Fig. 3

Biofilm formation of Xac29–1, Xac29–1Δhfq and Xac29–1Δhfq-C on glass bottle surfaces after 3 days incubation. The results of the biofilm formation assays were quantified by measuring the absorbance of the crystal violet stain at 600 nm. The tests were repeated three times. The asterisks in horizontal data column indicate significant differences at P = 0.01 by t test