Abstract
The nucleic acid of soybean chlorotic mottle virus (SoyCMV) was isolated and analysed. CsCl equilibrium density gradient centrifugation and thermal denaturation kinetics revealed that the nucleic acid is a double-stranded DNA. Electrophoresis in agarose gels separated SoyCMV DNA into multiple bands, similar to those of cauliflower mosaic virus (CaMV) DNA, which indicated that this DNA consisted of both linear and circular molecules. The existence of these different topological forms was confirmed by electron microscopy. Using six different restriction endonucleases a physical map was constructed which showed the SoyCMV genome to be a circular DNA molecule of approximately 8, 200 base pairs long. The results obtained support the previous assignment of SoyCMV to the caulimovirus group.
