Table 6.
Cell dry weight, PHA production, and monomer composition of PHA produced by A. vinelandii ΔAvin_16040 mutant strain, C. necator PHB−4, and C. necator Re2058 transconjugants.
| Strain 1 | Concentrations of Na4HB (g/L) | Cell Dry Weight (g/L) 2 | PHA Content (%) 3 | PHA Concentration (g/L) 4 | Monomer Composition (mol.%) | |
|---|---|---|---|---|---|---|
| 3HB | 4HB | |||||
| A. vinelandii ΔAvin_16040 mutant strain | 2 | 4.0 ± 0 e | 54 ± 1 d | 2.2 ± 0 e | 90 ± 0 | 10 ± 0 |
| 4 | 3.5 ± 0 d | 48 ± 0 c | 1.7 ± 0 d | 87 ± 0 | 13 ± 0 | |
| 6 | 3.0 ± 0.1 c | 42 ± 1 bc | 1.3 ± 0 c | 84 ± 0 | 16 ± 0 | |
| 8 | 2.5 ± 0.1 b | 36 ± 0 ab | 0.9 ± 0 b | 80 ± 0 | 20 ± 0 | |
| 10 | 2.0 ± 0.1 a | 34 ± 3 a | 0.7 ± 0 a | 78 ± 0 | 22 ± 0 | |
| No precursor | 4.3 ± 0.1 f | 55 ± 2 d | 2.4 ± 0 f | 100 ± 0 | 0 | |
| C. necator PHB−4 containing phaC of A. vinelandii mutant cell | 0.5 | 3.7 ± 0 a | 40 ± 3 a | 1.5 ± 0.1 a | 95 ± 0 | 5 ± 0 |
| 1 | 3.8 ± 0 ab | 43 ± 2 ab | 1.6 ± 0.1 ab | 94 ± 0 | 6 ± 0 | |
| 1.5 | 4.0 ± 0 bc | 46 ± 2 ab | 1.8 ± 0.1 ab | 93 ± 0 | 7 ± 0 | |
| 2 | 4.0 ± 0 c | 49 ± 3 b | 2.0 ± 0.1 b | 93 ± 0 | 7 ± 0 | |
| 2.5 | 4.0 ± 0 bc | 45 ± 1 ab | 1.8 ± 0 ab | 93 ± 0 | 7 ± 0 | |
| No precursor | 4.9 ± 0.1 d | 62 ± 2 c | 3.0 ± 0.2 c | 100 ± 0 | 0 | |
| C. necator Re2058 containing phaC of A. vinelandii mutant cell | 0.5 | 4.3 ± 0.1 b | 45 ± 2 a | 2.0 ± 0.1 a | 100 ± 0 | 0 |
| 1 | 4.6 ± 0 c | 49 ± 0 b | 2.3 ± 0 b | 97 ± 0 | 3 ± 0 | |
| 1.5 | 4.7 ± 0 cd | 50 ± 1 b | 2.3 ± 0.1 bc | 97 ± 0 | 3 ± 0 | |
| 2 | 4.8 ± 0 de | 51 ± 0 b | 2.5 ± 0 cd | 96 ± 0 | 4 ± 0 | |
| 2.5 | 5.0 ± 0 e | 53 ± 1 b | 2.6 ± 0.1 d | 95 ± 0 | 5 ± 0 | |
| No precursor | 4.0 ± 0 a | 45 ± 1 a | 1.8 ± 0 a | 100 ± 0 | 0 | |
Data shown are means of triplicate. The superscripts represent the significant difference of the data using statistical analysis (p < 0.05) for each bacterial strain. Superscript alphabets for each column that are different indicate a significant difference.1 A. vinelandii ΔAvin_16040 mutant strain and the transconjugants were cultivated using 30 g/L of fructose and 0.54 g/L of urea at 30 °C with agitation speed of 200 rpm. A. vinelandii ΔAvin_16040 mutant strain was cultivated for 72 h while the transconjugants were cultivated for 48 h. Different concentrations of Na4HB were used. ‘No precursor’ indicates no addition of precursor in the medium. 2 Cell dry weight was obtained after freeze-drying process. 3 PHA content of freeze-dried cell was determined using gas chromatography. 4 PHA concentration = cell dry weight * (PHA content/100).