Surfactants modify the torsion properties of proteins: a single molecule study

- Magnetic tweezers show increased twisting of proteins to surfactant exposure.
- Tween 20 decreases the torsional rigidity of protein-G-IgG more than SDS.
- Far-UV and near-UV Circular Dichroism do not show strong denaturation of protein-G and IgG.
- Magnetic tweezers are sensitive to local changes of the binding between proteins.