The Protein-disulfide Isomerase DsbC Cooperates with SurA and DsbA in the Assembly of the Essential β-Barrel Protein LptD

• DOI: 10.1074/jbc.m110.119321
• Publication Date: 2010-07-09T00:19:34Z
• Authors: Katleen Denoncin; Didier Vertommen; Eunok Paek; Jean-FranÇois Collet
• Keywords: DsbA; Prolyl isomerase; Chaperone (clinical)

The assembly of the β-barrel proteins present in outer membrane (OM) Gram-negative bacteria is poorly characterized. After translocation across inner membrane, unfolded are escorted periplasm by chaperones that reside within this compartment. Two partially redundant chaperones, SurA and Skp, considered to transport bulk mass proteins. We found periplasmic disulfide isomerase DsbC cooperates with thiol oxidase DsbA folding essential protein LptD. LptD inserts lipopolysaccharides OM. It also only more than two cysteine residues. surAdsbC mutants, but not skpdsbC exhibit a synthetic phenotype. They have decreased OM integrity, which due lack activity DsbC. isolated mixed complex As such, identified as first substrate localized Thus, electrons flowing from cytoplasmic thioredoxin system maintain integrity assisting one most important