title: Near-Quantitative Aqueous Synthesis of Rotaxanes via Bioconjugation to Oligopeptides and Proteins.
abstract: In spite of widespread interest in rotaxane-based molecular machines and materials, rotaxanes have not been attached covalently to proteins. We describe the near-quantitative aqueous synthesis of [2]rotaxanes based on neutral and charged aqueous hosts-cucurbit[7]uril (CB7) and cyclobis(paraquat-p-phenylene) (CBPQT4+), respectively-using the thiol-ene addition of cysteine and maleimide as a stoppering protocol. After verifying the high efficiency of the reaction using glutathione (GSH) as an oligopeptide stopper, we have employed cytochrome C (CytC) as a protein stopper to produce the first well-characterized protein-rotaxane bioconjugates. We anticipate that this methodology will enable the preparation of novel materials that combine the unique properties of proteins and mechanical bonds.
authors.forename: Carson J
authors.initials: CJ
authors.lastname: Bruns
authors.forename: Hanwei
authors.initials: H
authors.lastname: Liu
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Francis
mesh_terms: D045304:Cytochromes c / Q000737:chemistry* / Q000378:metabolism; D005978:Glutathione / Q000737:chemistry*; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism; D043862:Rotaxanes / Q000138:chemical synthesis* / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D009842:Oligopeptides; D043862:Rotaxanes; D014867:Water; D045304:Cytochromes c; D005978:Glutathione