Protein Expression Services
Protein production using recombinant technologies continues to revolutionize all aspects of life and life sciences. Essentially, a gene encoding a protein of interest is expressed to make the protein at dramatically enhanced yield and or with greatly improved characteristics in the native organism or in heterologous hosts. Recombinant production of proteins involves transforming cells with a desired gene in a DNA vector. The gene then translates into its corresponding protein. The expressed protein can then be extracted by lysing the cells and subsequent purification steps. In some cases, the protein made in the cells is exported into the culture medium through protein secretion machineries.
Bacterial, yeast, insect and mammalian expression systems are widely used. Each system has its own advantages and disadvantages. Selection of a particular expression system for a given protein should be based on many factors, such as the type, origin and function of the protein, technical challenges, applications, and regulatory considerations. Bio-Technical Resources offers several microbial expression systems, typically much more productive and affordable than insect and mammalian systems.
A brief introduction to these expression systems is provided in a downloadable PowerPoint presentation BTR multiple host systems for protein expression (pdf). In addition to these platform organisms, BTR has experience working with numerous other microorganisms such as Lactobacillus lactis, Bacillus licheniformis, Hansenula polymorpha, and Myceliophthora thermophile C1 (previously known as Chrysosporium lucknowense C1).
BTR was previously a North American representative for two proprietary protein expression systems, Hansenula polymorpha (property of ARTES Biotechnology GmbH) and Bacillus licheniformis (property of Koninklijke DSM N.V ), but no longer represents these proprietary systems. BTR will work with our clients’ specific microbial strains producing products that are categorized as BSL1.
No single host system is the best option for all types of proteins and applications. BTR has the capacity and proven experience to help you to choose and develop the most efficient production system for your protein of interest (POI).
Five non-proprietary protein expression systems are available at BTR. Please visit the respective webpages linked to the individual buttons below:
- E. coli: intracellular and secreted (periplasmic) protein
- Bacillus subtilis: intracellular, and secreted protein in particular
- Saccharomyces cerevisiae: mainly intracellular protein
- Pichia pastoris: intracellular, and secreted protein in particular
- Trichoderma reesei: secreted protein
The microbial expression hosts offered by BTR have the potential to produce your intracellular or secreted protein of interest. Each system has strengths and weaknesses.
BTR will help you select one microbial host, via a phased Development Program, to serve as a protein expression platform to meet your present and future needs:
- Phase 1: focus on a feasibility study, using one or more host systems. This study will evaluate generated strains in shake flask culture.
- Phase 2: construct and evaluate advanced strains to improve protein expression. The "best" of the candidate production strains will be selected from shake flask and 1-L fermentor cultures.
- Phase 3: optimize a fermentation process, and scale-up and demonstrate the process at BTR`s 14-L and 60-L or 250-L pilot scales. A Technology Transfer Package will be prepared that supports transfer of the strain to a commercial fermentation facility.
Several projects of R&D services in this area are highlighted in PowerPoint slideshow Protein expression examples (pdf).