Optimal protein yield with the S30 T7 High-Yield Protein Expression System relies on a number of variables including: having a suitable expression vector, using a high-quality DNA template, adding the right amount of template to the reaction, and finding the best reaction time and temperature for your protein. Genetic manipulations of the protein-coding sequence, such as codon usage, truncation/domain and fusion tags can also be explored.
Promega Notes 101, 10-12.
Kate Qin Zhao and Don Creswell