Stock solution of buffer used for assaying ubiquitin enzymes.

• Buffer passed through a 0.2 µm filter membrane and packaged aseptically
• Frozen solution of buffer containing: 50 mM HEPES, pH 7.5, 100 mM NaCl, 50 µg/ml BSA, 3 mM MgCl₂
• Store at −20 °C

For optimal storage, aliquot buffer into smaller quantities after centrifugation and store at recommended temperature. For most favorable performance, avoid repeated handling and multiple freeze/thaw cycles.