Cu-specific CopB transporter: Revising P-type ATPase classification.

The copper-transporting P-ATPases, which play a key role in cellular copper homeostasis, have been divided traditionally into two subfamilies, the P-ATPases or CopAs and the P-ATPases or CopBs. CopAs selectively export Cu whereas previous studies and bioinformatic analyses have suggested that CopBs are specific for Cu export. Biochemical and spectroscopic characterization of CopB (CopB) show that, while it does bind Cu, the binding site is not the prototypical P-ATPase transmembrane site and does not involve sulfur coordination as proposed previously.

In vitro characterization of a novel Isu homologue from Drosophila melanogaster for de novo FeS-cluster formation.

FeS-clusters are utilized by numerous proteins within several biological pathways that are essential for life. In eukaryotes, the primary FeS-cluster production pathway is the mitochondrial iron-sulfur cluster (ISC) pathway. In Saccharomyces cerevisiae, de novo FeS-cluster formation is accomplished through coordinated assembly with the substrates iron and sulfur by the scaffold assembly protein "Isu1".