FIG. 1.

(A) Effect of inactivation of EpsR on expression from different EPS genes. Cells used were grown to an OD₆₀₀ of 1.5 and then assayed as described previously (29, 30). The bars represent an average of three independent trials. (B) Effect of the epsRΩ mutation on expression from the epsI promoter at different cell densities. Cells used for the assay were collected at the indicated optical densities and then frozen at −70°C until use. β-Galactosidase activities (micromoles of ONPG [o-nitrophenyl-β-d-galactopyranoside] hydrolyzed per minute per milligram of protein) were determined and plotted.