ABSTRACT
DNA preparations from nuclear polyhedrosis virus (NPV) of Galleria mellonella L. (GmL) were fractionated in high ionic strength neutral sucrose gradient. This procedure allowed a separation of supercoiled infectious DNA molecules with contour length of 48--52 microns from infectious open ring DNA molecule, and noninfectious linear DNA molecules of the same size. In addition a heterogeneity of supercoiled DNA molecules was detected. Covalently closed DNA molecules did not contain protein or ribonucleotide ligands which could be digested by pronase or pancreatic RNase treatment. It is concluded from data on the infectivity of different molecular forms of DNA and reassociation kinetics studies, that the genome of GmL NPV is a unique ring nucleotide sequence with a molecular weight of about 90--100 X 10(6).
Subject(s)
DNA, Viral/analysis , Insect Viruses/ultrastructure , Lepidoptera/microbiology , Moths/microbiology , Nucleic Acid Conformation , Animals , DNA, Circular/analysis , DNA, Superhelical/analysis , Hot Temperature , Microscopy, Electron , Molecular Weight , Nucleic Acid Denaturation , Nucleotides/analysisABSTRACT
Free Galleria mellonella nuclear polyhedrosis virus was purified 4000--4500 times by Tween-80 treatment and repeated sucrose density gradient centrifugation, based on the ratio of infectivity to protein content as compared to the starting virus-containing suspension.
