Human type-alpha transforming growth factors undergoes slow conformational exchange between multiple backbone conformations as characterized by nitrogen-15 relaxation measurements

Examination of the conformational dynamics of human type-alpha transforming growth factor, hTGF alpha, in aqueous solution at neutral pH by nitrogen-15 relaxation measurements reveals the interconversions between multiple protein conformation on the microsecond time scale. Disulfide bond isomerization in the solution structure of hTGF alpha, partial unfolding of the core beta-sheet and hinge-binding motions between the C- and N-terminal subdomains account for these dynamic fluctuations.