Search results for "Membrane Fusion"
showing 4 items of 24 documents
Calcium-dependent conformational changes of membrane-bound Ebola fusion peptide drive vesicle fusion
2003
AbstractThe fusogenic subdomain of the Ebola virus envelope glycoprotein is an internal sequence located ca. 20 residues downstream the N-terminus of the glycoprotein transmembrane subunit. Partitioning of the Ebola fusion peptide into membranes containing phosphatidylinositol in the absence of Ca2+ stabilizes an α-helical conformation, and gives rise to vesicle efflux but not vesicle fusion. In the presence of millimolar Ca2+ the membrane-bound peptide adopts an extended β-structure, and induces inter-vesicle mixing of lipids. The peptide conformational polymorphism may be related to the flexibility of the virus–cell intermembrane fusogenic complex.
Dynamin-Like Proteins Are Potentially Involved in Membrane Dynamics within Chloroplasts and Cyanobacteria
2017
Dynamin-like proteins (DLPs) are a family of membrane-active proteins with low sequence identity. The proteins operate in different organelles in eukaryotic cells, where they trigger vesicle formation, membrane fusion, or organelle division. As discussed here, representatives of this protein family have also been identified in chloroplasts and DLPs are very common in cyanobacteria. Since cyanobacteria and chloroplasts, an organelle of bacterial origin, have similar internal membrane systems, we suggest that DLPs are involved in membrane dynamics in cyanobacteria and chloroplasts. Here, we discuss the features and activities of DLPs with a focus on their potential presence and activity in ch…
Interactions of membranes with coarse-grain proteins: a comparison
2012
We study the interactions between lipid bilayers and rigid transmembrane proteins by Monte Carlo simulations of generic coarse-grain models. Different popular protein models are considered and compared with each other, and key parameters such as the hydrophobicity and the hydrophobic mismatch are varied systematically. Furthermore, the properties of the membrane are manipulated by applying different tensions. The response of the membrane to the insertion of single proteins is found to be mostly generic and independent of the choice of the protein model. Likewise, the orientational distributions of single proteins depend mainly on the hydrophobic mismatch and the hydrophobicity of the protei…
Binding and internalization of human papillomavirus type 33 virus-like particles by eukaryotic cells
1995
Infection of cells by human papillomaviruses (HPVs) associated with malignant genital lesions has not been studied because of the lack of an in vitro system and the unavailability of virions. We have now used virus-like particles (VLPs) of HPV type 33 to analyze the initial events in the interaction of the HPV capsid with cell lines. Binding of VLPs to HeLa cells was observed in biochemical assays and by immunofluorescence. VLP binding was inhibited by antisera raised against VLPs but not by monoclonal antibodies recognizing either L1 or L2 epitopes accessible on VLPs. Under saturating conditions, approximately 2 x 10(4) VLPs were bound per cell, with a dissociation constant of about 100 pM…