Development of an Autoinducible Plasmid for Recombinant Protein Production

Area of Science:

• Molecular Biology
• Biotechnology
• Protein Expression

Background:

• Recombinant protein production in E. coli relies on specific host strains, vectors, media, and induction methods.
• Conventional methods often involve complex procedures and specialized reagents, posing challenges for routine protein production.
• Optimizing each step, from gene insertion to maximizing yield, is crucial but can be resource-intensive.

Purpose of the Study:

• To develop a simplified system for recombinant protein production using easily accessible materials.
• To reduce the time and effort required for routine protein expression work.
• To create a plasmid that eliminates the need for specialized E. coli strains or expensive media.

Main Methods:

• Constructed an expression plasmid with a hybrid autoinducible promoter system.
• Replaced the lethal barnase gene with sacB and inserted reporter genes (mCherry, MBP, GST).
• Selected the optimal plasmid based on cell pellet color intensity and compared protein yields.

Main Results:

• Developed an expression plasmid with an autoinducible promoter functional in standard E. coli hosts and TB medium.
• The plasmid features a color indicator, turning red upon successful protein production.
• Achieved protein yields for maltose-binding protein (MBP) and glutathione S-transferase (GST) comparable to specialized systems.

Conclusions:

• A novel plasmid was engineered with a hybrid, stationary-phase-activated autoinducible promoter.
• This system negates the requirement for specialized E. coli strains or complex media.
• The colorimetric indicator serves as a reliable predictor of successful protein production and yield.