Fig 1.
Chemical structures of tested compounds.
CLC (A), CPC (B); PBI (C), SCAA (D), LEC (E), TOB (F) and MET (G).
Fig 2.
Effect of medium and culture conditions on the biomass of G. vaginalis biofilms.
(A) Biomass development in different media after 20 h and 40 h of growth. (B) Effect of glucose concentration and oxygen. Biofilm mass was determined by crystal violet staining. Mean and standard deviation from twelve replicate cultures are shown. (C) Aerobic growth (5% CO2) at 37°C in sBHIG was measured by crystal violet staining. For the 40 h mc value, the growth medium had been replaced by fresh medium after 20 h of incubation (mc = medium change).
Fig 3.
Effect of pH on growth of G. vaginalis in planktonic and biofilm culture.
(A) Planktonic growth in media adjusted to pH 7, 5.5, 5 or 4.5 measured via OD600nm (B) Biofilm formation after 20 h at pH 7 (20 h, pH 7) and after 40 h with a medium change after 20 h. After the medium change, the pH was either kept at pH 7 (40 h, pH 7), changed to pH 4.5 (40 h, pH 4.5) or buffered with citrate phosphate buffer (CPB) to pH 4.5 (40 h, pH 4.5 CPB). Biofilm formation was measured using colony forming units (CFUs). Mean and standard deviation from triplicate cultures are shown.
Fig 4.
Effect of test compounds on G. vaginalis biofilm mass and viability.
(A) antibiotics, (B) enzymes and peptides, (C) antiseptics and (D) tensides. Biofilm mass was determined by CV staining and is shown on the primary y-axis. Inhibition of biofilm viability [%] was measured via live/dead staining and is shown on the secondary y-axis. Mean and standard deviation from triplicate cultures are shown.
Fig 5.
Viability of G. vaginalis biofilms after treatment with an antibiotic, enzyme or tenside.
Live/dead staining of G. vaginalis biofilms treated with 0.1 mg/ml MET, 0.5 mg/ml LYS or 1 mg/ml SCAA is shown for the 20 h experiment and the 40 h experiment in comparison to the untreated control.
Fig 6.
Biofilm mass and viability after treatment with combinations of tensides and antibiotics.
Biofilm mass was determined by crystal violet staining, and inhibition of biofilm viability was determined by live/dead staining. The tenside SCAA (1 mg/ml) was combined with 25 mg/ml TOB, 0.1 mg/ml MET, 0.05 mg/ml CPC or applied alone and compared to the untreated control. Mean and standard deviation from triplicate cultures are shown.