2HI7

Crystal structure of DsbA-DsbB-ubiquinone complex

Summary for 2HI7

• Entry DOI: 10.2210/pdb2hi7/pdb
• Descriptor: Thiol:disulfide interchange protein dsbA, Disulfide bond formation protein B, ZINC ION, ... (4 entities in total)
• Functional Keywords: disulfide bond, redox, dsbb, membrane protein, ubiquinone, oxidative protein folding, oxidoreductase
• Biological source: Escherichia coli; More
• Cellular location: Periplasm: P0AEG4; Cell inner membrane; Multi-pass membrane protein: P0A6M2
• Total number of polymer chains: 2
• Total formula weight: 41545.64

Authors

Inaba, K.,Murakami, S.,Suzuki, M.,Nakagawa, A.,Yamashita, E.,Okada, K.,Ito, K. (deposition date: 2006-06-29, release date: 2006-12-05, Last modification date: 2024-11-20)

Primary citation

Inaba, K.,Murakami, S.,Suzuki, M.,Nakagawa, A.,Yamashita, E.,Okada, K.,Ito, K.
Crystal Structure of the DsbB-DsbA Complex Reveals a Mechanism of Disulfide Bond Generation
Cell(Cambridge,Mass.), 127:789-801, 2006

PubMed Abstract: Oxidation of cysteine pairs to disulfide requires cellular factors present in the bacterial periplasmic space. DsbB is an E. coli membrane protein that oxidizes DsbA, a periplasmic dithiol oxidase. To gain insight into disulfide bond formation, we determined the crystal structure of the DsbB-DsbA complex at 3.7 A resolution. The structure of DsbB revealed four transmembrane helices and one short horizontal helix juxtaposed with Cys130 in the mobile periplasmic loop. Whereas DsbB in the resting state contains a Cys104-Cys130 disulfide, Cys104 in the binary complex is engaged in the intermolecular disulfide bond and captured by the hydrophobic groove of DsbA, resulting in separation from Cys130. This cysteine relocation prevents the backward resolution of the complex and allows Cys130 to approach and activate the disulfide-generating reaction center composed of Cys41, Cys44, Arg48, and ubiquinone. We propose that DsbB is converted by its specific substrate, DsbA, to a superoxidizing enzyme, capable of oxidizing this extremely oxidizing oxidase.

PubMed: 17110337
DOI: 10.1016/j.cell.2006.10.034

Experimental method

X-RAY DIFFRACTION (3.7 Å)