Fluorescein-Ubiquitin (6-FAM-Ub), human recombinant

Catalog number: SBB-TR0016, 50 μg

Highly purified recombinant protein, which has been labeled with a single fluorescein (6-FAM) moiety at a specific site that keeps all lysines within the protein available and has a functional C-terminus.  Allows for conjugation into ubiquitin chains and does not affect or impair the E1 – E2 and E3 conjugation cascade. 6-FAM Ubiquitin has an excitation maximum Ex494nm and an emission maximum Em520nm.This protein was expressed in E.coli.[1][2][3]

In stock


Ubiquitin is a highly conserved protein that plays a major role in the ubiquitylation pathway, which is conserved from yeast to mammals. Ubiquitylation, the conjugation of ubiquitin to other proteins through a covalent bond between its C-terminal glycine and the ε-amino group of lysine residues or the α-amino group of an N- terminal methionine) onto proteins is essential for many cellular process primarily linked to protein degradation. This process involves three steps with specific groups of enzymes in an ATP depended manner, which are activation with ubiquitin-activating enzymes (E1s), conjugation with ubiquitin-conjugating enzymes (E2s), and ligation with ubiquitin ligases (E3s).

For Research Use Only, Not For Use In Humans.


Product Overview
Quantity: 50 μg
Molecular Weight: 9.1 kDa
Purity: >98% by LCMS
Readout: Endpoint / Kinetic
Label or Dye: Fluorescein, 6-FAM, C21H12O7
Detection Method: Fluorescence
Substrate Properties: Protein-Based TR-FRET Pair Acceptor. Typical working concentrations range from 250 to 500 nM. However, the best working concentration needs to be empirically determined by the type of application by the end user.
Excitation/Emission (nm): 494/520
Storage Buffer: 50 mM HEPES, pH 7.5, 50 mM NaCl
Storage Store at −80°C after product arrival. Avoid multiple freeze / thaws. It is recommended to make multiple aliquots after the first thaw.

Figures & Data

Mass Spectrometry

Figure 1. LCMS. Analysis of 6-FAM Ubiquitin using LCMS intact mass determination indicates purity greater than 95%, and a molecular weight of 9,155 daltons.

Citations & References

1) Hemmilä, Ilkka and Stuart Webb. "Time-Resolved Fluorometry: An Overview Of The Labels And Core Technologies For Drug Screening Applications". N.p., 2017. Print.

2) Komander, David and Michael Rape. "The Ubiquitin Code". Annual Review of Biochemistry 81.1 (2012): 203-229. Web. 9 Mar. 2017.

3) Visser, A. J. W. G. et al. "Time-Resolved FRET Fluorescence Spectroscopy Of Visible Fluorescent Protein Pairs". European Biophysics Journal 39.2 (2009): 241-253. Web. 13 Mar. 2017.