Structural Basis for Blocked Excited State Proton Transfer in a Fluorescent, Photoacidic Non-Canonical Amino Acid-Containing Antibody Fragment.

ABSTRACT: The fluorescent non-canonical amino acid (fNCAA) L-(7-hydroxycoumarin-4-yl)ethylglycine (7-HCAA) contains a photoacidic 7-hydroxycoumarin (7-HC) side chain whose fluorescence properties can be tuned by its environment. In proteins, many alterations to 7-HCAA's fluorescence spectra have been reported including increases and decreases in intensity and red- and blue-shifted emission maxima. The ability to rationally design protein environments that alter 7-HCAA's fluorescence properties in predictable ways could lead to novel protein-based sensors of biological function. However, these efforts are likely limited by a lack of structural characterization of 7-HCAA-containing proteins. Here, we report the steady-state spectroscopic and x-ray crystallographic characterization of a 7-HCAA-containi

SUBMITTER: Henderson JN 

PROVIDER: S-EPMC9018508 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature