporary East English population derives 38% of its ancestry from Anglo-Saxon migrations. We gain further insight with a new method, rarecoal, which infers population history and identifies fine-scale genetic ancestry from rare variants. Using rarecoal we find that the Anglo-Saxon samples are closely related to modern Dutch and Danish populations, while the Iron Age samples share ancestors with multiple Northern European populations including Britain
Identification by virtual screening and functional characterisation of novel positive and negative allosteric modulators of the α7 nicotinic acetylcholine receptor
Several previous studies have demonstrated that the activity of neurotransmitters acting on ligand-gated ion channels such as the nicotinic acetylcholine receptor (nAChR) can be altered by compounds binding to allosteric modulatory sites. In the case of α7 nAChRs, both positive and negative allosteric modulators (PAMs and NAMs) have been identified and have attracted considerable interest. A recent study, employing revised structural models of the transmembrane domain of the α7 nAChR in closed and open conformations, has provided support for an inter-subunit transmembrane allosteric binding site (Newcombe et al 2017). In the present study, we have performed virtual screening of the DrugBank database using pharmacophore queries that were based on the predicted binding mode of PAMs to α7 nAChR structural models. A total of 81 compounds were identified in the DrugBank database, of which the 25 highest-ranked hits corresponded to one of four previously-identified therapeutic compound groups (carbonic anhydrase inhibitors, cyclin-dependent kinase inhibitors, diuretics targeting the Na+-K+-Cl- cotransporter, and fluoroquinolone antibiotics targeting DNA gyrase). The top-ranked compound from each of these four groups (DB04763, DB08122, furosemide and pefloxacin, respectively) was tested for its effects on human α7 nAChR expressed in Xenopus oocytes using two-electrode voltage-clamp electrophysiology. These studies, conducted with wild-type, mutant and chimeric receptors, resulted in all four compounds exerting allosteric modulatory effects. While DB04763, DB08122 and pefloxacin were antagonists, furosemide potentiated ACh responses. Our findings, supported by docking studies, are consistent with these compounds acting as PAMs and NAMs of the α7 nAChR via interaction with a transmembrane site
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