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Structure of the twin-arginine signal-binding protein DmsD from Escherichia coli.

ABSTRACT: The translocation of folded proteins via the twin-arginine translocation (Tat) pathway is regulated to prevent the futile export of inactive substrate. DmsD is part of a class of cytoplasmic chaperones that play a role in preventing certain redox proteins from premature transport. DmsD from Escherichia coli has been crystallized in space group P4(1)2(1)2, with unit-cell parameters a = b = 97.45, c = 210.04 A, in the presence of a small peptide. The structure has been solved by molecular replacement to a resolution of 2.4 A and refined to an R factor of 19.4%. There are four molecules in the asymmetric unit that may mimic a higher order structure in vivo. There appears to be density for the peptide in a predicted binding pocket, which lends support to its role as the signal-recognition surface for this class of proteins.

SUBMITTER: Ramasamy SK

PROVIDER: S-EPMC2720324 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Structure of the twin-arginine signal-binding protein DmsD from Escherichia coli.

Ramasamy Suresh Kumar SK Clemons William M WM

Acta crystallographica. Section F, Structural biology and crystallization communications 20090721 Pt 8

The translocation of folded proteins via the twin-arginine translocation (Tat) pathway is regulated to prevent the futile export of inactive substrate. DmsD is part of a class of cytoplasmic chaperones that play a role in preventing certain redox proteins from premature transport. DmsD from Escherichia coli has been crystallized in space group P4(1)2(1)2, with unit-cell parameters a = b = 97.45, c = 210.04 A, in the presence of a small peptide. The structure has been solved by molecular replacem ...[more]

PMID: 19652330

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