Peptides in motion

The control of biological processes has always been a challenge for chemists and biochemists. The ability to interfere with a specific biological function helps scientists to achieve a better understanding of the process itself and, if the process is correlated with pathology, it might be possible to gain new insights in the development of diseases and eventually to discover new treatments. Towards this goal, the control of biological processes can be established using light as a stimulus. The advantages of light are that it is not invasive and usually, bioorthogonal: it does not interfere with almost any biological function. Light-control of biological functions can be addressed using photoswitches that are molecules that change conformation upon irradiation with light.
In this thesis, the structure of these photoswitchable molecules and the strategies to incorporate them into peptides are described. Illustrative examples of photoswitchable peptides are highlighted, with special focus on peptidic domains, including photosensitive β-hairpins and zinc-fingers.
The results presented in this thesis aim at establishing new methods for modification of peptides, enzymes and proteins with photoswitches. In particular, an overcrowded alkene switch is inserted for the first time in peptides. Ultimately, this work may provide tools for modification of photosensible surfaces with biomolecules and for constructing new photoresponsive biosystems.