%0 Journal Article %A Adolph, K. W. %T Structural Transitions of Cowpea Chlorotic Mottle Virus %D 1975 %J Journal of General Virology, %V 28 %N 1 %P 147-154 %@ 1465-2099 %R https://doi.org/10.1099/0022-1317-28-1-147 %I Microbiology Society, %X SUMMARY Particles of cowpea chlorotic mottle virus (CCMV) underwent an abrupt structural transition as the pH was raised to near pH 6.75. At low ionic strength (I = 0.2) the transition was observed as a decrease from 83S to 73S in the sedimentation coefficient of the virus particle. At high ionic strength (I = 1.0) the virus disassembled to components sedimenting at about 40S. These observations suggest a structural role for the RNA in maintaining virus stability. As ionic strength at pH 7.5 was increased, a critical point was reached (I = 0.4) at which the virus disassembled to the 40S aggregates. The effect of raising the temperature of both unswollen and swollen virus was to gradually, but substantially, reduce the sedimentation coefficient. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-28-1-147