Design Of Novel Magnetic Tweezers And Its Use For Studying DNA-Compacting Proteins

We developed a novel transverse magnetic tweezers that can apply force to single DNA molecules in the horizontal plane. We use a $\lambda $- DNA attached to a 2.8 $\mu $m superparamagnetic bead on both ends. We describe the tweezers in detail and present data validating its performance. We show that using a simple design complemented with image processing techniques, we can reliably measure changes in the DNA's extension suitable for studying the binding of proteins. We conclude with a discussion of our experiments on the binding mechanism of the protein mIHF that plays an important role in the infection pathway of tuberculosis.