Propagation of Photoinduced Electric Field Changes Through Phytochrome and their Impact on Conformational Transitions.

ABSTRACT: In phytochromes, photoisomerization of the chromophore and subsequent structural relaxations lead to the functionally essential secondary structure transition of the tongue, a phytochrome-specific protein segment. The coupling mechanism between chromophore and protein structural changes is yet not understood, but electric field changes are discussed to play an important role. In this work, electric field changes in the chromophore binding pocket (CBP) are confirmed to propagate over long distances through the protein and alter the electric field in the tongue region. An experimental-theoretical approach to analyze local electric fields using Stark reporters has been further developed. These are nitrile groups introduced site-specifically into the protein via noncanonical amino acids. The f

SUBMITTER: La Greca M 

PROVIDER: S-EPMC12640670 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature