Recombinant Human Ubiquitin protein (Chemical Free) (FITC) (ab81668)



  • NatureRecombinant
  • SourceEscherichia coli
  • Amino Acid Sequence
    • AccessionP62988
    • SpeciesHuman
    • Additional sequence informationUbiquitin modified with fluorescein via primary amine coupling
  • ConjugationFITC. Ex: 493nm, Em: 528nm


Our Abpromise guarantee covers the use of ab81668 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

  • Applications


  • Purity> 95 % SDS-PAGE.

  • FormLyophilised
  • Additional notes

    Ubiquitin modified with fluorescein via primary amine coupling. This results in multiple fluoresceinated ubiquitin species with modified lysines as well as the N-terminus. Although having a fully functional C-terminus, lysine modification may limit the ability of this reagent to efficiently incorporate into poly-ubiquitin chains.


    Fluorescein-ubiquitin gives a strong signal in the range of 0.1-1 μM, depending on exact experimental conditions. Optimal fluorescence at pH 8.0 is monitored using Ex490 nm and Em515 nm wavelengths respectively.

  • Concentration information loading...

Preparation and Storage

  • Stability and Storage

    Shipped at 4°C. After reconstitution store at -20ºC. Avoid freeze / thaw cycles.


  • ReconstitutionSoluble in aqueous buffer or DMSO up to 20 mg/ml.

General Info

  • Alternative names
    • FLJ25987
    • MGC8385
    • Polyubiquitin B
    • RPS 27A
    • RPS27A
    • UBA 52
    • UBA 80
    • UBA52
    • UBA80
    • UBB
    • UBC
    • UBCEP 1
    • UBCEP 2
    • UBCEP1
    • UBCEP2
    • Ubiquitin
    • Ubiquitin B
    see all
  • RelevanceFunction: Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, DNA-damage responses as well as in signaling processes leading to activation of the transcription factor NF-kappa-B. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling. Similarity: Belongs to the ubiquitin family. Contains 3 ubiquitin-like domains.
  • Cellular localizationCell Membrane, Cytoplasmic and Nuclear

References for Recombinant Human Ubiquitin protein (Chemical Free) (FITC) (ab81668)

ab81668 has not yet been referenced specifically in any publications.

Product Wall

There are currently no Abreviews or Questions for ab81668.
Please use the links above to contact us or submit feedback about this product.