Towards understanding the functions of the GroEL and ClpX chaperone systems in Escherichia coli.
Published: 2004
Language: eng
Number of pages: 128
Description: Molecular chaperones are proteins that assist in folding, refolding, disaggregation, or degradation of other proteins in the cell. This thesis includes studies of two bacterial chaperones, GroEL, which mediates protein folding, and ClpX, which mediates protein unfolding and directs proteins for degradation by ClpP. GroEL has previously been implicated in the refolding of the multisubunit bacterial RNA polymerase (RNAP). I found that GroEL was not essential for the refolding of the alpha and o subunits of RNAP. Previous studies have indicated that the N-terminal Zinc Binding Domain (ZBD) of ClpX is involved in substrate recognition. Using degradation assays and competition studies, I found that the ZBD of ClpX is important for recognizing a certain set of substrates. Placement of an N-terminal tag on ClpX results in cleavage of that tag in the presence of ClpP and ATP. This suggests that a conformational change takes place in ClpX involving the ZBD.
Notes: Adviser:  Walid A. Howy.

Thesis (M.Sc.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Masters Abstracts International, Volume: 43-03, page: 0847.

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