Thermal unfolding of the archaeal DNA and RNA binding protein Ssh10
2008 (English)In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 373, no 4, 482-487 p.Article in journal (Refereed) PublishedText
The reversible thermal unfolding of the archaeal histone-like protein Ssh10b from the extremophile Sulfolobus shibatae was studied using differential scanning calorimetry and circular dichroism spectroscopy. Analytical ultracentrifugation and gel filtration showed that Ssh10b is a stable dimer in the pH range 2.5-7.0. Thermal denaturation data fit into a two-state unfolding model, suggesting that the Ssh10 dimer unfolds as a single cooperative unit with a maximal melting temperature of 99.9 degrees C and an enthalpy change of 134 kcal/mol at pH 7.0. The heat capacity change upon unfolding determined from linear fits of the temperature dependence of DeltaH(cal) is 2.55 kcal/(mol K). The low specific heat capacity change of 13 cal/(mol K residue) leads to a considerable flattening of the protein stability curve (DeltaG (T)) and results in a maximal DeltaG of only 9.5 kcal/mol at 320 K and a DeltaG of only 6.0 kcal/mol at the optimal growth temperature of Sulfolobus.
Place, publisher, year, edition, pages
2008. Vol. 373, no 4, 482-487 p.
*Hot Temperature, Amino Acid Sequence, Archaeal Proteins/chemistry/*metabolism, Calorimetry, Differential Scanning, Circular Dichroism, DNA-Binding Proteins/chemistry/*metabolism, Histones/chemistry/*metabolism, Hydrogen-Ion Concentration, Molecular Sequence Data, Protein Denaturation, Protein Folding, RNA-Binding Proteins/chemistry/*metabolism, Sulfolobus/*metabolism, Thermodynamics
Biochemistry and Molecular Biology
Research subject Other research area
IdentifiersURN: urn:nbn:se:sh:diva-29045DOI: 10.1016/j.bbrc.2008.06.030ISI: 000258208500006PubMedID: 18571501ScopusID: 2-s2.0-48949115342OAI: oai:DiVA.org:sh-29045DiVA: diva2:891546
Wu, Xiaoqiu Oppermann, Madalina Berndt, Kurt D Bergman, Tomas Jornvall, Hans Knapp, Stefan Oppermann, Udo Research Support, Non-U.S. Gov't United States Biochemical and biophysical research communications Biochem Biophys Res Commun. 2008 Sep 5;373(4):482-7. Epub 2008 Jun 20.2016-01-072016-01-072016-01-11Bibliographically approved