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用浸泡法得到了（Ｅ１６０Ａ）天花粉蛋白（ｔｒｉｃｈｏｓａｎｔｈｉｎ， ＴＣＳ），（Ｅ１６０Ｄ）ＴＣＳ与Ａｄｅ 和（Ｅ１６０Ａ）ＴＣＳ与ＦＭＰ复合物的晶体．在Ｍａｒ Ｒｅｓｅａｒｃｈ 面探测器系统上分别收集了０．２０ ｎｍ ，０．１９ｎｍ 和０．２０５ ｎｍ 分辨率的Ｘ 射线衍射数据，数据处理用Ｍａｒ Ｓｃａｌｅ 程序系统完成．用同晶差值Ｆｏｕｒｉｅｒ法解析了（Ｅ１６０Ａ）ＴＣＳ－Ａｄｅ，（Ｅ１６０Ｄ）ＴＣＳ－Ａｄｅ 和（Ｅ１６０Ａ）ＴＣＳ－ＦＭＰ的晶体结构，结构修正利用Ｘ－ＰＬＯＲ程序，修正结果，晶体学Ｒ因子分别为０．１６６，０．１７６，０．１７９．键长和键角的ＲＭＳ偏差分别为０．００１０ ｎｍ 和２．５０３°，０．００１３ ｎｍ 和２．６６５°，０．００１２ ｎｍ 和２．６７６°．在这三个结构中均未见到Ｇｌｕ１８９侧链方向的改变．Ａｄｅ 或ＦＭＰ仍结合在Ｎ－糖苷酶活性口袋之中，它夹在Ｔｙｒ７０和Ｔｙｒ１１１两个侧链环之间，与Ｔｙｒ７０环近乎平行．这一结果表明：ＴＣＳ中的Ｇｌｕ１６０分别突变成Ａｌａ 和Ａｓｐ，仍能与ＡＭＰ发生Ｎ－糖苷酶反应，但是活性降低了一些．可见Ｇｌｕ１６０对ＴＣＳ与ＡＭＰ的作用是重要的，但不是必要的．
The crystals of (E160A) trichosanthin (TCS), (E160D) TCS and Ade and (E160A) TCS and FMP complexes were obtained by soaking. X-ray diffraction data were collected at resolutions of 0.20 nm, 0.19 nm and 0.205 nm respectively on the Mar Research surface detector system. Data processing was performed using the Mar Scale program system. The crystal structures of (E160A) TCS-Ade, (E160D) TCS-Ade and (E160A) TCS-FMP were elucidated by the method of isothermal difference Fourier analysis. The structure was corrected by X-PLOR program. 0.166, 0.166, 0.179. The RMS deviation of bond length and bond angle is 0.0010 nm and 2.503 °, 0.0013 nm and 2.665 °, 0.0012 nm and 2.676 °, respectively. No change in the orientation of Glu189 side chain was observed in any of these three structures. Ade or FMP still binds to the N-glycosidase activity pocket, which is sandwiched between two side-chain loops of Tyr70 and Tyr111, nearly parallel to the Tyr70 loop. This result indicates that Glu160 in TCS mutates to Ala and Asp, respectively, and still can react with AMP N-glycosidase, but its activity is reduced. Visible Glu160 on TCS and AMP role is important, but not necessary.