title: Bioactive peptides: conformational studies of [Tyr4] cyclolinopeptide A.
abstract: The solid state conformational analysis of [Tyr4] cyclolinopeptide A has been carried out by x-ray diffraction studies. The crystal structure of the monoclinic form, grown from a dioxane-water mixture [alpha = 9.849 (5) A, b = 20.752 (4) A, c = 16.728 (5) A, beta = 98.83 (3) degrees, space group P21, Z = 2], shows the presence of five intramolecular N-H...O = C hydrogen bonds, with formation of one C17 ring structure, one alpha-turn (C13), one inverse gamma-turn (C7), and two beta-turns (C10, one of type III and one of type I). The Pro1-Pro2 peptide unit is cis (omega = 5 degrees), all others are trans. The structure is almost superimposable with that of cyclolinopeptide A. The rms deviation for the atoms of the backbones is on the average 0.33 A.
authors.affiliation: CNR, Università di Napoli Federico II, Dipartimento di Chimica, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Saviano
authors.forename: F
authors.initials: F
authors.lastname: Rossi
authors.forename: M
authors.initials: M
authors.lastname: Filizola
authors.forename: C
authors.initials: C
authors.lastname: Isernia
authors.forename: B
authors.initials: B
authors.lastname: Di Blasio
authors.forename: E
authors.initials: E
authors.lastname: Benedetti
authors.forename: C
authors.initials: C
authors.lastname: Pedone
authors.forename: I Z
authors.initials: IZ
authors.lastname: Siemion
authors.forename: A
authors.initials: A
authors.lastname: Pedyczak
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000737:chemistry*; D011487:Protein Conformation; D017510:Protein Folding
chemical_list: D010456:Peptides, Cyclic; C055018:cyclolinopeptide A; C096284:cyclolinopeptide A, Tyr(4)-