Title | Characterization of a stalled complex on the β-barrel assembly machine. |
Publication Type | Journal Article |
Year of Publication | 2016 |
Authors | Lee, J, Xue, M, Wzorek, JS, Wu, T, Grabowicz, M, Gronenberg, LS, Sutterlin, HA, Davis, RM, Ruiz, N, Silhavy, TJ, Kahne, DE |
Journal | Proc Natl Acad Sci U S A |
Volume | 113 |
Issue | 31 |
Pagination | 8717-22 |
Date Published | 2016 Aug 02 |
ISSN | 1091-6490 |
Keywords | Bacterial Outer Membrane Proteins, Escherichia coli, Escherichia coli Proteins, Models, Molecular, Protein Binding, Protein Conformation, Protein Folding |
Abstract | <p>The assembly of β-barrel proteins into membranes is mediated by an evolutionarily conserved machine. This process is poorly understood because no stable partially folded barrel substrates have been characterized. Here, we slowed the folding of the Escherichia coli β-barrel protein, LptD, with its lipoprotein plug, LptE. We identified a late-stage intermediate in which LptD is folded around LptE, and both components interact with the two essential β-barrel assembly machine (Bam) components, BamA and BamD. We propose a model in which BamA and BamD act in concert to catalyze folding, with the final step in the process involving closure of the ends of the barrel with release from the Bam components. Because BamD and LptE are both soluble proteins, the simplest model consistent with these findings is that barrel folding by the Bam complex begins in the periplasm at the membrane interface.</p> |
DOI | 10.1073/pnas.1604100113 |
Alternate Journal | Proc Natl Acad Sci U S A |
PubMed ID | 27439868 |
PubMed Central ID | PMC4978274 |
Grant List | R01 GM100951 / GM / NIGMS NIH HHS / United States R35 GM118024 / GM / NIGMS NIH HHS / United States T32 GM007598 / GM / NIGMS NIH HHS / United States R01 GM034821 / GM / NIGMS NIH HHS / United States F32 GM108258 / GM / NIGMS NIH HHS / United States R01 AI081059 / AI / NIAID NIH HHS / United States R37 GM034821 / GM / NIGMS NIH HHS / United States F31 GM116210 / GM / NIGMS NIH HHS / United States |