TAP tags contain:
Tandem Affinity Purification tag is a bipartite fusion construct designed for sequential affinity capture and high-purity complex isolation under native conditions. It traditionally comprises two IgG-binding domains of Protein A from Staphylococcus aureus separated by a TEV protease cleavage site from Calmodulin Binding Peptide. First affinity utilizes Protein A binding to IgG matrix, then TEV cleavage releases complex, followed by second capture on calmodulin resin in presence of calcium. It does not contain DNA probes, RNA tags, or fluorescent proteins, which serve different purposes in dete
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.