Cerrini S, Lamba D, Scatturin A, Ughetto G
Biopolymers. 1989 Jan;28(1):409-20. doi: 10.1002/bip.360280138.
The crystal and molecular structure of the nonapeptide antibiotic leucinostatin A, containing some uncommon amino acids and three Aib residues, has been determined by x-ray diffraction analysis. The molecule crystallizes in the orthorhombic space group P2(1)2(1)2(1), a = 10.924, b = 17.810, c = 40.50 A, C62H111N11O13, HCl.H2O, Z = 4. The peptide backbone folds in a regular right-handed alpha-helix conformation, with six intramolecular i----(i + 4) hydrogen bonds, forming C13 rings. The nonapeptide chain includes at the C end an unusual beta-Ala residue, which also adopts the helical structure of the other eight residues. In the crystal the helices are linked head to tail by electrostatic and hydrogen-bond interactions, forming continuous helical rods. The crystal packing is formed by adjacent parallel and antiparallel helical rods. Between adjacent parallel helical columns there are only van der Waals contacts, while between adjacent antiparallel helical columns hydrogen-bond interactions are formed.
已通过X射线衍射分析确定了含有一些不常见氨基酸和三个Aib残基的九肽抗生素亮抑菌素A的晶体和分子结构。该分子结晶于正交空间群P2(1)2(1)2(1)，a = 10.924，b = 17.810，c = 40.50 Å，C62H111N11O13，HCl·H2O，Z = 4。肽主链折叠成规则的右手α-螺旋构象，具有六个分子内i----(i + 4)氢键，形成C13环。九肽链在C端包含一个不寻常的β-丙氨酸残基，其也采用其他八个残基的螺旋结构。在晶体中，螺旋通过静电和氢键相互作用首尾相连，形成连续的螺旋棒。晶体堆积由相邻的平行和反平行螺旋棒形成。在相邻的平行螺旋柱之间只有范德华接触，而在相邻的反平行螺旋柱之间形成氢键相互作用。
