1. High-throughput screening
High-throughput screening (HTS) has been widely used in drug discovery, genetic engineering, proteomics, and other fields, and has always been an important tool to promote scientific progress. It can quickly screen out substances with specific activities or functions from a large number of compounds or gene sequences in a short time, which greatly accelerates the research process, improves the efficiency of scientific research, and reduces the cost of research and development.
Figure 1: High-throughput screening strategies to facilitate the synthesis of related products in microbial cell factories.
However, with the increasing demand of scientific research and industry, the disadvantages of traditional high-throughput screening techniques have become increasingly apparent, such as the problem of screening efficiency and accuracy. Traditional screening methods often rely on chemical or biological methods, which can be affected by various factors, such as the quality of the sample, the control of experimental conditions, etc., which can affect the accuracy and efficiency of screening.
2. Cell-free protein expression
As a promising biotechnology, cell-free protein expression (CFPS) technology has been rapidly developed in recent years and gradually applied to the field of high-throughput screening. This technique is an in vitro recombinant protein expression technique in which protein synthesis is performed in vitro with cell lysates containing essential components of protein synthesis (ribosomes, transport RNA, aminoacyl synthetase, initiation elongation stop factor, ATP, Mg2+ and K+, etc.).
Figure 2: Cell-free expression system.
Source: team: Hong Kong-cuhk description -2017igem.org
Compared with traditional cell-based high-throughput screening techniques, cell-free protein synthesis avoids many of the problems of traditional technologies, such as low expression efficiency, difficult protein purification, and cytotoxicity, because it does not require a cell-based system. The advantages are also obvious, such as:
1. High efficiency: Cell-free protein expression technology can achieve large-scale protein preparation in a short time, which greatly improves the screening efficiency.
2. High purity: The purity of cell-free protein expression technology can reach 90%, which meets the requirements of industrial production.
3. Flexibility: Cell-free protein expression technology can optimize the expression system by adjusting reaction conditions or reactants, providing greater flexibility for scientific research and industrial applications.
Figure 3: Time vs. reagent cost analysis of the cell-free protein expression screening process.
1.Rapid screening.
With cell-free protein expression systems, researchers can quickly screen for potentially active substances or proteins with specific functions from a large number of compounds or sequences in a very short period of time. This will greatly improve the efficiency and accuracy of screening, and accelerate the process of new drug discovery and genetic engineering. Cell-free protein synthesis has been shown to be a promising method for screening membrane protein targets in a variety of lipid mimics, and they report a high-throughput screening workflow that has been applied to screen 61 eukaryotic membrane protein targets.
Figure 4: Workflow for high-throughput cell-free screening of membrane proteins.
2.Large-scale protein preparation.
Cell-free protein synthesis systems have emerged as promising platforms to accelerate protein design, biomanufacturing, and testing. With the maturity of cell-free protein synthesis technology, the cost and time required to prepare reactions have decreased, and it has been reported that protein yields can be increased to grams per liter of reaction volume through cell-free protein synthesis systems. Current cell-free systems offer some distinct advantages over large-scale protein preparation over cellular expression. For example, CFPS reactions have excellent speed and flexibility in screening activities, as they can generate proteins from linear DNA templates in a matter of hours, avoiding rate-limiting transformation or transfection procedures.
3.Drug discovery.
Cell-free protein expression technology enables the rapid synthesis of drugs with specific functions, such as anti-tumor and antiviral drugs, which provides strong support for new drug development and personalization**. Currently, CFPS systems tailored for the production of proteins with post-translational modifications have been developed, opening the door to cell-free biomanufacturing of **sexual proteins. CFPS can tightly control the molecular environment in which proteins are expressed, allowing users to study and optimize site-specific protein modifications that are often critical for proper folding and biological activity of drugs and vaccines. In addition, CFPS extracts can be prepared from a range of different culturable cell lines, enabling users to take advantage of strain-specific endogenous (or heterologous) biological mechanisms. As a result, CFPS systems are now capable of producing products such as antibodies, antibody fragments, multi-subunit enzymes, and conjugate vaccines.
4.Industrial production.
The assembly of CFPS reactions can be automated and adapted using liquid handling systems, increasing throughput for protein expression, optimization, and characterization. It meets the demand for high-yield, high-purity proteins in industrial production. Innovate UK funded a project that brought together companies CPI, IPSEN BIOPHARM and Touchlight Genetics to produce proteins (e.g. recombinant botulinum toxin) that were toxic to host cells and/or production personnel using an industrial-scale CFPS reaction that complied with good manufacturing practices.
Fourth, the outlook:
In conclusion, high-throughput screening plays a vital role in scientific research and industrial applications. As an emerging solution, cell-free protein expression systems are gradually overcoming the efficiency and accuracy issues faced by traditional high-throughput screening, and bringing more possibilities to scientific research and industry. Let's look forward to greater achievements in future scientific research and industrial development for cell-free protein expression.
As a professional cell-free protein expression biotechnology company, Perotin Biotech has a professional technical team composed of national high-level leading talents, returnee doctors and other talents, relying on independent research and development and unique cell-free protein expression technology platform, specializing in the research and development of peptides, recombinant proteins, genetically engineered antibodies, recombinant vaccines and macromolecular protein drugs, and at the same time providing cell-free protein expression products, protein raw materials and reagents and customized services for the majority of biomedical enterprises and research institutions.
Technical exchange: wwwcellfreeprotein.cn
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