Structural Heterogeneity in a Phototransformable Fluorescent Protein Impacts its Photochemical Properties.

ABSTRACT: Photoconvertible fluorescent proteins (PCFP) are important cellular markers in advanced imaging modalities such as photoactivatable localization microscopy (PALM). However, their complex photophysical and photochemical behavior hampers applications such as quantitative and single-particle-tracking PALM. This work employs multidimensional NMR combined with ensemble fluorescence measurements to show that the popular mEos4b in its Green state populates two conformations (A and B), differing in side-chain protonation of the conserved residues E212 and H62,  altering the hydrogen-bond network in the chromophore pocket. The interconversion (protonation/deprotonation) between these two states, which occurs on the minutes time scale in the dark, becomes strongly accelerated in the presence of UV l

SUBMITTER: Maity A 

PROVIDER: S-EPMC10933604 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature