Recombinant Protein Expression Services

Recombinant proteins are encoded by recombinant DNA cloned in a system that supports gene expression and translation. The host cells for recombinant protein production can be bacteria, mammalian cells, insects, and yeast. Recombinant proteins have been used in hot research areas such as immune checkpoints, antibody-drug targets, CAR-T cell therapy, Fc receptors, influenza viral proteins, and cytokines.

Our one-stop customization platform ensures the delivery of high-yield and purity products in the most flexible, cost-effective manner possible within the shortest time frame. We look forward to collaborating with scientists worldwide to accelerate scientific discoveries.

  • One-stop service
    from gene design to
    protein preparation

  • Independent
    research and
    development of a variety of high-expression vectors and strains

  • Professional R & D
    team of recombinant
    protein technologies

  • Providing customized
    services of high-purity
    proteins from mg to g

  • Large-scale protein
    production platform

Service Process

MedChemExpress (MCE) provides a one-stop service from genes to proteins. Customers can flexibly choose services or personalized services according to their own needs.

  • 01 Codon
  • 02 Gene
  • 03 Construction of
    Expression Vector
  • 04 Strain
  • 05 Protein
  • 06 Purification
    & QC
  • 07 Protein

Information needed from customers

Amino acid sequences

Final Delivery

Target proteins Plasmid (optional) Project report, or QC report

Things to note:

01.  Except for a smaller number of expression high risk proteins, most proteins are risk-free customization: there is no charge if there is no expression, without any upfront payments.

02.  The number of amino acids is not restricted, and specific proteins need to be explicitly evaluated.

03.  If, due to the protein’s intrinsic properties, the quality and purity do not meet the requirements after attempts and there is no need to deliver the protein, only the prepaid fee (if any) will be charged.

04.  Strict quality control is enforced, with default internal toxin levels at <1 EU/μg and purity greater than 90% (some proteins can reach more significant than 95%). If the estimated purity is below 90% due to protein characteristics, this will be communicated during evaluation, and the customer can decide whether to continue.

Expression System Selection Guide

E.coli Cell-Free Yeast Mammalian Insect
Prokaryotic Eukaryotic Eukaryotic Eukaryotic
High yield
Wide range of applications
Few steps
Short cycle
High throughput
Partial PTM
Closer to natural protein
Lower endotoxins
Better activity
More complex PTM
Large gene
Soluble protein
PTM is similar to the mammalian system
Easy to form inclusion bodies
No PTM (like glycosylation)
High endotoxin levels
Large molecular weight proteins
May not fold correctly
Low secretion efficiency Long cycle
Higher cost
Long cycle
Higher cost
Lack of partial glycosylation
Bacterial proteins
Antigen proteins
Toxic proteins
Multi-pass transmembrane proteins
Small molecular protein
Secreted proteins
Extracellular domain of transmembrane proteins
Recombinant antibodies
Antibody fragments
Cytoplasmic proteins
Toxic proteins
Transmembrane proteins
Secreted proteins
More More More More More

Cases Sharing

E.coli Cell-Free Expression SystemSLC7A11 Protein, Human (Multi-pass membrane protein)

Challenge: Multi-pass transmembrane proteins have high hydrophobicity, low expression levels, and high purification difficulty, making it challenging to obtain a soluble protein.

Preparation process: Protein synthesis is achieved by adding DNA templates, ATP, amino acids, various substrates, and enzymes from cell extracts in vitro. The target protein is then extracted by screening different detergents. So far, we have found that Brij78, FOS12, and DDM are effective detergents that can dissolve and purify membrane proteins well and help them form the correct natural conformation in solution.

Target protein purification profile and QC gel

Activity validation

Mammalian Expression SystemALPI Protein, Human(Glycosylation)

Advantages: Mammalian systems possess complex PTM, such as glycosylation. Regarding molecular structure, physical and chemical properties, and biological functions, proteins expressed in mammalian cells are the closest to natural proteins.

Preparation process: Based on the target protein’s sequence, we analyze and optimize factors such as rare codons and codon preferences, then perform complete gene synthesis. Once the sequencing is correct, the gene is cloned into a specialized high-expression vector. After confirming that the plasmid meet the requirements for transfection, an appropriate transfection method and host cells are chosen for the process. Upon completion of transfection, a suitable purification method is selected in combination with advanced equipment to purify the protein.

Target protein purification profile and QC gel

Activity validation

Insect Expression SystemPOLQ Protein, Human(988a.a, Large molecular weight protein)

Challenge: Large molecular-weight proteins are difficult to secrete, have lower expression levels, and are challenging to purify.

Preparation process: We optimize the codons based on the target protein’s sequence , synthesize the target gene, and subclone appropriate baculovirus vector for transfection into insect cells to obtain P0 generation. Then, protein expression levels are determined through electrophoresis. If necessary, we infect cells with the P0 generation to produce the P1-P2 generation. After infecting insect cells with P1 or P2 generation, we purify the target protein using various chromatography methods such as affinity, ion exchange, hydrophobic interaction, and size exclusion.

MW: 103.1 kDa

Target protein QC gel

Bulk and Custom Product Services

Each project of recombinant protein customization requires evaluation to determine the corresponding plan and price. For further information on service prices or technical details, please send an email to Or call 609-228-6898 to contact us directly.

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Inquiry Information

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