Electronic and Structural Heterogeneity in the Diiron Center of Sulerythrin: Insights From Hybrid QM/MM Calculations.

ABSTRACT: Sulerythrins (SulE) are ferritin-like proteins from obligate aerobes such as Sulfolobus tokodaii, forming a domain-swapped dimer with a four-helix-bundle scaffold and a heterobimetallic Fe-Zn center. The diFe-SulE variant resembles diiron carboxylate proteins and contains two bimetallic active sites coordinated by histidines, glutamates, and bridging oxo ligands. High-resolution crystallography revealed slight differences in Fe-Fe distances and mixed-valence states, but the precise chemical nature of the oxo species remains unclear. To clarify the electronic and structural properties of diFe-SulE, we performed hybrid quantum mechanical/molecular mechanics (QM/MM) calculations on models varying in protonation, dioxo ligands, and iron redox states of the active site. Our results reveal at le

SUBMITTER: Moubarak S 

PROVIDER: S-EPMC12833474 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature