[Biological and physicochemical properties of virus PBV-1, isolated from Penicillium brevi compactum]

High infectivity of PBV-1 virus for different strains of E. coli has been demonstrated. Sizes of the virus particle are; head diameter 513 angstrom, length of the process 1500 angstrom, diameter of the process 60 angstrom. The buoyant density of the virus in cesium chloride density gradient is 1.49 g/cm3, in cesium sulphate-1.39 g/cm3, the sedimentation constant of the virus particle is 380S; molecular weight is 52.8 plus or minus 1.9 times 10-6 daltons. The PBV-1 virus contains double-stranded DNA with the melting temperature in 1 SSC (0.15 M NaCl plus 0.0015 M sodium citrate, pH 7.0) and in 0.1 SSC-88.5 degrees C, respectively. The buoyant density of DNA in cesium chloride gradient is 1.7058 g/cm3 and in cesium sulphate 1.424 g/cm3. The content of GC-pairs calculated by the melting temperature is 46.5% and by the buoyant density 46.7%. On the basis of DNA sedimentation constant value (30S) the average molecular weight of DNA has been calculated to be 23.7 times 10-6 daltons.