Fig. 7. Biofilm formation is affected by different levels of McaS expression.
A. Growth assay shows increased biofilm formation in the presence of McaS overexpression. Overnight cultures of strains NM525, NM525 ΔcsgD::cat (GSO554), NM525 ΔflhDC::kan (GSO553) and NM525 ΔpgaA::kan (GSO570) with the indicated plasmids were diluted to an OD600 ~0.05 into 200 μl of fresh LB + amp + IPTG and grown at 25°C for 24 h in a 96-well microtiter plate. Planktonic cells were washed away and the amount of biofilm retained in the wells was determined by crystal violet staining and measuring absorbance at OD570 and normalizingby OD600. The image is representative of three independent experiments.
B. Growth assay shows decreased biofilm formation in strains lacking mcaS. Four independent cultures of wild type MG1655 or the isogenic ΔabgR-ydaL::kan mutant (GSO569) lacking chromosomal McaS were grown overnight in LB at 37°C. The cultures were diluted to an OD600 ~0.05 in 200 μl fresh LB, CFA or YESCA media and grown at 37°C for 24 h in a 96-well microtiter plate. The amount of biofilm formation was determined as in A. The image is representative of three independent experiments.