The role of the denatured state in protein folding represents a key issue for the proper evaluation of folding kinetics and mechanisms. The yeast ortholog of the human frataxin, a mitochondrial protein essential for iron homeostasis and responsible for Friedreich's ataxia, has been shown to undergo cold denaturation above 0 °C, in the absence of chemical denaturants. This interesting property provides the unique opportunity to explore experimentally the molecular mechanism of both the hot and cold denaturation. In this work, we present the characterization of the temperature and urea dependence of the folding kinetics of yeast frataxin, and show that while at neutral pH and in the absence of a denaturant a simple two-state model may satisfactorily describe the temperature dependence of the folding and unfolding rate constants, the results obtained in urea over a wide range of pH reveal an intriguing complexity, suggesting that folding of frataxin involves a broad smooth free energy barrier. © 2014 the Partner Organisations.

The kinetics of folding of frataxin

Pastore Annalisa;
2014

Abstract

The role of the denatured state in protein folding represents a key issue for the proper evaluation of folding kinetics and mechanisms. The yeast ortholog of the human frataxin, a mitochondrial protein essential for iron homeostasis and responsible for Friedreich's ataxia, has been shown to undergo cold denaturation above 0 °C, in the absence of chemical denaturants. This interesting property provides the unique opportunity to explore experimentally the molecular mechanism of both the hot and cold denaturation. In this work, we present the characterization of the temperature and urea dependence of the folding kinetics of yeast frataxin, and show that while at neutral pH and in the absence of a denaturant a simple two-state model may satisfactorily describe the temperature dependence of the folding and unfolding rate constants, the results obtained in urea over a wide range of pH reveal an intriguing complexity, suggesting that folding of frataxin involves a broad smooth free energy barrier. © 2014 the Partner Organisations.
2014
Settore BIO/11 - Biologia Molecolare
Hydrogen-Ion Concentration; Iron-Binding Proteins; Kinetics; Protein Structure; Tertiary; Protein Unfolding; Recombinant Proteins; Saccharomyces cerevisiae; Temperature; Thermodynamics; Urea; Physical and Theoretical Chemistry; Physics and Astronomy (all)
File in questo prodotto:
File Dimensione Formato  
c3cp54055c.pdf

Accesso chiuso

Tipologia: Published version
Licenza: Non pubblico
Dimensione 1.27 MB
Formato Adobe PDF
1.27 MB Adobe PDF   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11384/77124
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 17
  • ???jsp.display-item.citation.isi??? 15
  • OpenAlex ND
social impact