A novel system for stable, high-level expression from the T7 promoter

Area of Science:

• Molecular Biology
• Biotechnology
• Protein Expression Systems

Background:

• The T7 phage polymerase and promoter (T7 p/p) system is a widely used prokaryotic expression system.
• A key limitation is the decline in target protein expression after a few subcultures.
• This instability hinders large-scale recombinant protein production.

Purpose of the Study:

• To develop a stable, high-level expression system for T7 RNA polymerase-based expression.
• To overcome the inherent instability of the traditional T7 p/p system.
• To enable industrial-scale applications of T7 p/p expression.

Main Methods:

• Designed and created a novel expression cassette for the T7 p/p system.
• Tested the cassette with two different vector backbones.
• Evaluated expression levels using two distinct target proteins.

Main Results:

• The new expression cassette demonstrated stable and high-level protein expression.
• Consistent results were observed across different vector backbones and target proteins.
• The novel system significantly outperformed the traditional T7 p/p system in stability and expression levels.

Conclusions:

• A universal expression cassette has been developed for stable, high-level protein expression in T7 RNA polymerase systems.
• This cassette serves as a novel expression platform, addressing the primary deficiency of the T7 p/p system.
• The developed method facilitates the industrial-scale application of the T7 p/p system.