Table 3.
Comparison of Chi18H8 production and IB solubilization in 2 L flasks, 3 L bench-bioreactor or 30 L industrial-bioreactor
| Cell weight (gcell/L) | Chi18H8 production (mg/gcell) | Solubilization yield (%) | Specific activity (U/mgprotein) | |
|---|---|---|---|---|
| Flask | 4.0 | 9.4 | >80 | 40.7 |
| 3 L bench-bioreactor | 5.3 | 9.1 | >65 | 52.1 |
| 30 L industrial-bioreactor | 6.2 | 12.9 | >65 | 48.4 |
Protein expression was induced in the early exponential growth phase (OD600nm ~0.6) with 0.4 mM IPTG and cells were harvested after 24 h of incubation. Chi18H8 production (mg protein/g cell) and solubilization yield in 10 mM lactic acid were estimated by densitometric analysis of proteins separated by SDS-PAGE. Specific activity of the solubilized enzyme was measured by the fluorimetric assay on 4-MU-(GlcNAc)2