Effect of the D-Phe2 residue on molecular conformation of an endogenous neuropeptide achatin-I. Comparison of X-ray crystal structures of achatin-I (H-Gly-D-Phe-Ala-Asp-OH) and achatin-II (H-Gly-Phe-Ala-Asp-OH).
The molecular conformation of achatin-II neutral form (H-Gly-Phe-Ala-Asp-OH), an endogenous peptide from the Achatina fulica ganglia, was elucidated by X-ray crystal analysis. The molecule takes an extended beta-pleated structure stabilized by 5 intermolecular hydrogen bonds with the antiparallely arranged molecules. This is in contrast with the turn conformation of a neuroactive achatin-I (H-Gly-D-Phe-Ala-Asp-OH) [(1992) FEBS Lett. 276,95-97]. The conformational comparison of both of the molecules makes clear the structural role which D-Phe residue of achatin-I plays in forming a definite active form.
Ishida
T
T
Department of Physical Chemistry, Osaka University of Pharmaceutical Sciences, Japan.
In
Y
Y
Inoue
M
M
Yasuda-Kamatani
Y
Y
Minakata
H
H
Iwashita
T
T
Nomoto
K
K
D000595:Amino Acid Sequence; D007447:Invertebrate Hormones / Q000737:chemistry*; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000737:chemistry*; D010649:Phenylalanine / Q000737:chemistry*; D011487:Protein Conformation; D014961:X-Ray Diffraction
D007447:Invertebrate Hormones; D009479:Neuropeptides; C059927:achatin I; D010649:Phenylalanine