The Tag:GS-TAP sequence is a multiple component tag designed for tandem affinity purification and consists of two IgG binding domains of S.aureus protein G, one or two TEV protease cleavage sites and the streptavidin binding peptide Tag:SBP (PMID:17060908). When fused to the N- or C-terminal end of a protein of interest, a tandem affinity purification tag allows for rapid purification under native conditions of complexes, even when expressed at their natural level. Prior knowledge of complex composition or function is not required (PMID:11403571). Compared to the conventional Tag:TAP purification tag, 10-fold improvements in yield have been reported with Tag:GS-TAP (PMID:17060908), resulting from significantly lower levels of contaminating proteins, and a higher yield of bait protein (FBrf0210465).