FIG. 3.

aidH is the sole Ochrobactrum sp. T63 gene involved in AHL-degrading activity. (A) N-(3-Oxooctanoyl)-l-homoserine lactone (OOHL) was incubated with the wild-type, the aidH deletion mutant, or the complementation strain. Culture supernatants were extracted, and the AHLs were detected by the biosensor A. tumefaciens NTL4(pZLR4) as described in Materials and Methods. Error bars denoting standard deviations from three experiments are shown. (B) Plate assay of samples described above (A). The extracts were spotted onto an ABM minimal medium plate seeded with an A. tumefaciens NTL4(pZLR4) culture and X-Gal (40 μg/ml) and incubated at 28°C for 16 h. The control was an OOHL standard (10 pmol).