Dataset Information

Signatures of hydrophobic collapse in extended proteins captured with force spectroscopy.

ABSTRACT: We unfold and extend single proteins at a high force and then linearly relax the force to probe their collapse mechanisms. We observe a large variability in the extent of their recoil. Although chain entropy makes a small contribution, we show that the observed variability results from hydrophobic interactions with randomly varying magnitude from protein to protein. This collapse mechanism is common to highly extended proteins, including nonfolding elastomeric proteins like PEVK from titin. Our observations explain the puzzling differences between the folding behavior of highly extended proteins, from those folding after chemical or thermal denaturation. Probing the collapse of highly extended proteins with force spectroscopy allows separation of the different driving forces in protein folding.

SUBMITTER: Walther KA

PROVIDER: S-EPMC1876547 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature

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Signatures of hydrophobic collapse in extended proteins captured with force spectroscopy.

Walther Kirstin A KA Gräter Frauke F Dougan Lorna L Badilla Carmen L CL Berne Bruce J BJ Fernandez Julio M JM

Proceedings of the National Academy of Sciences of the United States of America 20070430 19

We unfold and extend single proteins at a high force and then linearly relax the force to probe their collapse mechanisms. We observe a large variability in the extent of their recoil. Although chain entropy makes a small contribution, we show that the observed variability results from hydrophobic interactions with randomly varying magnitude from protein to protein. This collapse mechanism is common to highly extended proteins, including nonfolding elastomeric proteins like PEVK from titin. Our ...[more]

PMID: 17470816

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Dataset Information

Signatures of hydrophobic collapse in extended proteins captured with force spectroscopy.

Publications

Signatures of hydrophobic collapse in extended proteins captured with force spectroscopy.

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