The C-terminal sequence of the chaperonin GroES is required for oligomerization.
The Escherichia coli protein GroES is a co-chaperonin that is able to assist GroEL in the refolding of proteins. GroES is a heptamer of seven identical subunits. Recent work has focused on the structural aspects of GroES. We have investigated the role of the C-terminal portion of GroES on its oligomerization. Limited proteolysis of GroES by carboxypeptidase Y gives a product in which the C-terminal 7 amino acid residues have been removed. Sedimentation velocity analysis reveals that the truncated form of GroES is unable to reassemble. The results presented here implicate the C-terminal sequence in intermonomer actions within the GroES oligomer. In addition, this work provides experimental verification of predictions implied in the recent x-ray determination of the GroES structure (Hunt, J. F., Weaver, A. J., Landry, S. J., Gierasch, L. M., and Deisenhofer, J. Nature, in press).
Department of Biochemistry, University of Texas Health Sciences Center, San Antonio 78240-7760, USA.
J W
JW
Seale
P M
PM
Horowitz
D000595:Amino Acid Sequence; D002268:Carboxypeptidases / Q000378:metabolism; D043402:Cathepsin A; D018835:Chaperonin 10 / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification; D017510:Protein Folding
D018835:Chaperonin 10; D046911:Macromolecular Substances; D010446:Peptide Fragments; D002268:Carboxypeptidases; D043402:Cathepsin A