Figure 4. Round-by-round read counts for the enriched FLAG motifs. Sequence reads from initial library (0th) to 3rd round selection, 4th round with competitive elution with FLAG epitope tag at 4, 20, 100 μg/ml concentration and remaining beads are counted for (A) DYKDDDDK, (B) DYKDDDxx, (C) xDYK(D/L/N)(D/F/L/N/Y)Dxxx and (D) xxxxDYK(D/L/N)(D/F/L/N/Y)D sequences. For each round, read counts for mRNA display method (orange) and cDNA display (dark blue) are presented side-by-side.