SECONDARY STRUCTURE OF GLOBULAR-PROTEINS AT THE EARLY AND THE FINAL STAGES IN PROTEIN-FOLDING

The ellipticities for an early transient intermediate in refolding obs erved by kinetic circular dichroism measurements at 220-225 nm for 14 different proteins are summarized, and the ellipticity values are comp ared with those for the final native proteins and also with the ellipt icities expected from a physical theory of protein and polypeptide sec ondary structure. The results show that a substantial part of the prot ein secondary structure is in general formed in the earliest detectabl e intermediate in refolding and that the ellipticities in both the nat ive and the intermediate states are consistent with the physical theor y of protein secondary structure.