Acidianus filamentous virus 1 coat proteins display a helical fold spanning the filamentous archaeal viruses lineage.

Acidianus filamentous virus 1 (AFV1), a member of the Lipothrixviridae family, infects the hyperthermophilic, acidophilic crenarchaeaon Acidianus hospitalis. The virion, covered with a lipidic outer shell, is 9,100-A long and contains a 20.8-kb linear dsDNA genome.

Synthesis and antiprotozoal activity of 4-arylcoumarins.

A large series of 4-arylcoumarins was synthesized by Suzuki-Miyaura cross-coupling reaction and evaluated for antiprotozoal activity against Plasmodium falciparum and Leishmania donovani. Several compounds were found to strongly inhibit the proliferation of human cell line and/or parasites. The 4-(3,4-dimethoxyphenyl)-6,7-dimethoxycoumarin exhibit a potent activity on L.

Effect of in the mobile phase on the critical conditions of poly(ethylene glycol) in liquid chromatography-mass spectrometry coupling.

The nature of salts introduced in the chromatographic mobile phase to promote on-line electrospray ionization was shown to be a key parameter in the optimization of LCCC-MS couplings, both using non-polar (Si-C18) and polar (Si-NH2) stationary phases. The critical conditions of poly(ethylene glycol), which reflect a compensation process between exclusion and interaction effects, were strongly modified when changing the size of the cation in the eluent. This phenomenon could be attributed to interactions between the cation and water molecules from the mobile phase, in the case of the non-polar stationary phase, giving rise to a salting out effect due to a lowered solvent quality of the eluent; or between the cation and amino-modified silanols of the polar stationary phase, inducing a decrease of the surface adsorptivity.

Molecular basis for galactosylation of core fucose residues in invertebrates: identification of caenorhabditis elegans N-glycan core alpha1,6-fucoside beta1,4-galactosyltransferase GALT-1 as a member of a novel glycosyltransferase family.

Galectin CGL2 from the ink cap mushroom Coprinopsis cinerea displays toxicity toward the model nematode Caenorhabditis elegans. A mutation in a putative glycosyltransferase-encoding gene resulted in a CGL2-resistant C. elegans strain characterized by N-glycans lacking the beta1,4-galactoside linked to the alpha1,6-linked core fucose.

Structural characterization of a poly(methacrylic acid)-poly(methyl methacrylate) copolymer by nuclear magnetic resonance and mass spectrometry.

Mass spectrometry (MS) and nuclear magnetic resonance (NMR) have been combined to achieve the complete microstructural characterization of a poly(methacrylic acid)-poly(methyl methacrylate) (PMAA-PMMA) copolymer synthesized by nitroxide-mediated polymerization. Various PMAA-PMMA species could be identified which mainly differ in terms of terminaisons. 1H and 13C NMR experiments revealed the structure of the end-groups as well as the proportion of each co-monomer in the copolymers.

Improved compositional analysis of block copolymers using diffusion ordered NMR spectroscopy.

Block copolymers constitute a fascinating class of polymeric materials that are used in a broad range of applications. The performance of these materials is highly coupled to the physical and chemical properties of the constituting block copolymers. Traditionally, the composition of block copolymers is obtained by 1H NMR spectroscopy on purified copolymer fractions.

A fortified street food to prevent nutritional deficiencies in homeless men in France.

Objective: To develop a food policy approach to prevent nutritional deficiencies and malnutrition in homeless men in France.

Study Population And Methods: A dietary survey was conducted among homeless men visiting an emergency shelter in Paris to assess their nutritional status and the quality of food aid provided. The use of a fortified food easy to eat in the street was identified as the best strategy to improve nutrient intake in this population.

Nucleophile addition of reduced glutathione on 2-methyl-2-nitroso compound: a combined electron paramagnetic resonance spectroscopy and electrospray tandem mass spectrometry study.

Mass spectrometry (MS) was used in conjunction with electron paramagnetic resonance (EPR) to characterize products arising from reactions between reduced glutathione (GSH) and 2-methyl 2-nitroso propane (MNP) in an oxidative medium, to evaluate the reactivity of this tripeptide as a nucleophile toward a nitroso compound. Depending on the experimental conditions, different radical species could be detected by EPR, which allowed some structural assumptions. These samples were then submitted to electrospray ionization, in both positive and negative ion modes, for structural elucidation in tandem mass spectrometry.

Molecular weight determination of block copolymers by pulsed gradient spin echo NMR.

Matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) is the technique of choice to achieve molecular weight data for synthetic polymers. Because the success of a MALDI-MS analysis critically depends on a proper matrix and cation selection, which in turn relates closely to the polymer chemical nature and size, prior estimation of the polymer size range strongly helps in rationalizing MALDI sample preparation. We recently showed how pulsed gradient spin echo (PGSE) nuclear magnetic resonance could be used as an advantageous alternative to size exclusion chromatography, to rationalize MALDI sample preparation and confidently interpret MALDI mass spectra for homopolymers.

Crystal structure and function of a DARPin neutralizing inhibitor of lactococcal phage TP901-1: comparison of DARPin and camelid VHH binding mode.

Combinatorial libraries of designed ankyrin repeat proteins (DARPins) have been proven to be a valuable source of specific binding proteins, as they can be expressed at very high levels and are very stable. We report here the selection of DARPins directed against a macromolecular multiprotein complex, the baseplate BppUxBppL complex of the lactococcal phage TP901-1. Using ribosome display, we selected several DARPins that bound specifically to the tip of the receptor-binding protein (RBP, the BppL trimer).

High affinity binding between Hsp70 and the C-terminal domain of the measles virus nucleoprotein requires an Hsp40 co-chaperone.

The major inducible 70 kDa heat shock protein (hsp70) binds the measles virus (MeV) nucleocapsid with high affinity in an ATP-dependent manner, stimulating viral transcription and genome replication, and profoundly influencing virulence in mouse models of brain infection. Binding is mediated by two hydrophobic motifs (Box-2 and Box-3) located within the C-terminal domain (N(TAIL)) of the nucleocapsid protein, with N(TAIL) being an intrinsically disordered domain. The current work showed that high affinity hsp70 binding to N(TAIL) requires an hsp40 co-chaperone that interacts primarily with the hsp70 nucleotide binding domain (NBD) and displays no significant affinity for N(TAIL).

Solid state nuclear magnetic resonance as a tool to explore solvent-free MALDI samples.

Solid-state Nuclear magnetic resonance (NMR) was used here to explore structural characteristics of samples to be subjected to matrix-assisted laser desorption/ionization (MALDI) and prepared without the use of any solvent. The analytical systems scrutinized in NMR were mixtures of a 2,5-dihydroxybenzoic acid (2,5-DHB) matrix and caesium fluoride (CsF), used as the cationization agent in synthetic polymer MALDI mass analysis, at different molar ratios (1:1, 5:1, and 10:1). Complementary information could be obtained from 13C, 133Cs, and 19F NMR spectra.

Post-genomic insights into the plant polysaccharide degradation potential of Aspergillus nidulans and comparison to Aspergillus niger and Aspergillus oryzae.

The plant polysaccharide degradative potential of Aspergillus nidulans was analysed in detail and compared to that of Aspergillus niger and Aspergillus oryzae using a combination of bioinformatics, physiology and transcriptomics. Manual verification indicated that 28.4% of the A.

The interaction between the measles virus nucleoprotein and the Interferon Regulator Factor 3 relies on a specific cellular environment.

Background: The genome of measles virus consists of a non-segmented single-stranded RNA molecule of negative polarity, which is encapsidated by the viral nucleoprotein (N) within a helical nucleocapsid. The N protein possesses an intrinsically disordered C-terminal domain (aa 401-525, N(TAIL)) that is exposed at the surface of the viral nucleopcapsid. Thanks to its flexible nature, N(TAIL) interacts with several viral and cellular partners.

Positive mode electrospray tandem mass spectrometry of poly(methacrylic acid) oligomers.

The dissociation of small poly(methacrylic acid) (PMAA) cations produced by electrospray was characterized by tandem mass spectrometry. Similarly to PMAA ions produced in the negative ion mode, the two electrosprayed cationic forms, namely [PMAA+Na](+) and [PMAA-H+2Na](+), were shown to fragment via a major pathway consisting of successive dehydration steps. Elimination of a water molecule would occur between two consecutive acid groups in a charged-remote mechanism and was shown to proceed as many times as pairs of acidic pendant groups were available.

Tuning block copolymer structural information by adjusting salt concentration in liquid chromatography at critical conditions coupled with electrospray tandem mass spectrometry.

Different cationic adducts of poly(ethylene oxide)/polystyrene block co-oligomers could be produced by adjusting the salt concentration in the mobile phase using a coupling between liquid chromatography at critical conditions and electrospray ionization mass spectrometry. Formation of doubly lithiated adducts was observed at high LiCl concentration (1 mM) while lowering the salt concentration down to 0.1 mM allowed co-oligomers to be ionized with both a proton and a lithium.

Crystal structure of a chimeric receptor binding protein constructed from two lactococcal phages.

Lactococcus lactis, a gram-positive bacterium widely used by the dairy industry to manufacture cheeses, is subject to infection by a diverse population of virulent phages. We have previously determined the structures of three receptor binding proteins (RBPs) from lactococcal phages TP901-1, p2, and bIL170, each of them having a distinct host range. Virulent phages p2 and bIL170 are classified within the 936 group, while the temperate phage TP901-1 is a member of the genetically distinct P335 polythetic group.

Cytokine control of adult neural stem cells.

The neuropoietic cytokine family includes interleukin-6 (IL-6), leukemia inhibitory factor (LIF), and ciliary neurotrophic factor (CNTF), among others. These cytokines have been shown to alter neural stem cell (NSC) self-renewal and progenitor cell division and differentiation, which could be mediated by the Janus kinase-signal transducer and activator of transcription (JAK/STAT) pathway. Using neurospheres from the adult mouse subventricular zone (SVZ), we found that acute or chronic exposure to LIF or CNTF differentially affects sphere development and sphere growth.

Nucleocapsid structure and function.

Measles virus belongs to the Paramyxoviridae family within the Mononegavirales order. Its nonsegmented, single-stranded, negative-sense RNA genome is encapsidated by the nucleoprotein (N) to form a helical nucleocapsid. This ribonucleoproteic complex is the substrate for both transcription and replication.

Comparative secretome analyses of two Trichoderma reesei RUT-C30 and CL847 hypersecretory strains.

Background: Due to its capacity to produce large amounts of cellulases, Trichoderma reesei is increasingly been researched in various fields of white biotechnology, especially in biofuel production from lignocellulosic biomass. The commercial enzyme mixtures produced at industrial scales are not well characterized, and their proteinaceous components are poorly identified and quantified. The development of proteomic methods has made it possible to comprehensively overview the enzymes involved in lignocellulosic biomass degradation which are secreted under various environmental conditions.

Mapping of a copper-binding site on the small CP12 chloroplastic protein of Chlamydomonas reinhardtii using top-down mass spectrometry and site-directed mutagenesis.

CP12 is a small chloroplastic protein involved in the Calvin cycle that was shown to bind copper, a metal ion that is involved in the transition of CP12 from a reduced to an oxidized state. In order to describe CP12's copper-binding properties, copper-IMAC experiments and site-directed mutagenesis based on computational modelling, were coupled with top-down MS [electrospray-ionization MS and MS/MS (tandem MS)]. Immobilized-copper-ion-affinity-chromatographic experiments allowed the primary characterization of the effects of mutation on copper binding.

Using solvent-free sample preparation to promote protonation of poly(ethylene oxide)s with labile end-groups in matrix-assisted laser desorption/ionisation.

Protonation is usually required to observe intact ions during matrix-assisted laser desorption/ionization (MALDI) of polymers containing fragile end-groups while cation adduction induces chain-end degradation. These polymers, generally obtained via living free radical polymerization techniques, are terminated with a functionality in which a bond is prone to homolytic cleavage, as required by the polymerization process. A solvent-free sample preparation method was used here to avoid salt contaminant from the solvent traditionally used in the dried-droplet MALDI procedure.

On-line coupling of liquid chromatography at critical conditions with electrospray ionization tandem mass spectrometry for the characterization of a nitroxide-mediated poly(ethylene oxide)/polystyrene block copolymer.

Coupling of liquid chromatography at critical conditions (LCCC) with on-line mass spectrometry (MS) detection was implemented via an electrospray ionization (ESI) interface, using a mobile phase containing the cationizing agent. Critical conditions established for poly(ethylene oxide) were used to characterize a poly(ethylene oxide)/polystyrene block copolymer (PEO-b-PS) in both MS and MS/MS modes. As co-oligomer molecules were successfully separated according to the PS block size, structural information could be reached from simplified MS spectra.

Tandem mass spectrometry of poly(methacrylic Acid) oligomers produced by negative mode electrospray ionization.

Dissociation of small poly(methyl acrylic acid) (PMAA) anions produced by electrospray was characterized by tandem mass spectrometry. Upon collisional activation, singly, and doubly deprotonated PMAA oligomers were shown to fragment via two major reactions, dehydration and decarboxylation. The elimination of a water molecule would occur between two consecutive acid groups in a charged-remote mechanism, giving rise to cyclic anhydrides, and was shown to proceed as many times as pairs of neutral pendant groups were available.

MeDor: a metaserver for predicting protein disorder.

Background: We have previously shown that using multiple prediction methods improves the accuracy of disorder predictions. It is, however, a time-consuming procedure, since individual outputs of multiple predictions have to be retrieved, compared to each other and a comprehensive view of the results can only be obtained through a manual, fastidious, non-automated procedure. We herein describe a new web metaserver, MeDor, which allows fast, simultaneous analysis of a query sequence by multiple predictors and provides a graphical interface with a unified view of the outputs.