title: Development of bifunctional photoactivatable benzophenone probes and their application to glycoside substrates.
abstract: Photoaffinity labeling is used to covalently attach ligands to macromolecules to determine their spatial arrangement and structure. Benzophenone (BP) groups are widely used for covalent photoaffinity labeling and for probing protein interactions. We developed bifunctional BP photoactivatable derivatives using three different general chemical approaches. In addition to the photoaffinity reactivity of the BP, these derivatives contain an additional group: A radioactive tracer for biological studies, or an N-ethylmaleimide group as an additional crosslinker, or a biotin group to be used during purification and characterization of probe-protein complexes using the high-affinity biotin-avidin interaction. A model series of photoaffinity labeling probes was synthesized based on the arbutin ligand. These compounds can be used as probes to study the arbutin binding site of microbial beta-glucoside transporters by photolabeling residues in its vicinity. The second functionality provides additional options for studying proteins and binding sites. The probes were developed using different methodologies: (i) a diazotation reaction; (ii) protecting group methodology; and (iii) solid-phase synthesis. These procedures are general and provide a simple and versatile approach for synthesizing bifunctional BP ligands, as demonstrated here on arbutin.
authors.affiliation: Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel. nir.qvit@gmail.com
authors.forename: Nir
authors.initials: N
authors.lastname: Qvit
authors.forename: Galya
authors.initials: G
authors.lastname: Monderer-Rothkoff
authors.forename: Ayelet
authors.initials: A
authors.lastname: Ido
authors.forename: Deborah E
authors.initials: DE
authors.lastname: Shalev
authors.forename: Orna
authors.initials: O
authors.lastname: Amster-Choder
authors.forename: Chaim
authors.initials: C
authors.lastname: Gilon
mesh_terms: D001577:Benzophenones / Q000138:chemical synthesis* / Q000737:chemistry; D001710:Biotin / Q000138:chemical synthesis / Q000737:chemistry; D005033:Ethylmaleimide / Q000138:chemical synthesis / Q000737:chemistry; D006027:Glycosides / Q000378:metabolism*; D015335:Molecular Probes / Q000138:chemical synthesis* / Q000737:chemistry; D019920:Photoaffinity Labels / Q000138:chemical synthesis* / Q000737:chemistry; D010777:Photochemistry / Q000379:methods*; D011714:Pyrans / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D001577:Benzophenones; D006027:Glycosides; D015335:Molecular Probes; D019920:Photoaffinity Labels; D011714:Pyrans; D001710:Biotin; C047723:benzophenone; D005033:Ethylmaleimide