Stanford Synchrotron Radiation Lightsource

Protein enzymes can contain specific sites to bind copper atoms for a variety of purposes. Depending on the environment and role of the enzyme, different amino acid residues are employed to bind Cu(I).  Oxygenase enzymes employing Cu(I) often use both methionine (Met) and histidine (His) amino acids, while membrane transport proteins often use Met and not His. The identity and placement of the amino acids coordinating the Cu(I) atoms create different local environments, but it is unclear how this affects the Cu(I) atom to fulfill the role it serves for the enzyme or transporter.  A team of scientists has recently developed a new experimental approach to measure the local environmental effects on Cu(I) reactivity.