Removal of nonspecific binding proteins from cell and tissue extracts using 2-aminobenzimidazole-tethered affinity resin.

Cellular drug target identification through affinity chromatography is often hindered by the quantity of nonspecific binders, such as cytoskeletal and heat shock proteins. Thus, we prepared a 2-aminobenzimidazole-tethered depletion resin designed for removal of these proteins, and tested it on human lung carcinoma cell and rat tissue extracts. Column-bound proteins were identified by two-dimensional gel electrophoresis and MS. Among others, tubulins, actins and heat shock proteins were successfully depleted. Due to the reduction of these highly abundant proteins detection of potential drug targets is considerably facilitated in the pre-purified samples.