Characterization of the engineered strain. (a) Schematic representation of the genotype at the engineered locus is shown for MC1061 negative control, BW27783 parent strain, and MK01 derived strain. (b) This panel shows PCR verification of engineered strain using different primer pairs for negative, parent and derived strains as templates. Left panel shows PCR amplicons resulting from the primers specific to the flanking regions, whereas the middle and right panel show the primers specific to the flanking and inserted selection cassette. Marker bands are shown in bps. (c) Western blot of parent and engineered strains using anti-LacI antibody is displayed. Maker bands are shown in kDa. (d) This panel shows results of a competition assay, showing the percentage of the parent and engineered strains after mixing them at equal ratios and growth during 15 hours. The data were taken using flow cytometry and labeling of the two strains with different fluorescent markers. (e) Same as (d), but with swapped fluorescent reporters: BW27783-mCherry and MK01-eYFP.