These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Amyloid-like fibril formation of co-chaperonin GroES: nucleation and extension prefer different degrees of molecular compactness.
    Author: Higurashi T, Yagi H, Mizobata T, Kawata Y.
    Journal: J Mol Biol; 2005 Sep 02; 351(5):1057-69. PubMed ID: 16054644.
    Abstract:
    The molecular chaperone GroES, together with GroEL from Escherichia coli, is the best characterized protein of the molecular chaperone family. Here, we report on the in vitro formation of GroES amyloid-like fibrils and the mechanism of formation. When incubated for several weeks at neutral pH in the presence of the denaturant guanidine hydrochloride, GroES formed a typical amyloid fibril; unbranched, twisted, and extended filaments stainable by thioflavin T and Congo red. GroES fibril formation was accelerated by the addition of preformed fibril seeds, in accordance with a nucleation-extension mechanism. Interestingly, whereas the spontaneous formation of GroES fibrils was favored in the structural transition region of GroES dissociation/unfolding, the extension of fibrils from preformed fibril seeds was favored in the region corresponding to an expanded molecular state. We concluded that the two stages of GroES fibril formation prefer different molecular states of the same protein. The significance of this preference is discussed.
    [Abstract] [Full Text] [Related] [New Search]