title: "Superchiral" Spectroscopy: Detection of Protein Higher Order Hierarchical Structure with Chiral Plasmonic Nanostructures.
abstract: Optical spectroscopic methods do not routinely provide information on higher order hierarchical structure (tertiary/quaternary) of biological macromolecules and assemblies. This necessitates the use of time-consuming and material intensive techniques, such as protein crystallography, NMR, and electron microscopy. Here we demonstrate a spectroscopic phenomenon, superchiral polarimetry, which can rapidly characterize ligand-induced changes in protein higher order (tertiary/quaternary) structure at the picogram level, which is undetectable using conventional CD spectroscopy. This is achieved by utilizing the enhanced sensitivity of superchiral evanescent fields to mesoscale chiral structure.
authors.forename: Ryan
authors.initials: R
authors.lastname: Tullius
authors.forename: Affar S
authors.initials: AS
authors.lastname: Karimullah
authors.forename: Marion
authors.initials: M
authors.lastname: Rodier
authors.forename: Brian
authors.initials: B
authors.lastname: Fitzpatrick
authors.forename: Nikolaj
authors.initials: N
authors.lastname: Gadegaard
authors.forename: Laurence D
authors.initials: LD
authors.lastname: Barron
authors.affiliation: §Department of Chemistry, University of Massachusetts Amherst, Massachusetts 01003, United States.
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Rotello
authors.forename: Graeme
authors.initials: G
authors.lastname: Cooke
authors.forename: Adrian
authors.initials: A
authors.lastname: Lapthorn
authors.forename: Malcolm
authors.initials: M
authors.lastname: Kadodwala
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase / Q000737:chemistry; D002021:Buffers; D002942:Circular Dichroism; D016974:Dickeya chrysanthemi / Q000201:enzymology; D004926:Escherichia coli / Q000201:enzymology; D008024:Ligands; D046911:Macromolecular Substances; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000737:chemistry; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods*; D013237:Stereoisomerism
chemical_list: D002021:Buffers; D008024:Ligands; D046911:Macromolecular Substances; D011506:Proteins; D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D017853:Phosphotransferases (Alcohol Group Acceptor); C022642:shikimate kinase