title: Chemical control of metabolically-engineered voltage-gated K+ channels.
abstract: Metabolic oligosaccharide engineering is a powerful approach for installing unnatural glycans with unique functional groups into the glycocalyx of living cells and animals. Using this approach, we showed that K(+) channel complexes decorated with thiol-containing sialic acids were irreversibly inhibited with scorpion toxins bearing a pendant maleimide group. Irreversible inhibition required a glycosylated K(+) channel subunit and was completely reversible with mild reductant when the tether connecting the toxin to the maleimide contained a disulfide bond. Cleavage of the disulfide bond not only restored function, but delivered a biotin moiety to the modified K(+) channel subunit, providing a novel approach for preferentially labeling wild type K(+) channel complexes functioning in cells.
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, Programs in Neuroscience and Chemical Biology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605-2324, USA.
authors.forename: Zhengmao
authors.initials: Z
authors.lastname: Hua
authors.forename: Anatoli
authors.initials: A
authors.lastname: Lvov
authors.forename: Trevor J
authors.initials: TJ
authors.lastname: Morin
authors.forename: William R
authors.initials: WR
authors.lastname: Kobertz
mesh_terms: D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D015640:Ion Channel Gating; D015221:Potassium Channels / Q000737:chemistry* / Q000378:metabolism
chemical_list: D015221:Potassium Channels