CONFORMATION CHANGES IN CAULIFLOWER MOSAIC VIRUS

Incubation of cauliflower mosaic virus (CAMV) in 1% sodium dodecyl sulfate (SDS) for 10 min at 50-70° resulted in the conversion of 206 S CAMV to slower-sedimenting particles of 190 S, 150 S, and 110 S. Slower-sedimenting particles did not show appreciable loss of protein or nucleic acid and, by dialysis against phosphate buffer, reversed to particles sedimenting at the same rate as the original CAMV particles, suggesting that 206 S-190 S-150 S-110 S conversions are reversible. CAMV seems to convert into expanded or loosened particles and at last into free nucleic acid and protein by SDS-heat treatment. © 1969.