Expression systems

As no universal system enables the expression of each and every recombinant protein, GTP offers a large variety of expression systems to best suits your needs.

We have extensive experience in working with bacteria (E. coli, L. lactis), yeasts (P. pastoris, S. cerevisiae), insect cells, and mammalian cells.

We will assist you in choosing the most appropriate expression system according to the protein and final objective of your project. In order to maximize the chances of success and optimize your development time, we also propose to evaluate several systems in parallel.

Whether you choose to assess one or several systems concurrently, we will use our experience to custom design, small scale expression trials in order to define the conditions allowing optimal expression of your recombinant protein.

• Systems
  • E. coli. We use classical E. coli expression vectors and strains. For projects concerning the development of therapeutics, we have developed three royalty free optimised expression vectors.
  • L. lactis. GTP has developed a proprietary expression system including a collection of strains and expression vectors. This system presents significant advantages for the production of high-added-value proteins and peptides.
• Scale
  • From shake flask to 2L, 5L, 50L and 300 L fermentors (with batch, fed-batch, chemostat strategies)

• Systems
  • P. pastoris
  • S. cerevisiae
• Scale
  • From shake flask to 2L, 5L, 50L and 300 L fermentors (with batch, fed-batch, chemostat strategies)

• Cell lines: Sf9, High Five, S2
• Expression strategies:
  • Baculovirus transfection
  • Stable cell line
• Scale: from flask to 5L, 10L, 25L and 50L bioreactors

• Cell lines: CHO, HEK,...
• Expression strategies:
  • Transient transfection
  • Stable cell line
  • Retrovirus transduced cell lines
• Scale:
  • For adherent cell lines: T-flasks, roller bottles
  • For suspension cultures: up to 50L scale with batch, fed-batch or perfusion strategies