TABLE 2.
PHA production by nuclease integrants of Pseudomonas sp. strain MBX978 in minimal E2 medium with 10 mM octanoate as the carbon source
| Strain | Nuclease activitya | A600b | tdc (h) | % PHAd
|
||
|---|---|---|---|---|---|---|
| C6 | C8 | Total | ||||
| MBX978 | ND | 3.7 | 1.5 | 4.2 | 29.2 | 33.4 |
| MBX979 | +++ | 3.6 | 1.6 | 3.8 | 26.0 | 29.8 |
| MBX981 | + | 3.4 | 1.4 | 4.0 | 27.9 | 31.9 |
| MBX982 | + | 3.5 | 1.6 | 4.0 | 27.1 | 31.1 |
| MBX984 | ++ | 2.8 | 1.6 | 1.5 | 12.2 | 13.8 |
| MBX985 | ++ | 3.8 | 1.4 | 4.1 | 28.3 | 32.4 |
a
Relative activity was estimated by chromosomal DNA digestion followed by agarose gel electrophoresis as described in Materials and Methods. The sizes of resulting DNA fragments are noted as follows: 200 to 300 bp, +++; 400 to 1,000 bp, ++; 500 to 4,000 bp, +; or no degradation, ND.
b
Optical density at 600 nm after 24 h of growth, at which point cells were harvested for PHA analysis.
c
Doubling time (± 0.1 h).
d
Accumulated levels of 3-hydroxyhexanoate (C6), 3-hydroxyoctanoate (C8), and total PHA as percentages of cell dry weight (total PHA is ±5%).