The mutants’ impact on biofilm formation under different incubation conditions. Microaerobic, anaerobic, and ambient oxygen incubation conditions are abbreviated as “Micro”, “Ana” and “O2” respectively. Statistically significant (P < 0.05) differences are highlighted with * and indicate comparisons with the wildtype. The experiment was repeated three times independently and samples were tested in at least three replicates per experiment. Data are presented as mean ± standard error.