Search results for "Viral membrane"
showing 5 items of 5 documents
Viral membrane protein topology is dictated by multiple determinants in its sequence.
2009
The targeting, insertion, and topology of membrane proteins have been extensively studied in both prokaryotes and eukaryotes. However, the mechanisms used by viral membrane proteins to generate the correct topology within cellular membranes are less well understood. Here, the effect of flanking charges and the hydrophobicity of the N-terminal hydrophobic segment on viral membrane protein topogenesis are examined systematically. Experimental data reveal that the classical topological determinants have only a minor effect on the overall topology of p9, a plant viral movement protein. Since only a few individual sequence alterations cause an inversion of p9 topology, its topological stability …
Genetics for Pseudoalteromonas provides tools to manipulate marine bacterial virus PM2
2008
ABSTRACT The genetic manipulation of marine double-stranded DNA (dsDNA) bacteriophage PM2 ( Corticoviridae ) has been limited so far. The isolation of an autonomously replicating DNA element of Pseudoalteromonas haloplanktis TAC125 and construction of a shuttle vector replicating in both Escherichia coli and Pseudoalteromonas enabled us to design a set of conjugative shuttle plasmids encoding tRNA suppressors for amber mutations. Using a host strain carrying a suppressor plasmid allows the introduction and analysis of nonsense mutations in PM2. Here, we describe the isolation and characterization of a suppressor-sensitive PM2 sus2 mutant deficient in the structural protein P10. To infect an…
Properties of baculovirus particles displaying GFP analyzed by fluorescence correlation spectroscopy.
2003
Abstract Recombinant baculovirus particles displaying green fluorescent protein (GFP) fused to the major envelope glycoprotein gp64 of the Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) were characterized by fluorescence correlation spectroscopy (FCS). FCS detected Brownian motion of single, intact recombinant baculovirus display particles with a diffusion coefficient (D) of (2.89±0.74)10 8 cm2s 1 and an apparent hydrodynamic radius of 83.35±21.22 nm. In the presence of sodium dodecyl sulfate (SDS), Triton X-100, and octylglucoside, the diffusion time was reduced to the 0.2 ms range (D = 7.5710 7 cm2s 1), showing that the fusion proteins were anchored in the viral envelope…
Sec61alpha and TRAM are Sequentially Adjacent to a Nascent Viral Membrane Protein during its ER Integration
2007
Co-translational integration of a nascent viral membrane protein into the endoplasmic reticulum membrane takes place via the translocon. We have been studying the early stages of the integration of a double-spanning plant viral movement protein to gain insights into how viral membrane proteins are transferred from the hydrophilic interior of the translocon into the hydrophobic environment of the bilayer, where the transmembrane (TM) segments of the viral proteins can diffuse freely. Photocrosslinking experiments reveal that this integration involves the sequential passage of the TM segments past Sec61alpha and translocating chain-associating membrane protein (TRAM). Each TM segment is first…
The closest relatives of icosahedral viruses of thermophilic bacteria are among viruses and plasmids of the halophilic archaea.
2009
We have sequenced the genome and identified the structural proteins and lipids of the novel membranecontaining, icosahedral virus P23-77 of Thermus thermophilus. P23-77 has an 17-kb circular double-stranded DNA genome, which was annotated to contain 37 putative genes. Virions were subjected to dissociation analysis, and five protein species were shown to associate with the internal viral membrane, while three were constituents of the protein capsid. Analysis of the bacteriophage genome revealed it to be evolutionarily related to another Thermus phage (IN93), archaeal Halobacterium plasmid (pHH205), a genetic element integrated into Haloarcula genome (designated here as IHP for integrated Ha…