Table 5. Concentrations of the strains JAM1 and NL23 in the reactors determined by qPCR.
| Suspended biomass | Biofilm | Totala cp/reactor (x109) | Specific ratesb (µM-NOx h−1) per 109 gene copies | |||||
|---|---|---|---|---|---|---|---|---|
| cp gene/mL (x107) | Proportion of NL23 % | cp/gene support (x107) | Proportion of NL23 % | |||||
| JAM1 | NL23 | % | JAM1 | NL23 | ||||
| Reactor 1 | ||||||||
| Biofilm co-culture | ||||||||
| 0.5% | 13.2 (28.0) | 0.86 (0.90) | 6.1 | Nm | Nm | |||
| 1.0% | 1.1 (1.6) | 0.30 (0.11) | 21.4 | Nm | Nm | |||
| 2.0% | 1.5 (0.5) | 0.21 (0.15) | 12.3 | Nm | Nm | |||
| 2.75% | 5.0 (1.3) | 0.12 (0.10) | 2.3 | Nm | Nm | |||
| IO no sup | 42.9 (3.7) | 0.34 (0.2) | 0.78 | Nm | Nm | |||
| IO + sup | 51.5 (54.6) | 0.32 (0.30) | 0.62 | 56.1 | 8.5 | 1.9 | 453 | 1.9 |
| Reactor 2 | ||||||||
| Biofilm co-culture | ||||||||
| 0.5% | 60.9 (16.5) | 2.7 (0.96) | 4.2 | 92.8 | 11.4 | 10.9 | 621 | 1.42 |
| 1.0% | 46.2 (12.6) | 2.9 (0.83) | 5.9 | Nm | Nm | |||
| 2.0% | 23.3 (4.2) | 0.42 (0.15) | 1.8 | Nm | Nm | |||
| 2.75% | 14.4 (0.9) | 0.19 (0.09) | 1.3 | 262 | 12.8 | 4.7 | 796 | 2.75 |
| IO + sup | 5.2 (4.6) | 0.16 (0.08) | 3.0 | Nm | Nm | |||
| IO no sup | 10.5 (15.3) | 0.13 (0.17) | 1.2 | 182 | 8.1 | 4.3 | 554 | 1.62 |
| Reactor 3 | ||||||||
| Strain NL23 biofilm mono-culture | ||||||||
| 0% | NA | 6.7 (3.2) | NA | Nm | ||||
| 0.5% | NA | 2.7 (1.4) | NA | 23.3 | 76 | 36.1 | ||
| 1.0% | NA | 2.0 (0.86) | NA | 15.4 | 51 | 52.7 | ||
| 2.0% | NA | 1.0 (0.59) | NA | 8.2 | 27 | 19.6 | ||
Notes.
Genes, napA for strain NL23; narG1 for strain JAM1. cp, copies. Values between parentheses are standard errors.
a
Determined by the multiplication of the gene copies/mL of both strains by 550 mL (volume of the reactor) plus the multiplication of the gene copies per support of both strains by 260 supports.
b
Specific rates were calculated by the division of the NOx reduction rates (Table 4) by the gene copies/reactor.
Nm, No measurement was carried out; NA, not applicable.