Enhanced porcine interferon-α production by recombinant Pichia pastoris with a combinational control strategy of low induction temperature and high dissolved oxygen concentration

Porcine interferon-alpha (pIFN-alpha) production by recombinant Piano postoris with standard induction strategy at 30 degrees C often suffers problems such as low antiviral activity, long cells adaptation period, etc. To solve these problems, a combinational induction strategy by simultaneously controlling induction temperature at 20 degrees C and dissolved oxygen concentration (DO) over 50% was proposed and the relevant fermentation runs were conducted in a 51 bioreactor. With this control strategy, pIFN-alpha antiviral activity could be continuously enhanced and eventually reached a level of 3.62 x 10(7) IU/ml, which was about 16-fold of the maximum obtained when induction was clone at 20 degrees C but without DO control, and more than 100-fold of the maximum obtained with the standard induction strategy at 30 degrees C. The novel control strategy could enhance alcohol oxidase (AOX) activity and relieve oxygen supply limitation in oxidative phosphorylation reaction to accelerate ATP regeneration simultaneously. As a result, the metabolic flux towards pIFN-alpha synthesis was enhanced and the adaptation period was shortened, enabling the entire system to be operated in a most efficient way. (C) 2010 Elsevier B.V. All rights reserved.