title: Adapter reagents for protein site specific dye labeling.
abstract: Chemoselective protein labeling remains a significant challenge in chemical biology. Although many selective labeling chemistries have been reported, the practicalities of matching the reaction with appropriately functionalized proteins and labeling reagents is often a challenge. For example, we encountered the challenge of site specifically labeling the cellular form of the murine Prion protein with a fluorescent dye. To facilitate this labeling, a protein was expressed with site specific p-acetylphenylalanine. However, the utility of this acetophenone reactive group is hampered by the severe lack of commercially available aminooxy fluorophores. Here we outline a general strategy for the efficient solid phase synthesis of adapter reagents capable of converting maleimido-labels into aminooxy or azide functional groups that can be further tuned for desired length or solubility properties. The utility of the adapter strategy is demonstrated in the context of fluorescent labeling of the murine Prion protein through an adapted aminooxy-Alexa dye.
authors.affiliation: Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, 92037.
authors.forename: Darren A
authors.initials: DA
authors.lastname: Thompson
authors.forename: Eric G B
authors.initials: EG
authors.lastname: Evans
authors.forename: Tomas
authors.initials: T
authors.lastname: Kasza
authors.forename: Glenn L
authors.initials: GL
authors.lastname: Millhauser
authors.forename: Philip E
authors.initials: PE
authors.lastname: Dawson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D004396:Coloring Agents / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D007202:Indicators and Reagents; D051379:Mice; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry; D011328:Prions / Q000378:metabolism*; D013194:Staining and Labeling
chemical_list: D004396:Coloring Agents; D007202:Indicators and Reagents; D010455:Peptides; D011328:Prions
keywords: bioconjugation; chemoselective; ketoxime