SupernateIN™ Protein Expression Service

Biologics International Corp (abbr. BIC) provides supernatant protein optimization services are based on E. coli expression system, aiming to purify soluble proteins from the supernatant and reduce the protein expression of inclusion body. Our advanced SupernateIN™ technology platform can be applied to optimize the combination of different expression conditions. The optimization options include 9 host bacteria, 6 molecular chaperones, 9 soluble tags, dozens of vectors and multi-gradient temperature tests. On this platform, we have tested various inclusion proteins which should be refolded and 90% of them can regain high soluble protein expression level after our optimization. Soluble recombinant proteins expressed by SupernateIN™ are closer to the natural structure, which can be applied to the development of protein drug, antigen preparation, genetic engineering for antibody production, and screen recombinant vaccine.

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.

SupernateINTM Service Description

Soluble Protein Service Overview
Content Price Timeline Deliverables
Codon optimization adjust the codon usage frequency for soluble protein expression in E.coli expression system Please Inquire Customized according to your project
  • Soluble protein (Option)
  • Experimental reports
  • Codon optimization report
  • Vector optimization report
  • Expression condition optimization report
  • Protein solubility evaluation
  • Expression condition optimization generate an expression matrix and test significant factors that may contribute to high level protein solubility
    Sonication and centrifugation obtain optimized supernatant and run dot blot analysis to sort best candidates with highest soluble expression level
    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)

    Contact Us

    phone+1 (317) 703-0614
    fax +1 (855) 427-1516
     For questions and/or a price quote, please inquire online or fill in a pre-order form.