Thermal stability of cowpea mosaic virus components: differential scanning calorimetry studies.

Differential scanning calorimetry studies show that the thermal stability of cowpea mosaic virus (CPMV) is pH dependent in the pH range 5 to 8. The four different components of CPMV, top (protein shell devoid of RNA), middle (virus particle containing the smaller RNA), bottom upper and bottom lower (virus particle containing the larger RNA), are stable up to 64-70 degrees at pH 5.0 and up to 43-46 degrees at pH 8.25. These components did not exhibit any difference in their thermal stability between pH 6.0 and 8.0.