A
molten globule (
MG) is an intermediate state in the folding pathway of a protein that has some secondary and tertiary structure, but lacks the well packed amino acid side chains that characterize the native state (
N) of a protein. The transition from a denatured (
U) state to a molten globule may be a two state process
- U ↔ MG
Or it may be a continuous transition, with no cooperativity and no apparent "switch" from one form to the other. In any event, a model that can be used in some proteins is a three step process:
- U ↔ MG ↔ N
That the products of de novo protein design have been found to be molten globules instead of native state proteins is an issue in the design of purely synthetic proteins.
Further information
- Is the molten globule a third phase of proteins?
http://www.stanford.edu/group/pandegroup/papers/MGpnas.pdf