FIG. 6.

Competence-induced release of β-galactosidase from the LytC-deficient H5 strain during logarithmic growth. Samples were collected at different cell densities (OD₅₅₀s of 0.1 to 0.7) and induced to competence by adding 250 ng of CSP-1/ml (black columns). Both cell-free supernatants and cell lysates (cells and supernatants) were assayed for β-galactosidase activity. The amount of β-galactosidase present in the supernatants (estimated in Miller units) is given as a percentage of the total activity present in the cell lysates. Corresponding uninduced samples were run in parallel as negative controls (grey columns). The presented data are representative of results from three independent experiments.