Chaperones Atxl-like

Sequence References for Atxl-like Copper Chaperones and Their Target Domains... 

Bacterial copper proteins are found only in the plasma membrane (Gram-positive bacteria) or in the plasma membrane and the periplasm (Gram-negative bacteria), not in the bacterial cytoplasm. However, cyanobacteria do have copper proteins in their cytoplasm. These important photosynthetic bacteria require copper for plastocyanin, which plays a critical role in the photosynthetic electron transport chain. Both plastocyanin and cytochrome c oxidase are found in the thylakoid compartments within the cytoplasm. In Synechocystis, the Cu(I) Pie-ATPase CtaA imports Cu(I). A second ATPase, PacS, imports Cu(I) into the thylakoid, and the Atxl-like copper chaperone ScAtxl is believed to deliver Cu(I) from CtaA to PacS (Fig. 8.6). 

The Hahl structures provide insight into the molecular mechanism of metal transfer between the Atxl-like chaperones and their partner ATPases. The target proteins of Hahl are the Menkes and Wilson disease proteins (Section 8.8.2.1). In the Cu Hahl structure, the coordination geometry is distorted tetrahedral with three Cu "S distances of 2.3 A and the fourth sulfur at... 

---