Contrary to the AbIC IΔblp1 mutant,

Contrary to the AbIC IΔblp1 mutant, the AbIC IIΔblp1 strain showed no alterations in the initialattachment compared to the parent, evident through the lack of PI-stained bacteria and through the formation of more uniform biofilm structure similar to parental strain (Fig. 2a, lower panels). To verify that the observed phenotype of AbIC IΔblp1 was indeed blp1-dependent, we introduced plasmids pblp1IC I and pblp1IC II carrying respective blp1 alleles into AbIC IΔblp1 bacteria and assessed their attachment to the plastic surface. Notably, both blp1 alleles efficiently restored the phenotype of AbIC IΔblp1 mutant manifested by the reduction in PIstained cells compared to the AbIC IΔblp1 mutant carrying control plasmid (Fig. 2b and Additional file 3: Figure S2).