ALFA-Tag Peptide

The ALFA-tag peptide, with the sequence Cys-PSRLEEELRRRLTEP-Amide, is a meticulously engineered 15-amino-acid epitope tag designed to enhance the detection, purification, and manipulation of target proteins in both prokaryotic and eukaryotic systems. Its unique structure and properties make it an invaluable asset in modern bioscience applications.

Key Features and Functions:

• Optimized Design: The ALFA-tag is a rationally designed epitope tag (SRLEEELRRRLTE) that forms a small and stable _-helix, functional irrespective of its position on the target protein in prokaryotic and eukaryotic hosts. 

• High-Affinity Binding: The ALFA-tag is recognized by a high-affinity single-domain antibody (NbALFA) with a dissociation constant (K_D) of approximately 27 pM, ensuring stable and specific interactions for various applications. 

• Versatile Applications: The ALFA system enables high-resolution imaging in live or fixed cells, efficient immobilization and affinity purification of functional proteins and complexes, and potential therapeutic applications, all facilitated by the ALFA-tag’s compatibility with various detection methods. 

• Compatibility with Nanobody Technology: The ALFA-tag is specifically recognized by nanobodies, such as NbALFA, which are single-domain antibodies known for their small size and high specificity. This compatibility allows for applications in super-resolution microscopy, live-cell imaging, and intracellular protein manipulations. 

Biological Importance in Research:

The ALFA-tag system addresses limitations of traditional epitope tags by offering a compact, stable, and highly specific tagging solution. Its design minimizes interference with protein function, making it ideal for studying protein localization, interactions, and dynamics within cells. The high-affinity binding to nanobodies facilitates precise detection and purification, enhancing the reliability and efficiency of experimental outcomes.

Incorporating the ALFA-tag peptide into research protocols empowers scientists with a robust tool for protein analysis, contributing to advancements in molecular biology, biochemistry, and related fields.

ALFA-Tag Peptide is a 15-residue synthetic peptide with the sequence Pro-Ser-Arg-Leu-Glu-Glu-Glu-Leu-Arg-Arg-Arg-Leu-Thr-Glu-Pro. C-terminal amidation removes the terminal carboxylate charge. The sequence contains 0 Lys and 4 Arg residues, contributing cationic character. These sequence-derived properties describe the reagent chemically; no specific receptor, enzyme, pathway, disease association, or biological activity is assigned without product-specific experimental evidence.

• LC-MS/HPLC analytical method development
• sequence-specific assay controls

Sequence-derived chemical properties support reagent selection and experimental planning but do not establish biological function. Solubility, aggregation, adsorption, conjugation efficiency, and assay performance should be validated under the intended experimental conditions.