S. meliloti cell envelope polysaccharides affect NCR247 competitiveness differentially. (A) Competition index (CI) values for known LPS biosynthesis genes with competition disadvantage for PMB, (B) genes involved in succinoglycan biosynthesis in the order they act in the pathway, (C) KPS genes identified to affect NCR247 competitiveness, and (D) genes known to affect cyclic β-glucan biosynthesis and export are shown. The results for NCR247 (black bars) and PMB (gray bars) are shown for both biological replicates for each condition. The dashed lines indicate the cutoff CI values of ≤0.5 and ≥2, representing reduced and increased competitiveness, respectively.