SwePub
Sök i LIBRIS databas

  Utökad sökning

onr:"swepub:oai:DiVA.org:umu-56557"
 

Sökning: onr:"swepub:oai:DiVA.org:umu-56557" > The C-terminal repe...

The C-terminal repeating units of CsgB direct bacterial functional amyloid nucleation

Hammer, Neal D (författare)
McGuffie, Bryan A (författare)
Zhou, Yizhou (författare)
visa fler...
Badtke, Matthew P (författare)
Reineke, Ashley A (författare)
Brännström, Kristoffer (författare)
Umeå universitet,Institutionen för medicinsk kemi och biofysik
Gestwicki, Jason E (författare)
Olofsson, Anders (författare)
Umeå universitet,Institutionen för medicinsk kemi och biofysik
Almqvist, Fredrik (författare)
Umeå universitet,Kemiska institutionen,Umeå Center for Microbial Research
Chapman, Matthew R (författare)
Umeå universitet,Institutionen för medicinsk kemi och biofysik
visa färre...
 (creator_code:org_t)
Elsevier, 2012
2012
Engelska.
Ingår i: Journal of Molecular Biology. - : Elsevier. - 0022-2836 .- 1089-8638. ; 422:3, s. 376-389
Relaterad länk:
https://europepmc.or...
visa fler...
https://urn.kb.se/re...
https://doi.org/10.1...
visa färre...
  • Tidskriftsartikel (refereegranskat)
Abstract Ämnesord
Stäng  
  • Curli are functional amyloids produced by enteric bacteria. The major curli fiber subunit, CsgA, self-assembles into an amyloid fiber in vitro. The minor curli subunit protein, CsgB, is required for CsgA polymerization on the cell surface. Both CsgA and CsgB are composed of five predicted β–strand-loop-β–strand-loop repeating units that feature conserved glutamine and asparagine residues. Because of this structural homology, we proposed that CsgB might form an amyloid template that initiates CsgA polymerization on the cell surface. To test this model, we purified wild-type CsgB, and found that it self-assembled into amyloid fibers in vitro. Preformed CsgB fibers seeded CsgA polymerization as did soluble CsgB added to the surface of cells secreting soluble CsgA. To define the molecular basis of CsgB nucleation, we generated a series of mutants that removed each of the five repeating units. Each of these CsgB deletion mutants was capable of self-assembly in vitro. In vivo, membrane-localized mutants lacking the 1st, 2nd or 3rd repeating units were able to convert CsgA into fibers. However, mutants missing either the 4th or 5th repeating units were unable to complement a csgB mutant. These mutant proteins were not localized to the outer membrane, but were instead secreted into the extracellular milieu. Synthetic CsgB peptides corresponding to repeating units 1, 2 and 4 self assembled into ordered amyloid polymers, while peptides corresponding to repeating units 3 and 5 did not, suggesting that there are redundant amyloidogenic domains in CsgB. Our results suggest a model where the rapid conversion of CsgB from unstructured protein to a β-sheet-rich amyloid template anchored to the cell surface is mediated by the C-terminal repeating units.

Ämnesord

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)
NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

Nyckelord

functional amyloid
nucleator
polymerization

Publikations- och innehållstyp

ref (ämneskategori)
art (ämneskategori)

Hitta via bibliotek

Till lärosätets databas

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy