Biofilm formation by seaweed-associated bacteria: Images

Biofilm formation by bacteria can be detected by cultivating the organism in a liquid medium, dispensing the bacterial growth into a 96-well plate, and after an overnight incubation, can be tested for biolfim formation. The 96-well plate is typically rinsed with water, followed by a treatment with the dye, crystal violet, giving a deep purple colouring. Biofilm_TSB_Plate 1: Image of the 96-well plate, Plate 1, taken from above to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density. Strains were cultivated in tryptic soy broth (TSB).Biofilm_TSB_Plate 1_side view: Image of the 96-well plate, Plate 1, taken from the side to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density. Indicators of biofilm formation include a ring formation in a well (visible as a line in the centre of the well), or a precipitate seen at the base of the well. Strains were cultivated in TSB.Biofilm_TSB_Plate 2: Image of the 96-well plate, Plate 2, taken from above to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density. Strains were cultivated in TSB.Biofilm_TSB_Plate 2_side view: Image of the 96-well plate, Plate 2, taken from the side to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density. Indicators of biofilm formation include a ring formation in a well (visible as a line in the centre of the well), or a precipitate seen at the base of the well. Strains were cultivated in TSB.Biofilm_TSB+_Plate 1: Image of the 96-well plate, Plate 1_TSB+ (strains cultivated in the presence TSB prepared in a commercial Red Sea salts solution), taken from above to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density.Biofilm_TSB+_Plate 1_side view: Image of the 96-well plate, Plate 1_TSB+ (strains cultivated in the presence TSB prepared in a commercial Red Sea salts solution), taken from the side to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density. Indicators of biofilm formation include a ring formation in a well (visible as a line in the centre of the well), or a precipitate seen at the base of the well.Biofilm_TSB+_Plate 2: Image of the 96-well plate, Plate 2_TSB+ (strains cultivated in the presence TSB prepared in a commercial Red Sea salts solution), taken from above to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density.Biofilm_TSB+_Plate 2_side view: Image of the 96-well plate, Plate 2_TSB+ (strains cultivated in the presence TSB prepared in a commercial Red Sea salts solution), taken from the side to show the residual crystal violet staining prior to the addition of 30% (v/v) acetic acid to solubilise the crystal violet before measuring the optical density. Indicators of biofilm formation include a ring formation in a well (visible as a line in the centre of the well), or a precipitate seen at the base of the well.Summary graph of biofilm formation by seaweed isolates: PowerPoint slide containing the image of the summary graph of biofilm formation by the seaweed-associated bacteria when cultivated in TSB or TSB+. The raw data related to the summary graph, can be found in the Biofilm datasets uploaded.Layout of the 96-well plates:Plate 1 (TSB and TSB+) - wells 1A-1H: strain PCL16; 2A-2H: strain PCL5; 3A-3H: strain DEP6; 4A-4H: strain DEP8; 5A-5H: strain BS R1 E#2; 6A-6H: strain CAT2; 7A-7H: Media controlPlate 2 (TSB and TSB+) - wells 1A-1H: strain DEP17; 2A-2H: strain SJ2 SW3; 3A-3H: strain SJ2 F1; 4A-4H: strain BS S1 E#1; 5A-5H: strain SJ1 R4; 6A-6H: strain SJ1 F24; 7A-7H: Media control