The resulting model predictions can then be compared against our observed data. The exact model predictions for both the plaque size and plaque productivity are listed in the Additional file 1. Since virion find more morphology is likely to impact plaque formation (see above), we only conducted comparisons

within each morphology group, using the wt λstf + or the wt λstf – as the denominators for the ratio comparisons. For both the Stf+ (Figure 4A) and Stf- (Figure 4C) phages, the observed ratios of plaque radii–obtained as the ratios of the square roots of the determined plaque surface areas–did not vary greatly with the adsorption rate. However, except for Eqn. 5, and Eqn. 2 (see Appendix) when in high adsorption rate, both of which predicted a declining ratio as adsorption rates increased (Figure 4A). However, all other models listed in the Appendix failed to predict observed ratios of plaque radii. The failure is especially prominent when the adsorption rate is low, i.e. for the Stf- phages (Figure 4C). Figure 4 Observed and expected ratios of plaque radius and plaque productivity. Ratios of plaque radii (A, C, and E) and plaque productivity (B, D, and F) are plotted against adsorption rate (A – E) or lysis time (E and F). Solid lines and numbers showed Selleck EGFR inhibitor the model predictions from equations listed in Table A.2. Filled circles denote observed ratios from the Stf+ phages and open circles the Stf- phages. Plus and minus

signs next to the numbers indicate Stf+ phages and Stf- phages, respectively. All values are compared against those of the wild type λ, with or without the Stf. Error bars denote the 95% confidence intervals of the observed ratios (see Methods). For isogenic phage strains that differed in their lysis times (and burst sizes), the ratios of plaque radii also showed the same peaked pattern (Figure 4E) shown in Figure 2D. Interestingly, both the Stf+ and Stf- phages showed the same ratios of plaque radii, even though the Stf+ phages generally

have significantly smaller plaque sizes (Figure 2A). Furthermore, unlike the above result, Eqn. 3 seemed to perform reasonably well in predicting ratios of plaque radii, at least when the lysis time is shorter than 52.3 min. All the models predicted a larger ratio than observed when the lysis time is Parvulin longer than 52.3 min. As the adsorption rate increases, the observed ratios of plaque productivity declined to a similar degree for both the Stf+ (Figure 4B) and Stf- (Figure 4D) phages. However, except for Eqn. 5, which performed superbly when the adsorption rate is low (Figure 4D), none of the other models can reasonably predict the observed ratios. As before, the failure is more prominent when the adsorption rate is low. For the strains with different lysis times, both the Stf+ and Stf- phages showed an almost identically complex pattern, except when the lysis time is very long or very short (Figure 4F).