Multiparameter kinetic study on the unfolding and refolding of bovine carbonic anhydrase B
- 14 October 1980
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 19 (21), 4738-4743
- https://doi.org/10.1021/bi00562a003
Abstract
The kinetics of unfolding and refolding of bovine carbonic anhydrase B by guanidinium chloride were studied by simultaneously monitoring several spectroscopic parameters, each of which reflects certain unique conformational features of the protein molecule. Far-UV circular dichroism (CD) was used to follow the secondary structural change, UV difference absorption was used to follow the exposure or burying of aromatic amino acid residues, and near-UV CD was used to follow tertiary structural changes during unfolding and refolding. The unfolding is described by 2 unimolecular rate processes, and refolding is described by 3 unimolecular rate processes. The minimum number of conformational species involved in the mechanism is 5. The refolding of the protein followed by these 3 parameters indicates that the process consists of an initial rapid phase in which the random-coiled protein is converted to an intermediate state(s) having secondary structure comparable to that of the native protein. This is followed by the burying of the aromatic amino acid residues to form the interior of the protein molecule. The protein molecule acquires its tertiary structure and folds into a unique conformation with the formation of aromatic clusters.This publication has 4 references indexed in Scilit:
- Denaturation of cobalt-carbonic anhydrase B from bovine erythrocyteBiopolymers, 1979
- Possible implications of many proline residues for the kinetics of protein unfolding and refoldingJournal of Molecular Biology, 1978
- Reactivation kinetics of guanidine denatured bovine carbonic anhydrase BArchives of Biochemistry and Biophysics, 1978
- Unfolding and refolding occur much faster for a proline-free proteins than for most proline-containing proteins.Proceedings of the National Academy of Sciences, 1977