Search results for "Interactions"
showing 10 items of 1963 documents
Crystallography of encapsulated molecules.
2017
The crystallography of supramolecular host–guest complexes is reviewed and discussed as a part of small molecule crystallography. In these complexes, the host binds the guests through weak supramolecular interactions, such as hydrogen and halogen bonding, cation–π, anion–π, C–H–π, π–π, C–H–anion interactions and the hydrophobic effect. As the guest often shows severe disorder, large thermal motion and low occupancies, the reliable crystallographic determination of the guest can be very demanding. The analysis of host–guest interactions using tools such as Hirshfeld and cavity volume surface analysis will help to look closely at the most important host–guest interactions. The jewel in the cr…
Fluorine Scan of Inhibitors of the Cysteine Protease Human Cathepsin L: Dipolar and Quadrupolar Effects in the π-Stacking of Fluorinated Phenyl Rings…
2016
The π-stacking of fluorinated benzene rings on protein backbone amide groups was investigated, using a dual approach comprising enzyme-ligand binding studies complemented by high-level quantum chemical calculations. In the experimental study, the phenyl substituent of triazine nitrile inhibitors of human cathepsin L (hCatL), which stacks onto the peptide amide bond Gly67-Gly68 at the entrance of the S3 pocket, was systematically fluorinated, and differences in inhibitory potency were measured in a fluorimetric assay. Binding affinity is influenced by lipophilicity (clog P), the dipole and quadrupole moments of the fluorinated rings, but also by additional interactions of the introduced fluo…
On the Study of Resonance Interactions and Splittings in the PH3 Molecule: ν1, ν3, ν2+ν4, and 2ν4 Bands
2002
International audience; The high-resolution (0.005 cm−1) Fourier transform infrared spectrum of PH3 is recorded and analyzed in the region of the fundamental stretching bands, ν1 and ν3. The ν2 + ν4 and 2ν4 bands are taken into account also. Experimental transitions are assigned to the ν1, ν3, ν2 + ν4, and 2ν4 bands with the maximum value of quantum number J equal to 15, 15, 13, and 15, respectively. a1–a2 splittings are observed and described up to the value of quantum number K equal to 10. The analysis of a1/a2 splittings is fulfilled with a Hamiltonian model which takes into account numerous resonance interactions among all the upper vibrational states
Measurement of hard double-parton interactions inW(???) + 2-jet events at $\sqrt{s}\,=7$ TeV with the ATLAS detector
2013
The production of W bosons in association with two jets in proton–proton collisions at a centre-of-mass energy of √s=7 TeV has been analysed for the presence of double-parton interactions using data corresponding to an integrated luminosity of 36 pb[superscript −1], collected with the ATLAS detector at the Large Hadron Collider. The fraction of events arising from double-parton interactions, f[superscript (D) over subscript DP], has been measured through the p[subscript T] balance between the two jets and amounts to f[superscript (D) over subscript DP] = 0.08 ± 0.01 (stat.) ± 0.02 (sys.) for jets with transverse momentum p[subscript T] > 20 GeV and rapidity |y| < 2.8. This corresponds to a …
Heart failure risk reduction:hydrophilic or lipophilic statins?
2020
[No abstract]
Girdles as the main infection site for Paradeontacylix kampachi (Sanguinicolidae) in the greater amberjack Seriola dumerili.
2003
In this study, we provide new information about the habitats selected by the blood fluke Paradeontacylix kampachi in the greater amberjack Seriola dumerili based on an exhaustive anatomical examination. From May to October 1998, 21 fish of the 0+ age class were collected from tanks of the Spanish Institute of Oceanography in Puerto de Mazarrón, Spain, for parasitological analysis. Individuals of P. kampachi were found in 17 of the 21 fish analysed (mean intensity +/- SD: 13.6 +/- 16.6; median: 6). Worms occurred in the girdles, cephalic kidney, sinus venosus, kidney and branchial arteries. A Friedman test with a post-hoc contrast revealed a significantly higher number of worms in the girdle…
Immune activation promotes evolutionary conservation of T-cell epitopes in HIV-1.
2013
The immune system should constitute a strong selective pressure promoting viral genetic diversity and evolution. However, HIV shows lower sequence variability at T-cell epitopes than elsewhere in the genome, in contrast with other human RNA viruses. Here, we propose that epitope conservation is a consequence of the particular interactions established between HIV and the immune system. On one hand, epitope recognition triggers an anti-HIV response mediated by cytotoxic T-lymphocytes (CTLs), but on the other hand, activation of CD4(+) helper T lymphocytes (TH cells) promotes HIV replication. Mathematical modeling of these opposite selective forces revealed that selection at the intrapatient l…
Hemocytes of Rhynchophorus ferrugineus (Olivier)(Coleoptera: Curculionidae) and their response to Saccharomyces cerevisiae and Bacillus thuringiensis
2011
Originally from tropical Asia, the Red Palm Weevil (RPW Rhynchophorus ferrugineus (Olivier) is the most dangerous and deadly pest of many palm trees, and there have been reports of its recent detection in France, Greece and Italy. At present, emphasis is on the development of integrated pest management based on biological control rather than on chemical insecticides, however the success of both systems is often insufficient. In this regard, RPW appears to be one pest that is very difficult to control. Thus inves- tigations into the natural defences of this curculionid are advisable. RPW hemocytes, the main immuno- competent cells in the insect, are described for the first time. We identifie…
Hepatitis B subviral envelope particles use the COPII machinery for intracellular transport via selective exploitation of Sec24A and Sec23B
2020
Hepatitis B virus (HBV) is a leading cause of liver disease. Its success as a human pathogen is related to the immense production of subviral envelope particles (SVPs) contributing to viral persistence by interfering with immune functions. To explore cellular pathways involved in SVP formation and egress, we investigated host-pathogen interactions. Yeast-based proteomics revealed Sec24A, a component of the coat protein complex II (COPII), as an interaction partner of the HBV envelope S domain. To understand how HBV co-opts COPII as a proviral machinery, we studied roles of key Sec proteins in HBV-expressing liver cells. Silencing of Sar1, Sec23, and Sec24, which promote COPII assembly conco…
Hepatitis B Virus Large Envelope Protein Interacts with γ2-Adaptin, a Clathrin Adaptor-Related Protein
2001
ABSTRACT For the outcome of a hepatitis B virus (HBV) infection, the viral L envelope protein with its pre-S domain performs pivotal functions by mediating attachment of HBV to liver cells, envelopment of viral capsids, release of (sub)viral particles, regulation of supercoiled DNA amplification, and transcriptional transactivation. To assess its multiple functions and host-protein assistance involved, we initiated a two-hybrid screen using the L-specific pre-S1 domain as bait. With this approach, we have identified γ2-adaptin, a putative member of the clathrin adaptor proteins responsible for protein sorting and trafficking, as a specific binding partner of L protein. Evidence for a physic…