Revival of inactive glyceraldehyde 3-phosphate dehydrogenase in human cataract lenses by reduction

In this study, endogenous as well as synthetic reducing systems were shown to reduce the disulphide bonds formed in glyceraldehyde 3-phosphate dehydrogenase, an important glycolytic enzyme previously reported to have lost its activity in human cataract lenses, resulting in reviving the activity of this enzyme. Disulphide bond formation is a non-specific posttranslational modification of proteins, which leads to a loss of function of the affected protein. When an enzyme is targeted, this harmful effect can be easily detected by monitoring the change of activity. Endogenous reducing systems are responsible for breaking these bonds and returning the protein (enzyme) to its natural state, when these mechanisms fail to do so, the loss of enzyme activity will be permanent.