| Bioinorganic chemistry, a discipline that bridges chemistry and biology, has become increasingly popular as new techniques and analytical methods have emerged to study metals in biological systems. One such technique that has become increasingly important in the last 10 to 20 years is isothermal titration calorimetry (ITC). ITC provides a full thermodynamic spectrum of a chemical event and is utilized by the bioinorganic community because of its sensitivity, reproducibility, and ability to analyze otherwise "silent" metals that are difficult to study by traditional methods. Thermodynamic data provides information regarding the stability of a complex and thus the potential for a reaction to occur. When the thermodynamics of a system are known, one can predict how the system will respond to changes in its environment whether the change is introduced through the presence of another protein, metal, or other species that are involved in the equilibrium state of the system. This body of work made extensive use of ITC to study biologically and chemically important interactions of toxic and essential metals with thiol-containing compounds, such as metal detoxification, storage, and gene regulatory proteins. Complementary biophysical techniques, including circular dichroism, UV-visible and fluorescence spectroscopies were also used in these investigations to better characterize the interaction of these metal-requiring proteins. |
