Recombinant Protein Expression Services

E.coli Cell-Free Expression System—SLC7A11 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 System—ALPI 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 System—POLQ 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