Guaranteed Bacterial Protein Expression Services

NovoBacTM E.coli Expression, One-stop Solution with Guaranteed Success

*Free gene synthesis, free subcloning, FREE-If-Fail guarantee

Customer Provides Tag Options Amount* Timeline Purity Deliverables Pricing

Target protein sequence

With Tag
1mg - 3mg 3-5 weeks


  • Expression Plasmid
  • Expression Cell Line
  • Recombinant Protein
  • Data and QC reports
3mg - 5mg 3-6 weeks $1,399
5mg - 10mg 4-7 weeks $1,599
1mg - 3mg 6-8 weeks $1,499

*Protein amount is flexible according to the customer’s request.


  • Protein analysis and project proposal is utmost welcome and totally free.
  • To increase the expression level of your protein, codon optimization using our proprietary, ExpOptimizer™ technology, is recommended to be performed during gene synthesis.
  • Insoluble proteins maybe subject to protein refolding procedures.
  • In all cases, final protein will be guaranteed to meet listed specifications, failing which, any charge to the customer will be waived (exclusions are applicable to membrane proteins, toxic proteins and for target proteins greater than 100kDa).


NovoPro offers various recombinant protein & rAb expression platforms for any custom requirements. As our name, we aim to accelerate protein research by being a reliable partner and explore Novo-frontiers in science.

All the package services we are providing, are a customized, one-stop and 100% guaranteed solution:
*Free protein analysis and project design
*Free gene synthesis, free subcloning
*100% guarantee the amount and purity, no cost if the project fails
*Flexible with any customer’s requirements

Protein Expression System Recommended Species Recommended Quantity Post-translational Modification Protein Folding Purity Lead Time
E.coli All Species 1-20 mg None Partial ≥80% 4-8 Weeks
Insect/Baculovirus Expression System Eukaryotes 500 µg-5 mg Authentic All ≥90% 8-12 Weeks
HEK293, CHO Cells
(transient expression)
100 µg-5 mg Authentic All ≥85% 4-6 Weeks
HEK293, CHO Cells
(stable expression)
5 mg-5000 mg Authentic All ≥90% 8-10 Weeks

Proprietary codon optimization tool and professional construct design

The NovoPro’s codon optimization tool - ExpOptimizer is developed for the high expression of any target proteins in any mainstream expression hosts. Its comprehensive codon optimization algorithm considerate dozens of key factors of gene transcription and translation. You may optimize sequence at: Here

To maximize the chance of success, NovoPro protein expert will design a construct based on the characteristics and specific requirements of the target protein. For examples:


  1. Carrying cspA low-tep promoter, 11℃ induction, increasing the protein solubility;
  2. SD sequence inside, increase initiation codon efficiency;
  3. Forming TEE sequence, enhance the DNA transcription, thus boost the protein expression;
  4. AMP resistance screening.


  1. Carrying cspA low-tep promoter, 11℃ induction, increasing the protein solubility;
  2. With SUMO fusion protein, forming 3-D structure, promoting protein folding accuracy.
  3. SUMO enzyme precisely slicing fusion protein, no residues in N-terminal;
  4. Kan resistance screening.

E.Coli expression, ArcticExpress System and Advanced plasmid for Guaranteed Quality

Production procedures

protein expression timeline

ArcticExpress 11℃ Expression, Overcoming Protein Misfolding and Insolubility

Low Growth Temperatures Significantly Enhance Protein Folding and Solubility

Figure 1. X-21p expression at both 11°C and 30°C. Solubility of X-21p was enhanced at the lower growth temperature in all cells expressing chaperonin Cpn60 and co-chaperonin Cpn10.

Improved Protein Activity with Cold-Adapted Expression Technology

Figure 2. ArcticExpress Cells (11°C) and BL21-Gold Competent Cells (37°C) were used to express phosphatase proteins PTEN and MTMR7 with GST epitope tags. Phosphatase activity was enhanced in proteins expressed in ArcticExpress system at 11°C.

Frequently Asked Questions(FAQs)

1. Why shall I choose NovoPro to produce custom protein expression?

NovoPro provides unparalleled protein services with the following features:

(a) Your custom requests are handled by experienced scientists – we have successfully delivered >3,500 custom proteins. (b) High success rate – our E. coli protein expression system has 92% success rate; the success rates of the other expression systems are also much higher than the industry's average. (c) High capacity – up to 100L bacterial protein production, 100L mammalian protein production. (d) NovoPro is the only company has the Success Guaranteed or Totally Free policy for protein expression and protein crystallization (bacterial system) in the whole industry worldwide. (e) NovoPro developed sophisticated operational platforms with advanced technologies to solve your protein puzzles.

2. What is "Crystallographic grade" protein?

The protein for crystallization should be homogeneous and have >90% purity. The purity of protein shall be checked by HPLC or MS before crystallization. DLS (dynamic light scattering) result is helpful but not required. The minimum amount is 10mg/ml * 300ul. NovoPro can also provide a success guaranteed Crystallography services. Please visit:

3. How much experience does NovoPro have for custom protein services?

We started providing custom protein service since 2014. Till the end of 2018, more than 3,500 batches of custom proteins were successfully produced and delivered.

4. How many protein expression systems does NovoPro offer?

NovoPro provides custom protein services in E. coli and mammalian expression systems.

5. How can I choose an expression system for my protein?

It depends on the source (e.g. bacteria or animal) of your protein and the application of the purified protein. If post-translational modification is not required for the protein, E. coli protein expression system is recommended for its low cost and high success rate; otherwise mammalian cell expression system will be recommended based on your budget and specific requirements. Please quote with our PhD level customer service representative to find out a proper expression system for your target protein.

6. What are the capacities of NovoPro’s protein expression platforms?

For Bacteria (a) Provides large quantities of protein, up to grams; (b) Provides homogeneous recombinant proteins, over 98% purity.

For Mammalian Cell System: (a) Provides homogeneous recombinant proteins, over 98% purity; (b) Provides large-scale protein production, up to hundreds of milligrams (or 100 liter culture); (c) Provides stable cell lines.

7. What starting materials do I have to provide?

All we need to start with is the sequence information of your target protein/gene. We can start with gene synthesis with codon optimized for protein expression, and deliver you the final protein product. But if you would like us to start with your plasmid/virus, you are welcome to send them to us.

8. Does codon optimization really matter?

Codon optimization can greatly increase the level of protein expression. NovoPro ExpOptimizer™ is the most powerful codon optimization technology. Thousands of cases have proven the effectiveness of codon optimization at NovoPro.

9. How much protein can your team usually obtain from 1L pilot project in different expression systems?

Proteins differ in their protein expression levels in each expression system. Here are the averaged protein expression levels in the four expression systems:

(a) In bacteria system, the average is 1-5 mg/L. Our highest record is 200 mg/L.

(b) In mammalian system, the average is 1-5mg/L (regular recombinant proteins) and 10-20mg/L (antibody). Our highest record (for antibody) is 300 mg/Liter.

10. Why NovoPro recommend 1L pilot scale protein expression before scale up?

By optimizing the expression conditions in 1 liter pilot scale protein production, we can accurately estimate the amount of culture and purification requirement for your custom protein so that it may save your time and budget.

11. Does protein's Molecular Weight (MW) matter for protein production?

NovoPro protein services can express proteins of MW 10-250 kD (E. coli system: 150 kD; other systems: 250 kD). It becomes more and more difficult to produce proteins with bigger sizes, which tend to degrade and are hard to express.

12. Why do we ask whether the native form of the protein is a membrane protein, cytosolic protein, enzyme or protease or IgG Ab?

Unlike cytosolic proteins, most membrane-associated proteins are difficult to express and are usually insoluble in common buffer. Therefore, membrane proteins are exclusive from the Guaranteed Package. For enzyme/protease, we need to keep their activity. Usually the purification is performed at low temperature, and some protect reagent will be added.

13. For antibody generation, are there special requirements for the production of antigen protein?

The antigen (protein) should be soluble in a PBS or a buffer without organic solvents. Small tags (such as 6xHis, HA, FLAG, V5, c-myc) are preferred, GST is usually ok for protein antigens.

For mAb reagent development, protein antigen shall be >2mg and >50% purity (for diagnostic or functional mAb development, higher purity is preferred, 85-90%); for pAb reagent development, protein antigen shall be >3mg and >85% purity (additional 5mg is needed for purified pAb development).

14. What is the concentration of protein you usually gets from E coli expression system?

We usually got 0.1 - 3 mg/ml concentration (we can guarantee > 0.1mg/ml). We can concentrate the protein upon customers' special request (without additional fee for most cases). But highly concentrated protein tends to precipitate.

15. What if the protein can't be expressed and purified in E. coli system?

There are a few things NovoPro scientists will do to solve the problem: (1) Codon optimization is recommended if it has not been; (2) remove the transmembrane region and signal peptide region; (3) try to express truncated domains of the protein; (4) we can also try different tags to increase the expression level; (5) we may recommend customer to try different expression systems (e.g. mammalian cell system for certain proteins).

16. Does NovoPro refold protein produced in mammalian system?

In most cases, we do not perform refolding with protein produced in mammalian systems. In other words, proteins expressed in mammalian systems is usually soluble.

17. I want to express a heterodimer constitutes with two subunits. How would you suggest, in one construct or in two constructs?

The exact experimental strategy should be treated case by case, but both are fine with certain proteins. NovoPro has success records in both cases.

18. In E. coli protein expression system, will you purify the protein from the soluble fraction or insoluble fraction of the cell lysate? Can you refold insoluble protein?

We can purify the protein from both fractions. It will depend on client's requirement or available protocol. Our scientists have very good experience in protein refolding. Selection of particular refolding strategy is based on proteins' sequences and their structural properties. Usually, the refolding service is free of charge.

19. What purification methods does NovoPro have in house?

NovoPro can perform affinity purification, ion exchange chromatography, hydrophobic chromatography and size exclusion chromatography.

20. Can NovoPro perform antibody affinity purification?

If customer provides the protocol, we can do that.

21. What tags does NovoPro recommend for protein expression and purification?

The common tags to use are GST, MBP. Trx, TF, MBP, Nus, SUMO, Flag, Fc, and so on. NovoPro scientists may recommend different tags for different proteins based on the protein's property and the customer's specific requirements. His tag, either alone or fused with other tags (e.g. His-GST, etc.), is the most common one used for purification.

22. Can NovoPro remove the tag after purification? If so, how much it will cost and how long it will take?

NovoPro can remove the tag after purification, in case of that the tag is added with TEV or protease cleavage site. For cost and timeline, please quote with our customer service representatives.

23. What protease cleavage site does NovoPro recommend to introduce between the tag and the target protein?

For tag removal purposes, NovoPro recommends Enterokinase, Thrombin, TEV protease, 3C protease (Precision Protease) or SUMO protease cleavage site between the tag and target protein.

24. Where shall we introduce the tag and the protease cleavage site (C- or N-terminal)?

We recommend introducing the protease cleave site and the tag at the N-terminal. We do NOT recommend introducing protease cleavage site at the C-terminal, because it will leave extra 4-6 amino acids after protease cleavage of the C-terminal tag.

25. After N-terminal tag removal for the recombinant protein, what cleavage site will not leave any residue?

N-terminal EK site and SUMO will not leave any residue. N-terminal TEV protease cleavage will leave one extra amino acid "G"; 3C protease (Precision protease) cleavage will leave two amino acids "G" and "P".

26. How to determine the protein purity and quantity?

Methods for purity determination: (a) SDS-PAGE determination; (b) HPLC determination;

Methods for protein concentration determination: (a) Branford protein assay; (b) BCA protein assay; (c) Intensity measurement on the SDS-PAGE gel with a BSA standard curve.

27. Do you regularly check endotoxin level for custom proteins?

We do not regularly test endotoxin level of the produced proteins. Upon customers' requests, we can detect and remove endotoxin in the protein product at additional fees.

28. What QC data do you provide for protein expression?

NovoPro provides free SDS-PAGE and free Western blot using anti-His or anti-GST for tagged protein as QC. Customers can order additional QC results with HPLC, MS-ID, LC-MS/MS coverage and N-Terminal Sequencing at additional fees.

Protein Shipping & Storage

29. I may want to order large scale protein production later, but not now. How long will NovoPro keep the expression vector for me?

After an order is delivered, NovoPro will keep the bacterial strain for protein production for 3 months, and the expression vectors related to E. coli, mammalian expression systems for >2 years. There is no additional fee for this service. However, if client did not request to preserve the plasmid for him/her, we may destroy the product without any obligation.

30. What is your default buffer for protein delivery?

Tris-HCl, PH 8.0, containing NaCl 150 mM. To use the following reagents, we will communicate with the client: 5 mM DTT, 0.3% SKL, and 1% SDS.

31. Does NovoPro ship the produced protein in lyophilized or liquid form?

We ship in liquid form.

32. Usually, under what condition does NovoPro recommend for protein storage?

Please aliquot the protein into separate vials and store at -80°C or liquid nitrogen for long-term storage. Avoid multiple frozen and thaws.