(E3-independent) E2 ubiquitin-conjugating enzyme

The enzyme transfers a single ubiquitin directly from an ubiquitinated E1 ubiquitin-activating enzyme to itself, and on to a lysine residue of the acceptor protein without involvement of E3 ubiquitin transferases (cf. EC 2.3.2.26, EC 2.3.2.27). It forms a labile ubiquitin adduct in the presence of E1, ubiquitin, and Mg2+-ATP and catalyses the conjugation of ubiquitin to protein substrates, independently of E3. This transfer has only been observed with small proteins. In vitro a transfer to small acceptors (e.g. L-lysine, N-acetyl-L-lysine methyl ester) has been observed.

• Supplier: Creative Enzymes
• Product #: EXWM-2298