Differences in hydrogen exchange behavior between the oxidized and reduced forms of Escherichia coli thioredoxin.
| Publication Type | Academic Article |
| Authors | Kaminsky S, Richards F |
| Journal | Protein Sci |
| Volume | 1 |
| Issue | 1 |
| Pagination | 10-21 |
| Date Published | 01/01/1992 |
| ISSN | 0961-8368 |
| Keywords | Escherichia coli, Thioredoxins |
| Abstract | Amide proton exchange of thioredoxin is used to monitor the structural effects of reduction of its single disulfide. An effective 3-5-proton difference between the oxidized and reduced protein form is observed early in proton out-exchange of the whole protein, which is independent of temperature in the range of 5-45 degrees C, indicating that redox-sensitive changes are probably not due to low-energy structural fluctuations. Medium resolution hydrogen exchange experiments have localized the redox-sensitive amide protons to two parts of the sequence that are distant from each other in the three-dimensional structure: the active-site turn and the first beta-strand. The sum of the proton differences observed in the peptides from these regions is equal to that of the whole protein, indicating that all redox-sensitive hydrogen exchange effects are observed in the peptide experiments. A model combining structural changes within the protein matrix with changes in the surface hydration properties is proposed as a mechanism for the communication between distant sites within the protein. Sound velocity and density measurements of reduced and oxidized thioredoxin are presented in the accompanying paper (Kaminsky, S.M. & Richards, F.M., 1992, Protein Sci. 1, 22-30). |
| DOI | 10.1002/pro.5560010103 |
| PubMed ID | 1339022 |
| PubMed Central ID | PMC2142074 |