TUBE 2 (Fluorescein)

Based on protein domains known to possess an affinity for ubiquitin, Tandem Ubiquitin Binding Entities (TUBEs) have been developed for the isolation and identification of ubiquitylated proteins. TUBEs display up to a 1000-fold increase in affinity for poly-ubiquitin moieties over the single ubiquitin binding associated domain (UBA). In addition, TUBEs display a protective effect on polyubiquitylated proteins, allowing for detection at relatively low abundance. These properties effectively “capture” protein in its polyubiquitin state. FLR-TUBE2 has an average of three fluorescein moieties (Exc. = 490 nm, Emm. = 520 nm) attached to the fusion tag of His6-TUBE2 (Cat. No. UM202). Since the fluorophore is attached to the tag, it does not affect binding of the tandem ubiquitin binding domains to polyubiquitin chains.