Figure 1. A schematic of the generation of P. aeruginosa knockout mutant PAO1 ΔCΔ8ΔF.

In order to promote the production of PHA_MCL inclusions and vaccine candidate EPS Psl, site-directed homologous recombination was used to delete major parts of (a) alg8 and (b) pelF genes encoding a glycosyltransferase in the PHA negative mutant PAO1 ΔphaC1ZC2. (c) Resultant triple mutant strain is defective in PHA/alginate/pel polysaccharide was verified by DNA sequencing (see Supplementary Fig. 1).