Wheat Germ Extract (WGE) Cell-Free Protein Synthesis for High-Throughput Screening and Labeling

The Wheat Germ Extract (WGE) Cell-Free Protein Synthesis (CFPS) System is one of the most widely used eukaryotic in vitro translation platforms. Derived from the dormant embryo of the wheat kernel, WGE lysate contains the complete ribosomal machinery, transfer RNAs (tRNAs), and initiation/elongation factors necessary for protein synthesis. Critically, the lysate is naturally low in endogenous mRNA and proteins , resulting in minimal background noise and high purity in the final product.

CD Biosynsis offers a high-yield WGE CFPS Service renowned for its exceptional suitability for High-Throughput Screening (HTS) and stable isotope labeling . WGE delivers highly active, functional eukaryotic proteins, often achieving higher yields than other plant or animal-based systems. Its low background makes it the ideal choice for experiments requiring sensitive detection, incorporation of non-natural amino acids (nnAAs), or uniform labeling for NMR structure determination .

Highlights

Key advantages of choosing the WGE CFPS System:

• Extremely Low Background: Minimal endogenous protein and mRNA contamination, crucial for NMR and labeling studies.
• High Protein Yields: Recognized for producing large amounts of protein, often exceeding other eukaryotic CFPS systems, particularly for smaller to medium-sized proteins.
• Robust and Fast: Supports rapid protein synthesis (hours) and exhibits high stability, making it excellent for automation and HTS.
• Supports Functional Folding: Contains necessary eukaryotic chaperones for the correct folding of many complex proteins, although its PTM capability is more limited than HEK293.

Applications

Critical applications where WGE CFPS provides speed, purity, and sensitivity:

High-Throughput Screening (HTS)

Automated synthesis and screening of thousands of protein mutants, small molecule targets, or siRNA library members in micro-well plates.

Stable Isotope Labeling (NMR)

The system's low background enables highly efficient and cost-effective incorporation of 15N, 13C, or 2H precursors for structural NMR analysis.

Production of scFv and Fab Fragments

Rapid synthesis of functional antibody fragments, VH/VL domains, and other multi-cysteine proteins for binding studies.

Non-Natural Amino Acid Incorporation

Allows for highly efficient incorporation of nnAAs with low competition from endogenous amino acids for protein functionalization.

Key Features & Comparisons

WGE CFPS compared to other eukaryotic systems (RRL and HEK293):

Optimal for NMR Labeling

The minimal metabolic background is crucial for achieving uniform and high-fidelity stable isotope labeling.

High Productivity (Yield)

WGE ribosomes exhibit superior stability and turnover, often yielding 100s of ug/mL of protein in continuous exchange mode.

PTM Capability (Limited)

Naturally lacks complex glycosylation, but is effective for phosphorylation and can be supplemented for disulfide bond formation.

Low Endogenous Nuclease

Lower ribonuclease (RNase) activity than RRL, leading to better stability and longevity of the mRNA template.

Cost-Effective Scaling

The lysate source (wheat) is abundant, making large-scale preparative synthesis more economically viable than RRL or HEK293.

Workflow

Our systematic approach for high-purity WGE CFPS protein production:

• Template Preparation: The gene is supplied, and we prepare high-quality cDNA or in vitro transcribed capped mRNA template.
• Reaction Setup: The template is combined with the high-activity WGE lysate, energy mix, and labeling precursors (if required).
• In Vitro Synthesis: The reaction is incubated at an optimal temperature (25°C-30°C) for batch or continuous exchange mode synthesis.
• Purification and Quality Control (QC): Purification via affinity chromatography is performed. QC includes SDS-PAGE, protein quantification, and MS or NMR verification of labeling efficiency.
• Delivery: Delivery of purified protein confirmed for high purity, accurate labeling, and native function, along with detailed COA.

We provide essential assurance for high-quality WGE expression outcomes:

• Guaranteed Purity and Yield: We ensure the protein meets customer purity specifications (typically >90%) and guaranteed minimum yield.
• High Labeling Efficiency: Confirmed near-perfect incorporation of isotopic precursors for structural biology studies.
• Functional Verification: Assistance with downstream functional assays to confirm biological activity.
• Scalability: Expertise in scaling WGE CFPS from micro-well plate HTS to multi-milligram preparative scale.