Spot-Tag Cloning Vectors

Create Your Own Spot-Tag Protein

These 12 amino acids will make all the difference

The Spot-Tag Fusion Protein System is the first "create-your-own" peptide-tag specifically designed for use with the “nanobody” suite of products. Nanobodies are small, high-performance fragments of monoclonal antibodies that show superior performance across a wide range of detection, purification, and imaging applications. This connection allows any lab to easily construct and express a single Spot-Tag fusion protein, which can then be used with any of our capture or detection applications. For example, the Spot-Trap Affinity Reagents can be used to purify any Spot-Tagged protein in a single step, whether by a simple immunoprecipitation or by ultrapure affinity purification – even under gentle conditions that preserve protein function. The same Spot-Tagged protein can also be detected with the tiny and rugged Spot-Label, which will specifically bind for ultra-sensitive Western Blotting and ultra-bright immunofluorescence (or even super-resolution microscopy).



See Below for Data Sheets
Spot-Trap Affinity Reagents
Nanobody-Trap Reagents
Live Cell Imaging Systems


Spot-Tag Fusion Protein Uses


The Spot-Tag system is fully validated! The Spot-Tag sequence is: PDRVRAVSHWSS. It’s just 1.4kDa, and can easily be placed at either the C-terminus or the N-terminus without impacting your target protein’s function. In practical experiments, it has proven to be completely inert, easy to clone, and to express at good levels in bacteria, yeast, mammalian, and insect cell lines. The Spot-Nanobody’s sequence and structure are known as well; its binding mechanism with Spot-Tag has been elucidated. Spot-Nanobody is produced recombinantly for consistently high quality. Precise production guarantees performance no matter the configuration: affinity purification (Spot-Trap), immunoprecipitation (Spot-Trap), Westerns (Spot-Label monovalent form), and immunofluorescence (Spot-Label divalent form) are all possible.


Spot advantages compared to Flag

More robust & stable

Higher affinity

Less background

Higher resolution

Less negatively charged

Shorter than other tags

Less nonspecific binding



N-terminus and C-terminus

Codon optimized sequences for Spot-Tag:



Optional Linker

We recommend a short Gly-Ser linker, if there are adjacent acidic amino acids (Glu/Asp):

E. coli: GGTTCT

S. cerevisiae: GGTTCT

Human cell line: GGCAGC


Spot vectors for cloning

Vector Data- sheet Sequence file
pSpot1 vector, E. coli, Spot-tag N-term., Kan., high expression ev-1.pdf
pSpot2 vector,  E. coli, Spot-tag C-term., Kan., high expression ev-2.pdf
pSpot3 vector, E. coli, Spot-tag C-term., Amp., low expression ev-3.pdf
pSpot4 vector,  E. coli, Spot-tag N-term., Amp., low expression ev-4.pdf
pSpot5 vector, S. cerevisiae, Spot-tag N-term., Leu, CEN, low expression ev-5.pdf
pSpot6 vector, S. cerevisiae, Spot-tag C-term., Leu, CEN, low expression ev-6.pdf
pSpot7 vector, S. cerevisiae, Spot-tag N-term., Leu, 2µ, high expression ev-7.pdf
pSpot8 vector, S. cerevisiae, Spot-tag C-term., Leu, 2µ, high expression ev-8.pdf




DNA Plasmid


1.25 µg

Expression Level: High and low expression plasmids available
Resistance: Kan, Amp, & Leu avaiable
Spot-Tag Amini Acid Sequence: PDRVRAVSHWSS

Part Numbers

pSpot1, pSpot2, pSpot3, pSpot4, pSpot5, pSpot6, pSpot7, pSpot8, EP1


store at -20°C

Spot-Tag Vectors

ORDERING - Spot-Tag Vectors



Spot Peptide

ORDERING - Spot peptide