The chaperone-assisted membrane release and folding pathway is sensed by two signal transduction systems

• Published in: The EMBO journal 1997-11, Vol.16 (21), p.6394-6406
• Main Authors: Hal Jones, C., Danese, Paul N., Pinkner, Jerome S., Silhavy, Thomas J., Hultgren, Scott J.
• Format: Article
• Language: English
• Subjects: Adhesins, Escherichia coli - metabolism; Bacterial Outer Membrane Proteins - metabolism; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Biological Transport; chaperone; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli Proteins; Fimbriae Proteins; Fimbriae, Bacterial - metabolism; Heat-Shock Proteins; Macromolecular Substances; Membrane Proteins - metabolism; Models, Biological; Molecular Chaperones - genetics; Molecular Chaperones - metabolism; Periplasmic Proteins; periplasmic stress; periplasmic targeting; Protein Folding; Protein Kinases; Recombinant Fusion Proteins - metabolism; Serine Endopeptidases - metabolism; Sigma Factor - metabolism; signal transduction; Signal Transduction - physiology; Spheroplasts; Transcription Factors - metabolism
• ISSN: 0261-4189; 1460-2075; 1460-2075
• DOI: 10.1093/emboj/16.21.6394

The assembly of interactive protein subunits into extracellular structures, such as pilus fibers in the Enterobacteriaceae, is dependent on the activity of PapD‐like periplasmic chaperones. The ability of PapD to undergo a β zippering interaction with the hydrophobic C‐terminus of pilus subunits facilitates their folding and release from the cytoplasmic membrane into the periplasm. In the absence of the chaperone, subunits remained tethered to the membrane and were driven off‐pathway via non‐productive interactions. These off‐pathway reactions were detrimental to cell growth; wild‐type growth was restored by co‐expression of PapD. Subunit misfolding in the absence of PapD was sensed by two parallel pathways: the Cpx two‐component signaling system and the σE modulatory pathway.