Heavy labeling of recombinant proteins

Area of Science:

• Biotechnology
• Molecular Biology
• Protein Expression

Background:

• High costs associated with isotopic chemicals and heterologous protein production necessitate economical labeling methods.
• Ovine interferon-tau expression in Pichia pastoris requires efficient and cost-effective isotopic labeling.

Purpose of the Study:

• To develop an economical 15N/13C isotopic labeling strategy for Ovine interferon-tau production in Pichia pastoris.
• To evaluate different isotopic sources and feeding strategies to minimize costs.

Main Methods:

• Tested four protocols for Ovine interferon-tau expression in Pichia pastoris.
• Evaluated 13C-glucose instead of 13C-glycerol and optimized 15N/13C-source addition timing.
• Assessed sequential addition of 15NH4Cl and 13C-methanol at varying ratios.

Main Results:

• 15N/13C isotopes are not required during the initial growth phase but are essential at low concentrations before methanol induction.
• The optimized P4 protocol using 15NH4Cl, 13C-glucose, and 13C-methanol reduced isotope costs by one-third compared to standard methods.
• Using 13C-glycerol further decreased costs.

Conclusions:

• An economical isotopic labeling method for Ovine interferon-tau in Pichia pastoris has been established.
• Strategic, late-stage application of isotopes significantly reduces production costs.
• This optimized protocol offers a cost-effective alternative for isotopic labeling in biopharmaceutical production.