- Volume 45, Issue 2, 1979

The serological relationship between viruses producing varicella-like exanthems in several subhuman primates, varicella-zoster virus (VZV) and herpes simplex viruses (HSV) types 1 and 2, was investigated. All the primate viruses were related to VZV and some to HSV also. These results show that there is a group of varicella viruses, comprising four distinct entities, some of which may be useful for the establishment of an animal model for varicella.

3H-fucose and 14C-glucosamine labelled glycopeptides of the individual membrane proteins E1, E2 and E3 of Semliki Forest virus could be sequentially digested with α-neuraminidase, β-galactosidase, N-acetyl-β-glucosaminidase, α- and β-mannosidase, N-acetyl-β-hexosaminidase and finally with α-fucosidase. The degradations of the virus glycopeptides proceeded in the same way as stepwise digestions of reference glycopeptides of the lactosamine type obtained from IgG and α1-acid glycoprotein. This suggests that all three membrane glycoproteins of Semliki Forest virus contained glycans with a monosaccharide sequence characteristic for lactosamine type oligosaccharides. The number of both distal and proximal N-acetyl-glucosamine residues was estimated to be usually two. According to exo- and endo-glycosidase digestions, fucose seemed to be attached to the innermost N-acetyl-glucosamine unit.

Two independently derived cell lines which carry the herpes simplex type 2 thymidine kinase gene have been examined for the presence of HSV-2-specific DNA sequences. Both cell lines contained 1 to 3 copies per cell of a sequence lying within map co-ordinates 0.2 to 0.4 of the HSV-2 genome. Revertant cells, which contained no detectable thymidine kinase, did not contain this DNA sequence. The failure of EcoR1-restricted HSV-2 DNA to act as a donor of the thymidine kinase gene in transformation experiments suggests that the gene lies close to the EcoR1 restriction site within this sequence at a map position of approx. 0.3. The HSV-2 kinase gene is therefore approximately co-linear with the HSV-1 gene.

The RNA-dependent RNA polymerase induced in BHK 21 cells by infection with foot-and-mouth disease virus has been isolated from the replication complex. It contains a major, virus-coded protein with mol. wt. 56000 which appears from serological studies and tryptic peptide mapping to be the same as the virus infection associated (VIA) antigen and the protein P56 found in cells infected with the virus. Other virus coded proteins and a host cell protein were present in the partially purified replication complex but were removed by digestion with ribonuclease T1, leaving only the major virus coded protein. The tryptic peptide maps of the VIA antigen of the seven serotypes of the virus were similar, suggesting a high level of conservation in that region of the genome coding for the RNA polymerase of each type.

Electron microscopy of hepatitis B antigen has revealed Dane particles with abnormal morphology. These aberrant Dane particles contain incomplete cores. They were seen in large numbers in the serum of an HBsAg-carrying renal dialysis patient and were less numerous but invariably present in other Dane particle-containing sera — 12 from asymptomatic carriers, 2 chronic hepatitis patients and 1 patient with acute hepatitis. All 16 sera were shown to contain HBeAg.

The capsid of Bacillus subtilis bacteriophage SP3 is assembled via a prohead intermediate which subsequently encapsulates DNA and attaches a tail. The prohead contains a ring-like core structure. The spokes which extend from the core to the inner prohead surface are thought to form a scaffold for the polymerization of the prohead. Ninety percent of the proheads are assembled prior to the onset of DNA encapsulation. The first mature phage particles are observed at 45 min after infection; titres of intracellular phage demonstrate their infectivity. The core is visible in phage ghosts.

Adenovirus DNA-protein complex purified by sedimentation on a sucrose gradient containing 4 m-guanidine hydrochloride was found to contain other virion proteins in addition to the terminal protein of mol. wt. 55000. In this report, we describe a simple and rapid method for the isolation of a homogeneous DNA-protein complex. The procedure involves gel electrophoresis of the complex on agarose in the presence of sodium dodecyl sulphate. DNA was found to migrate into the gel with a single protein of mol. wt. 55000 tightly attached to it. Restriction enzyme cleavage analysis of the DNA-protein complex shows that the protein is associated with the two terminal fragments.

Newly synthesized nuclear NP, M and NS1 proteins migrated from the nucleus over a period of several hours. Rates of transport were higher for NP than for M or NS1 and suggest that nuclear NP may play a role in multiplication.

An immune electron microscopic technique for detecting plant viruses is described which involves pre-coating electron microscope grids with protein A (a wall protein of Staphylococcus aureus) before coating them with specific anti-serum. The method trapped 339 and 51 times more sugarcane mosaic virus and tobacco mosaic virus particles, respectively, than untreated grids. It appears particularly suitable for virus particles occurring in plant extracts in small numbers.