SupernateIN™ Protein Expression Service

BiologicsCorp owns a self contained and complete optimization platform for supernatant protein expression which contains 9 host bacteria, 6 molecular chaperones, 9 soluble tags, dozens of vectors, as well as multiple temperatures and induction strategies. Combining the techniques, we have tested many soluble proteins that are normally expressed in inclusion bodies. More than 90% of them have resulted in at least one optimal condition under which high level of target protein expression is achieved in soluble fraction.

SupernateINTM Service description

Content A complete set optimization for your protein of interest
Deliverable Soluble protein (Option)
Experimental reports

  • Codon optimization report
  • Vector optimization report
  • Expression condition optimization report
  • Protein solubility evaluation
Timeline Customized according to your project
Price Please inquire
Additional services Basic guaranteed package, Fermentation, Tag-free,
Endotoxin control, High-throughput protein production

SupernateINTM Service process

Soluble Protein Service Overview
  1. Codon optimization: adjust the codon usage frequency for soluble protein expression in E.coli expression system
  2. Expression condition optimization: generate an expression matrix and test significant factors that may contribute to high level protein solubility
  3. Sonication and centrifugation: obtain optimized supernatant and run dot blot analysis to sort best candidates with highest soluble expression level
  4. Scale up production: produce soluble protein with guaranteed quantity and purity

Soluble expression optimization technology strategies

Strategy Principle Content
Codon optimization produce pauses to slow down translation rate and balance the essential factors of soluble protein expression Our in-house MaximaTM codon optimization program is developed to solve the problems for soluble protein expression.
Strains Choose the best fit strain based on your protein of interest to improve soluble expression level of native folding protein
  • Arctic Express strain: contribute to soluble protein processing at low temperatures
  • BL21 Star (DE3) strain: increase mRNA stability by attenuation of RNases activity
  • Rosetta and BL21 Codon Plus strains: supply extra copies of rare tRNAs
  • Origami and new SHuffle strains: facilitate disulfide bond formation and protein folding in the E.coli cytoplasm
  • C41 (DE3) and C43 (DE3): accelerate synthesis of membrane proteins
Vectors Choose the best fit vector based on your protein of interest to improve soluble expression level of native folding protein
  • pET vector
  • pCold vector
  • In-house fusion vector
Expression temperature Slow down the rate of protein synthesis and folding kinetics, decreasing the hydrophobic interactions that are involved in soluble protein self-aggregation Cold-inducible promoters are used to maximize protein expression under low temperature.
Inducer concentration Reduction in cellular protein concentration High inducer concentration is potentially toxic to E.coli and accelerate formation of inclusion bodies
Growth medium Improve growth medium nutrient
  • Control pH fluctuation in the medium during growth.
  • Add 1% glucose to repress induction of the lac promoter by lactose.
  • Add polyols and sucrose to leads to the accumulation of osmoprotectants in the cell, which stabilize the native protein structure.
  • Add low MW thiols and disulfides, or NaCl
Fusion protein Work as solubility enhancing partners More than 70% of the proteins tested showed high expression of soluble protein with at least two of nine fusion partners
Available fusion tags: GST, MBP, NusA, IF2, barnase, Pfg27-17, intein, Trx and CaBP.
Co-expression Assist initial folding in soluble protein expression Molecular chaperones promote the proper isomerization and cellular targeting by transiently interacting with folding intermediates.

  • GroES-GroEL
  • DnaK-DnaJ-GrpE
  • ClpB

Foldases accelerate rate-limiting steps along the folding pathway.

  • Peptidylprolylcis/trans isomerases (PPI’s)
  • Disulfide oxidoreductase (DsbA) and disulfide isomerase (DsbC)
  • Protein disulfide isomerase (PDI)

Case study

SupernateINTM soluble protein expression for a scFv

SDS-PAGE for Supernatant scFV expression

After optimization, the soluble protein was expressed in supernatant.

Chart for Supernatant scFV expression

After optimization, the soluble protein expression level in supernatant was significantly improved.

Contact Us

  +1 (317) 703-0614
  +1 (855) 427-1516