Myoglobin or the Biologist's Hydrogen Atom: Towards Detailed Understanding

Prof. Markus Meuwly
School of Chemistry
University of Basel

The literature on the binding, photodissociation and rebinding of small ligands (dioxygen, nitric oxide, carbon monoxide) with myoglobin (Mb) is extensive. This is due to the importance of myoglobin as both a protein in its own right, and as a model system for the study of proteins in general. Despite the wealth of experimental and theoretical information available, a microscopic understanding of ligand binding is elusive and fundamental questions remain unanswered. Where does the free ligand go following photodissociation? What are the time scales for ligand motion? What is the origin of energy barriers to rebinding? Some of these questions are only now starting to being answered. Molecular dynamics simulations and their significance in view of recent experiments relevant to these questions are discussed.