Family 9.A.11 - The Copper Transporter-1 Family       

Family ID: 53383

A single protein (Ctr1p) of Saccharomyces cerevisiaewas initally characterized as a high affinity Cu+ uptake permease. The protein (406 residues in length) possesses N-terminal repeats rich in serine and methionine that might be involved in copper binding. Ctr1p includes a repeated M-XXM motif that occurs 11 times. Two or three putative transmembrane a-helical spanners (residues 153-173 and either 251-271 or 241-261 and 262-281) and a C-terminal region that is O-glycosylated characterize the protein. Ctr1p is probably present in the membrane as an oligomer. Its mechanism of energy coupling has not been investigated. The synthesis of Ctr1p is induced by copper deficiency and repressed by copper excess. The protein transports Cu+, but not Cu2+ or any other metal ion. A homologue is present in Candida albicans. The N-terminal repeat sequence is found in a number of proteins including putative DNA binding proteins.