TABLE 2.
Growth characteristicsa and rates of methane production on methanol of the promoter swap strains
| mtaCB operons(s) | Mean ± SD |
|||
|---|---|---|---|---|
| Generation time (h) | Lag time (h) | Cell yield (OD600) | Sp actb | |
| All present | 11.4 ± 0.5 | 77 ± 3 | 0.77 ± 0.01 | 150 ± 3 |
| All deleted | NGc | NG | NG | NG |
| PmtaC1-mtaCB1 | 10.6 ± 0.5 | 29 ± 2 | 0.77 ± 0.01 | 165 ± 25 |
| PmtaC1-mtaCB2 | 14.3 ± 2.2 | 180 ± 7 | 0.82 ± 0.01 | 155 ± 5 |
| PmtaC1-mtaCB3 | 18.2 ± 1.1 | 152 ± 3 | 0.83 ± 0.01 | 143 ± 18 |
| PmtaC2-mtaCB1 | 14.0 ± 0.3 | 38 ± 3 | 0.80 ± 0.00 | 116 ± 15 |
| PmtaC2-mtaCB2 | 15.5 ± 0.6 | 110 ± 2 | 0.85 ± 0.00 | 80 ± 8 |
| PmtaC2-mtaCB3 | 12.4 ± 0.3 | 33 ± 3 | 0.80 ± 0.00 | 179 ± 6 |
| PmtaC3-mtaCB1 | NG | NG | NG | NG |
| PmtaC3-mtaCB2 | 54.4 ± 6.9 | 495 ± 43 | 0.72 ± 0.01 | 87 ± 3 |
| PmtaC3-mtaCB3 | 49.2 ± 4.1 | 288 ± 31 | 0.34 ± 0.03 | 89 ± 11 |
a
Growth was measured as described in Materials and Methods by using strains WWM1, WWM390, and WWM392 to WWM400. The lag time represents the time needed to reach one-half the maximum OD600. Values represent the means and standard deviations of triplicate measurements.
b
Activity is reported in mU (see the text). Values represent the means and standard errors of four independent measurements.
c
NG, no growth.