Mercury(II) Binding to Metallothionein in Mytilus edulis revealed by High Energy-Resolution XANES Spectroscopy.

ABSTRACT: Of all divalent metals, mercury (Hg^II ) has the highest affinity for metallothioneins. Hg^II is considered to be enclosed in the α and β domains as tetrahedral α-type Hg₄ Cys_11-12 and β-type Hg₃ Cys₉ clusters similar to Cd^II and Zn^II . However, neither the four-fold coordination of Hg nor the existence of Hg-Hg atomic pairs have ever been demonstrated, and the Hg^II partitioning among the two protein domains is unknown. Using high energy-resolution XANES spectroscopy, MP2 geometry optimization, and biochemical analysis, evidence for the coexistence of two-coordinate Hg-thiolate complex and four-coordinate Hg-thiolate cluster with a metacinnabar-type (β-HgS) structure in the α domain of separate

SUBMITTER: Manceau A 

PROVIDER: S-EPMC6582439 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature