Titelangaben
Mayr, Lorenz M. ; Schmid, Franz X.:
Stabilization of a protein by guanidinium chloride.
In: Biochemistry.
Bd. 32
(1993)
Heft 31
.
- S. 7994-7998.
ISSN 1520-4995
DOI: https://doi.org/10.1021/bi00082a021
Abstract
Guanidinium chloride is a commonly used denaturant to unfold native proteins and to determine their Gibbs free energy of stabilization, delta Gstab. Here we show that this denaturant has a dual role for the stability and the folding of the model protein ribonuclease T1. When present at low concentration (0-0.3 M), guanidinium chloride stabilizes the folded protein toward thermal and urea-induced unfolding and decreases the rate of unfolding. At high concentration the function of guanidinium chloride as a denaturant dominates and ribonuclease T1 is cooperatively unfolded. Ribonuclease T1 is also strongly stabilized by other salts, such as NaCl, at low concentrations, and the dependence of the thermal stability on salt concentration is not linear. Such a complex behavior was not found in control experiments with pancreatic ribonuclease A. The stabilization in the presence of low concentrations of guanidinium chloride originates probably from the binding of guanidinium ions to one or a few cation binding sites that exist in native ribonuclease T1. It is not observed when an additional salt, NaCl, is present simultaneously. The favorable interaction of guanidinium chloride with the native protein leads to increased values for delta Gstab, when unfolding transitions induced by guanidinium chloride are analyzed on the basis of the two-state model by the linear extrapolation procedure. The noncoincidence of these delta Gstab values with stability data derived from urea-induced or thermal unfolding transitions does not imply that the two-state model is not appropriate but that the linear extrapolation to zero molar denaturant is incorrect.(ABSTRACT TRUNCATED AT 250 WORDS)
Weitere Angaben
Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | PubMed-ID: 8347603 |
Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Ehemalige Professoren > Professur Biochemie - Univ.-Prof. Dr. Franz Xaver Schmid Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Professur Biochemie Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Ehemalige Professoren |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik > 540 Chemie |
Eingestellt am: | 15 Mai 2015 05:37 |
Letzte Änderung: | 20 Apr 2022 12:11 |
URI: | https://eref.uni-bayreuth.de/id/eprint/13469 |