Mechanism of Color and Photoacidity Tuning for the Protonated Green Fluorescent Protein Chromophore.

ABSTRACT: The neutral or A state of the green fluorescent protein (GFP) chromophore is a remarkable example of a photoacid naturally embedded in the protein environment and accounts for the large Stokes shift of GFP in response to near UV excitation. Its color tuning mechanism has been largely overlooked, as it is less preferred for imaging applications than the redder anionic or B state. Past studies, based on site-directed mutagenesis or solvatochromism of the isolated chromophore, have concluded that its color tuning range is much narrower than its anionic counterpart. However, as we performed extensive investigation on more GFP mutants, we found that the color of the neutral chromophore can be more sensitive to protein electrostatics than can the anionic counterpart. Electronic Stark spectroscop

SUBMITTER: Lin CY 

PROVIDER: S-EPMC7485587 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature