FIG 5.
ΔcysL mutation inhibits expression of biofilm matrix genes. (A) Biofilm formation of Δspx and ΔyjbH mutants. (B) The ΔsrfA mutation has little or no effect on biofilm formation in in 2×SGG. (C) Surfactin does not restore biofilm formation to the ΔcysL mutant. The wild-type strain and ΔcysL mutants were grown in 2×SGG medium with 0.1 μg/ml surfactin. (D) ΔabrB and ΔsinR mutations restore biofilm formation to the ΔcysL mutant. (E) Effects of the artificial expression of biofilm matrix genes on biofilm formation of the ΔcysL mutant. Pspac-eps operon and Pspac-bslA strains were grown in 2×SGG medium with 1 mM IPTG. (F) Expression of the eps operon. epsH::pMutin strains harboring the eps-lacZ reporter were grown for 24 h on 2×SGG medium or modified 2×SGG (m2×SGG) medium with 5-bromo-4-chloro-3-indolyl-β-d-galactopyranoside (X-Gal). m2×SGG medium contains four times less nutrient broth than does 2×SGG medium. All photographs of biofilms were taken 48 h after inoculation.