TABLE 2.
Xylanase activity in the extracellular fraction of S. lividans 10-164 and ΔtatC mutant transformed with different plasmids
| Transformant | Signal peptide | Xylanase activity (IU/ml)a |
|---|---|---|
| IAF915B1 | Sec dependent | 90 ± 6 |
| IAF915B2 | Sec dependent | 76 ± 5 |
| IAF916B1 | Tat dependent | 32 ± 4 |
| IAF916B2 | Tat dependent | 52 ± 5 |
| IAF907-SB1 | Sec dependent | 256 ± 10 |
| IAF907-SB1ΔtatC | Sec dependent | 207 ± 8 |
| IAF907-TB2 | Tat dependent | 173 ± 6 |
| IAF907-TB2ΔtatC | Tat dependent | 18 ± 5 |
| IAF907-SB1TB2 | Sec and Tat dependent | 350 ± 12 |
| IAF907-SB1TB2ΔtatC | Sec and Tat dependent | 172 ± 4 |
| IAF907-SB1pATB2 | Sec and Tat dependent | 360 ± 15 |
| IAF907-SB1pATB2ΔtatC | Sec and Tat dependent | 167 ± 3 |
| IAF907-TB2pATB2 | Tat dependent | 251 ± 14 |
a
The activity was measured in the culture supernatants along the growth of the transformants. The activity after 144 h of incubation is reported. Activity is the average of three independent cultures. Growth was similar for all transformants of S. lividans 10-164 and for all transformants of the ΔtatC mutant as determined by the DNA content of the cultures (data not shown). However, in these conditions, the growth of S. lividans 10-164 transformants was 30% higher than that of ΔtatC transformants.