Bacterial Expression System

The prokaryotic expression system generally takes E. coli as the host cell. Since the cell has advantages like rapid proliferation, high expression, easy purification, good stability, strong anti-pollution ability and low cost, prokaryotic protein expression system is not only the most mature and reliable, but also the most commonly used, the most economical and effective expression system in the experiment of protein expression at present.

However, there are some difficulties in the prokaryotic expression system. For example, current codon usage bias in CDS or carrier regulatory elements are incompatible with the host bacteria, which may leads to the failure of interest protein expression or low expression; or even though the expression of interest protein succeeds, it is not soluble.

With the help of industry-leading codon optimization software NGTM Codon and more than ten years’ experience in professional protein expression and purification, Synbio Tech. provides professional technical support for you in every link of the prokaryotic expression. We not only ensure the expression quantity of your protein, but also ensure the high purity of the delivery according to your needs so that you can focus on the follow-up experiments.

Service flow chart

  1. Project analysis
  2. Sequence optimization
  3. Recombinant plasmid construction
  4. Lab scale: Optimization of expression condition
  5. Expand culture induced expression and purification
  6. Post processing of purified protein


  1. Express vector construction(optional)

Express vector construction including codon optimization, gene synthesis and sub cloning.

With Synbio Tech.’s industry-leading codon optimization software NGTM Codon, the gene expression level can be increased by several times or tens of times after optimization. The genes synthesized by our excellent synthetic biology Syno® platform were embedded into the best expression vector and it was verified by sequencing that the sequence of inserted recombinant plasmids were 100% correct. Synbio Tech. can provide customers conventional prokaryotic expression vector, such as pET, pCOLD and other common commercial vector series. In addition, Synbio Tech. also utilized powerful synthetic biology element construction function to optimize and reconstruct the pSYNO series prokaryotic expression vectors for you to choose from, including sumo, MBP, GST, Trx and tags promoting solubility and expression level. Please contact for details.

Delivery form: 1 tube of lyophilized plasmid (4ug/tube), 1 tube of puncture strains; 1 copy of sequencing verification report

Delivery TAT: 10-20 business days (depending on the length and complexity of genes)

  1. Optimization: expression conditions

Under the premise of ensuring sequence correction, the influence of host bacteria on the expression effect is also very obvious. Synbio Tech. will transform recombinant plasmids with accurate sequences into the optimal expression host bacteria, including BL21 (DE3), Arctic Express (DE3), TOP10F, Rosetta (DE3) pLySs, Rosetta-gami B (DE3) and those strains with special skills. We will select at least 6 positive colonies to conduct expression laboratory scale test and optimization after transformation. During the test process, we will optimize the culture conditions which are suitable for various strains, including temperature, culture medium, inducer type, induction time, induction quantity and other factors. After the testing of expression quantity and solubility through SDS-PAGE, we offer feasibility suggestions about whether or not to enlarge and the enlarge scale.

Delivery contents: A report of laboratory scale test verification

Delivery TAT: 5 business days

  1. Protein amplification express and purification

To optimize and obtain the genes with appropriate expression condition and use 1L or greater culture scale to induce and express recombinant bacteria. After the culture and induction, affinity purification or ion exchange, hydrophobic gel and multi-step purification (optional or alternative) are further conducted. It is tacitly approved that SDS-PAGE tests purity and Western blot tests accuracy (optional, the customer provides verified first antibody).

Delivery contents: 1-10mg recombinant proteins and purification report data

Delivery TAT: 10-15 business days

  1. Protein post processing (optional)

For those proteins with further special requirements, Synbio Tech. provides you a variety of post processing options, including protein tag removal after purification, filtration sterilization, endotoxin removal, freeze-dry, N-terminal sequencing and other services.

Delivery contents: inquiry

Delivery TAT: inquiry

How to order

+1 732-230-3003
+1 609 228 5911
Online Inquiry
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