Characterization of the Kilham Rat Virus

Abstract

Kilham rat virus (KRV) was found to grow in a rat nephroma cell line and to form plaques on secondary rat embryo monolayers. The virus was purified by enzymatic treatment and isopycnic cesium chloride sedimentation. KRV bands at a density of 1.41 g/cm3 in cesium chloride. It contains about 26.5% deoxyribonucleic acid (DNA). The sedimentation coefficient S2o, in sucrose gradients was 122 corresponding to a molecular weight of 6.6 X 106 daltons. The reaction of formaldehyde with the KRV virion suggests that the DNA in situ is single-stranded. DNA extracted from KRV had a buoyant density of 1.715 g/cm' in cesium chloride. The S20,W was determined in sucrose gradients to be 16, and the molecular weight was calculated to be approximately 1.7 x 106 daltons. The base composition of the DNA is 26.7% adenine, 30.8% thymine, 20.0% guanine, and 22.5% cytosine. On the basis of its noncomplementary nucleotide ratio, melting curve, and the reaction with formaldehyde, the DNA of KRV is believed to be single-stranded.

Human lymphoblastoid cells as hosts for parvoviruses H-1 and rat virus

“…RV was radioactively labeled with [methyl-3H]thymidine (3H-RV) by the method of Salzman and Jori (17). Viral hemagglutinin was detected by a microtiter hemagglutination (HA) test, using equal volumes (0.05 ml) of the virus sample and of a 0.5% suspension of guinea pig erythrocytes.…”

Structural Proteins of Adenovirus-Associated Viruses

“…The adenovirus-associated viruses (AAV) are small, deoxyribonucleic acid (DNA)-containing animal viruses whose size and physical properties resemble those of other members of the parvovirus group (1,4,7,19,22). The AAV differ, however, from other parvoviruses in two distinctive ways.…”

“…The single-stranded AAV genome has a molecular weight of 1.5 x 106 to 1.7 x 106 daltons (15,19,21) and is approximately 112 as large as the double-stranded adenovirus genome. Although AAV are defective, AAV DNA is similar in size to DNA from other parvoviruses (4,22). These genomes are among the smallest and least complex of all animal virus genomes and, based on molecular weight, would be expected to specify as few as 4 to 8 proteins.…”

Certain physico-chemical properties of mosquito densonucleosis virus DNA

“…Наблюдаемое в опытах увеличение поглощения (260 им) при взаимодействии вирионов с формальдегидом известно и для других парвовирусов. Так, гиперхромизм парвовируса крыс при взаимодействии с формальдегидом составляет 13-16% [18], мелкого вируса мышей -18% [19]. У ДНК ВДК большой вощинной моли в среде с низкой ионной силой ои составляет 12 % [20].…”