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. 1974 Aug;1(8):945–958. doi: 10.1093/nar/1.8.945

Urea perturbation and the reversibility of nucleohistone conformation

Catherine Chang 1, Hsueh Jei Li 1
PMCID: PMC343403  PMID: 10793727

Abstract

Urea effect on conformation and thermal stabilities in nucleohistone and NaCl-treated partially dehistonized nucleohistones has been studied by circular dichroism (CD) and thermal denaturation. Urea imposes a CD change at 278mm of DNA base pairs in native and NaCl-treated nucleohistones which can be decomposed into two parts: a decrease in Δε278 for histone-free base pairs and an increase for histone-bound base pairs. The reduction by urea of Δε220 of bound histones is approximately proportional to the increase of Δε278 of histone-bound base pairs. Urea also lowers the melting temperatures of base pairs both free and bound by histones. The presence of urea indeed destroys the secondary structure of bound histones, causing changes in the conformation and thermal stabilities of histone-bound base pairs in nucleohistone. Such a urea perturbation on nucleohistone conformation is reversible.

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Selected References

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

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