A mild chemically cleavable linker system for functional proteomic applications.

摘要: One of the primary goals in field proteomics is finding ways to enrich specific protein targets from complex mixtures. Generally, this accomplished with activity-based probes (ABPs) that allow modification by formation a stable covalent bond reactive groups on target protein. Such proteomic often carry biotin tags and can either be generally towards free nucleophiles, such as thiols (i.e, isotope-coded affinity tagging (ICAT) reagents), or react through enzymatic process key catalytic residue. Although enrichment immobilized streptavidin allows efficient isolation even highly dilute targets, one limitations need for harsh, denaturing conditions disrupt biotin–streptavidin interaction. This elution results contamination desired probe-labeled proteins avidin monomers, were nonselectively bound streptavidin, endogenously biotinylated proteins. Hence, additional purification techniques gel electrophoresis are required prior identification MS. The incorporation cleavable linker between tag site attachment protease provides significant advance it probelabeled peptides. Recently, number linkers have been reported focus applications MS ICAT. However, these reagents require strong acid (trifluoroacetic acid), making cleavage labeled directly strepavidin resin problematic nonselective release also occur. Disulfide systems, though useful variety applications, subject disulfide exchange show premature cellular systems reducing buffer solutions. Herein, we report novel diazobenzene derivative its application chemoselective system (Scheme 1). easily incorporated into small-molecule