Application of simple fed-batch technique to high-level secretory production of insulin precursor using Pichia pastoris with subsequent purification and conversion to human insulin

authored by

Chandrasekhar Gurramkonda, Sulena Polez, Natasa Skoko, Ahmad Adnan, Thomas Gäbel, Dipti Chugh, Sathyamangalam Swaminathan, Navin Khanna, Sergio Tisminetzky, Ursula Rinas

Abstract

Background: The prevalence of diabetes is predicted to rise significantly in the coming decades. A recent analysis projects that by the year 2030 there will be ~366 million diabetics around the world, leading to an increased demand for inexpensive insulin to make this life-saving drug also affordable for resource poor countries.Results: A synthetic insulin precursor (IP)-encoding gene, codon-optimized for expression in P. pastoris, was cloned in frame with the Saccharomyces cerevisiae α-factor secretory signal and integrated into the genome of P. pastoris strain X-33. The strain was grown to high-cell density in a batch procedure using a defined medium with low salt and high glycerol concentrations. Following batch growth, production of IP was carried out at methanol concentrations of 2 g L^-1, which were kept constant throughout the remaining production phase. This robust feeding strategy led to the secretion of ~3 gram IP per liter of culture broth (corresponding to almost 4 gram IP per liter of cell-free culture supernatant). Using immobilized metal ion affinity chromatography (IMAC) as a novel approach for IP purification, 95% of the secreted product was recovered with a purity of 96% from the clarified culture supernatant. Finally, the purified IP was trypsin digested, transpeptidated, deprotected and further purified leading to ~1.5 g of 99% pure recombinant human insulin per liter of culture broth.Conclusions: A simple two-phase cultivation process composed of a glycerol batch and a constant methanol fed-batch phase recently developed for the intracellular production of the Hepatitis B surface antigen was adapted to secretory IP production. Compared to the highest previously reported value, this approach resulted in an ~2 fold enhancement of IP production using Pichia based expression systems, thus significantly increasing the efficiency of insulin manufacture.

Organisation(s)

Institute of Technical Chemistry

External Organisation(s)

Helmholtz Centre for Infection Research (HZI)
International Centre for Genetic Engineering and Biotechnology
Fraunhofer Institute for Toxicology and Experimental Medicine (ITEM)

Type

Article

Journal

Microbial cell factories

Volume

9

ISSN

1475-2859

Publication date

12.05.2010

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Biotechnology, Bioengineering, Applied Microbiology and Biotechnology

Sustainable Development Goals

SDG 3 - Good Health and Well-being

Electronic version(s)

https://doi.org/10.1186/1475-2859-9-31 (Access: Open)
http://hdl.handle.net/10033/139961 (Access: Open)