title: Identification of strains of herpes simplex virus by comparison of the density of their DNA using the preparative ultracentrifuge.
abstract: The buoyant densities of the DNA of herpes simplex virus type 1, type 2 and Pseudorabies virus, as determined in the analytical ultracentrifuge, are 1.725, 1.727 and 1.731 correlating with G+C contents of 67, 69 and 73 per cent respectively. The density differences for the DNA's of type 1 and type 2 herpes simplex viruses have been confirmed in experiments with isotopically labelled DNA from four type 1 and six type 2 strains by preparative CsCl gradient ultracentrifugation. The DNA of all the type 2 strains was denser than that of any of the type 1 strains examined. Despite these differences in DNA base composition of type 1 and type 2 strains, nearest neighbour analysis of their DNA's disclosed no obvious differences in doublet pattern or general design.
mesh_terms: D001483:Base Sequence; D002499:Centrifugation, Density Gradient; D002500:Centrifugation, Isopycnic; D003596:Cytosine / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis*; D006147:Guanine / Q000032:analysis; D018139:Simplexvirus / Q000032:analysis / Q000145:classification*; D013045:Species Specificity
chemical_list: D004279:DNA, Viral; D006147:Guanine; D003596:Cytosine