High-yield membrane protein expression from E. coli using an engineered outer membrane protein F fusion

Area of Science:

• Structural Biology
• Biophysics
• Protein Expression

Background:

• High yields of membrane proteins are crucial for structural studies but challenging due to poor solubility and variable expression.
• Existing heterologous expression systems often struggle to produce sufficient quantities of functional membrane proteins.

Purpose of the Study:

• To develop an improved system for high-yield overexpression of full-length membrane proteins.
• To enable detailed structural and biophysical characterization of membrane proteins.

Main Methods:

• Engineered an Escherichia coli-based system using a fusion with outer membrane protein F (pOmpF).
• Expressed full-length human receptor activity-modifying protein 1 (RAMP1) using the pOmpF fusion system.
• Solubilized and purified RAMP1 using FC15 detergent and assessed its structure and solubility via spectroscopy.

Main Results:

• Achieved high-yield overexpression of full-length RAMP1.
• Purified RAMP1 demonstrated high α-helical content (~90%) and maintained solubility and structure in FC15 across a broad temperature range (20-60°C).

Conclusions:

• The developed pOmpF fusion system is effective for high-yield, full-length membrane protein overexpression.
• This approach facilitates the production of soluble and structurally stable membrane proteins for biophysical and structural studies.