title: Biophysical study of thermal denaturation of apo-calmodulin: dynamics of native and unfolded states.
abstract: Apo-calmodulin, a small, mainly alpha, soluble protein is a calcium-dependent protein activator. This article presents a study of internal dynamics of native and thermal unfolded apo-calmodulin, using quasi-elastic neutron scattering. This technique can probe protein internal dynamics in the picosecond timescale and in the nanometer length-scale. It appears that a dynamical transition is associated with thermal denaturation of apo-calmodulin. This dynamical transition goes together with a decrease of the confinement of hydrogen atoms, a decrease of immobile protons proportion and an increase of dynamical heterogeneity. The comparison of native and unfolded states dynamics suggests that the dynamics of protein atoms is more influenced by their distance to the backbone than by their solvent exposure.
authors.affiliation: Laboratoire Léon Brillouin, Centre National de la Recherche Scientifique, Saclay, France. gabriel.gibrat@cea.fr
authors.forename: Gabriel
authors.initials: G
authors.lastname: Gibrat
authors.forename: France Liliane
authors.initials: FL
authors.lastname: Assairi
authors.forename: Yves
authors.initials: Y
authors.lastname: Blouquit
authors.forename: Constantin T
authors.initials: CT
authors.lastname: Craescu
authors.forename: Marie-Claire
authors.initials: MC
authors.lastname: Bellissent-Funel
mesh_terms: D002147:Calmodulin / Q000737:chemistry / Q000378:metabolism*; D004548:Elasticity; D006801:Humans; D009068:Movement; D033363:Neutron Diffraction; D011489:Protein Denaturation; D017510:Protein Folding; D044366:Transition Temperature
chemical_list: D002147:Calmodulin