A second polymorph of a helical decapeptide.
A crystal-state structural analysis of the terminally blocked apolar decapeptide pBrBz-(Aib-L-Ala)5-OMe bis-dimethylsulfoxide solvate was performed by x-ray diffraction. The peptide molecules are basically alpha-helical with five 1<--5 C = O... H-N intramolecular H bonds. Near the C terminus the regularity of the alpha-helix is disrupted in favor of the formation of intramolecular H bonds of the 1<--4 (beta-bend) and 1<--6 (pi-bend) types. Differences in conformation, solvation and association with the published structure of the tetrahydrate decapeptide polymorph are discussed.
University of Naples, Italy.
B
B
Di Blasio
V
V
Pavone
M
M
Saviano
R
R
Fattorusso
C
C
Pedone
E
E
Benedetti
M
M
Crisma
C
C
Toniolo
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003460:Crystallization; D018360:Crystallography, X-Ray; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry*; D011487:Protein Conformation; D017433:Protein Structure, Secondary
D009842:Oligopeptides