Visualizing Biological Copper Storage: The Importance of Thiolate-Coordinated Tetranuclear Clusters.

ABSTRACT: Bacteria possess cytosolic proteins (Csp3s) capable of binding large quantities of copper and preventing toxicity. Crystal structures of a Csp3 plus increasing amounts of Cu^I provide atomic-level information about how a storage protein loads with metal ions. Many more sites are occupied than Cu^I equiv added, with binding by twelve central sites dominating. These can form [Cu₄ (S-Cys)₄ ] intermediates leading to [Cu₄ (S-Cys)₅ ]^- , [Cu₄ (S-Cys)₆ ]^2- , and [Cu₄ (S-Cys)₅ (O-Asn)]^- clusters. Construction of the five Cu^I sites at the opening of the bundle lags behind the main core, and the two least accessible sites at the opposite end of the b

SUBMITTER: Basle A 

PROVIDER: S-EPMC5519932 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature