Chemical synthesis, in vivo expression, and cell-free protein synthesis are the three main strategies for protein production. Chemical synthesis is not practical for the synthesis of long peptides, and protein expression in vivo can only produce proteins that do not affect the physiological function of the host cell. In contrast, cell-free expression systems can synthesize proteins with high accuracy and at speed approaching in vivo rates, and can express proteins that interfere with cell physiology.
Cell-free protein expression plays an important role in biochemical studies and protein high throughput production. Common cell-freer expression systems are derived from E. coli extract, wheat germ extract, and rabbit reticulocyte lysate. Wheat germ system provides the highest translation efficiency among the eukaryotic systems and has a very high success rate for the expression of high-quality soluble proteins. As an in vitro protein expression method, the wheat germ system is a preferable choice for many applications in protein research including options for protein labeling and the expression of difficult-to-express proteins such as membrane proteins and multiple protein complexes.
The wheat grain consists of the bran, endosperm, and germ. Since the germ is in a dormant stage, it is extraordinarily rich in protein factors and ribosomes that are necessary for rapidly performing protein synthesis from stored mRNAs during early germination. In addition, eukaryotic ribosomes from plants are better adapted for protein folding during synthesis than prokaryotic ribosomes from E. coli extracts.
According to research findings, the extremely low translation activity of wheat germ expression system was due to the presence of translation inhibitors in the reaction solution. In 2000, the wheat germ cell-free protein expression system (ENDEXT) technology was developed, which greatly improves synthesis by removing translation inhibitors originating in the germ.
|Vectors||pEU Vector set||Highly optimized to maximize synthetic efficiency|
|Wheat Germ Extracts||WEPRO7240||Containing an abundance of the translation factors that are required for protein synthesis|
|WEPRO7240G||GST-tagged protein recommendation|
|WEPRO7240H||His-tagged protein recommendation|
|WEPRO8240||Optimized for stable isotope labeled protein synthesis|
|WEPRO8240G||GST-tagged protein recommendation|
|WEPRO8240H||His-tagged protein recommendation|
|Translation Buffers||SUB AMIX SGC||Dedicated for WEPRO7240 series|
|SUB AMIX SGC NA||Dedicated for WEPRO8240 series|
|SUB AMIX SG||Dedicated for WEPRO7240 series (optimized for filter&feed method)|
|SUB AMIX SG NA||Dedicated for WEPRO8240 series (optimized for filter&feed method)|
|Transcription Buffers||5×Transcription Buffer LM||Transcription reaction mixture for WEPRO7240 and 8240 series|
|Liposomes||Asolectin Liposome, lyophilized||Used for membrane protein expression|
The synthesis of the target protein takes at least 4 days when a PCR product is used as template DNA and at least 10 days when the vector is used.
Wheat germ extract has high protein synthesis activity, and the method of protein synthesis is important to maximize its benefit. A proprietary technology has been developed to solve the problems of conventional methods such as the batch method and the dialysis method. Bilayer method provides high yield proteins by forming two layers in the form of wheat germ extract and substrate solution so that substrates are slowly diffuse and dispersed through the contact surface.
Bilayer method can be fully automated for large-scale and efficient screening. Its flexible format permits screening different additives for the translation reaction, such as detergents or lipids for the expression of membrane proteins in a soluble form. Moreover, bilayer method has higher synthetic efficiency than the batch method, where substrates are completely consumed within a few hours and the reaction stops. Although protein production is higher in the dialysis mode, the cost is proportionally higher in the case of protein labeling because of the larger buffer volume.
|Batch Method||Dialysis Method||Bilayer Method|
|Characteristics||All reagents are mixed in the reaction solution.||The reaction takes place in the dialysis device.||Two layers are formed in the reaction solution.|
|Operability||Easily synthesizing multiple samples||Not suitable for synthesizing multiple samples||Easily synthesizing multiple samples|
|Yield||The synthesis efficiency and yield are low, because the substrates are completely consumed within a few hours.||The synthesis efficiency and yield are high, because the dialysis buffer containing fresh substrates can diffuse in, while byproducts passively diffuse out.||The synthesis efficiency and yield are high, because the substrates substrate buffer is overlaid onto the translation mixture, allowing for a diffusion-controlled translation process.|
*Our products can also be used to synthesize target proteins using the dialysis method.
In addition to natural proteins, the wheat germ cell protein-free expression system can also be used to express artificial proteins, such as preparing stable isotope-labeled peptide libraries. The wheat germ system can be compatible with high-resolution structural biology methods such as cryo-electron microscopy (cryo-EM), X-ray crystallography, solution nuclear magnetic resonance (NMR), and solid-state NMR. The unique possibilities of the system for studying cytotoxic proteins, complex membrane proteins or molecular assembly in a native-close state create opportunities for structural approaches to study complex proteins.
|Premium ONE Expression Kit||Used to confirm the expression of target proteins in a short time|
|Premium PLUS Expression Kit||Used to confirm the expression of target proteins and to synthesize protein on a small scale easily|
|Protein Research Kit S16||Used to synthesize all types of proteins|
|Protein Research Kit G16||Used to synthesize all types of proteins (GST-tagged protein recommendation)|
|Protein Research Kit H16||Used to synthesize all types of proteins (His-tagged protein recommendation)|
|WEPRO7240 Core Kit||Used to synthesize all types of proteins|
|WEPRO7240G Core Kit||Used to synthesize all types of proteins (GST-tagged protein recommendation)|
|WEPRO7240H Core Kit||Used to synthesize all types of proteins (His-tagged protein recommendation)|
|Disulfide Bond PLUS Expression Kit||Intended to make proteins having disulfide bonds|
|Disulfide Bond Enhancer Enzyme Set||Intended for use in combination with WEPRO7240H Core Kit to make proteins having disulfide bonds|
|WEPRO8240 Core Kit||Used to synthesize stable isotope labeled proteins|
|WEPRO8240G Core Kit||Used to synthesize stable isotope labeled proteins (GST-tagged protein recommendation)|
|WEPRO8240H Core Kit||Used to synthesize stable isotope labeled proteins (His-tagged protein recommendation)|
|FLEXIQuant PLUS Expression Kit||Used to make full-length isotope-labeled MS Standards|
|Premium PLUS Expression Kit for MS||Used to synthesize 13C and 15N stable isotope- labeled proteins|
|WEPRO8240 (15N) Core Kit||Used to synthesize stable isotope 15N labeled proteins|
|WEPRO8240G (15N) Core Kit||Used to synthesize stable isotope 15N labeled proteins (GST-tagged protein recommendation)|
|WEPRO8240H (15N) Core Kit||Used to synthesize stable isotope 15N labeled proteins (His-tagged protein recommendation)|
|WEPRO8240 (13C, 15N) Core Kit||Used to synthesize stable isotope 13C and 15N labeled proteins|
|WEPRO8240G (13C, 15N) Core Kit||Used to synthesize stable isotope 13C and 15N labeled proteins (GST-tagged protein recommendation)|
|WEPRO8240H (13C, 15N) Core Kit||Used to synthesize stable isotope 13C and 15N labeled proteins (His-tagged protein recommendation)|
|ProteoLiposome PLUS Expression Kit||Used to synthesize membrane proteins|
|ProteoLiposome BD Kit||Suitable for large-scale production of membrane protein|
|Wheat germ cell-free||E. coli cell-free||E. coli||Insect cell||Yeast||CHO cells|
|Species range of proteins that can be expressed||★★★||★☆☆||★☆☆||★★☆||★★☆||★★☆|
|Ease of operation||★★★||★★★||★★☆||★★☆||★★☆||★★☆|
|Total work time||3-10 days||9 days||2 weeks~||5 weeks~||3 weeks~||2 weeks~|