Avi-tagged Proteins

How Avi-Tagging Works?

To create Avi-tagged proteins, the Avi tag sequence is added to the protein's genetic code via recombinant DNA technology. Once expressed in a host system, the protein can be biotinylated in vivo (inside living cells) or in vitro (outside the cells) using the BirA enzyme.

The Avi tag protein expression allows researchers to produce large quantities of tagged proteins with precise control over the biotinylation process. By tagging the protein with the Avi sequence, biotin can be efficiently added at specific locations on the protein, enabling easy purification and detection without affecting the protein’s natural properties.

Key Features of Avi-Tagged Proteins:

• Highly Efficient Biotinylation: The BirA enzyme catalyzes biotinylation with high specificity and efficiency, ensuring that nearly every protein produced is biotinylated.
• Versatile Applications: Avi-tagged proteins are useful in applications like affinity purification, drug screening, and identifying protein interactions.
• Minimal Impact on Protein Function: The small Avi tag does not significantly interfere with the protein’s structure or function, allowing for accurate biological studies.
• Simple Integration: The Avi tag sequence can be easily incorporated into the N- or C-terminus of the target protein without disrupting its functional domains.

Applications of Avi-Tagged Proteins

The versatility of Avi-tag proteins has made them indispensable tools in various research fields. Some of the key applications include:

• Protein Purification: Avi-tagged proteins can be purified using streptavidin-coated beads, which bind to the biotin tag. This process enables efficient isolation of the protein of interest, even from complex mixtures.
• Detection and Assays: Biotinylation makes it easy to detect Avi-tagged proteins using biotin-binding molecules like streptavidin, enabling their use in assays such as ELISA, Western blotting, and flow cytometry.
• Protein Interaction Studies: The biotinylation allows researchers to easily capture target proteins and analyze their interactions with other proteins, DNA, or small molecules in a variety of assays.
• Cell-Based Studies: Avi tag amyloid proteins are of particular interest in Alzheimer's disease and other neurodegenerative disorders. The tag allows for the precise labeling of amyloid proteins, enabling the study of their aggregation and interaction with cellular structures in vitro.
• Biosensor Development: The biotin-avidin interaction is commonly used in the development of biosensors, where Avi-tagged proteins can be immobilized onto surfaces for high-sensitivity detection of target molecules.

Advantages of Using Avi-Tagged Proteins

• Efficiency: The biotinylation process is highly efficient, leading to nearly 100% biotinylation of the tagged protein. This is crucial for studies where precise and reproducible results are required.
• Specificity: The Avi tag sequence enables highly specific binding to biotinylated ligands such as streptavidin, providing a robust method for protein purification and detection.
• No Need for Affinity Tags: Because biotin-streptavidin binding is so strong, researchers do not need to rely on other affinity tags that might affect the protein’s behavior or interactions.
• Non-Invasive: The Avi tag is a small peptide, which means it does not significantly alter the structure or function of the protein, making it suitable for studies of native protein behavior.
• Wide Range of Applications: From basic protein research to complex clinical applications, Avi-tag proteins can be used in a variety of fields, from structural biology to therapeutic development.

Protein Expression with Avi Tags

Avi tag protein expression is typically carried out in expression systems like E. coli, yeast, or mammalian cells. These systems can support high yields of protein, allowing for extensive studies. The Avi tag is incorporated into the protein either during the cloning process or added as a post-translational modification.

For biotinylation in vivo, the host cell must express the BirA enzyme to catalyze the addition of biotin to the Avi tag. Alternatively, in vitro biotinylation can be performed using purified BirA enzyme and the biotin donor molecule. Both methods result in high-efficiency biotinylation of the target protein.

Why Choose Beta LifeScience for Avi-Tagged Proteins?

At Beta LifeScience, we provide high-quality Avi-tagged proteins that are ready for your research applications. Our products undergo rigorous quality control to ensure:

• Purity: We use optimized expression systems and purification protocols to ensure the purity of our Avi-tagged proteins.
• Consistency: Our proteins are produced under strict conditions to ensure that each batch meets the same high standards, providing reproducible results.
• Reliability: With our expertise in protein engineering, we offer customized solutions to fit your specific research needs.

When you choose Beta LifeScience, you gain access to cutting-edge tools that will help you advance your research in protein expression, purification, and beyond.

FAQs

What is an Avi tag on proteins?

An Avi tag is a short peptide sequence, typically composed of 15 amino acids, that is added to a protein of interest. The tag enables biotinylation through the action of the BirA biotin ligase enzyme, which covalently attaches a biotin molecule to the tag. This allows the protein to be easily purified, detected, and studied using biotin-binding molecules such as streptavidin.

Why isn’t my protein being biotinylated in vivo with the Avi tag?

There could be several reasons why Avi-tag protein biotinylation isn’t occurring as expected in vivo:

• Lack of BirA enzyme: Ensure that the host cells are expressing the BirA biotin ligase enzyme, which is necessary for biotinylation.
• Poor expression levels: If the protein is not being expressed in sufficient quantities, biotinylation may not occur at an effective level.
• Inappropriate host system: Some host cells may not have the optimal machinery for biotinylation. Consider using different expression systems, such as mammalian cells or yeast.

What is the Avi tag protein sequence?

The Avi tag protein sequence is typically a 15 amino acid peptide, which is recognized and biotinylated by the BirA biotin ligase. The exact sequence is: GLNDIFEAQKIEWHE.

This sequence is added to the N- or C-terminus of the protein to enable biotinylation.

Can I use the Avi tag for proteins in non-mammalian systems?

Yes, Avi tag protein expression is compatible with a variety of expression systems, including E. coli, yeast, and mammalian cells. The versatility of the Avi tag makes it suitable for a wide range of applications, from basic research to industrial-scale protein production.

What are Avi tag amyloid proteins used for?

Avi tag amyloid proteins are commonly used in the study of neurodegenerative diseases like Alzheimer’s. The Avi tag enables easy detection and purification of amyloid proteins, which are involved in the formation of plaques in the brain. This allows researchers to study amyloid aggregation and interactions with other proteins or molecules in detail.