NBS microbiologists recently assisted researchers at the University of California in achieving a 140-fold increase in protein production from a recombinant strain of Pichia pastoris yeast. Top yields by the researchers thus far had been 1.4 mg/L of a throm-bomodulin fragment when culturing Pichia in shake flasks. By switching to a BioFlo 3000 fermentor, NBS scientists were able to overcome the two main problems which plagued earlier studies insufficient oxygen, and a temperature increase of as much as 25C generated by the organisms prolific growth. Although fermentors commonly achieve yields of ten or more times that of shakers, these extraordinary results were largely due to the unique capabilities inherent in the BioFlo 3000 fermentor.
An Ideal Pichia Culturing System
The versatile BioFlo 3000 batch, fed-batch and continuous fermentor offers several design advantages. Uniquely, this fermentor comes with a built-in two gas controller for optimizing dissolved oxygen (DO) during fermentation, (as well as a four-gas controller for use during cell culture). Using any of the systems four operating modes, agitation may be increased and/or pure oxygen added throughout the run to maintain the desired DO level.
Second, the vessels stainless-steel water-jacket provides superior heat induction capability. A PID controller regulates culture temperature for optimum protein production in this case at 30C.
In addition, five pumps provide programmable addition and harvesting functions, which
ensured tight control over methanol, antifoam and nutrient addition in these studies.
Furthermore, BioCommand, NBS proprietary Windows-based software can be used to
automate process control, log and graph data on-line, or optimize product yields. NBS will even
supply software control algorithm