EVIDENCE FOR AN UNFOLDING AND REFOLDING PATHWAY IN CYTOCHROME-C

It has been suggested that three partially unfolded forms detected in a native state hydrogen exchange study of oxidized cytochrome c may re present sequential intermediates in an unfolding-refolding pathway. To better define the structure of each intermediate a 'stability labelin g' method was used in which the stability of a given segment against u nfolding was changed. The condition - folded or unfolded - of the stab ility-labeled segment in each intermediate could then be determined. T he structures found are discrete and native-like and are just those ne cessary for a sequential pathway.