A way to probe the microenvironment of free sulfhydryls in intact proteins with a series of monofunctional organic mercurials.

Monofunctional organic mercurials (MFOHgs) of different sizes and electronic properties were used to evaluate the accessibility of SH groups in intact proteins. The change in conformation of proteins, such as BLG and OVA, when treated with MFOHgs of increasing size was used as a measure of the accessibility of SH groups contained within these proteins.