FIG. 2.

Degradation of CGP in liquid and solid media. (A) Four anaerobic Hungate tubes, which contained initial concentrations of 1 g liter⁻¹ CGP plus 0.5 g liter⁻¹ yeast extract in 10 ml BM, after incubation at 30°C for 15 days. Tube 1 contains P. alcaligenes strain DIP1 and shows CGP degradation after the first 48 h of incubation. Tubes 2, 3, and 4 contain E. casseliflavus strain ELS3, C. sulfidogenes strain SGB2, and P. odorifer strain PNF4, respectively. None of the three strains could degrade CGP. (B) Degradation halo by P. alcaligenes strain DIP1 appearing after 24 h of incubation on an aerobic CGP overlay agar plate. (C) Degradation halo by P. alcaligenes strain DIP1 appearing after 3 to 4 days of incubation on an anaerobic CGP overlay agar plate.