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Design of an optical switch for studying conformational dynamics in individual molecules of GroEL.

ABSTRACT: 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.

SUBMITTER: Frank GA

PROVIDER: S-EPMC2632776 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Design of an optical switch for studying conformational dynamics in individual molecules of GroEL.

Frank Gabriel A GA Kipnis Yakov Y Smolensky Elena E Daube Shirley S SS Horovitz Amnon A Haran Gilad G

Bioconjugate chemistry 20080624 7

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 ...[more]

PMID: 18572960

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