Structural Insights into the Incorporation of the Mo Cofactor into Sulfite Oxidase from Site-Directed Spin Labeling
- Mononuclear molybdoenzymes catalyze a broad range of redox reactions and are highly conserved in all kingdoms of life. This study addresses the question of how the Mo cofactor (Moco) is incorporated into the apo form of human sulfite oxidase (hSO) by using site-directed spin labeling to determine intramolecular distances in the nanometer range. Comparative measurements of the holo and apo forms of hSO enabled the localization of the corresponding structural changes, which are localized to a short loop (residues 263-273) of the Moco-containing domain. A flap-like movement of the loop provides access to the Moco binding-pocket in the apo form of the protein and explains the earlier studies on the in vitro reconstitution of apo-hSO with Moco. Remarkably, the loop motif can be found in a variety of structurally similar molybdoenzymes among various organisms, thus suggesting a common mechanism of Moco incorporation.
Author details: | Aaron Hahn, Christopher Engelhard, Stefan ReschkeGND, Christian Teutloff, Robert Bittl, Silke LeimkühlerORCiDGND, Thomas Risse |
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DOI: | https://doi.org/10.1002/anie.201504772 |
ISSN: | 1433-7851 |
ISSN: | 1521-3773 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/26286921 |
Title of parent work (English): | Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition |
Publisher: | Wiley-VCH |
Place of publishing: | Weinheim |
Publication type: | Article |
Language: | English |
Year of first publication: | 2015 |
Publication year: | 2015 |
Release date: | 2017/03/27 |
Tag: | EPR spectroscopy; biocatalysis; cofactors; enzymes; protein structures |
Volume: | 54 |
Issue: | 40 |
Number of pages: | 5 |
First page: | 11865 |
Last Page: | 11869 |
Funding institution: | DFG; Studienstiftung des deutschen Volkes |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Biochemie und Biologie |
Peer review: | Referiert |