Expression and characterization of potential Cu(I) transport ATPase from the psychrophilic bacterium Bizionia argentinensis

NOELIA I. BURGARDT; F. LUIS GONZÁLEZ FLECHA

Chascomus

Congreso; IV Latin American Meeting on Biological Inorganic Chemistry; 2014

Society of Biological Inorganic Chemistry

The relationships between membrane protein folding, function and stability are the main topics of research in our group1. To explore this subject we selected the PIB-ATPase family as a model. These integral membrane proteins actively transport copper through the cell membrane2. Recently, it was obtained the first crystal structure of a copper transporting PIB-ATPase (CopA) from Legionella pneumophila3 We have previously demonstrated that the thermophilic copper transporting PIB-ATPase from Archaeglobus fulgidus undergoes irreversible thermal denaturation due to a partial unfolding of the aminoacidic chain mainly at the level of the cytoplasmatic domains4. Furthermore, we found that guanidinium hydrochloride induce a reversible unfolding of CopA, allowing the complete thermodynamic characterization of the folding process5. To further explore this issue we decided to perform a comparative study of the structure-folding-function relationships in a set of copper transporting PIB-ATPases from mesophilic and psychrophilic organisms. As the psychrophilic partner we select a potential cooper transport ATPase from the recently discovered psychrophilic bacteria Bizionia argentinensis (JUB59-T), isolated from the Argentine Antarctic6,7. Here we present the cloning, expression and preliminary characterization of this psychrophilic CopA (BaCopA).