title: Exhaustive crystal structure search and crystal modeling of beta-chitin.
abstract: An exhaustive search of the crystal structure of beta-chitin was carried out by simultaneously optimizing all the structural parameters based on published X-ray diffraction data and stereochemical criteria. The most probable structure was characterized by a parallel-up chain polarity, a gg orientation of hydroxymethyl groups and an intermolecular hydrogen bond along the a-axis, which essentially reproduced the original structure proposed by Gardner and Blackwell. The proposed crystal structure was subsequently subjected to crystal modeling using the AMBER force field. The probable orientation of hydroxyl groups and their motional behaviors is proposed based on calculations for the crystal models identified. Solvated crystal models exhibited a slightly deformed structure with the formation of appreciable numbers of hydrogen bonds along the b-axis.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, University of Miyazaki, Nsihi 1-1, Gakuen-kibanadai, Miyazaki, Miyazaki 889-2192, Japan. tyui@cc.miyazaki-u.ac.jp
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Yui
authors.forename: Naoto
authors.initials: N
authors.lastname: Taki
authors.forename: Junji
authors.initials: J
authors.lastname: Sugiyama
authors.forename: Sachio
authors.initials: S
authors.lastname: Hayashi
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D002686:Chitin / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular
chemical_list: D002686:Chitin