This solution contains MgCl2, ATP, and ATP regenerating enzymes to recycle ATP hydrolysis products, (AMP, ADP) to ATP

Liquid. In 50 mM TRIS-Cl, pH 7.5.

An ideal energy source for conjugation/degradation assays (ubiquitin, proteasome, SUMO, etc.) particularly those that are preformed with crude lysates/impure reagents that may contain ATP-depleting activities.