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Processive enzyme mimic: Kinetics and thermodynamics of the threading and sliding process.

ABSTRACT: The kinetics and thermodynamics of the threading and dethreading process of polymers through the cavity of a synthetic toroidal host is investigated by studying its complexation with a series of end-functionalized polymers of different lengths containing an end group that is selectively recognized by the host. The system is designed in such a way that complexation is only observed if the host has traveled all of the way across the complete polymer. Detailed kinetic investigations using fluorescence spectroscopy have revealed that the barrier for this process is length dependent and most likely related to the stretching of the polymer. Moreover, the results indicate that our previously reported processive enzyme mimic most likely operates by randomly sliding along its macromolecular substrate.

SUBMITTER: Coumans RG

PROVIDER: S-EPMC1750920 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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Processive enzyme mimic: Kinetics and thermodynamics of the threading and sliding process.

Coumans Ruud G E RG Elemans Johannes A A W JA Nolte Roeland J M RJ Rowan Alan E AE

Proceedings of the National Academy of Sciences of the United States of America 20061215 52

The kinetics and thermodynamics of the threading and dethreading process of polymers through the cavity of a synthetic toroidal host is investigated by studying its complexation with a series of end-functionalized polymers of different lengths containing an end group that is selectively recognized by the host. The system is designed in such a way that complexation is only observed if the host has traveled all of the way across the complete polymer. Detailed kinetic investigations using fluoresce ...[more]

PMID: 17172453

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