Fig. 2 Phage pool ELISA analysis. (a) Samples (MBP/GST-tagged bait proteins)
and their negative controls (MBP/GST) are immobilized side-by-side in a 96-well
plate, and incubated with binding enriched phage pools. Unbound phage is
washed away and the bound phage is detected by an HRP-linked M13
antibody. (b) The progress of the selection is evaluated by comparing the ratio
of the ELISA signal of the bait protein and the negative control over the days of
selection. The ratio between bait and reference signal should be at least 2 for a
selection to be considered successful. Here, bait 1 represents a successful
selection, where the ELISA signals from selection day 2, 3, and 4 suggest that
the number of phages bound to the bait protein surpasses the number bound to
the reference by several folds. Bait 2 represents an unsuccessful selection
56
Susanne Lu ¨ chow et al.
and their negative controls (MBP/GST) are immobilized side-by-side in a 96-well
plate, and incubated with binding enriched phage pools. Unbound phage is
washed away and the bound phage is detected by an HRP-linked M13
antibody. (b) The progress of the selection is evaluated by comparing the ratio
of the ELISA signal of the bait protein and the negative control over the days of
selection. The ratio between bait and reference signal should be at least 2 for a
selection to be considered successful. Here, bait 1 represents a successful
selection, where the ELISA signals from selection day 2, 3, and 4 suggest that
the number of phages bound to the bait protein surpasses the number bound to
the reference by several folds. Bait 2 represents an unsuccessful selection
56
Susanne Lu ¨ chow et al.