Avi-tag and Amine-Labeled Biotinylated Proteins

Avi-tag and chemically labeled biotinylated proteins

NEW Avi-tag Spike and ACE-2 Proteins for SARS-CoV-2 Research. Interested in more proteins for COVID-19 research? Visit our Recombinant Proteins for Coronavirus Research page.

R&D Systems offers a wide assortment of biotinylated proteins allowing researchers to take the guesswork out of protein biotinylation. In addition to amine-labeled biotinylated proteins, we have a growing list of Avi-tag biotinylated proteins. Each biotinylated protein is held to the same industry-leading quality standards as their unlabeled counterpart while also limiting batch-to-batch variability. Also, the R&D Systems Custom Protein Development Team can work with you to create a customized protein solution to meet your specific research needs.

Advantages of Avi-tag Biotinylated
Recombinant Proteins

  • 1. Consistent labeling. Biotinylation only occurs on the single lysine residue in the Avi-tag.
  • 2. Uniform orientation of protein. When bound to a streptavidin-coated surface, the avitagged protein orientation will be uniform due to the precise control over biotinylation.
  • 3. Equivalent bioactivity. Because biotinylation is restricted to the Avi-tag, the rest of the protein is unchanged so there is no interference in the protein’s bioactivity.
  • 4. Lot-to-lot consistency. Each new lot is tested side-by-side with previous lots and with a master lot to ensure high lot-to-lot consistency.

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Avi-tag biotinylated recombinant protein binding to streptavidin-coated surface

Avi-tag Biotinylated Proteins – Products by Molecule

2B4/CD244/SLAMF4 4-1BB/TNFRSF9 5'-Nucleotidase/CD73 5T4 ACE-2 ALCAM/CD166 
Axl B7-1/CD80 B7-2/CD86 B7-H2 B7-H3 B7-H4
B7-H6 BCMA BTN1A1/Butyrophilin BTN2A1 BTN3A2 CD3 delta
CD4 CD6 CD8 alpha CD19 CD24 CD25/IL-2 R
CD27 CD28 CD30/TNFRSF8 CD38 CD40/TNFRSF5 CD44v5
CD47 CD48/SLAMF2 CD117/c-kit CD155/PVR CD200 CD200 R1
CEACAM-1/CD66a CEACAM-5/CD66e CEACAM-6/CD66c Common gamma chain CTLA-4 CX3CL1/Fractalkine
CRACC/SLAMF7 DLL4 DNAM-1/CD226 DPPIV/CD26  EGFR EpCAM/TROP1
ErbB2/Her2 ErbB3/Her3 Fc epsilon RI alpha Fc gamma RIIB/CD32b Fc gamma RIIA/CD32a Fc gamma RIIIA
FGFR1 alpha (IIIc) FGFR2 alpha (IIIc) FGFR3  FGFR4 Flt-3/Flk-2 GITR/TNFRSF18
Glypican-3 gp130 Guanylyl Cyclase C Hepassocin/FGL1 HVEM/TNFRSF14 ICAM-1/CD54
ICOS IFN-gamma R1/CD119 IgG1 IL-1 RAcP/IL-1 R3  IL-1 Rrp2/IL-1R6  IL-2 R beta
IL-3R alpha  IL-4 R alpha IL-5R alpha/CD125 IL-6 R alpha IL-7 R alpha/CD127 IL-10 R alpha
IL-12 R beta 1 IL-12 R beta 2 IL-13 R alpha 1 IL-15 R alpha IL-17RA/IL-17R IL-18 Bpa
IL-18 R alpha/IL-1 R5 IL-18 R beta/IL-1 R7 IL-21 R IL-23R  IL-31RA Jagged 1
LAG-3 LAIR1 LAIR2 LILRB2/CD85d/ILT4 Lymphotoxin alpha1/beta2 M-CSF R/CD115
Mer Mesothelin MICA MSPR/Ron MUC-1 MuSK
Nectin-1 Nectin-2/CD112 Nectin-4 Neuropilin-1 NKp30  NKp44/NCR2
Osteoactivin/GPNMB  OX40/TNFRSF4 PD-1 PD-L1/B7-H1 PD-L2/B7-DC PDGF R alpha
PDGF R beta PILR-alpha PILR-beta PSMA/FOLH1/NAALADase I ROR1 Siglec-2/CD22
Siglec-3/CD33 Siglec-10 SIRP alpha/CD172a SARS-CoV-2 Spike SARS-CoV-2 Spike RBD SARS-CoV-2 Spike S1
ST2/IL-33 R Syndecan-1/CD138 TGF-beta 1 TGF-beta RI TGF-beta RII Tie-2
TIGIT (T103) TIM-1/KIM-1/ HAVCR TIM-3 TNF-alpha TNF RI/TNFRSF1A TNF RII/TNFRSF1B
TRANCE/RANK L TREM-1  TREM2 TSLP R uPAR ULBP-2
VEGF 165 VEGFR2/KDR/ Flk-1 VEGFR3/Flt-4 VISTA/B7-H5/PD-1H VSIG3 VSIG4
VSTM2A VSTM2B        

Browse All Avi-tag Proteins

Advantages of Amine-labeled and Sugar-labeled Biotinylated Proteins

  • 1. High signal strength. Proteins typically average multiple biotins per molecule making them an excellent choice when high signal strength is important.
  • 2. Equivalent bioactivity. Biotinylated proteins are rigorously tested to ensure that they exhibit the same level of bioactivity as the unlabeled protein.
  • 3. Lot-to-lot consistency. Each new lot is tested side-by-side with previous lots and with a master lot to ensure high lot-to-lot consistency.

Amine-labeled and Sugar-labeled Biotinylated Proteins – Products by Molecule

ACE-2 AGE-BSA  Angiopoietin-1 Angiopoietin-2 Angiopoietin-like 3, N-term Angiopoietin-like 4
Angiopoietin-like 7 B7-H3 B7-H6 B7-H7 BMP-7 Dkk-1
Ephrin-A1 Ephrin-A2 Ephrin-A3 Ephrin-A4 Ephrin-A5 Ephrin-B1
Ephrin-B2 Ephrin-B3 Frizzled-8 HGF  ICOS IL-2
IL-6 IL-17A IL-17A/F Heterodimer IL-21 IL-27 LAG-3
LIF LILRB2/CD85d/ILT4 BT2078 M-CSF PD-1 PD-L1 PD-L2
PDGF-BB R-Spondin 1 SIRP-alpha SARS-CoV-2 Spike Protein  SARS-CoV-2 Spike RBD SCF/c-kit 
TGF-beta 1 TNF-alpha Ubiquitin VEGF Viral B8R Viral B18R
VISTA VSIG3 Wnt-3a Wnt-5a    

Custom Protein Services

Biotinylated protein features:

Equivalent Bioactivity

Consistent bioactivity between biotinylated and non-biotinylated proteins

Both Biotinylated Recombinant Human PD-L1/B7-H1 Fc Avi-tag and unlabeled Recombinant Human PD-L1/B7-H1 inhibit anti-CD3 antibody-induced IL-2 secretion in human T lymphocytes
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Both Biotinylated Recombinant Human VEGF 165 and unlabeled Recombinant Human VEGF 165 stimulate HUVEC human umbilical vein endothelial cell proliferation
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Both Biotinylated Recombinant Human TNF-alpha and unlabeled Recombinant Human TNF-alpha promotes cytotoxicity in L‑929 mouse fibroblast cells in the presence of the metabolic inhibitor actinomycin D
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Both Biotinylated Recombinant Human PD-L1/B7-H1 Fc Avi-tag and unlabeled Recombinant Human PD-L1/B7-H1 inhibit anti-CD3 antibody-induced IL-2 secretion in human T lymphocytes. The similarity in activity highlights that the biotinylated Avi-tag protein is fully functional. Both Biotinylated Recombinant Human VEGF 165 (Catalog # BT293) and unlabeled Recombinant Human VEGF 165 (Catalog # 293-VE) stimulate HUVEC human umbilical vein endothelial cell proliferation. The ED50 for this effect is 1-6 ng/mL. The similarity in activity highlights that the biotinylated protein is fully functional. Both Biotinylated Recombinant Human TNF-alpha (Catalog # BT210) and unlabeled Recombinant Human TNF-alpha (Catalog # 210-TA) promotes cytotoxicity in L‑929 mouse fibroblast cells in the presence of the metabolic inhibitor actinomycin D. The ED50 for this effect is 25-100 pg/mL. The similarity in activity highlights that the biotinylated protein is fully functional.

Binding activity

When 500 ng/mL of Biotinylated Recombinant Human PD-1 His-tag Avi-tag protein is immobilized onto Streptavidin coated plate, it binds to Recombinant Human PD-L1/B7-H1 Fc Chimera with an ED50 of 1.2-7.2 ng/mL
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When Recombinant Human APRIL/TNFSF13 is immobilized at 0.1 µg/mL, Recombinant Human BCMA/TNFRSF17 Fc Chimera Avi-tag binds with an ED50 of 0.3-1.8 ng/m
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When Recombinant Human VSIG3 Fc Chimera is coated at 5 μg/mL, Biotinylated Recombinant Human VISTA/B7-H5/PD-1H Fc Chimera Avi-tag binds with an ED50 of 0.5-3 μg/mL.
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When 500 ng/mL of Biotinylated Recombinant Human PD-1 His-tag Avi-tag protein is immobilized onto Streptavidin coated plate (Catalog # CP004), it binds to Recombinant Human PD-L1/B7-H1 Fc Chimera (Catalog # 156-B7) with an ED50 of 1.2-7.2 ng/mL. When Recombinant Human APRIL/TNFSF13 (Catalog # 5860-AP) is immobilized at 0.1 µg/mL, Recombinant Human BCMA/TNFRSF17 Fc Chimera Avi-tag (Catalog # AVI193) binds with an ED50 of 0.3-1.8 ng/mL. When Recombinant Human VSIG3 Fc Chimera (Catalog # 9229-VS) is coated at 5 μg/mL, Biotinylated Recombinant Human VISTA/B7-H5/PD-1H Fc Chimera Avi-tag (Catalog # AVI7126) binds with an ED50 of 0.5-3 μg/mL.

Lot-to-lot consistency

When Recombinant Human PD-1 (Catalog #1086-PD) is coated at1 μg/mL, Biotinylated Recombinant Human PD-L1/B7-H1 Avi-tag (Catalog # AVI156) binds with an ED50 of 8-48 ng/mL.
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Three independent lots of B7-H1/PD-L1 have near identical bioactivity. When Recombinant Human PD-1 (Catalog #1086-PD) is coated at1 μg/mL, Biotinylated Recombinant Human PD-L1/B7-H1 Avi-tag (Catalog # AVI156) binds with an ED50 of 8-48 ng/mL.

Surface Plasmon Resonance (SPR)

BCD155/PVR-Fc Avi-tag protein
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Immobilized CD155/PVR-Fc Avi-tag (Catalog # AVI9174) bound to streptavidin CM5 chip binds to TIGIT-Fc (Catalog # 7898-TGB) with an affinity constant of 25.4 nM. Experiment performed on Biacore T200, GE Healthcare. For more information on using Avi-tag proteins in SPR, download the application note.

About Biotinylated Proteins

Biotinylated proteins are powerful tools used in a wide variety of assay formats, including immunoprecipitation, flow cytometry, immunoassays, biopanning, and surface plasmon resonance. Historically, individual labs have made their own biotinylated proteins in small batches. However, often times researchers encounter protein-specific technical challenges and high variability leading to inconsistent results.

What is Avi-tag?

Avi-tag Biotinylated Proteins are proteins that feature biotinylation at a single site contained within the Avi-tag, a unique 15 amino acid peptide. The DNA sequence coding for the Avi-tag is inserted during cloning and contained in the final expression vector construct. Biotinylation of the Avi-tag is enzymatically added by the E. coli biotin ligase BirA. This results in a single biotin molecule covalently attached to the lysine residue within the Avi-tag. The Avi-tag sequence is Gly-Leu-Asn-Asp-Ile-Phe-Glu-Ala-Gln-Lys-Ile-Glu-Trp-His-Glu.

Other biotinylated recombinant protein resources:

All proteins from R&D Systems

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