Abstract
Many proteins are fully denatured and separated into component polypeptide chains in 6M guanidine hydrochloride containing mercaptoethanol and a chelating agent. In this and similar denaturing solvents, polypeptide chains of molecular weights from 2,000 to 100,000 can be eluted from 6 percent agarose columns and separated according to molecular weight. By this procedure molecular weights may be assigned to proteins (including many normally insoluble in nondenaturing solvents) without the uncertainties that arise when native molecules of unknown shape are studied.