[(Nε-biotinyl)Lys6, (Nε-biotinyl)Lys63]Ubiquitin Product Specification Formulation: Liquid. In TRIS/HCl, pH 7.6. Application: Specifically biotinylated ubiquitin is useful for studying ubiquitinylation in vitro, and for detection and purification of ubiquitylated substrates. This biotinylated ubiquitin species is activated by E1 and is a competent substrate for E2 and E3 enzymes. Long Term Storage: -20°C