Protein analysis by time-resolved measurements with an electro-switchable DNA chip

Area of Science:

• Biophysics
• Nanotechnology
• Biochemistry

Background:

• Traditional protein analysis often requires separate stationary and mobile phase measurements.
• Immobilizing proteins allows parallel analysis but infers properties from mobility, limiting comprehensive characterization.
• Existing methods necessitate multi-step workflows for complete protein analysis.

Purpose of the Study:

• To reconcile stationary and mobile phase measurement modalities in protein analysis.
• To develop a method for accurate protein diameter quantification and detection of structural alterations.
• To enable comprehensive protein characterization through a unified workflow.

Main Methods:

• Tethering proteins to a surface using dynamically actuated nanolevers.
• Employing short DNA strands as capture probes, switched by alternating electric fields.
• Quantifying protein diameter by analyzing motional dynamics against a theoretical model.

Main Results:

• Protein diameter quantified with Angström accuracy.
• Alterations in tertiary protein structure (folding) and conformational changes readily detected.
• Post-translational modifications revealed through time-resolved molecular dynamics measurements.

Conclusions:

• The developed nanolever technique successfully integrates different measurement principles for protein analysis.
• This method offers high accuracy in determining protein dimensions and sensitivity to structural changes.
• It provides a powerful tool for detailed protein characterization, including modifications.