Function and Dynamics of Myoglobin a

After a lecture on atoms and molecules a t the Leopoldina Academy, a listener asked: “Can atoms be sick?” Obviously, the answer is no. All atoms of a given element and isotope are exactly alike. Proteins, however, can be sick. The replacement of one amino acid by another one may have disastrous consequences. Biomolecular medicine and pharmacology consequently are important. The entire field is so enormous and the number of possibilities for modification of even a small protein is so incredibly large that tinkering is of very limited value. What we need is a profound understanding of the function and dynamics of biomolecules as one of the essential components for a theoretical medicine. We take the approach of experimental physics to this difficult problem: We select a simple protein (myoglobin), study a simple process (binding of dioxygen and carbon monoxide), construct simple models, and try to fit and explain the data over wide ranges in time, temperature, pressure, and other external conditions. The goal of this approach is the discovery of general concepts and principles that can then also be applied to other systems. The road from such primitive studies to clinical applications is long, but it may well be one that ultimately pays off in a deeper understanding. In the present contribution, I will describe the central concepts that have emerged. The experimental underpinning will only be sketched in a few places; the details can be found in the references.

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