Copper binding triggers compaction in N-terminal tail of human copper pump ATP7B
Journal article, 2016

Protein conformational changes are fundamental to biological reactions. For copper ion transport, the multi-domain protein ATP7B in the Golgi network receives copper from the cytoplasmic copper chaperone Atox1 and, with energy from ATP hydrolysis, moves the metal to the lumen for loading of copper dependent enzymes. Although anticipated, conformational changes involved in ATP7B's functional cycle remain elusive. Using spectroscopic methods we here demonstrate that the four most N-terminal metal binding domains in ATP7B, upon stoichiometric copper addition, adopt a more compact arrangement which has a higher thermal stability than in the absence of copper. In contrast to previous reports, no stable complex was found in solution between the metal-binding domains and the nucleotide-binding domain of ATP7B. Metal-dependent movement of the first four metal-binding domains in ATP7B may be a trigger that initiates the overall catalytic cycle.

Copper transport

Protein-protein interactions

NMR

Metalloenzymes

Circular dichroism

Conformational changes

Author

T. Mondol

Umeå University

J. Åden

Umeå University

Pernilla Wittung Stafshede

Chalmers, Biology and Biological Engineering, Chemical Biology

Biochemical and Biophysical Research Communications

0006-291X (ISSN) 1090-2104 (eISSN)

Vol. 470 3 663-669

Subject Categories

Structural Biology

DOI

10.1016/j.bbrc.2016.01.085

PubMed

26797276

More information

Latest update

2/27/2018