Single-molecule mechanics of protein-labelled DNA handles

• Vivek S. Jadhav,
• Dorothea Brüggemann,
• Florian Wruck and
• Martin Hegner

Beilstein J. Nanotechnol. 2016, 7, 138–148, doi:10.3762/bjnano.7.16

• here demonstrate that handles produced with our protein–DNA labelling procedure are excellent candidates for grasping single molecules exposing tags suitable for molecular recognition in time-critical molecular motor studies. Keywords: DNA handles; optical tweezers; protein labels; single molecule

• experiments for both protein labels. With DTT buffer the interaction rate was only 53% for neutravidin-DNA and 61% for streptavidin-DNA, and bead clusters were observed in 20–35% of the experiments. A nominal ratio of 40:1 enabled efficient single molecule force measurements (90%) with the complete protein

• -labelled DNA construct against biotinylated beads (Figure 1a). Rupture forces were analysed in all buffers for DHs with streptavidin or neutravidin labels, respectively. Rupture force distributions for both protein labels are shown in Figure 4. The rupture force distributions for both protein–DNA