title: A fast, visible-light-sensitive azobenzene for bioorthogonal ligation.
abstract: Azobenzenes have been used as photoresponsive units for the control of numerous biological processes. Primary prerequisites for such applications are site-selective incorporation of photoswitchable units into biomolecules and the possibility of using non-destructive and deep-tissue-penetrating visible light for the photoisomerization. Here we report a push-pull azobenzene that readily undergoes a Staudinger-Bertozzi ligation with azide groups, that can be addressed with visible light (>440 nm) and exhibits the solvato- and acidochromism typical for push-pull systems. The thermal relaxation in aqueous environment proceeds on the low-millisecond timescale, thus enabling control over biological processes on similar timescales. The approach is demonstrated in the modification of a quartz surface and in the incorporation of an azobenzene unit into a functional peptide, the third zinc finger in the mammalian factor Sp1.
authors.affiliation: Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen (NL), Fax: (+31) 50-3634279.
authors.forename: Claudia
authors.initials: C
authors.lastname: Poloni
authors.forename: Wiktor
authors.initials: W
authors.lastname: Szymański
authors.forename: Lili
authors.initials: L
authors.lastname: Hou
authors.forename: Wesley R
authors.initials: WR
authors.lastname: Browne
authors.forename: Ben L
authors.initials: BL
authors.lastname: Feringa
mesh_terms: D001386:Azides / Q000737:chemistry; D001391:Azo Compounds / Q000737:chemistry*; D006801:Humans; D007536:Isomerism; D008027:Light; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry*; D016329:Sp1 Transcription Factor / Q000737:chemistry*; D016335:Zinc Fingers
chemical_list: D001386:Azides; D001391:Azo Compounds; D010455:Peptides; D016329:Sp1 Transcription Factor; C009850:azobenzene
keywords: DNA; azobenzenes; peptides modification; photochromism; photoisomerization