title: Deeply inverted electron-hole recombination in a luminescent antibody-stilbene complex.
abstract: The blue-emissive antibody EP2-19G2 that has been elicited against trans-stilbene has unprecedented ability to produce bright luminescence and has been used as a biosensor in various applications. We show that the prolonged luminescence is not stilbene fluorescence. Instead, the emissive species is a charge-transfer excited complex of an anionic stilbene and a cationic, parallel pi-stacked tryptophan. Upon charge recombination, this complex generates exceptionally bright blue light. Complex formation is enabled by a deeply penetrating ligand-binding pocket, which in turn results from a noncanonical interface between the two variable domains of the antibody.
authors.affiliation: Department of Molecular Biology, Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Erik W
authors.initials: EW
authors.lastname: Debler
authors.forename: Gunnar F
authors.initials: GF
authors.lastname: Kaufmann
authors.forename: Michael M
authors.initials: MM
authors.lastname: Meijler
authors.forename: Andreas
authors.initials: A
authors.lastname: Heine
authors.forename: Jenny M
authors.initials: JM
authors.lastname: Mee
authors.forename: Goran
authors.initials: G
authors.lastname: Pljevaljcic
authors.forename: Angel J
authors.initials: AJ
authors.lastname: Di Bilio
authors.forename: Peter G
authors.initials: PG
authors.lastname: Schultz
authors.forename: David P
authors.initials: DP
authors.lastname: Millar
authors.forename: Kim D
authors.initials: KD
authors.lastname: Janda
authors.forename: Ian A
authors.initials: IA
authors.lastname: Wilson
authors.forename: Harry B
authors.initials: HB
authors.lastname: Gray
authors.forename: Richard A
authors.initials: RA
authors.lastname: Lerner
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D000936:Antigen-Antibody Complex; D001666:Binding Sites, Antibody; D003460:Crystallization; D018360:Crystallography, X-Ray; D004583:Electrons; D005453:Fluorescence; D005454:Fluorescence Polarization; D006241:Haptens / Q000737:chemistry / Q000276:immunology; D057927:Hydrophobic and Hydrophilic Interactions; D007135:Immunoglobulin Variable Region / Q000737:chemistry* / Q000276:immunology; D008024:Ligands; D049449:Luminescence; D009154:Mutation; D010084:Oxidation-Reduction; D017434:Protein Structure, Tertiary; D013050:Spectrometry, Fluorescence; D013057:Spectrum Analysis; D013267:Stilbenes / Q000737:chemistry* / Q000276:immunology; D014364:Tryptophan / Q000737:chemistry
chemical_list: D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D006241:Haptens; D007135:Immunoglobulin Variable Region; D008024:Ligands; D013267:Stilbenes; D014364:Tryptophan