T7 Phage Display Peptide Library Screening Platform
T7 phage display library is a system based on T7 phage display technology, which is used to display peptides or proteins. The head of phage T7 contains double-stranded DNA. Its genome is highly stable and easy to operate, so it is a preferred vector for constructing phage display libraries. With the help of genetic engineering technology, the sequence encoding random peptides can be integrated into the genome of T7 phage, so that each phage particle can display specific peptides on its capsid protein. Through phage display screening techniques, these libraries are able to identify peptides or proteins with desired properties.
The core of T7 phage display library
Phage T7, as a virus, has been widely used in molecular biology experiments. It is favored because of its short replication cycle, large vector capacity and efficient expression system.The core idea of phage display technology is to fuse exogenous peptides or protein fragments with phage shell proteins ( such as gene 3 protein of T7 phage ) by genetic engineering, so that peptides or proteins are presented on the surface of phages in the form of ' display '. In this way, each phage particle in the display library will carry a specific peptide sequence to form a diverse peptide library.
The construction of T7 phage display peptide library
The construction of T7 phage display peptide library usually depends on the insertion of the DNA sequence of the peptide library into the T7 phage genome, and the phage particles displaying the peptide are generated by transformation or transfection. Each phage particle in the peptide library represents a peptide sequence. Therefore, the entire phage display library can cover an extremely rich peptide sequence library and is suitable for a wide range of biological screening.
T7 phage display library screening steps
Construction of the library
The gene sequence of the peptide library was constructed by chemical synthesis or synthetic gene synthesis technology. Each peptide sequence is made up of randomly encoded oligonucleotides, which allow the peptide library to be screened to generate millions or even billions of different peptide sequences. These peptide sequences were cloned into the genome of T7 phage, and they were fused with the capsid protein of the phage to construct a diversified phage display library. This library has the ability to support phage display screening and high throughput screening.
Screening target molecules
During the phage display screening process, the T7 phage display library undergoes affinity-based peptide library screening with target molecules (such as antibodies, receptors, or small-molecule drugs). This process, enhanced by high throughput screening, often involves immobilizing target molecules on solid-phase carriers (such as magnetic beads or microplates). The phages in the phage display library were then incubated with the target molecules. Only those phages that can specifically bind to the target can survive, which strongly verifies the accuracy of phage display screening and high throughput screening. Subsequently, the phages that did not bind to the target molecule were removed by washing steps.
In the process of screening target molecules, the T7 phage display screening method mainly focuses on the use of affinity-based peptide library screening to identify peptides with high specificity. In this process, the target molecule is fixed, and the T7 phage is incubated with the target molecule using a high throughput screening method, only those phages with strong binding affinity are screened.
2018-07-16
