High spatiotemporal resolution data from a custom magnetic tweezers instrument

Area of Science:

• Biophysics
• Molecular Biology
• Biochemistry

Background:

• Gene expression relies on enzymes like RNA polymerases that move along nucleic acids with precise, small steps.
• Understanding these complex biochemical pathways necessitates high spatiotemporal resolution techniques.
• Magnetic tweezers offer a powerful single-molecule force spectroscopy method for observing these processes.

Purpose of the Study:

• To present data from a bespoke magnetic tweezers instrument designed for high throughput or high resolution.
• To benchmark the best achievable resolution for DNA-tethered magnetic beads and surface-attached beads.
• To highlight the impact of mechanical stability on assay performance.

Main Methods:

• Utilizing a custom-built magnetic tweezers instrument with advanced camera-based detection.
• Performing single-molecule force spectroscopy on DNA-tethered magnetic beads.
• Analyzing data for subnanometer step detection along the z-axis.

Main Results:

• The instrument demonstrates high spatiotemporal resolution, achieving subnanometer precision.
• Data shows the capability to detect 0.34 nm steps along the z-axis using DNA tethered magnetic beads.
• Mechanical stability's influence on assay resolution was investigated and highlighted.

Conclusions:

• The presented data aligns with the best resolutions achieved by magnetic tweezers.
• This work provides a valuable benchmark for the adjustment and optimization of magnetic tweezers setups.
• The findings contribute to a better understanding of molecular mechanisms in gene expression.