title: pH-Dependent structural change in neoculin with special reference to its taste-modifying activity.
abstract: Neoculin has pH-dependent taste-modifying activity. This study found that neoculin changed pH-dependently in its tryptophan- and ANS-derived fluorescence spectra, while no such change occurred in a neoculin variant whose histidine residues were replaced with alanine. These results suggest that the sweetness of neoculin depends on structural change accompanying the pH change, with the histidine residues playing a key role.
authors.affiliation: Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Morita
authors.forename: Ken-ichiro
authors.initials: K
authors.lastname: Nakajima
authors.forename: Kisho
authors.initials: K
authors.lastname: Iizuka
authors.forename: Tohru
authors.initials: T
authors.lastname: Terada
authors.forename: Akiko
authors.initials: A
authors.lastname: Shimizu-Ibuka
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ito
authors.forename: Ayako
authors.initials: A
authors.lastname: Koizumi
authors.forename: Tomiko
authors.initials: T
authors.lastname: Asakura
authors.forename: Takumi
authors.initials: T
authors.lastname: Misaka
authors.forename: Keiko
authors.initials: K
authors.lastname: Abe
mesh_terms: D006801:Humans; D006863:Hydrogen-Ion Concentration; D010940:Plant Proteins / Q000737:chemistry* / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013649:Taste / Q000187:drug effects* / Q000502:physiology; D014364:Tryptophan
chemical_list: D010940:Plant Proteins; C511659:neoculin protein, Curculigo latifolia; D014364:Tryptophan