Copper binding triggers compaction in N-terminal tail of human copper pump ATP7B
Artikel i vetenskaplig tidskrift, 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

Författare

T. Mondol

Umeå universitet

J. Åden

Umeå universitet

Pernilla Wittung Stafshede

Chalmers, Biologi och bioteknik, Kemisk biologi

Biochemical and Biophysical Research Communications

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

Vol. 470 3 663-669

Ämneskategorier

Strukturbiologi

DOI

10.1016/j.bbrc.2016.01.085

PubMed

26797276