Our high throughput protein expression test service is the solution to overcome the most demanding challenges regarding difficult-to-express proteins! ProteoGenix developed a HTP platform dedicated to protein expression optimization. Our solution: 1000+ expression conditions carefully selected and tested in parallel to skyrocket your protein production in a short timeline.

High throughput protein expression test
for difficult-to-express proteins

ProteoGenix combines the knowledge of its best protein production experts to provide you the most advanced high throughput protein expression platform. Our high throughput platform was designed following one rule: “The more relevant conditions we test, the more probability we have to find the way to express your protein successfully”. Thus, our high throughput protein expression platform allows us to test 1000 conditions in 4 weeks in order to meet or even outperform your requirements in terms of:

  • Productivity
  • Purity
  • Solubility
  • Stability
  • Biological activity

Achieving such results is only possible by proposing a wide range of protein expression conditions. Here is a list of parameters ProteoGenix can vary:

Molecular Biology Capabilities

Gene synthesis




Signal peptide


Purification tag


Solubility tag


Strains And Cell Lines

Culture Conditions









Are you facing difficulties in protein expression optimization? Contact our PhD account managers to unlock the potential of your production.

Our high throughput
protein expression workflow

Determination of best host/vector pair

  • Test of several transformants
  • Selection of those presenting the best results
  • Purification tests on the best host/vector pair

Optimization of protein expression in flask

  • Optimization of several cultural conditions(temprature , induction time..)
  • Determination of the best feeding strategy

Optimization of protein purification


Optimization of protein expression in flask

  • Optimization of fermentor/bioreactor
    operating parameters
  • Protein purification of QC analysis: SDS/page,western

Example Of a Typical Project


  • 4 E. coli strains
  • 4 mammalian cell lines
  • 2 purification tags
  • 2 gene synthesis
  • 4 vectors
  • 5 signal peptides

2 Best System Contructions Combinations

1350 TESTS

  • 3 temperatures
  • 9 induction conditions
  • 5 purification optimization
  • 5 extraction methods

Best Expression Condition Selection

200 media screening

5 best fermentation conditions

1875 TESTS

Step Content Timeline Deliverables
Host/vector pair determination
  • Gene synthesis including codon optimization
  • Subcloning in expression vectors
  • Purification of the best results
  • To be determined depending on the project
  • Gene constructs
  • Detailed report including the tests performed
  • Purified protein from purification test
Protein expression optimization
  • Culture condition optimization
  • To be determined depending on the project
  • Test sample if required Detailed report
Protein purification optimization
  • Determination of best purification strategy
  • To be determined depending on the project
  • Purified protein Detailed report
Process development
  • Optimization of bioreactor operating parameters QC analysis
  • To be determined depending on the project
  • Purified protein Detailed report
  • Tag elimination via enzymatic cleavage
  • Endotoxin assay and removal
  • Scale up production / Fermentation

Influence of several parameters on protein expression

Production of difficult-to-express proteins requires varying several parameters that can strongly influence the final yield, purity, stability, solubility and biological activity. If we take a closer look at the productivity more specifically, here are some of the parameters to consider for protein expression optimization:

Expression System

The choice of the best expression system is of primary importance when it comes to protein expression. This choice will depend on your requirements: high productivity, proper protein folding, “human-like” post-translational modifications or a compromise between all of these requirements… Here is a small table explaining the essential parameters to consider when choosing the right expression system:

Gene Sequence

Gene synthesis should be optimized for the host organism by the so-called codon optimization process. This optimization aims at avoiding rare codons in the mRNA sequence thus limiting the risk of protein expression failing and increasing the chance to get a high yield protein production.


Protein expression optimization is also partly driven by the choice of the best expression vector. The non-coding sequence part regulates several elements essential to protein expression:

  • The promoter has to be adapted to the nature of the protein to express. For toxic proteins, promoters with low basal expression will be preferred. Strong promoters are privileged when high yield protein expression are required.
  • The terminator regulates the mRNA turnover and increases mRNA stability in the cytoplasm.
  • The origin of replication controls the plasmid copy number. Choosing a high copy plasmid can be an option if you face low yield protein expression.

Expression Conditions

Several factors are known to influence protein expression:

  • Temperature: in prokaryotic expression systems such as E. coli, protein expression results in incomplete protein folding and in the formation of inclusion bodies. Even if those inclusion bodies can be exploited, inducing protein expression at lower temperature allows for higher solubility.
    Hypothermic protein expression in mammalian cells results in higher protein expression yields.
  • Concentration of inducer: lowering the concentration of inducer leads to reduced transcription rate thus limiting the formation of aggregates (inclusion bodies) and increasing protein solubility..
  • Media: the growth media should contain all the necessary nutrients to favor recombinant protein expression.


This list is non-exhaustive and represents only part of the parameters ProteoGenix can optimize thanks to its high throughput protein expression service. Contact us to talk about your specific requirements with our PhD account manager who will define with you the best parameters to vary to optimize your protein expression.