School of Chemistry, Cardiff University, Park Place, Wales, United Kingdom.
J Struct Biol. 2011 Jun;174(3):461-7. doi: 10.1016/j.jsb.2011.03.001. Epub 2011 Mar 5.
We report the crystal structure of the 5-residue peptide acetyl-YEQGL-amide, determined directly from powder X-ray diffraction data recorded on a conventional laboratory X-ray powder diffractometer. The YEQGL motif has a known biological role, as a trafficking motif in the C-terminus of mammalian P2X4 receptors. Comparison of the crystal structure of acetyl-YEQGL-amide determined here and that of a complex formed with the μ2 subunit of the clathrin adaptor protein complex AP2 reported previously, reveals differences in conformational properties, although there are nevertheless similarities concerning aspects of the hydrogen-bonding arrangement and the hydrophobic environment of the leucine sidechain. Our results demonstrate the potential for exploiting modern powder X-ray diffraction methodology to achieve complete structure determination of materials of biological interest that do not crystallize as single crystals of suitable size and quality for single-crystal X-ray diffraction.
我们报告了 5 残基肽乙酰-YEQGL-酰胺的晶体结构，该结构是直接从常规实验室 X 射线粉末衍射仪上记录的粉末 X 射线衍射数据中确定的。YEQGL 基序具有已知的生物学作用，作为哺乳动物 P2X4 受体 C 末端的运输基序。这里确定的乙酰-YEQGL-酰胺的晶体结构与以前报道的网格蛋白衔接蛋白复合物 AP2 的 μ2 亚基形成的复合物的晶体结构进行比较，揭示了构象特性的差异，尽管在氢键排列和亮氨酸侧链的疏水环境方面仍然存在相似之处。我们的结果表明，利用现代粉末 X 射线衍射方法来实现对生物感兴趣的材料的完整结构测定具有潜力，这些材料不能结晶成适合于单晶 X 射线衍射的单晶，且尺寸和质量合适。
