RayBiotech has provided Custom Protein Services since 2006. Our comprehensive service program covers every step of production from gene cloning through protein purification, and includes downstream processing such as protein desalting, lyophilization, vialing, and conjugation to tags, fluors, or other labels. If you can’t find your protein of interest on the market, please contact our technical support team to discuss your project and create a custom quote. Our expert team of scientists is here to help you achieve your research goals.
RayBiotech offers 2 different gene expression systems to serve a variety of research requirements. See chart below for a comparison of features and specifications.
|Characteristics||Bacteria||Mammalian Cells (TruExp™)|
|General Features||Expression Level||Low-Medium-High||Low-Medium-High|
|Cell Doubling Time||Rapid (30min)||Slow (24hr)|
|Time Line||3 Weeks||4-5 Weeks|
|Post-Translational Modifications||Protein Folding||Not Reliable||Very Reliable|
TruExp™ is a state-of-the-art mammalian cell-based expression system developed by RayBiotech which efficiently delivers recombinant proteins with native conformations and post-translational modifications (PTMs). A result of years of effort by the R&D team, TruExp is an ideal system for the production of mammalian proteins which must retain some or all of their native functions, and an excellent option for high molecular weight or difficult to express proteins.
Figure 1. Raybiotech TruExp Mammalian Cell Gene Expression System demonstrates gene over-expression and secretion. Six human genes (H1-6) and 3 mouse genes (M1-3) were expressed by the TruExp expression system. Cell culture supernatants (10 µL) were applied to 12% SDS-PAGE (A) and Western blot probed with anti-his tag monoclonal antibody (B). Except for genes H6 and M2, all overexpressed genes display additional secreted protein bands (A, red arrows). All genes were expressed, with some displaying abundant post-translational modifications, evident by increased molecular weights compared to the predicted sizes (B, yellow arrows). M = protein standard markers (kDa).
Figure 2. Representative purified human proteins from Raybiotech TruExp Mammalian Cell Gene Expression System.Affinity-purified recombinant proteins from culture supernatants of transfected mammalian cells exhibit high purity and intact protein bands, even at MW larger than 100 kDa. M = protein standard markers (kDa).
|Serpin B4, Serpin Peptidase Inhibitor||SCCA2||335.7|
|14-3-3 Protein Epsilon||YWHAE||103.1|
|N-terminal of the prohormone BNP||NT-proBNP||99.5|
|Brain natriuretic peptide 32||BNP-32||51.2|
|Receptor Tyrosine-Protein Kinase erb-3||erbB-3||37.5|
|Epidermal Growth Factor Receptor||EGFR||23.5|
|Pepsinogen II, Pepsinogen C||PGC||18.6|
|Lymphocyte Activation Gene 3 Protein||LAG-3||16.9|
|Receptor Tyrosine-Protein Kinase erbB-2||Erb/Her2||16.7|
|Hepatocyte Growth Factor Receptor||HGF R||14.6|
|Golgi Membrane Protein 1||GP73||5.5|
|Phase 1: Gene cloning||1 week||Use your expression vectors without any modification||N/A|
|Gene synthesis and codon optimization||Recombinant expression vector DNA, 2 µg|
|Subclone your gene into an expression vector||DNA sequencing chromatography data|
|Phase 2: Large-scale gene expression||1 week||Transform DNA sequence-confirmed recombinant plasmid into bacteria||Bacterial glycerol stocks transformed with recombinant expression vector, 2 vials, 0.5 mL/vial|
|Express protein in 2 liters of culture|
|Collect, lyse and extract the induced cells|
|Centrifuge to obtain the supernatant fractions for purification|
|Phase 3: Protein affinity purification||1 week||Protein affinity chromatography purification||Comprehensive report including induction conditions, method of extraction, SDS-PAGE data, protein concentration, etc.|
|Determine the protein purity by SDS-PAGE with Coomassie blue staining||Affinity purified proteins (95% purity guaranteed)|
|Protein desalting||Aliquoting, lyophilization and conjugation of purified proteins are available upon request|
|Determine the protein concentration|
|Concentrate the samples if protein concentration is low|
|Phase 1: Gene cloning||1.5 weeks||Use your expression vectors without any modification||N/A|
|Gene synthesis and codon optimization||DNA sequencing chormatography data. If you provided your own expression vectors, you will also receive: 1. Recombinant expression vector DNA (2 µg); 2. The glycerol stock transformed with plasmid (1mL)|
|Provide gene template or subclone your genes into either an expression vector provided by you or an overexpression vector from Raybiotech, Inc.|
|Phase 2: Gene Expression||1-3 weeks||Small scale of gene expression: transfect 2 ml of HEK293 suspension cell cultures using the sterile recombinant plasmid DNA||SDS-PAGE and Western blotting results|
|SDS-PAGE and Western blotting analysis to confirm the gene expression, expression levles, protein secretion, protein solubility, etc.|
|Upon request, perform large scale of gene transfection (100-500 ml)|
|Centrifuge to obtain the culture supernatant and cell pastes for purification|
|Phase 3: Protein affinity purification||1.5 weeks||Cell lysis, protein extraction, centrifugation, etc.||Comprehensive report including induction conditions, method of extraction, SDS-PAGE data, protein concentration, etc.|
|Protein affinity chromatography purification from lysate and/or cel culture supernatant, desatling, etc.||Affinity purified proteins (95% purity guaranteed)|
|Determine the protein purity by SDS-PAGE with Coomassie blue staining||Comprehensive report from gene cloning to protein expression and affinity-purified proteins (protein lyophilization, conjugation, vialling, etc. is up to the customer's request)|
|Determine the protein concentration. Concentrate the samples if protein concentration is too low|
|QC process, deliver protein product and project report, etc.|
To complement our Gene-to-Protein service packages, RayBiotech offers an array of molecular biology technical services for your convenience. These services can be purchased individually or included in your custom service contract. Our technical specialists are available to consult with you and plan a work flow that addresses your specific research goals.
Our molecular biology services include, but are not limited to: