Tryptophan Residues as Membrane Protein Anchors

Tryptophan is unique among the natural amino acids; for example, it exhibits the largest accessible nonpolar surface area, has the greatest ionization potential, possesses an indole N-H moiety for hydrogen bond donation, and displays the greatest electrostatic potential for cation-pi interactions. These important chemical properties render tryptophan an important functional residue in diverse biological systems. Our group utilizes resonance Raman and electronic spectroscopy to probe the photophysical, photochemical, and structural properties of tryptophan in two broad themes in biology: electron transfer chemistry and membrane proteins. Here, we focus on the topic of membrane protein folding and membrane-associated peptides.