title: The role of hydration in protein stability: comparison of the cold and heat unfolded states of Yfh1.
abstract: Protein unfolding occurs at both low and high temperatures, although in most cases, only the high-temperature transition can be experimentally studied. A pressing question is how much the low- and high-temperature denatured states, although thermodynamically equivalent, are structurally and kinetically similar. We have combined experimental and computational approaches to compare the high- and low-temperature unfolded states of Yfh1, a natural protein that, at physiologic pH, undergoes cold and heat denaturation around 0 °C and 40 °C without the help of ad hoc destabilization. We observe that the two denatured states have similar but not identical residual secondary structures, different kinetics and compactness and a remarkably different degree of hydration. We use molecular dynamics simulations to rationalize the role of solvation and its effect on protein stability.
authors.affiliation: National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK.
authors.forename: Miquel
authors.initials: M
authors.lastname: Adrover
authors.forename: Gabriel
authors.initials: G
authors.lastname: Martorell
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Martin
authors.forename: Dunja
authors.initials: D
authors.lastname: Urosev
authors.forename: Petr V
authors.initials: PV
authors.lastname: Konarev
authors.forename: Dmitri I
authors.initials: DI
authors.lastname: Svergun
authors.forename: Xavier
authors.initials: X
authors.lastname: Daura
authors.forename: Pierandrea
authors.initials: P
authors.lastname: Temussi
authors.forename: Annalisa
authors.initials: A
authors.lastname: Pastore
mesh_terms: D000595:Amino Acid Sequence; D002942:Circular Dichroism; D003080:Cold Temperature; D006358:Hot Temperature; D033862:Iron-Binding Proteins / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D011487:Protein Conformation; D055550:Protein Stability; D058767:Protein Unfolding; D014867:Water / Q000737:chemistry; D000096923:Frataxin
chemical_list: D033862:Iron-Binding Proteins; D014867:Water; D000096923:Frataxin