Tamavidin, a versatile affinity tag for protein purification and immobilization

Area of Science:

• Biochemistry
• Protein Engineering
• Biotechnology

Background:

• Avidin and streptavidin, common biotin-binding proteins, exhibit poor solubility in E. coli.
• Tamavidin 2, a fungal avidin-like protein, demonstrates high-affinity biotin binding and soluble expression in E. coli.

Purpose of the Study:

• To develop an efficient system for one-step purification and immobilization of recombinant proteins using tamavidin 2 as an affinity tag.
• To evaluate the efficacy of tamavidin 2 fusion technology for high-level expression and purification of target proteins.

Main Methods:

• Fusion of target proteins (bacterial sialyltransferase, soybean agglutinin) to tamavidin 2.
• Expression of fusion proteins in Escherichia coli and tobacco BY-2 cells.
• Immobilization and purification using biotinylated magnetic microbeads.

Main Results:

• High-level soluble expression of fusion proteins achieved (80 mg/L in E. coli, 2 mg/L in BY-2 cells).
• Tamavidin 2 fusion proteins were tightly immobilized and highly purified (90-95%) on microbeads with minimal activity loss.
• Longer biotin linkers enhanced the affinity between fusion proteins and biotin.

Conclusions:

• Tamavidin fusion technology provides a powerful and efficient method for recombinant protein production, purification, and immobilization.
• This system overcomes the solubility limitations of traditional biotin-binding proteins.
• Tamavidin 2 is a promising alternative affinity tag for biotechnological applications.