ISSN:
1432-1017
Keywords:
Microcalorimetry
;
Thermodenaturation
;
Rod shaped viruses
;
Tobacco mosaic virus
;
Decapsidation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Physics
Notes:
Abstract The thermal denaturation of the common strain of a rod-shaped plant virus, tobacco mosaic virus, has been investigated by differential scanning calorimetry, and compared to that of various aggregation states of its coat protein and to that of three other TMV strains. The state of the virions was monitored by electron microscopy and analytical ultracentrifugation. The observed endotherms could be analysed in terms of a stepwise dissociation of the virions. The transition temperatures of the three successive structural changes increased with decreasing pH, from pH = 8.0 to pH = 5.0, although the corresponding enthalpy changes did not vary appreciably with pH. TMV-HR showed a stronger pH dependence of the transition temperatures than the other strains, probably reflecting the importance of the changes in affecting the charged amino acids of its coat protein. The first step of the dissociation, which correlates with the breaking up of the virions into three or four shorter rods, implies a conformational change of the particle that may be related to the first step of the in situ decapsidation of TMV
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00195447
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