SDS-PAGE analysis of the recombinant P. pastoris revealed ~ 42 kDa SAM synthetase protein, from 12-90 h induction, with maximum expression of recombinant SAM synthetase from 48-60 h.
After induction, the maximum fold expansion for accumulated megakaryocytes was almost 5000-fold, and the induced megakaryocytes were characterized by analysis of gene expression, polyploidy and platelet activation ability.
Hypoxic conditions also significantly increased IL-8 mRNA expression but exhibited a more delayed induction, reaching maximum up-regulation after 8 to 24 hours (P < 0.01).
Cell densities before induction and maximum growth rates on glycerol were very similar and similar to those previously reported in P. pastoris [ 33, 35].
Upon methanol induction, the maximum α-amylase activity and protein concentration produced by recombinant strain GS115 carrying BlAmy-opt reached 8100 U/mL and 8.3 g/L, respectively, in the 5-L fed batch bioreactor).
The formation temperature, maximum induction temperature and induction time are measured.
The maximum induction appeared in about 20 min. Conversely, the induction process was much slower under low light illumination (10 µmol photons m−2 s−1).
Besides maximum induction, in one case we induced using 5% of the concentrations needed for maximum induction (weak induction), and in another with 15% (medium induction).
During the stationary phase, when cell growth reached its maximum, induction is not desired, since expression rate is proportional to the growth rate at the induction moment.
