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Improved high-force magnetic tweezers for stretching and refolding of proteins and short DNA.

ABSTRACT: Although magnetic tweezers have many unique advantages in terms of specificity, throughput, and force stability, this tool has had limited application on short tethers because accurate measurement of force has been difficult for short tethers under large tension. Here, we report a method that allows us to apply magnetic tweezers to stretch short biomolecules with accurate force calibration over a wide range of up to 100 pN. We demonstrate the use of the method by overstretching of a short DNA and unfolding/refolding a protein of filamin A immunoglobulin domains 1-8. Other potential applications of this method are also discussed.

SUBMITTER: Chen H

PROVIDER: S-EPMC3325116 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Improved high-force magnetic tweezers for stretching and refolding of proteins and short DNA.

Chen Hu H Fu Hongxia H Zhu Xiaoying X Cong Peiwen P Nakamura Fumihiko F Yan Jie J

Biophysical journal 20110101 2

Although magnetic tweezers have many unique advantages in terms of specificity, throughput, and force stability, this tool has had limited application on short tethers because accurate measurement of force has been difficult for short tethers under large tension. Here, we report a method that allows us to apply magnetic tweezers to stretch short biomolecules with accurate force calibration over a wide range of up to 100 pN. We demonstrate the use of the method by overstretching of a short DNA an ...[more]

PMID: 21244848

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