3DML

Crystal structure of the periplasmic thioredoxin SoxS from Paracoccus pantotrophus (reduced form)

Summary for 3DML

• Entry DOI: 10.2210/pdb3dml/pdb
• Related: 3D4T
• Descriptor: Putative uncharacterized protein (2 entities in total)
• Functional Keywords: thioredoxin, oxidoreductase, sulfur oxidation, thiol-disulfide oxidoreductase
• Biological source: Paracoccus denitrificans
• Total number of polymer chains: 1
• Total formula weight: 13315.22

Authors

Carius, Y.,Friedrich, C.G.,Scheidig, A.J. (deposition date: 2008-07-01, release date: 2008-08-26, Last modification date: 2025-08-06)

Primary citation

Carius, Y.,Rother, D.,Friedrich, C.G.,Scheidig, A.J.
The structure of the periplasmic thiol-disulfide oxidoreductase SoxS from Paracoccus pantotrophus indicates a triple Trx/Grx/DsbC functionality in chemotrophic sulfur oxidation.
Acta Crystallogr.,Sect.D, 65:229-240, 2009

PubMed Abstract: The periplasmic thiol-disulfide oxidoreductase SoxS is beneficial for the sulfur-oxidizing (Sox) phenotype of the facultative chemotrophic bacterium Paracoccus pantotrophus and is not part of the Sox enzyme system. SoxS combines features of thioredoxins, glutaredoxins and the thiol-disulfide oxidoreductases of the Dsb family in structure, target specificity and reaction. The structure of SoxS was solved in oxidized and reduced forms at 2.1 and 1.9 A resolution, respectively. SoxS revealed high structural homology to typical cytoplasmic bacterial thioredoxins. In contrast, SoxS contained the active-site motif Pro-Gly-Cys-Leu-Tyr-Cys that is not present in other thioredoxins. Interestingly, the sequence of this motif is closely related to the Pro-Gly-Cys-Pro-Tyr-Cys sequence of some glutaredoxins and to the Pro-Xaa-Cys-Xaa-Tyr-Cys sequences of some members of the DsbC and DsbG subfamilies of thiol-disulfide oxidoreductases. Furthermore, the proposed substrate of SoxS, the interprotein disulfide of SoxY, Cys110(Y)-Cys110(Y), is structurally similar to oxidized glutathione. However, SoxS is proposed to specifically reduce the interprotein disulfide between two SoxY subunits, releasing a heterodimeric SoxYZ as an active part of the sulfur-oxidation cycle.

PubMed: 19237745
DOI: 10.1107/S0907444908043023

Experimental method

X-RAY DIFFRACTION (1.9 Å)