Formation of local native-like tertiary structures in the slow refolding reaction of human carbonic anhydrase II as monitored by circular dichroism on tryptophan mutants

The development of asymmetric environments around specific Trp residues during the refolding process of human carbonic anhydrase II (HCAII) was analyzed via near ultraviolet circular dichroism (CD) kinetic measurements. CD kinetic measurements of HCAII refolding indicated the presence of slow kinetic phases that were induced by cis-trans isomerization at proline peptide bonds. Furthermore, the formation of the N-terminal domain was dependent on the prior formation of an enzymatically active native-like conformation in HCAII.