Cusabio Research Recombinants


For more than 14 years, the CUSABIO Protein Expression Platform has established five Research recombinant expression systems from prokaryotes (E.coli) to eukaryotes (insect baculovirus, mammalian cells and yeast), and has also created a protein expression system Unique in vitro E.coli, which allows expressing transmembrane proteins that are normally quite difficult to express. In addition, the CUSABIO protein quality control department owns a professional technical team, equipped with advanced experimental apparatus, to ensure that each protein has a complete and high-quality COA report. CUSABIO purified proteins exceed 90% purity as detected by SDS-PAGE analysis.

We currently have 67 native proteins, 100 small molecule antigens, 640 active proteins, more than 4,400 recombinant proteins in stock, more than 8,900 recombinant proteins developed, more than 13,000 cDNA clones, more than 36,000 transmembrane proteins, more than 500,000 semi-custom recombinant proteins and we could also provide risk-free protein expression service and gene and oligo synthesis service. All these products belong to our Line of Protein Products.

Why choose us?

1. 100% risk-free performance guaranteed

CUSABIO protein products are carefully validated under strict quality control standards to ensure performance. If the product doesn’t work as promised in the manual, just contact us before the expiration date for technical support, replacement or refund.

2. Strict quality control process

The quality of our proteins is the cornerstone of our ability to serve our customers. For this reason, we invest enormous resources in the development of proteins, validating their application, managing, controlling and improving quality. Each protein will go through our standardized quality control process before shipping.

  • Protein concentration detection
  • molecular detection
  • purity detection
  • Endotoxin detection
  • Detection of biological activity (This procedure only applies to proteins with validated activity)
  • Sequence Accuracy

3. Customer Testimonials

I hope this email finds you well. I recently ordered 50ug of Human Protein Carbonic anhydrase 9 (CA9) and I am very pleased with it. We have ordered this protein 5 times in total and all batches perform well. Now we would like to order 10mg and we think the new lot will also do well in our detection.

4. Characteristics of the five expression systems

We have five recombinant expression systems, including yeast, E. coli, baculovirus-infected insect cell, mammalian cell, and cell-free (E. coli in vitro). Different expression systems have various characteristics and are suitable for expressing different proteins, which can satisfy different experimental requirements of researchers. Here is an introduction to the characteristics of five expression systems that might help you choose a suitable system.

5. Multiple Labels for Recombinant Protein

We could provide multiple labels for each protein to meet the different needs of different customers. Here we list the possible tag types for each expression system.

6. Bulk order

  • Capacity

Large fermentation tanks (50L, 500L) allow us to produce proteins on a large scale. We have successfully completed industrial bulk orders for 100mg, 200mg and 500mg.

  • Order application

You can use the protein name/catalogue number/alias/abbreviations/Uniprot number to search for your desired protein in the above search bar, which contains millions of proteins, then you can request the quotation via live chat or send your request to protein1@cusabio. com. If you can’t search for the protein of your interest, please fill in the “Custom Protein Request Form” online, your information will be strictly protected and will not be disclosed to third parties, we will reply to you by email within 24 hours.

7. Professional R&D team

Our company has an R&D team made up of scientists with doctoral and master’s degrees. More than 60% of the total number of employees are in the technical service team, including 20% ​​with PhD degrees and 40% with Master’s degrees; The technical elites are from recognized national institutions, with years of experience in protein development.

8. Animal free

CUSABIO is pleased to inform you that we have developed our line of animal-free recombinant proteins, which drastically minimize variable factors and the possible contamination of mammalian pathogens during the production process. These animal-free proteins are produced in animal-free media, and the purification kit is also free of animal components. Animal-free recombinant protein is worth owning!

9. Good Manufacturing Practice (GMP) Grade Proteins

  • 4000㎡ research laboratories
  • 2000㎡ GMP level production workshop

10. The number of new products

Our protein expression platform has established five prokaryotic to eukaryotic recombinant expression systems and has also built a cell-free expression system. We also established a special and independent protein quality control department, which meets the quality standard of the international protein market, to detect purity, activity, endotoxin level, etc. of the proteins. With our professional R&D team, we can develop and produce more than 2700 proteins every year.

11. Multiple delivery forms

  • Liquid form

The default delivery form is liquid form. If the customer has demand for freeze-dried form, please note this requirement when placing the order.

  • Lyophilized powder

Relatively speaking, the lyophilized form will be more stable than the liquid form and the shelf life will be longer. But freeze-drying can damage the protein structure and can affect the activity of some proteins.

Additional services

1. Label removal service

  • If you need to remove the tag, please contact us in advance; otherwise, we will not remove the tag.
  • Not all protein tags can be removed, as some proteins will be highly unstable after tag removal.
  • If we manage to remove the label, we will charge an additional cost.
  • If we are unable to remove the label, we will not charge any additional costs.
  • Generally, the delivery time will be extended by 2-3 days.

2. Western Transfer Service

  • We could offer Western Blot service to label antibodies for free. If the customer has a demand, please provide this information when placing the order.
  • Generally, the delivery time will be extended by 2-3 days.
  • The WB detection result will be displayed in COA.