Solution structure of the apo and copper(I)-loaded human metallochaperone HAH1.
The human metallochaperone HAH1 has been produced in Escherichia coli with four additional amino acids at the C-terminus and characterized in solution by NMR spectroscopy, both with and without copper(I). The solution structure of the apo-HAH1 monomer has a root-mean-square-deviation (RMSD) of 0.50 A for the coordinates of the backbone atoms and 0.96 A for all heavy atoms. These values compare, respectively, with 0.45 and 0.95 A for copper(I)-HAH1. There are only minor structural rearrangements upon copper(I) binding. In particular, the variation of interatomic interactions around the metal-binding region is limited to a movement of Lys60 toward the metal site. The protein structures are similar to those obtained by X-ray crystallography in a variety of derivatives, with backbone RMSD values below 1 A. In the holoprotein, copper(I) is confirmed to be two coordinated. If these data are compared with those of orthologue proteins, we learn that HAH1 has a lower tendency to change coordination number from two to three. Such a switch in coordination is a key step in copper transfer.
Institute of Physical Chemistry, NCSR Demokritos, 153 10 Aghia Paraskevi Attikis, Greece.
Ioanna
I
Anastassopoulou
Lucia
L
Banci
Ivano
I
Bertini
Francesca
F
Cantini
Efthalia
E
Katsari
Antonio
A
Rosato
D001059:Apoproteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry; D027682:Cation Transport Proteins / Q000737:chemistry* / Q000378:metabolism; D003300:Copper / Q000378:metabolism*; D000079922:Copper Transport Proteins; D006801:Humans; D056511:Metallochaperones; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry* / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D010084:Oxidation-Reduction; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry; D012996:Solutions; D040681:Structural Homology, Protein; D013816:Thermodynamics
C474500:ATOX1 protein, human; C093341:ATX1 protein, S cerevisiae; D001059:Apoproteins; D002352:Carrier Proteins; D027682:Cation Transport Proteins; D000079922:Copper Transport Proteins; D056511:Metallochaperones; D018832:Molecular Chaperones; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D012996:Solutions; D003300:Copper