9Y0M
Crystal structure of Escherichia coli DsbA P151T mutant
Summary for 9Y0M
| Entry DOI | 10.2210/pdb9y0m/pdb |
| Descriptor | Thiol:disulfide interchange protein DsbA, DI(HYDROXYETHYL)ETHER, GLYCEROL, ... (4 entities in total) |
| Functional Keywords | thiol oxidase mutant, bacterial foldase, thioredoxin fold, oxidoreductase |
| Biological source | Escherichia coli |
| Total number of polymer chains | 4 |
| Total formula weight | 85564.98 |
| Authors | Cunliffe, T.R.,Heras, B.,Paxman, J.J. (deposition date: 2025-08-28, release date: 2026-03-25, Last modification date: 2026-04-29) |
| Primary citation | Cunliffe, T.,Wang, G.,Penning, S.,Subedi, P.,Totsika, M.,Paxman, J.J.,Heras, B. A universal cis-proline lock defines catalysis in thioredoxin-fold enzymes. Commun Biol, 2026 Cited by PubMed Abstract: Thioredoxin-fold oxidoreductases drive oxidative protein folding and redox homeostasis across all domains of life. They catalyse thiol-disulfide exchange in diverse substrates, yet how they reconcile catalytic precision with substrate diversity remains unclear. Here we show, using high-resolution structures and functional analyses of the Escherichia coli oxidoreductase DsbA, that a conserved cis-proline loop adjacent to the catalytic Cys-Pro-His-Cys motif serves as a universal catalytic lock. The loop positions the substrate cysteine in a right-handed disulfide geometry optimal for exchange, while surrounding surfaces accommodate sequence variation. Substitution of the cis-proline abolishes turnover, whereas mutation of the preceding glycine preserves geometry but reduces efficiency. Comparative structural analyses demonstrate that this cis-proline-dependent hydrogen-bonding scaffold is conserved across thioredoxins, protein disulfide isomerases, peroxiredoxins and bacterial Dsb proteins. This conserved mechanism explains how catalytic fidelity is maintained while enabling substrate versatility and provides a foundation for enzyme engineering and therapeutic development. PubMed: 41981106DOI: 10.1038/s42003-026-10010-8 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.88 Å) |
Structure validation
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