A1S9 Protein
Ubiquitin-protein ligase

Liquid. In 150 mM NaCl, 75 mM Tris-HCl, 5 mM DTT, 20% glycerol, pH 8.0. AVOID FREEZE/THAW CYCLES. Recombinant, human ubiquitin-activating enzyme E1 fused at the N-terminus to GST and expressed in S. frugiperda insect cells. The ubiquitin-activating enzyme, E1, is required for initiating a multi-step pathway for the covalent linkage of ubiquitin to target proteins. It is responsible for the first step in the ubiquitin-protein isopeptide bond formation by catalyzing the activation of the C-terminal carboxyl group of ubiquitin, forming a high-energy thioester bond in an ATP-dependent manner. It is a critical component for the initiation of conjugation reactions in vitro. Also available as a non-fusion protein under Cat. No. 662072. Purity: ≥98% by SDS-PAGE.

Ref.: Ciechanover, A., et al. 1982. J. Biol. Chem. 257, 2537. Haas, A.L., and Rose, I.A. 1982. J. Biol. Chem. 257, 10329. Ciechanover, A., 1981. Proc. Natl. Acad. Sci. USA 78, 761.