CsgE / CsgF / CsgG - Curli Product Assembly/ Transport Component
These proteins form transmembrane pores that usually allow the energy independent passage of solutes across a membrane. The transmembrane portions of these proteins consist of β-strands which form a β-barrel. These porin-type proteins are found in the outer membranes of Gram-negative bacteria, mitochondria, plastids and possibly acid-fast Gram-positive bacteria.
95 subfamilies has been described by the Transporter Classification Database (TCDB).
CsgG belongs to the subfamily "The Curli Fiber Subunit, CsgA, Porin, CsgG (CsgG) Family"
CsgG Background Information
Curli are extracellular amyloid fibers produced by enteric bacteria (e.g. Escherichia coli) that are critical for biofilm formation and adhesion to biotic and abiotic surfaces. CsgA and CsgB are the major and minor curli subunits, respectively, while CsgE, CsgF, and CsgG direct the extracellular localization and assembly of curli subunits into fibers
CsgG forms oligomeric pores in the outer membranes of enteric bacteria. Evidence has been presented showing that the CsgA curli subunit is exported across the outer membranes via the CsgG protein.
CsgG forms oligomeric pores in the outer membranes of enteric bacteria. Evidence has been presented showing that the CsgA curli subunit is exported across the outer membranes of enteric bacteria via the CsgG protein.
Proteins include but ar not limited to UniProt P0A204 (Salmonella typhimurium); UniProt P0AEA2 (Escherichia coli strain K12); UniProt A8AI45 (Citrobacter koseri)
CsgG forms an oligomeric transport complex composed of nine anticodon-binding-domain-like units that give rise to a 36-stranded β-barrel that traverses the bilayer and is connected to a cage-like vestibule in the periplasm.
Bilayer recordings Orbit instrument family
Reviews and Links
- Van Gervn et al. (2015) Bacterial amyloid formation: structural insights into curli biogensis. Trends Microbiol. 23(11): 693–706.