Journal
JOURNAL OF BIOLOGICAL CHEMISTRY
Volume 275, Issue 48, Pages 37565-37571Publisher
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M005211200
Keywords
-
Categories
Funding
- NIGMS NIH HHS [R01 GM058626-01A1, GM58626, R01 GM058626] Funding Source: Medline
Ask authors/readers for more resources
ClpB is a member of a protein-disaggregating multi-chaperone system in Escherichia coli, The mechanism of protein-folding reactions mediated by ClpB is currently unknown, and the functional role of different sequence regions in ClpB is under discussion. We have expressed and purified the full-length ClpB and three truncated variants with the N-terminal, C terminal, and a double N- and C-terminal deletion. We studied the protein concentration-dependent and ATP-induced oligomerization of ClpB, casein-induced activation of ClpB ATPase, and ClpB-assisted reactivation of denatured firefly luciferase, We found that both the N- and C-terminal truncation of ClpB strongly inhibited its chaperone activity. The reasons for such inhibition were different, however, for the N- and C-terminal truncation. Deletion of the C-terminal domain inhibited the self-association of ClpB, which led to decreased affinity for ATP and to decreased ATPase and chaperone activity of the C terminally truncated variants. In contrast, deletion of the N-terminal domain did not inhibit the self-association of ClpB and its basal ATPase activity but decreased the ability of casein to activate ClpB ATPase, These results indicate that the N-terminal region of ClpB may contain a functionally significant protein-binding site, whereas the main role of the C-terminal region is to support oligomerization of ClpB.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available