technology overview

Our technology platform consists of three proprietary technologies, UbiQ-Block™, UbiQ-Click™ and UbiQ-Syn™, which allow us to develop unique products and services that have been lacking in the ubiquitin (Ub) field. With these chemical synthesis technologies we can construct any Ub conjugate, Ub mutant and combinations thereof. It is now possible to develop known reagents more efficiently, but foremost to construct reagents that are far beyond the reach of any currently available (biological) approach. With our proprietary technology platform we are able to fully synthesize site-selective ubiquitinated peptides of native conformation, using automated solid phase peptide synthesis:

Access to well defined ubiquitinated peptides and conjugates, which could so far not be routinely produced (bio)chemically, is of paramount importance for screening assays for the identification of new drugs, as well as for fundamental research and structural studies. Just as automated phosphopeptide synthesis has revolutionized kinase targeted research and pharmaceutical efforts alike, we believe that our technologies will have a similar impact in the field of Ub protein modification and drug discovery.


Our UbiQ-Block™ technology is a highly efficient chemical ligation approach that allows us to construct, in a site-selective and native manner, any desired Ub and/or Ub-like protein (Ubl) modified polypeptide. No alternative technique allows the parallel production of these native conjugates in a cost-effective way. Key building blocks in this technology are our proprietary gamma- and delta-thiolysine building blocks, which are readily synthesized from commercially available reagents and can be used in conventional automated Fmoc Solid Phase Peptide Synthesis. Some important applications of these Ub/Ubl modified polypeptides are:

  • as HTS assay reagents in the search for inhibitors of deubiquitinating enzymes (DUBs)
  • to perform DUB activity profiling
  • in the development of antibodies (quality control)
  • as fundamental research tools


Our UbiQ-Click™ technology enables us to synthesize well-defined and proteolytically stable Ub modified (poly)peptides. Here the native isopeptide bond is replaced by a proteolytically stable amide isostere. Because these conjugates are only modified at the isopeptide amide bond, the overall structure around the native Ub-Lysine environment is preserved to a maximal extent. These proteolytically stable conjugates can be used:

  • as inert crystallization tools
  • for immunization experiments with modified peptide antigens, leading to the selection and production of (monoclonal) antibodies with selectivity for the modified proteins/peptides vis-à-vis the unmodified variant.
  • as affinity support in mass-spectrometry based proteomics studies
  • in DUB affinity studies
  • as fundamental research tools


UbiQ-Syn™ is a newly developed highly efficient total linear solid phase peptide synthesis of the 76 amino acid Ub polypeptide sequence. It allows us to produce Ub mutants that are beyond the reach of current biological approaches. Introduction of affinity tags (e.g. His6 or HA) and/or fluorescent dyes (e.g. tetramethylrhodamine and fluorescein) is also possible. These Ub mutants can be used:

  • to study Ub-protein interactions
  • to study the E1/E2/E3 ligation machinery
  • as intermediates of special products (e.g. radioactive labelled Ub)
  • as fundamental research tools

Because our three core technologies are complementary, we have structural control on all aspects of our reagents: the Ub part, the substrate derived (poly)peptide sequence and the type of linkage between these two. For example, it is possible to use a particular Ub mutant, made by the UbiQ-Syn™ approach, in the UbiQ-Block™ or UbiQ-Click™ technology.