Switching the proton-coupled electron transfer mechanism for non-canonical tyrosine residues in a de novo protein.

ABSTRACT: The proton-coupled electron transfer (PCET) reactions of tyrosine (Y) are instrumental to many redox reactions in nature. This study investigates how the local environment and the thermodynamic properties of Y influence its PCET characteristics. Herein, 2- and 4-mercaptophenol (MP) are placed in the well-folded α₃C protein (forming 2MP-α₃C and 4MP-α₃C) and oxidized by external light-generated [Ru(L)₃]³⁺ complexes. The resulting neutral radicals are long-lived (>100 s) with distinct optical and EPR spectra. Calculated spin-density distributions are similar to canonical Y˙ and display very little spin on the S-S bridge that ligates the MPs to C₃₂ inside the protein. With 2MP-α₃C and 4MP-α₃C we probe how p

SUBMITTER: Nilsen-Moe A 

PROVIDER: S-EPMC10935721 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature