Skip to main content
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1975 Sep;72(9):3501–3504. doi: 10.1073/pnas.72.9.3501

Quasi-elastic behavior of solutions of viral capsid and RNA at very low shearing stresses.

M G Hodgins, O C Hodgins, D W Kupke, J W Beams
PMCID: PMC433022  PMID: 1059137

Abstract

By the application of shearing stresses on the order of 10(-3) dyne cm-2 (10(-2) muN cm-2), via the magnetic viscodensimeter, extremely high relative viscosities (greater than 500) were observed when turnip yellow mosaic virus was degraded in alkali into its capsid and RNA. The solutions, however, possessed a watery consistency at this stage and exhibited a quasi-elastic character by rotor-recoil experiments. The development of this curious behavior was concentration and temperature dependent; it was not seen less than 0.5% nor at 8 degrees, and appeared sooner at 30 degrees than at 20 degrees. The time of appearance was delayed as the pH was lowered; however, the effect was still observed when the pH was as low as 9. Whereas reversibility was demonstrated when the shearing stresses exceeded the elastic resistance [0.17 dyne cm-2 (1.7 muN CM-2)], thorough mixing usually resulted in a normal behavior of the solutions thereafter. Values for the modulus of rigidity at 20 degrees for about 1% virus concentration was less than 2 X 10(-2) dyne cm-2 rad-1 (0.2 muN cm-2 rad-1), which, while extremely small, was reproducible. A porous structure, possibly involving a capsid and RNA complex, is envisioned.

Full text

PDF
3501

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aposhian H. V., Thayer R. E., Qasba P. K. Formation of nucleoprotein complexes between polyoma empty capsides and DNA. J Virol. 1975 Mar;15(3):645–653. doi: 10.1128/jvi.15.3.645-653.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. KAPER J. M. ALKALINE DEGRADATION OF TURNIP YELLOW MOSAIC VIRUS. I. THE CONTROLLED FORMATION OF EMPTY PROTEIN SHELLS. Biochemistry. 1964 Apr;3:486–493. doi: 10.1021/bi00892a004. [DOI] [PubMed] [Google Scholar]
  3. Kaper J. M., Siberg R. A. Degradation of turnip yellow mosaic virus by freezing and thawing in vitro: a new method for studies on the internal organization of the viral components and for isolating native RNA. Virology. 1969 Jul;38(3):407–413. doi: 10.1016/0042-6822(69)90153-6. [DOI] [PubMed] [Google Scholar]
  4. Kupke D. W., Hodgins M. G., Beams J. W. Simultaneous determination of viscosity and density of protein solutions by magnetic suspension. Proc Natl Acad Sci U S A. 1972 Aug;69(8):2258–2262. doi: 10.1073/pnas.69.8.2258. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES