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The reaction cycle of GroEL and GroES in chaperonin-assisted protein folding
1Cellular Biochemistry and Biophysics Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
Abstract:
The reaction mechanism of protein folding by the chaperonin GroEL and its regulator GroES has been defined. GroES and substrate protein counteract each other's effects on GroEL: whereas GroES stabilizes GroEL in the ADP-bound state, binding of unfolded polypeptide within the cavity of the GroEL cylinder triggers ADP and GroES release. Upon ADP-ATP exchange, GroES reassociates with GroEL and ATP hydrolysis discharges the bound protein for folding. Partially folded protein rebinds to the chaperonin, thus perpetuating the cycle until folding is complete.
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