Design of an optical switch for studying conformational dynamics in individual molecules of GroEL.
We describe the design of an optical switch in the chaperonin GroEL that is opened and closed by its ATP- and cochaperonin GroES-driven conformational changes. The switch, based on a fluorophore and a quencher, is engineered into the single-ring variant of the chaperone, and shows dramatic modulation of its fluorescent intensity in response to the transition of the protein between its allosteric states. It, therefore, forms a sensitive probe for the dynamics of the allosteric transitions of this machine, both in the bulk and in single molecules.
Frank
Gabriel A
GA
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Kipnis
Yakov
Y
Smolensky
Elena
E
Daube
Shirley S
SS
Horovitz
Amnon
A
Haran
Gilad
G
D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D018834:Chaperonin 60 / Q000737:chemistry* / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000378:metabolism*; D008958:Models, Molecular; D055095:Optics and Photonics; D011487:Protein Conformation
D001426:Bacterial Proteins; D018834:Chaperonin 60; D005456:Fluorescent Dyes