Table 4.
Substrate specificities of the AHL-acylase Aac against AHLs
| AHL-acylase activities (nmol·min-1·ml-1)a | ||
|---|---|---|
| AHLs | E. coli DH10B (pBBR1MCS-3) |
E. coli DH10B (pS3aac) |
| C4-HSL | 0.26 ± 0.15 (7.2%) | 0.37 ± 0.13 (10.3%) |
| C6-HSL | 0.31 ± 0.15 (8.7%) | 0.38 ± 0.10 (10.5%) |
| 3OC6-HSL | 0.37 ± 0.09 (10.5%) | 0.35 ± 0.09 (10.5%) |
| C7-HSL | 0.23 ± 0.15 (6.4%) | 3.60 ± 0.31 (100.0%)* |
| C8-HSL | 0.21 ± 0.16 (5.7%) | 1.63 ± 0.21 (45.4%)* |
| 3OC8-HSL | 0.22 ± 0.17 (6.1%) | 2.56 ± 0.04 (71.1%)* |
| C10-HSL | 0.25 ± 0.15 (7.1%) | 3.10 ± 0.25 (86.1%)* |
a Values represent the averages ± standard errors from triplicate independent HSL-OPA assays. The relative activity in parentheses is based on defining C7-HSL-degrading activity exhibited by E. coli DH10B (pS3aac) as 100%. The value with an asterisk (*) is the significant difference from the E. coli DH10B (pBBR1MCS-3) shown in the same row by one-tailed Student's t-test (P < 0.05)