K6-linked Tetra-Ubiquitin (human) (rec.) (untagged)

Recombinant Protein. Four enzymatically conjugated human ubiquitin (aa1-76) covalently linked through an isopeptide bond at K6 residue of one ubiquitin molecule and the C-terminal glycine residue of another ubiquitin molecule and untagged. Source/Host: E. coli. Liquid. In 50mM HEPES pH 7.5. The array of cellular processes initiated and regulated by ubiquitin has been partially explained by the structural diversity of differently linked ubiquitin chains. In a ubiquitin chain, ubiquitin moieties can be conjugated through one of their lysine residues (K6, K11, K27, K29, K33, K48 and K63) or the N-terminal methionine residue (M1), offering countless possibilities to assemble a specific polymer. Ubiquitin molecules can also be modified by other post-translational modifications, including acetylation and phosphorylation, adding another layer of ubiquitin signal regulation and diversification. K6-linked ubiquitin linkages are found at increased levels in response to UV radiation, indirectly associated with DNA repair, and have been identified on mitochondrial outer membrane (MOM) proteins. This protein is formed with wild-type human recombinant ubiquitin and linkage-specific enzymes. Ideal for investigating ubiquitin-binding proteins and as substrates for ubiquitin-specific isopeptidases. Reaction conditions will need to be optimized for each specific application.