Figure 1.

Schematic representation of screening assay of DNA–protein interaction with solid-phase single-molecule PCR in w/o emulsions. 1: Target DNA mixture diluted as <1 molecule per compartment on average. The diluted DNA template solution was added to the PCR mixture including oligonucleotide-coupled beads. Subsequently, the aqueous phase is gradually added to the oil phase with stirring using a magnetic bar for 3 min at room temperature and solid-phase single-molecule PCR in w/o emulsions is carried out. 2: The emulsions are disrupted. 3: A DNA-binding protein with epitope tag is added to the beads. 4: A fluorescence-labeled anti-tag antibody is added to the complex. 5: Flow cytometry for selecting positive clones and multibead PCR with selected beads. 6: Flow cytometry for selecting positive clones and bead PCR with selected beads. 7: Gel mobility shift assay.