title: Comparative study on the conformation of phalloidin, viroisin, and related derivatives in aqueous solution.
abstract: We investigated the conformations of toxic phalloidin and viroisin in aqueous solution using 500-MHz 1H-NMR spectroscopy in conjunction with molecular modeling. The conformations of two non-toxic phalloidin derivatives, secophalloidin and dethiophalloidin, were also correspondingly studied for comparison purposes. Results indicate that the non-toxic peptides have a multiple conformation, whereas the toxic peptides are comprised of a rigid molecule. It was found that the conformation of phalloidin partially resembles that of viroisin in the region of Cys3-Pro4-Ala5-Trp6, being different from that of the non-toxic peptides; thereby suggesting this region plays an important role leading to their toxicity.
authors.affiliation: Institute of Applied Biochemistry, University of Tsukuba, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Kobayashi
authors.forename: S
authors.initials: S
authors.lastname: Endo
authors.forename: H
authors.initials: H
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Faulstich
authors.forename: T
authors.initials: T
authors.lastname: Wieland
authors.forename: E
authors.initials: E
authors.lastname: Munekata
mesh_terms: D000595:Amino Acid Sequence; D002244:Carbon; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000737:chemistry*; D010590:Phalloidine / Q000031:analogs & derivatives / Q000737:chemistry*; D011487:Protein Conformation; D011522:Protons; D012996:Solutions; D013329:Structure-Activity Relationship; D014867:Water
chemical_list: D010456:Peptides, Cyclic; D011522:Protons; D012996:Solutions; D014867:Water; D010590:Phalloidine; C063636:dethiophalloidin; C040703:viroisin; D002244:Carbon