MDYKDHDGDYKDHDIDYKDDDDK Peptide – Catalog #B2026675

MDYKDHDGDYKDHDIDYKDDDDK (Catalog #B2026675) is a 24-amino-acid synthetic peptide with a molecular weight of 2861.87 Da. The sequence contains repeating aspartate-tyrosine-lysine (DYK) epitope motifs interspersed with additional charged residues (glutamate), and terminates with the FLAG octapeptide epitope (DYKDDDDK). This composition makes it valuable as a control peptide, immunogen, or detection standard in applications requiring epitope recognition, antibody development, or peptide-based protein tagging. Supplied as 10 mg of lyophilized powder.

Scientific Overview

The FLAG octapeptide epitope (DYKDDDDK) is one of the most widely used peptide tags in molecular biology. It is recognized by multiple anti-FLAG monoclonal antibodies with high specificity and is used to label and purify recombinant proteins, detect transgenes, and perform immunoaffinity chromatography. The MDYKDHDGDYKDHDIDYKDDDDK sequence contains multiple DYK motifs in tandem, which may serve as repeating epitope units or immunogenic structures in immunological assays. The presence of both charged (glutamate, aspartate) and aromatic (tyrosine) residues provides hydrophilicity and potential for multivalent antibody recognition. As a synthetic peptide, it serves as an excellent positive control, immunogen substrate, or binding standard for assay development and validation.

Key applications include:

• Positive control or calibration standard in anti-FLAG antibody assays and ELISA
• Immunogen for raising anti-FLAG or anti-epitope antibodies in rabbits, mice, or other hosts
• Standard in epitope mapping and peptide-antibody interaction studies
• Coating antigen for protein-peptide binding assays
• Quality control reference for peptide synthesis and mass spectrometry validation

Usage & Handling Guidance

Reconstitute the lyophilized powder in ultrapure water, phosphate-buffered saline (PBS), or your chosen assay buffer. The peptide is freely soluble in aqueous solutions and most common biochemical buffers. Start with a concentration suitable for your assay (for example, 1–100 μM for immunoassays). Store reconstituted solutions at 2–8°C if used within days, or at –20°C for longer storage. Avoid repeated freeze-thaw cycles by preparing aliquots.

• Solubility: Readily soluble in water and aqueous buffers at physiological pH.
• Stability: The lyophilized powder is stable for years at –20°C; once reconstituted, use within weeks (store at 2–8°C) or months (at –20°C).
• Concentration recommendations: For immunoassays, 1–10 μM; for immunization, 1–10 mg/mL in aqueous or saline buffer.
• Purity check: You can verify the peptide by mass spectrometry (expected MH+ = 2862.87 m/z) or high-performance liquid chromatography (HPLC).

What You Get

• 10 mg of lyophilized MDYKDHDGDYKDHDIDYKDDDDK peptide
• High-purity synthetic peptide (biotechnology grade)
• Molecular weight: 2861.87 Da
• Ready to reconstitute and use in immunological or binding assays
• For research use only (RUO)

Why Researchers Choose It

• Contains the widely-recognized FLAG epitope recognized by anti-FLAG monoclonal antibodies
• Repeating DYK motif design for potential multivalent antibody engagement
• High purity and well-defined chemical composition
• Suitable as immunogen, control, or assay standard
• Lyophilized format for convenient storage and long shelf-life
• Excellent positive control for validating anti-FLAG detection methods

Frequently Asked Questions (FAQ)

• What is the FLAG epitope?
  FLAG is the peptide sequence DYKDDDDK, recognized with high affinity and specificity by anti-FLAG monoclonal antibodies (e.g., M1, M2). It is widely used to tag recombinant proteins for detection and purification.
• Will anti-FLAG antibodies recognize this peptide?
  Yes. This peptide contains the complete DYKDDDDK epitope and can be used as a positive control or standard with anti-FLAG antibodies in ELISA, Western blot, immunoprecipitation, and immunofluorescence.
• Can I use this as an immunogen to generate antibodies?
  Yes. At 1–10 mg/mL in saline or PBS, the peptide is suitable for immunization of rabbits, mice, or other hosts to raise antibodies against the FLAG tag or DYK epitope.
• How should I store the lyophilized peptide?
  Keep the sealed vial at –20°C. Once reconstituted, store solutions at 2–8°C (for short-term use, up to a few weeks) or –20°C (for longer storage); avoid repeated freeze-thaw cycles.
• What is the expected mass?
  The peptide has a calculated molecular weight of 2861.87 Da. You can verify this using mass spectrometry, which should show an [M+H]+ ion at approximately 2862.87 m/z.

References

• Knappik A, Plückthun A. An improved affinity tag based on the FLAG peptide for the detection and purification of recombinant antibody fragments. Biotechniques. 1994;17(4):754-61.
• Slootstra JW, Kuperus D, Plückthun A, Meloen RH. Identification of new tag sequences with differential and selective recognition properties for the anti-FLAG monoclonal antibodies M1, M2 and M5. Mol Divers. 1997;2(3):156-64.
• Krishnan G, Morabito MA, Moczydlowski E. Expression and characterization of Flag-epitope- and hexahistidine-tagged derivatives of saxiphilin for use in detection and assay of saxitoxin. Toxicon. 2001;39(2-3):291-301.