Trisulfides in proteins.

Trisulfides and other oligosulfides are widely distributed in the biological world. In plants, for example, garlic, trisulfides are associated with potentially beneficial properties. However, an extra neutral sulfur atom covalently bound between the two sulfur atoms of a pair of cysteines is not a common post-translational modification, and the number of proteins in which a trisulfide has been unambiguously identified is small.