X-ray diffraction and side chain structure of poly(.ALPHA.-amino acid)s having long side chains. Temperature dependence of scattering intensity.

DOI Web Site
  • TEDUKA Masao
    Department of Applied Physics, Faculty of Engineering, Hokkaido University
  • TSUTSUMI Akihiro
    Department of Applied Physics, Faculty of Engineering, Hokkaido University
  • MATSUSHIMA Norio
    School of Allied Health Professions, Sapporo Medical College
  • CHIBA Akio
    Department of Applied Physics, Waseda University

Bibliographic Information

Other Title
  • 長い側鎖をもつポリアミノ酸のＸ線回折と側鎖の構造　散乱強度の温度依存性の解釈
  • ナガイ ソクサ オ モツ ポリアミノサン ノ Xセン カイセツ ト ソクサ ノ
  • Temperature Dependence of Scattering Intensity
  • 散乱強度の温度依存性の解釈

Search this article

Description

It has been reported that the intensity of X-ray diffraction of poly- (γ-methyl L-glutamate) (PMLG) and poly (γ-benzyl L-glutamate) (PBLG) in the solid state, which are typical polypeptides, increases with increase of temperature. This has been explained by a 2 phase model, composed of rigid helical cores and flexible side chain regions. In this work, we have investigated the X-ray diffraction of the copolymers of γ-methyl L-glutamate and γ-pentadecyl L-glutamate in the temperature range from -40 to 60°C and has found that the temperature dependence of the diffraction intensity isnot explained by the 2 phase model. In the polypeptides having long side chains, the crystallization of side chains occurs. In order to interpret the present diffraction results, a new model for the electron density distribution, a 3 phase model, has been proposed. The size of the crystalline phase obtained from the analysis of the diffraction data fairly well agrees with the results of DSC and the specific volume measurements. The 3 phase model expresses the X-ray diffraction of solid α-helical polypeptides having long alkyl side chains with a high degree of substitution.

Journal

  • KOBUNSHI RONBUNSHU

    KOBUNSHI RONBUNSHU 47 (9), 749-756, 1990

    The Society of Polymer Science, Japan

Keywords

Details 詳細情報について

Report a problem

Back to top