title: Energy landscape in protein folding and unfolding.
abstract: We use (1)H NMR to probe the energy landscape in the protein folding and unfolding process. Using the scheme ⇄ reversible unfolded (intermediate) → irreversible unfolded (denatured) state, we study the thermal denaturation of hydrated lysozyme that occurs when the temperature is increased. Using thermal cycles in the range 295 < T < 365 K and following different trajectories along the protein energy surface, we observe that the hydrophilic (the amide NH) and hydrophobic (methyl CH3 and methine CH) peptide groups evolve and exhibit different behaviors. We also discuss the role of water and hydrogen bonding in the protein configurational stability.
authors.affiliation: CNR-Istituto per i Processi Chimico Fisici Messina, I-98166 Messina, Italy; Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139; Center for Polymer Studies and Department of Physics, Boston University, Boston, MA 02215; francesco.mallamace@unime.it hes@bu.edu.
authors.forename: Francesco
authors.initials: F
authors.lastname: Mallamace
authors.affiliation: CNR-Istituto per i Processi Chimico Fisici Messina, I-98166 Messina, Italy; Dipartimento di Fisica e di Scienze della Terra, Università di Messina, I-98166 Messina, Italy;
authors.forename: Carmelo
authors.initials: C
authors.lastname: Corsaro
authors.affiliation: Consorzio per lo Sviluppo dei Sistemi a Grande Interfase, Unità di Catania, I-95125 Catania, Italy;
authors.forename: Domenico
authors.initials: D
authors.lastname: Mallamace
authors.affiliation: Dipartimento di Fisica e di Scienze della Terra, Università di Messina, I-98166 Messina, Italy;
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Vasi
authors.affiliation: CNR-Istituto per i Processi Chimico Fisici Messina, I-98166 Messina, Italy;
authors.forename: Cirino
authors.initials: C
authors.lastname: Vasi
authors.affiliation: Dipartimento di Chimica, Università di Firenze and Consorzio per lo Sviluppo dei Sistemi a Grande Interfase, I-50019 Florence, Italy;
authors.forename: Piero
authors.initials: P
authors.lastname: Baglioni
authors.affiliation: Department of Physics, Yeshiva University, New York, NY 10033.
authors.forename: Sergey V
authors.initials: SV
authors.lastname: Buldyrev
authors.affiliation: Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139;
authors.forename: Sow-Hsin
authors.initials: SH
authors.lastname: Chen
authors.affiliation: Center for Polymer Studies and Department of Physics, Boston University, Boston, MA 02215; francesco.mallamace@unime.it hes@bu.edu.
authors.forename: H Eugene
authors.initials: HE
authors.lastname: Stanley
mesh_terms: D009113:Muramidase / Q000737:chemistry; D011489:Protein Denaturation; D017510:Protein Folding; D066244:Proton Magnetic Resonance Spectroscopy; D013696:Temperature
chemical_list: D009113:Muramidase
keywords: energy landscape; hydration water; protein folding; proton NMR