FIG. 6.

GelE degrades polymerized fibrin. (A) Complete fibrin degradation by the supernatants of strains that express GelE at 24 h. Cultures were grown overnight in the presence of 25 ng of nisin per ml at 37°C, with the exception of well 7, which was grown at 30°C. The supernatants of these cultures were filtered with a 0.45-μm-pore-size syringe tip filter, and a equal volume was added to the polymerized fibrin (time zero). Wells: 1, OG1RF (GelE⁺ SprE⁺); 2, TX5128 (GelE⁻ SprE⁻); 3, TX5264 (GelE⁻ SprE⁺); 4, TX5243 (GelE⁺ SprE⁻); 5, TX5128(3614); 6, TX5264(3614); 7, OG1RF grown at 30°C. (B) The rate of fibrin degradation was also measured by determining the decrease in OD₆₃₀ of the wells after addition of culture supernatants over the course of 24 h. A representative time course of fibrin degradation is shown. (C) GelE expressed heterologously in L. lactis NZ9800 degrades fibrin at 24 h.