6C12

SDHA-SDHE complex

Summary for 6C12

• Entry DOI: 10.2210/pdb6c12/pdb
• Descriptor: Succinate dehydrogenase flavoprotein subunit, FAD assembly factor SdhE, FLAVIN-ADENINE DINUCLEOTIDE, ... (5 entities in total)
• Functional Keywords: succinate dehydrogenase, assembly factor, oxidoreductase-chaperon complex, oxidoreductase/chaperon
• Biological source: Escherichia coli (strain K12); More
• Total number of polymer chains: 4
• Total formula weight: 154723.90

Authors

Maher, M.J. (deposition date: 2018-01-03, release date: 2018-03-07, Last modification date: 2024-11-20)

Primary citation

Maher, M.J.,Herath, A.S.,Udagedara, S.R.,Dougan, D.A.,Truscott, K.N.
Crystal structure of bacterial succinate:quinone oxidoreductase flavoprotein SdhA in complex with its assembly factor SdhE.
Proc. Natl. Acad. Sci. U.S.A., 115:2982-2987, 2018

PubMed Abstract: Succinate:quinone oxidoreductase (SQR) functions in energy metabolism, coupling the tricarboxylic acid cycle and electron transport chain in bacteria and mitochondria. The biogenesis of flavinylated SdhA, the catalytic subunit of SQR, is assisted by a highly conserved assembly factor termed SdhE in bacteria via an unknown mechanism. By using X-ray crystallography, we have solved the structure of SdhE in complex with SdhA to 2.15-Å resolution. Our structure shows that SdhE makes a direct interaction with the flavin adenine dinucleotide-linked residue His45 in SdhA and maintains the capping domain of SdhA in an "open" conformation. This displaces the catalytic residues of the succinate dehydrogenase active site by as much as 9.0 Å compared with SdhA in the assembled SQR complex. These data suggest that bacterial SdhE proteins, and their mitochondrial homologs, are assembly chaperones that constrain the conformation of SdhA to facilitate efficient flavinylation while regulating succinate dehydrogenase activity for productive biogenesis of SQR.

PubMed: 29514959
DOI: 10.1073/pnas.1800195115

Experimental method

X-RAY DIFFRACTION (2.15 Å)