Investigating the interaction of azobenzene moiety on the amino acid tryptophan

Molecular photoswitches are a series of compounds that can be isomerized upon irradiation with light. Photoswitchable molecules can modify the physical, chemical, and biological properties of a diverse range of materials. They can control protein structure and function with temporal and spatial precision. In this work, we investigated the possible interaction between azobenzene and aromatic amino acids. We hypothesized that aromatic amino acids, such as tryptophan, would show altered photochemical properties when conjugated with azobenzene. When irradiated at either 365 nm or 465 nm, the photo-switching behavior favors the cis isomer and is visibly fluorescent at 365 nm. To our knowledge, this is the first evidence to suggest that primary protein structure could affect photoswitch activity. The knowledge gained from this research will help to further the understanding of photoswitches as they are used in biomolecules.