The coat proteins of cauliflower mosaic virus.

Four polypeptides with molecular weights and molar ratios (in parentheses) of 96,000 and 88,000 (both 0.08), 64,000 (0.15) and 37,000 (0.77) were found in purified preparations of cauliflower mosaic virus (CaMV). Two further polypeptides were found in some preparations and one was shown to be a degradation product of the major polypeptide. The four proteins found consistently had uniform charge/size ratio and gave positive but faint reaction to periodate-Schiff stain for glycoprotein. It is proposed that CaMV particles are composed of a T = 7 shell of the major protein surrounding a T = 1 core of the 64,000 molecular weight protein.