Recombinant Expression in E. coli

E. coli is the most widely used host system for recombinant protein expression. The expression level in E. coli is in general higher than that in mammalian cells. The turnaround time is also much shorter. Hence, it’s a cost-effective option for scale-up production. In addition, E. coli can be used to produce proteins that are difficult to be secreted in mammalian cells.​

Over the years, Bon Opus has developed a collection of proprietary reagents and innovative approaches. Our in-house protein experts will help you explore different options and work closely with you each step of the way.

Feature Package: TotumPro™ E.coli Protein Production ($1500 per 2mg)

  • Starting from gene synthesis to protein expression and purification

  • One-step purification with tag(His, SUMO, MBP, GST)

  • 2mg purified protein at 90% purity(SDS-PAGE)

  • 6-8 weeks delivery time

General Workflow

1. Gene synthesis

2. Cloning & Transformation

3. Expression test

4. Scale up & Purification

Steps Breakdown

Codon Optimization

Codon optimization is a critical step in gene synthesis to improve the expression level in host system. Bon Opus will optimize your sequence specifically for E. coli  expression.

Strains & Expression

The strain of E. coli  plays an important role in doubling times and expression conditions. Bon Opus carries a large collection of E. coli  strains, allowing us to screen for the most efficient expression host for complex projects.

Expression Vectors

Vectors (and promoters) also have an impact on expression level. Different vectors can be used to drive expression under different culture conditions. Commonly used vectors include pSumo, pBAD, pET system, pQE system, pGEX system, and pBV220.

Culture Conditions

To achieve optimized expression, culture media (CD/LB/XY1) and culture temperature (37/30/16°C) need to be carefully selected. The use of fermenters - over traditional shake flasks - can also improve the outcome. Fig. 1

Fusion Tags

Fusion tags are used in E. coli to improve protein production yields, solubility and folding, and to facilitate protein purification. Based on our experience, 60% of insoluble cases can be solved by introduction of fusion tags. Commonly used tags include SUMO, GST, and TRX. Table. 1

In Vitro Refolding

Formation of inclusion bodies is the major challenge to express bioactive proteins in E. coli. Our team has years of experience with refolding. Out of 210 inclusion body cases, Bon Opus team was able to solve 140 cases by tuning refolding conditions. Fig. 2

Other Approaches

 

This may include the co-expression of chaperone proteins, in addition to periplasmic expression.

Dr. Kong Chen

University of Pittsburgh

We received custom protein production services from Bon Opus and were very satisfied with their product quality, turnaround time, and the enthusiasm of their staff. The team worked closely with us throughout the entire project and were very efficiently communicative with us to deliver the final products. I will continue to use their service and highly recommend their products to my collaborators.