A second polymorph of a helical decapeptide.

B Di Blasio; V Pavone; M Saviano; R Fattorusso; C Pedone; E Benedetti; M Crisma; C Toniolo

PubMed · 8012121

A second polymorph of a helical decapeptide.

B Di Blasio·V Pavone·M Saviano·R Fattorusso·C Pedone·E Benedetti·M Crisma·C Toniolo

Abstract

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.

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Chemical Phenomena Chemistry, Physical Crystallization Crystallography, X-Ray Molecular Structure Oligopeptides Protein Conformation Protein Structure, Secondary Journal Article

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B Di Blasio, V Pavone, M Saviano, R Fattorusso, C Pedone, E Benedetti, M Crisma, C Toniolo. A second polymorph of a helical decapeptide.. https://pubmed.ncbi.nlm.nih.gov/8012121/

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