The optimum expression of the fusion protein was found to be at 4 h after induction (Fig. 1, lane 3).
Compared with TSB or CCY culture media, brain-heart infusion media (BHI) supported optimum expression of hlgA transcript (Fig. 6A).
Codon optimization, a genetic technique used to achieve optimum expression of a foreign gene in a host's cell system is achieved by replacing existing codons of a specie with a set of more suitable host codons [31] [34].
FOXA1, a forkhead family transcription factor, is essential for optimum expression of ER and estrogen responsive genes.
To obtain optimum expression of foreign RparsM gene in the P. putida KT2440 strain, we compared the codon usages of RparsM to P. putida.
SDS-PAGE analysis demonstrated that optimum expression of proteins was observed at 25°C using 0.8 mM IPTG after 6 8 h of induction.
Taken together these results suggest that activation of p38-MAPK is responsible for the optimum expression of IL-6, IL-8 and TNF-α in IL-1β-stimulated OA chondrocytes, while JNK appeared to be critical for the expression of IL-6 but not for IL-8 and TNF-α in IL-1β-stimulated OA chondrocytes.
This approach allows us to measure both the cost and benefit of lac operon expression for independently varying levels of inducer and carbon source, and to directly determine the optimum expression level of the metabolic genes for each carbon source concentration.
Moreover, the decoupling allows one to study the evolution of regulated expression in a controlled way; by establishing environments in which the wild-type lac regulation is suboptimal (the level of gene expression set by induction does not match the optimum expression level demanded by the amount of carbon source in the environment).
Our results also demonstrate that some chemokines require the activation of p38-MAPK for optimum expression.
