Carolyn Bertozzi, Doctoral Dissertation Advisor (AC)
- Cover Image, Volume 115, Number 1, January 2018. Biotechnology and bioengineering 2018; 115 (1): i
Development of a general defined medium for Pichia pastoris
BIOTECHNOLOGY AND BIOENGINEERING
2018; 115 (1): 103–13
Pichia pastoris is widely used as a host for recombinant protein production. More than 500 proteins have been expressed in the organism at a variety of cultivation scales, from small shake flasks to large bioreactors. Large-scale fermentation strategies typically employ chemically defined growth medium because of its greater batch-to-batch consistency and in many cases, lower costs compared to complex medium. For biopharmaceuticals, defined growth medium may also simplify downstream purification and regulatory documentation. Standard formulations of defined media for P. pastoris are minimal ones that lack the metabolic intermediates provided by complex components such as peptone and yeast extract. As a result, growth rates and per-cell productivities are significantly lower than in complex medium. We have designed a rich defined medium (RDM) for Pichia pastoris by systematically evaluating nutrients of increasing complexity and identifying those that are most critical for growth. We have also employed transcriptomics to gain deeper insights into the underlying metabolic processes and inform our media design. We have demonstrated that using RDM for expression of three heterologous proteins yields titers comparable to, or higher than, those in standard complex medium. RDM improves productivity of P. pastoris fermentations and its development demonstrates the usefulness of transcriptomics to accelerate process development for new molecules.
View details for DOI 10.1002/bit.26440
View details for Web of Science ID 000416114400009
View details for PubMedID 28865117
Reexamining opportunities for therapeutic protein production in eukaryotic microorganisms
BIOTECHNOLOGY AND BIOENGINEERING
2017; 114 (11): 2432–44
Antibodies are an important class of therapeutics and are predominantly produced in Chinese Hamster Ovary (CHO) cell lines. While this manufacturing platform is sufficiently productive to supply patient populations of currently approved therapies, it is unclear whether or not the current CHO platform can address two significant areas of need: affordable access to biologics for patients around the globe and production of unprecedented quantities needed for very large populations of patients. Novel approaches to recombinant protein production for therapeutic biologic products may be needed, and might be enabled by non-mammalian expression systems and recent advances in bioengineering. Eukaryotic microorganisms such as fungi, microalgae, and protozoa offer the potential to produce high-quality antibodies in large quantities. In this review, we lay out the current understanding of a wide range of species and evaluate based on theoretical considerations which are best poised to deliver a step change in cost of manufacturing and volumetric productivity within the next decade.Related article: http://onlinelibrary.wiley.com/doi/10.1002/bit.26383/full.
View details for DOI 10.1002/bit.26378
View details for Web of Science ID 000411699200002
View details for PubMedID 28688187