Recombinant Human Di-Ub/Ub2 WT Chains (K11-linked), CF

With a predicted molecular weight of 17 kDa, Di-Ubiquitin is composed of two Ubiquitin monomers that are covalently linked through an isopeptide bond, which typically form between a lysine residue of one Ubiquitin molecule and the C-terminal glycine residue of another Ubiquitin molecule (1). Each human Ubiquitin monomer is 76 amino acids (aa) in length and shares 96% and 100% aa identity with yeast and mouse Ubiquitin, respectively (2). Ubiquitin has seven lysine residues that can participate in the formation of poly-Ubiquitin chains. The specific lysine residue used in Ubiquitin conjugation is thought to determine the function of poly-ubiquitination in cellular processes such as protein degradation, signaling, and trafficking (3-8).

Linkage specific di-Ubiquitin is a substrate for enzymes that cleave the isopeptide linkage between two Ubiquitin molecules. It can also be used to investigate mechanism of binding and recognition by Ubiquitin-activating (E1) or Ubiquitin-conjugating (E2) enzymes, deubiquitinating enzymes (DUBs), Ubiquitin ligases (E3), or other proteins that contain Ubiquitin-associated domains (UBAs) or Ubiquitin-interacting motifs (UIMs). This product is formed with wild-type Human Recombinant Ubiquitin and linkage-specific enzymes. Whereas K48-linked Ub chains mediate proteasomal degradation, and K63-linked Ub chains act in non-proteolytic events, the roles of unconventional poly-ubiquitin chains (linked through K6, K11, K27, K29, or K33) are not yet well understood. These non-canonical linkages are abundant in vivo and they may also target proteins for degradation. Ubiquitination through K11 is also important for endoplasmic reticulum-associated degradation (ERAD) and at least one DUB (OTUD7B/Cezanne) demonstrates specificity for K11 linkages. This product is synthesized with wild-type Ubiquitin.