Hydrogen Bonding and Noncovalent Electric Field Effects in the Photoconversion of a Phytochrome.

ABSTRACT: A profound understanding of protein structure and mechanism requires dedicated experimental and theoretical tools to elucidate electrostatic and hydrogen bonding interactions in proteins. In this work, we employed an approach to disentangle noncovalent and hydrogen-bonding electric field changes during the reaction cascade of a multidomain protein, i.e., the phytochrome Agp2. The approach exploits the spectroscopic properties of nitrile probes commonly used as reporter groups of the vibrational Stark effect. These probes were introduced into the protein through site-specific incorporation of noncanonical amino acids resulting in four variants with different positions and orientations of the nitrile groups. All substitutions left structures and the reaction mechanism unchanged. Structural m

SUBMITTER: Nguyen AD 

PROVIDER: S-EPMC11613453 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature