Vellieux F M, Hajdu J, Verlinde C L, Groendijk H, Read R J, Greenhough T J, Campbell J W, Kalk K H, Littlechild J A, Watson H C
Department of Chemistry, BIOSON Research Institute, University of Groningen, The Netherlands.
Proc Natl Acad Sci U S A. 1993 Mar 15;90(6):2355-9. doi: 10.1073/pnas.90.6.2355.
The three-dimensional structure of glycosomal glyceraldehyde-3-phosphate dehydrogenase [D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.12.1.12] from the sleeping-sickness parasite Trypanosoma brucei was solved by molecular replacement at 3.2-A resolution with an x-ray data set collected by the Laue method. For data collection, three crystals were exposed to the polychromatic synchrotron x-ray beam for a total of 20.5 sec. The structure was solved by using the Bacillus stearothermophilus enzyme model [Skarzyński, T., Moody, P. C. E. & Wonacott, A. J. (1987) J. Mol. Biol. 193, 171-187] with a partial data set which was 37% complete. The crystals contain six subunits per asymmetric unit, which allowed us to overcome the absence of > 60% of the reflections by 6-fold density averaging. After molecular dynamics refinement, the current molecular model has an R factor of 17.6%. Comparing the structure of the trypanosome enzyme with that of the homologous human muscle enzyme, which was determined at 2.4-A resolution, reveals important structural differences in the NAD binding region. These are of great interest for the design of specific inhibitors of the parasite enzyme.
利用劳厄法收集的X射线数据集，通过分子置换法在3.2埃分辨率下解析了来自昏睡病寄生虫布氏锥虫的糖体甘油醛-3-磷酸脱氢酶[D-甘油醛-3-磷酸：NAD⁺氧化还原酶（磷酸化），EC 1.12.1.12]的三维结构。为了进行数据收集，将三块晶体暴露于多色同步加速器X射线下，总共照射20.5秒。通过使用嗜热脂肪芽孢杆菌酶模型[Skarzyński, T., Moody, P. C. E. & Wonacott, A. J. (1987) J. Mol. Biol. 193, 171 - 187]和一个完整性为37%的部分数据集来解析该结构。晶体每个不对称单元包含六个亚基，这使我们能够通过六重密度平均克服超过60%的反射缺失。经过分子动力学精修后，当前的分子模型R因子为17.6%。将锥虫酶的结构与在2.4埃分辨率下测定的同源人类肌肉酶的结构进行比较，发现在NAD结合区域存在重要的结构差异。这些差异对于设计该寄生虫酶的特异性抑制剂具有重要意义。
