Microbial cell line development

GTP has extensive experience developing microbial strains for the manufacturing of biologics.

Our microbial cell line development services aim to develop high producing clones. We include adapted  product quality analysis into our selection process to ensure that not only productivity but also critical product attributes targets are met.

E. coli

Diversity of GMP compliant microbial hosts for the manufacturing of biotherapeutics

Our team has extensive experience using a diversity of E. coli established systems for the production of challenging proteins. We offer optimised IP-free vectors that are designed for improved protein expression and stability and have successfully developed processes with a diversity of expression strategies: cytoplasmic, periplasmic, soluble and insoluble (inclusion bodies).
For secreted proteins, we will most often opt for expression in P. pastoris (now renamed Komagataella phaffii) which is an established, FDA approved and highly competitive expression host. Our team has successfully produced a diversity of proteins (enzymes, cytokines, antibody-derived fragments…) using the methanol-inducible AOX promoter or the constitutive GAP promoter.

L. lactis

E. coli strain development services

Our approach consists in screening a complete set of parameters in order to select the optimal strain and expression conditions:

  • Identification of the optimal strain and expression strategy:
  • Screening of several optimised gene sequences
  • Screening of promoters
  • Screening of expression strains
  • Screening of expression strategies: soluble/insoluble, periplasmic/cytoplasmic, co-expression with chaperones
  • Evaluation of plasmid stabilisation sequences
  • Optimisation of expression conditions: induction, media, temperature and kinetic
  • Generation and characterisation of research cell bank
Pichia pastoris

P. pastoris strain development services

The key when developing a P. pastoris manufacturing strain is the capacity to screen a large number of clones to select the hyper producing ones. To that purpose, GTP has developed a high-throughput microscale cultivation process.

A classical P. pastoris strain development project includes the following steps:

  • Identification of the optimal strain and construct:
  • Screening of strains
  • Screening of promoters
  • Screening of signal sequences   
  • Extended screening of up to several thousand clones to identify high-producer clones
  • Optimisation of expression conditions: kinetic, pH
  • Generation and characterisation of research cell bank
GTP also offers microbial upstream process development