"Employing Unnatural Amino Acids to Sense Local Protein Environments and Alter Protein Functions"
Unnatural amino acids (UAAs) expand the landscape of protein biochemistry, providing new tools to examine and tune protein structure and function. Using the amber codon suppression technology these UAAs can be site-specifically incorporated into proteins. The UAA 4-cyano-Lphenylalanine (pCNF) contains the nitrile functional group whose nitrile stretching frequency is located both in a quiet region of protein IR spectra and is sensitive to local environment. Our work using pCNF site-specifically incorporated at various locations in both the gas-sensing Heme Nitric Oxide and/or Oxygen (H-NOX) binding protein from Caldanaerobacter subterraneus and the super folder Green Fluorescent Protein (sfGFP) will be discussed. In addition, work towards modifying the protein functions of H-NOX and sfGFP using modified phenylalanine UAAs will also be presented.