Nagarajan V, Kamitori S, Okuyama K
Department of Biotechnology and Life Science, Faculty of Technology, Tokyo University of Agriculture and Technology, Naka-cho, Koganei-shi, Tokyo, 184-8588, Japan.
J Biochem. 1998 Dec 1;124(6):1117-23. doi: 10.1093/oxfordjournals.jbchem.a022229.
Single crystals of (Pro-Pro-Gly)10 were grown by the hanging drop method. The crystals diffracted to a resolution of 1.8 A. In the crystals the polypeptides form triple helices that aggregate end-to-end mediated by the solvent molecules, with the basic repeat being 20 A along the helical axis. Analysis of the 20 A structure of (Pro-Pro-Gly)10 using data up to a resolution of 1.9 A revealed that the overall structure is in accordance with the 7/2 model proposed for collagen. The three strands are held together by the (Gly) N-H O (Pro-X) hydrogen bond interactions, and additional stability is provided by the (Pro-Y) Calpha -H O (Pro-X) hydrogen bonding interactions.
采用悬滴法生长出了(Pro-Pro-Gly)10的单晶。这些晶体的衍射分辨率达到了1.8埃。在晶体中，多肽形成三螺旋结构，由溶剂分子介导首尾相连聚集在一起，沿螺旋轴的基本重复单元为20埃。利用分辨率高达1.9埃的数据对(Pro-Pro-Gly)10的20埃结构进行分析，结果表明其整体结构符合为胶原蛋白提出的7/2模型。三条链通过(Gly)N-H O(Pro-X)氢键相互作用维系在一起，(Pro-Y)Calpha -H O(Pro-X)氢键相互作用则提供了额外的稳定性。
