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R W Compans

Publications and source records attributed to R W Compans.

At least 253 records · Page 14Linked to original sources
PubMed1972

Structure of the ribonucleoprotein of influenza virus.

The ribonucleoprotein (RNP) internal components of influenza virus were separated into distinct size classes by sedimentation in glycerol gradients and examined by electron microscopy by using positive staining with uranyl acetate. The large RNP have a peak in length distribution at 90 to 110 nm, the medium, at 60 to 90 nm, and the small, at 30 to 50 nm. These lengths can be correlated with the estimated molecular weights of the ribonucleic acids contained in the various RNP size classes. The RNP structure appears to consist of a strand which is folded back on itself and coiled in a regular double-helical arrangement.

Animals↗
PubMed1971

Spin-labeled electron spin resonance study of the lipid-containing membrane of influenza virus.

The organization of the lipid-containing membrane of influenza virus has been studied by the use of three different lipid spin labels, and the results are compared with a parallel study on human erythrocyte ghosts. The lipid phase of the viral membrane is slightly more rigid than that of the erythrocyte ghosts. The data suggest that the viral lipid is arranged in a bilayer. The data suggest that the viral lipid is arranged in a bilayer. The glycoprotein spikes covering the viral membrane were specifically removed by proteases, and no alteration in the environment of any of the three spin labels was detected. This suggests that the spikes are not involved in determining the organization of the lipid bilayer.

Cell Membrane↗
PubMed1971

Proteins and glycoproteins of paramyxoviruses: a comparison of simian virus 5, Newcastle disease virus, and Sendai virus.

The polypeptides of three paramyxoviruses (simian virus 5, Newcastle disease virus, and Sendai virus) were separated by polyacrylamide gel electrophoresis. Glycoproteins were identified by the use of radioactive glucosamine as a carbohydrate precursor. The protein patterns reveal similarities among the three viruses. Each virus contains at least five or six proteins, two of which are glycoproteins. Four of the proteins found in each virus share common features with corresponding proteins in the other two viruses, including similar molecular weights. These four proteins are the nucleocapsid protein (molecular weight 56,000 to 61,000), a larger glycoprotein (molecular weight 65,000 to 74,000), a smaller glycoprotein (molecular weight 53,000 to 56,000), and a major protein which is the smallest protein in each virion (molecular weight 38,000 to 41,000).

Acrylates↗
PubMed1971

Proteins of vesicular stomatitis virus and of phenotypically mixed vesicular stomatitis virus-simian virus 5 virions.

The identity of the glycoprotein of vesicular stomatitis virus (VSV) as the spike protein has been confirmed by the removal of the spikes with a protease from Streptomyces griseus, leaving bullet-shaped particles bounded by a smooth membrane. This treatment removes the glycoprotein but does not affect the other virion proteins, apparently because they are protected from the enzyme by the lipids in the viral membrane. The proteins of phenotypically mixed, bullet-shaped virions produced by cells mixedly infected with VSV and the parainfluenza virus simian virus 5 (SV5) have been analyzed by polyacrylamide gel electrophoresis. These virions contain all the VSV proteins plus the two SV5 spike proteins, both of which are glycoproteins. The finding of the SV5 spike glycoproteins on virions with the typical morphology of VSV indicates that there is not a stringent requirement that only the VSV glycoprotein can be used to form the bullet-shaped virion. On the other hand, the SV5 nucleocapsid protein and the major non-spike protein of the SV5 envelope were not detected in the phenotypically mixed virions, and this suggests that a specific interaction between the VSV nucleocapsid and regions of the cell membrane which contain the nonglycosylated VSV envelope protein is necessary for assembly of the bullet-shaped virion.

Amino Acids↗
PubMed1970

Phenotypic mixing of envelope proteins of the parainfluenza virus SV5 and vesicular stomatitis virus.

Cells mixedly infected with parainfluenza virus SV5 and vesicular stomatitis virus (VSV) yield phenotypically mixed virions, in addition to both parental types. Two types of phenotypically mixed virions have been identified: 0.6 to 1.2% of the VSV plaque formers were neutralized by SV5 antiserum, but not by VSV antiserum, suggesting the presence of a VSV genome in an SV5 envelope; 9 to 45% of the VSV plaque formers were neutralized by both antisera, indicating the presence of both SV5 and VSV antigens in their envelopes. The presence of SV5 antigen in virions with the typical bullet-shaped appearance of VSV was confirmed with ferritin-labeled anti-SV5 antibody. In contrast to standard VSV, phenotypically mixed virions adsorbed to and eluted from chicken erythrocytes, indicating that these virions contained in their envelopes SV5 hemagglutinin, and possibly neuraminidase. Thus, the VSV nucleocapsid can interact with membranes which contain SV5 proteins in the manner which leads to virus maturation, and the production of a high yield of phenotypically mixed virions with the morphology of VSV indicates that this process can function efficiently. No evidence of genetic recombination between the two viruses was found. These results raise the possibility of an evolutionary relatedness between the paramyxoviruses and the rhabdoviruses.

Adsorption↗
PubMed1970

Structure and cytopathic effects of Nelson Bay virus.

A virus isolated from a flying fox (Pteropus poliocephalus) has a morphology similar to that of reoviruses. However, unlike the reoviruses, this virus has a rapid cytopathic effect, causing cell fusion, vacuolization of the cytoplasm, and an unusual nuclear degeneration. Immunofluorescence indicates that viral antigen is distributed through both nucleus and cytoplasm. Viral maturation appears to take place in discrete cytoplasmic factories, and there is no apparent involvement of spindle tubules.

Animals↗
PubMed1970

Nucleocapsid protein subunits of simian virus 5, Newcastle disease virus, and Sendai virus.

Helical nucleocapsids of each of the paramyxoviruses simian virus 5 (SV5), Newcastle disease virus (NDV), and Sendai virus have been isolated in two different forms. One form contains larger protein subunits and is obtained from mature virions or infected cells dispersed by ethylenediaminetetraacetic acid. The other form possesses smaller subunits and is obtained from infected cells dispersed by trypsin. The estimated molecular weights of the larger subunits in the three viruses are similar: SV5, 61,000; Sendai virus, 60,000; NDV, 56,000. The smaller nucleocapsid subunits are also very similar: SV5, 43,000; Sendai virus, 46,000; NDV, 47,000. The helical nucleocapsid composed of the smaller subunit appears to be less flexible and more stable than that formed by the larger subunit. There is suggestive evidence that conversion of the larger subunit to the smaller by proteolytic cleavage may occur intracellularly. The possibility that such a mechanism could be involved in the accumulation of nucleocapsid in cells persistently infected with paramyxoviruses is discussed.

Acrylates↗