Comparative study on the conformation of phalloidin, viroisin, and related derivatives in aqueous solution.
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.
Kobayashi
N
N
Institute of Applied Biochemistry, University of Tsukuba, Japan.
Endo
S
S
Kobayashi
H
H
Faulstich
H
H
Wieland
T
T
Munekata
E
E
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
D010456:Peptides, Cyclic; D011522:Protons; D012996:Solutions; D014867:Water; D010590:Phalloidine; C063636:dethiophalloidin; C040703:viroisin; D002244:Carbon