Table 1. Incubation conditions of the reference biofilm cultures (Ref 300N-23C) exposed for a short period to specific environmental conditions.
| Name | NO3−/NO2− mg-N/L (mM) | Methanol % (v/v) | C/N | NaCl % (w/v) | pH | Temp C |
|---|---|---|---|---|---|---|
| Tested conditions | ||||||
| NO3− and methanol (C/N=1.5). Exposure: 12–48 h | ||||||
| 300N−NO3-0.15%MeOHa | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| 600N−NO3-0.3%MeOH | 600 (42.8) | 0.3 | 1.5 | 2.75 | 8.0 | 23 |
| 900N−NO3-0.45%MeOH | 900 (64.3) | 0.45 | 1.5 | 2.75 | 8.0 | 23 |
| 1500N−NO3-0.75%MeOH | 1500 (107) | 0.75 | 1.5 | 2.75 | 8.0 | 23 |
| 3000N−NO3-1.5%MeOH | 3000 (214) | 1.5 | 1.5 | 2.75 | 8.0 | 23 |
| NO2−. Exposure: 12–48 h | ||||||
| 400N−NO2 | 400 (28.6) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| 200N−NO2 | 200 (14.3) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| 200N-NO3/200N−NO2 | 200+200 (28.6) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| Methanol (C/N variable). Exposure: 12–48 h | ||||||
| 0%MeOH | 300 (21.4) | 0 | 0 | 2.75 | 8.0 | 23 |
| 0.05%MeOH | 300 (21.4) | 0.05 | 0.5 | 2.75 | 8.0 | 23 |
| 0.15%MeOHa | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| 0.5%MeOH | 300 (21.4) | 0.5 | 5 | 2.75 | 8.0 | 23 |
| NO3−. (C/N variable): Exposure: 12–48 h | ||||||
| 90N−NO3 | 90 (6.4) | 0.15 | 5 | 2.75 | 8.0 | 23 |
| 300N−NO3a | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| 900N−NO3 | 900 (64.3) | 0.15 | 0.5 | 2.75 | 8.0 | 23 |
| 3000N−NO3 | 3000 (214) | 0.15 | 0.15 | 2.75 | 8.0 | 23 |
| pH**. Exposure 48–120 h | ||||||
| pH4 | 300 (21.4) | 0.15 | 1.5 | 2.75 | 4.0 | 23 |
| pH6 | 300 (21.4) | 0.15 | 1.5 | 2.75 | 6.0 | 23 |
| pH8* | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| pH10 | 300 (21.4) | 0.15 | 1.5 | 2.75 | 10.0 | 23 |
| Temperature**. Exposure 48–120 h | ||||||
| 5 °C | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 5 |
| 15 °C | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 15 |
| 23 °C* | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| 30 °C | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 30 |
| 36 °C | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 36 |
| NaCl**. Exposure 48–120 h | ||||||
| 0%NaCl | 300 (21.4) | 0.15 | 1.5 | 0 | 8.0 | 23 |
| 1%NaCl | 300 (21.4) | 0.15 | 1.5 | 1.0 | 8.0 | 23 |
| 2.75%NaCla | 300 (21.4) | 0.15 | 1.5 | 2.75 | 8.0 | 23 |
| 5%NaCl | 300 (21.4) | 0.15 | 1.5 | 5.0 | 8.0 | 23 |
| 8%NaCl | 300 (21.4) | 0.15 | 1.5 | 8.0 | 8.0 | 23 |
Notes.
The ASW medium was adjusted for specific concentrations of methanol (MeOH), NO3−, NO2− and NaCl, and pH. The biofilm carriers from the reference biofilm cultures were transferred in these solutions and incubated under the prescribed temperature. The 200N-NO3-200N-NO2 assays were done with a mix of 200 mg NO3−-N/L and 200 mg NO2−-N/L. In gray are parameters different from those of the reference biofilm cultures. C/N: Carbon Nitrogen ratio. A 1.5 C/N ratio corresponds, for instance, to 300 mg NaNO3-N/L (21.4 mM) and 450 mg CH3OH-C/L (37.5 mM or 0.15% v/v). All assays were carried out in triplicates, except the NO2-assays (one replicate). See Fig. S2 for more details.
Reference biofilm cultures.
The reference biofilm cultures were incubated in the prescribed conditions for two days, and then transferred in fresh medium for 12 to 72 h.