Fig. 4: Application of EPR E. coli strains in phage-rich flask-shaking or fed-bath recombinant protein production.

a Flow chart of EPR E. coli strains applied in recombinant protein production. b-d Flask-shaking recombinant protein production characteristics of the wild-type and EPR E. coli strains when infected or not infected with phage cocktail. WT-MG1655 and MG1655-EPR strains producing DAAO (b), WT-W3110 and W3110-EPR strains producing DAAO (c), and WT-MG1655 (DE3) and MG1655 (DE3)-EPR strains producing nsp8 (d) are shown. Phage cocktail was added at the start of cultivation. Values represent the mean of three biological replicates, and error bars represent standard deviations (dots). Statistical significance was calculated by one-way ANOVA followed by Tukey’s test. ns, not significant. e–g Average fed-batch fermentation profile of the wild-type and EPR E. coli strains when infected or not infected with phage cocktail. WT-MG1655 and MG1655-EPR strains producing DAAO (e), WT-W3110 and W3110-EPR strains producing DAAO (f), and WT-MG1655 (DE3) and MG1655 (DE3)-EPR strains producing nsp8 (g) are shown. Phage cocktail was added at the start of fermentation (black arrow), and IPTG was added when the OD₆₀₀ reached 20 (red arrow). Values represent the means of duplicate fermentation profiles. Source data are provided as a Source Data file.