Capsid and Procapsid Proteins of a Bovine Enterovirus

A bovine enterovirus (serotype VG-5-27) was grown in BHK 21 cells and purified using gel filtration and sedimentation procedures. Infective particles sedimented at 165s and the empty capsids or procapsids at 75s. Proteins extracted from each type of component were separated by polyacrylamide-gel electrophoresis. The infective component yielded four polypeptides of molecular weight 34,000, 28,000, 26,000 and 9,000 and were present in molar ratios of 1:1:1:0.5, respectively. Three polypeptides were extracted from the procapsid. These have molecular weights 37,000, 34,000 and 26,000 and were present in molar ratios of 1:1:1, respectively. We interpret these results as indicating that the small polypeptide of the virus particle may have a specific location in the virus in relation to the three major structural proteins.