Processus ultra-rapides dans les hémoprotéines

Heme proteins contribute to a large variety of biological functions including transport and storage of oxygen, catalysis, electron transfer and signalling. The iron atom in the heme can bind amino acids and also diatomic molecules (O₂, NO, CO). These bonds can efficiently be broken by a light pulse. Using ultrafast optical spectroscopy techniques, this property allows the study of structural and electronic dynamics in the heme and its proteic environment at femtosecond-picosecond time scales, i.e. at the time scale of internal vibrations of the macromolecular systems. This review describes recent progress in this domain, specifically the role of concerted movements of the heme-protein system in ballistic ligand transfer reactions as well as the real-time monitoring of signal propagation within signalling proteins. Heme proteins, femtosecond spectroscopy, molecular dynamics, ligand.