Abstract
Protein dimerization or oligomerization resulting from swapping part of the protein between neighboring polypeptide chains is known to play a key role in the regulation of protein function and in the formation of protein aggregates. Glutaredoxin-1 from Clostridium oremlandii (cGrx1) was used as a model to explore the formation of multiple domain-swapped conformations, which were made possible by modulating several hinge-loop residues that can form a pivot for domain swapping. Specifically, two alternative domain-swapped structures were generated and analyzed using nuclear magnetic resonance (NMR), X-ray crystallography, circular-dichroism spectroscopy and hydrogen/deuterium-exchange (HDX) mass spectrometry. The first domain-swapped structure (β3-swap) was formed by the hexameric cGrx1-cMsrA complex. The second domain-swapped structure (β1-swap) was formed by monothiol cGrx1 (C16S) alone. In summary, the first domain-swapped structure of an oxidoreductase in a hetero-oligomeric complex is presented. In particular, a single point mutation of a key cysteine residue to serine led to the formation of an intramolecular disulfide bond, as opposed to an intermolecular disulfide bond, and resulted in modulation of the underlying free-energy landscape of protein oligomerization.
Original language | English |
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Pages (from-to) | 1019-1027 |
Number of pages | 9 |
Journal | IUCrJ |
Volume | 7 |
DOIs | |
Publication status | Published - 2020 Nov 1 |
Bibliographical note
Funding Information:This work was supported by project grants (2018R1A44A1022589, 2020R1A2C2005670 and 2019R1I1A1A01056) from the National Research Foundation funded by the Ministry of Science of Korea.
Publisher Copyright:
© 2020.
Keywords
- disulfide bonds
- domain swapping
- glutaredoxin
- oxidoreductases
ASJC Scopus subject areas
- General Chemistry
- Biochemistry
- General Materials Science
- Condensed Matter Physics