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Glide打分函数中蛋白间打分噪音的发现和修正
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摘要
极少小分子药物在与其靶点蛋白相互作用中具有足够的专一选择性。药物与非预期的非靶点蛋白结合常常导致副作用,但偶尔也引发一些新的治疗作用。因此,识别化合物的非靶点蛋白对于评价该化合物的研发潜力具有重要意义。在计算生物学中,反向对接的方法可以预测化合物的靶点蛋白。反向对接使用一个化合物(诱饵)对蛋白质库(猎物)进行虚拟筛选,这与正常对接过程中使用蛋白质(诱饵)对小分子库(猎物)进行筛选相反。
     本研究发现,在反向对接过程中对打分函数的针对性优化能够提高靶点蛋白预测的准确性。本研究选择的标准数据集Astex Diverse数据集是一个含有85个配体-受体蛋白复合物,且结构多样性的高质量数据集。对接软件Glide中的“标准精度”模式下的打分函数GlideScore,能够精确重复该数据集中58个配体小分子-受体蛋白复合物的晶体结合构象。但在针对这58个复合物的反向对接过程中,GlideScore只能够正确识别57%的配体小分子-受体蛋白关系。其原因可能是GlideScore对某些蛋白过高或者过低的打分,即GlideScore存在不同蛋白之间的噪音。分析成功和失败的反向对接例子发现,蛋白质特性“Balance"与反向对接的结果强烈相关。"Balance"为靶点蛋白结合位点的疏水性面积和亲水性面积之间的比值。通过引入一个以"Balance"为核心的修正项,能将小分子靶点蛋白的预测准确性提高27%(从57%提升至72%)。新的打分函数命名为BCGlideScore,它在另一个同质的额外测试集上也能以类似的幅度提高反向对接的准确率29%(从47%提升至60%)。分析发现,BCGlideScore的三个特性与提高反向对接准确率有关:加入的修正项能够减少“蛋白间”的噪音;加入修正项后的BCGlideScore与"Balance"之间的相关性减少;修正项可能代表了一个粗糙的蛋白质熵的变化的估计。
     “额外精度”模式为Glide中的另一个分子对接模式。该模式中的构象搜索算法和打分函数是为了更好的估计配体-受体蛋白亲和力而优化。使用与“标准精度”模式类似的分析流程发现,“额外精度”模式中获得最高反向对接准确率的打分函数XPEmodelScore同样存在“蛋白间”的噪音,但是由于候选小分子和蛋白特性种类和数量有限,没能成功发现与XPEmodelScore中“蛋白间”噪音强烈相关的特性,也就不能修正XPEmodelScore。我们提出相互作用的指纹描述有很大的潜能用来修正“蛋白间”噪音。另外,尽管显著提高打分函数与亲和力之间的相关性,能够提高化合物库筛选与蛋白质库筛选的准确性。但是,我们的结果显示XPGlideScore与亲和力的相关性稍高于标准模式下的GlideScore,但与GlideScore57%的反向对接准确率相比,XPGlideScore并不能很好的预测靶点(仅仅22%的正确率),这表示少量的提高打分函数与亲和力之间的相关性,未必能够转化成蛋白质库筛选准确性的提高。
     本研究还发现,分子对接中三个打分目标(预测最优结合构象、预测能够与受体蛋白结合的小分子和预测小分子靶点蛋白)分别侧重于配体-受体蛋白结合的不同方面。因此,为各自不同的目标开发专门的打分函数将会是可行和更加有效的。尽管能够满足所有目标的“全能”打分函数是存在的,但这种打分函数往往需要很大的计算量。而为不同的打分目的开发专门的功能,能够为每个专门的功能减少对精确度要求而减少计算量。同时,准备更全面,更有代表性的数据集来训练和测试更多专门的打分函数可能更加容易。因此,将打分目标分开可能是发展更加简单但更有效的打分系统的关键。
     这是目前首次对反向对接中打分函数的蛋白间噪音的报道和修正,我们希望本次研究能够引起对所有打分函数中类似蛋白间噪音的进一步研究和规范,最终能够使用反向对接更准确地预测小分子化合物的作用靶点。我们也将继续为发展针对反向对接的打分函数而继续努力。
Small molecule drugs are rarely selective enough to interact solely with their designated targets. Unintended "off-target" interactions often lead to side effects, but also serendipitously lead to new therapeutic uses. Identification of the off-targets of a compound is therefore of significant value to the evaluation of its developmental potential. In computational biology, the strategy of "reverse docking" has been introduced to predict the targets of a compound, which uses a compound to virtually screen a library of proteins, reversing the bait and prey in "normal" docking screenings.
     The present study shows that, in reverse docking, additional optimization of the scoring function may help to improve the target prediction accuracy. We chose Astex Diverse dataset which was a diverse, high-quality dataset containing 85 ligand-protein complexes as our standard example dataset. GlideScore in the "standard precision" mode of Glide could accurately reproduce the crystal binding conformation of 58 complexes in Astex Diverse dataset. But in the reverse docking of those 58 complexes, we found that only 57% of the ligand-protein relationships could be correctly identified. This was likely a result of the constant over-or under-estimation of the GlideScores for specific proteins. In other words, there were interprotein noises in the Glidescores. Using decision tree to classify the successful and unsuccessful reverse docking cases, we found a protein descriptor balance was strongly associated with successful/unsuccessful target predictions. The balance descriptor expresses the ratio of the relative hydrophobic and hydrophilic character of the binding site. Introducing a correction term based on balance improved the target-prediction accuracy by 27%(57-72%). And the new score was named BCGlideScore. It also improved the target-prediction accuracy by 29%(47-60%) on an external test dataset having a similar quality to the Astex Diverse dataset. BCGlideScore had three features associated with the target-prediction improvement:the balance based correction term corrected of the "interpocket" noises, the correction term reduced the correction between the balance descriptor and the BCGlideScore and the correction term might represent a rough estimation of protein entropic changes.
     The "extra precision" mode (XP) whose conformation search and scoring function are optimized for better correlation between docking score and binding affinity is another mode in Glide for molecular docking. Using a similar analyzing protocol with "standard precision" mode, we found XPEmodelScore showed the highest accuracy in target prediction and our data indicated that there were interprotein noises in the XPEmdoelScores. However, unfortunately, we were unable to identify any ligand or protein property that was strongly associated with the noises and had the potential to correct XPEmodelScores. This was likely a result of our small descriptor pool. With more descriptors to characterize the ligand/protein properties, we might be able to find one suitable property for noise correction. In this regard, interaction-fingerprints may have a big potential to be used for this purpose. In addition, it is for sure that significantly increased correlation between docking score and binding affinity will improve the prediction accuracy in both compound library screening and protein library screening. But our results showed that the XPGlideScores did show better correlation with binding affinity than the standard mode GlideScores. XPGlideScore showed poor performance in target prediction (only 22.0% success) comparing with GlideScore's accuracy of 57%. The above results suggested that slightly improved correlation may not necessarily translate to improved accuracy in protein library screening.
     We also found that each of the docking scoring objectives (the prediction of the optimal binding conformation, the prediction of the potential protein-binding ligands and the prediction of the potential of targets of a ligand) emphasizes on different aspects of ligand-protein binding. So it may be possible and more effective to develop specialized scoring functions for individual objectives. Theoretically, an omnipurpose scoring function exists, but it always requires intensive computation to estimate. Developing specialized functions for different scoring objectives is a strategy that can reduce the precision requirement for each specialized function. Preparing more comprehensive and representative datasets to train and test more specialized scoring functions might be easier. Therefore, separation of scoring objectives may hold to key to developing simpler yet more effective scoring syste
     This is the first discussion about the discovery and correction of the interprotein scoring noises in reverse docking. It is our hope that this focused discussion on the Glide scores would invite further efforts to characterize and normalize this type of interprotein noises in all docking scores, so that better target prediction accuracy can be achieved with the strategy of reverse docking. And we will continue to work for developing specialized scoring functions for reverse docking.
引文
1. Bosch, F. and L. Rosich, The contributions of Paul Ehrlich to pharmacology:a tribute on the occasion of the centenary of his Nobel Prize. Pharmacology,2008.82(3):p.171-9.
    2. Dahl, S.G. and I. Sylte, Molecular modelling of drug targets:the past, the present and the future. Basic & clinical pharmacology & toxicology,2005.96(3):p.151-5.
    3. Drews, J., Drug discovery:a historical perspective. Science,2000.287(5460):p.1960-4.
    4. Peterson, R.T., Chemical biology and the limits of reductionism. Nature chemical biology,2008. 4(11):p.635-8.
    5. Nobeli, I., A.D. Favia, and J.M. Thornton, Protein promiscuity and its implications for biotechnology. Nature biotechnology,2009.27(2):p.157-67.
    6. Marona-Lewicka, D. and D.E. Nichols, Further evidence that the delayed temporal dopaminergic effects of LSD are mediated by a mechanism different than the first temporal phase of action. Pharmacology, biochemistry, and behavior,2007.87(4):p.453-61.
    7. Marona-Lewicka, D. and D.E. Nichols, WAY 100635 produces discriminative stimulus effects in rats mediated by dopamine D(4) receptor activation. Behavioural pharmacology,2009. 20(1):p.114-8.
    8. FDA, Innovation or stagnation:challenge and opportunity on the critical path to new medical products.. http://www.fda.gov/ ScienceResearch/SpecialTopics/CriticalPathInitiative/CriticalPath OpportunitiesReports/ucm077262.htm.,2004.
    9. Bunnage, M.E., Getting pharmaceutical R&D back on target. Nature chemical biology,2011. 7(6):p.335-9.
    10. Brown, D. and G. Superti-Furga, Rediscovering the sweet spot in drug discovery. Drug Discov Today,2003.8(23):p.1067-77.
    11. Pardanani, A. and A. Tefferi, Imatinib targets other than bcr/abl and their clinical relevance in myeloid disorders. Blood,2004.104(7):p.1931-1939.
    12. Overington, J.P., B. Al-Lazikani, and A.L. Hopkins, How many drug targets are there? Nature reviews. Drug discovery,2006.5(12):p.993-6.
    13. Landry, Y. and J.P. Gies, Drugs and their molecular targets:an updated overview. Fundamental & clinical pharmacology,2008.22(1):p.1-18.
    14. Merino, A., et al., Drug profiling:knowing where it hits. Drug discovery today,2010. 15(17-18):p.749-56.
    15. McCulley, T.J., et al., Acute effects of sildenafil (viagra) on blue-on-yellow and white-on-white Humphrey perimetry. J Neuroophthalmol,2000.20(4):p.227-8.
    16. Roth, B.L., Drugs and valvular heart disease. The New England journal of medicine,2007. 356(1):p.6-9.
    17. Henkel, J., Attacking AIDS with a 'cocktail' therapy? FDA consumer,1999.33(4):p.12-7.
    18. Furukawa, K., et al., Efficacy and safety of combined trastuzumab and Paclitaxel therapy as a second-line treatment in women with metastatic breast cancer:a single institutional experience. Breast Cancer,2006.13(4):p.329-33.
    19. Ishiguro, M., et al., Effect of combined therapy with low-dose 5-aza-2'-deoxycytidine and irinotecan on colon cancer cell line HCT-15. Annals of surgical oncology,2007.14(5):p. 1752-62.
    20. Borisy, A.A., et al., Systematic discovery of multicomponent therapeutics. Proceedings of the National Academy of Sciences of the United States of America,2003.100(13):p.7977-7982.
    21. Chen, X., et al., Database of traditional Chinese medicine and its application to studies of mechanism and to prescription validation. British journal of pharmacology,2006.149(8):p. 1092-103.
    22. Sengupta, S., et al., Modulating angiogenesis:the yin and the yang in ginseng. Circulation, 2004.110(10):p.1219-25.
    23. Xue, T. and R. Roy, Studying traditional Chinese medicine. Science,2003.300(5620):p. 740-1.
    24. Marton, M.J., et al., Drug target validation and identification of secondary drug target effects using DNA microarrays. Nature medicine,1998.4(11):p.1293-301.
    25. Zhu, H. and M. Snyder, Protein chip technology. Current opinion in chemical biology,2003. 7(1):p.55-63.
    26. Burbaum, J. and G.M. Tobal, Proteomics in drug discovery. Current opinion in chemical biology,2002.6(4):p.427-33.
    27. Bantscheff, M., A. Scholten, and A.J. Heck, Revealing promiscuous drug-target interactions by chemical proteomics. Drug discovery today,2009.14(21-22):p.1021-9.
    28. Parks, D.J., et al., Bile acids:natural ligands for an orphan nuclear receptor. Science,1999. 284(5418):p.1365-8.
    29. MacDonald, M.L., et al., Identifying off-target effects and hidden phenotypes of drugs in human cells. Nature chemical biology,2006.2(6):p.329-37.
    30. Chen, X., C.Y. Ung, and Y.Z. Chen, Can an in silico drug-target search method be used to probe potential mechanisms of medicinal plant ingredients? Natural Product Reports,2003. 20(4):p.432-444.
    31. Leach, A.R., B.K. Shoichet, and C.E. Peishoff, Prediction of protein-ligand interactions. Docking and scoring:successes and gaps. Journal of medicinal chemistry,2006.49(20):p. 5851-5.
    32. Chen, Y.Z. and D.G. Zhi, Ligand-protein inverse docking and its potential use in the computer search of protein targets of a small molecule. Proteins,2001.43(2):p.217-26.
    33. Chen, Y.Z. and C.Y. Ung, Prediction of potential toxicity and side effect protein targets of a small molecule by a ligand-protein inverse docking approach. Journal of Molecular Graphics & Modelling,2001.20(3):p.199-218.
    34. Verdonk, M.L., et al., Improved protein-ligand docking using GOLD. Proteins,2003.52(4):p. 609-23.
    35. Kellenberger, E., et al., sc-PDB:an annotated database of druggable binding sites from the Protein Data Bank. Journal of chemical information and modeling,2006.46(2):p.717-27.
    36. Halgren, T.A., et al., Glide:a new approach for rapid, accurate docking and scoring.2. Enrichment factors in database screening. J Med Chem,2004.47(7):p.1750-9.
    37. Paul, N., et al., Recovering the true targets of specific ligands by virtual screening of the protein data bank. Proteins,2004.54(4):p.671-80.
    38. Muller, P., et al., In silico-guided target identification of a scaffold-focused library: 1,3,5-triazepan-2,6-diones as novel phospholipase A2 inhibitors. Journal of medicinal chemistry,2006.49(23):p.6768-78.
    39. Gao, Z., et al., PDTD:a web-accessible protein database for drug target identification. BMC Bioinformatics,2008.9:p.104.
    40. Ewing, T.J., et al., DOCK 4.0:search strategies for automated molecular docking of flexible molecule databases. Journal of computer-aided molecular design,2001.15(5):p.411-28.
    41. Li, H., et al., TarFisDock:a web server for identifying drug targets with docking approach. Nucleic acids research,2006.34(Web Server issue):p. W219-24.
    42. Cai, J., et al., Peptide deformylase is a potential target for anti-Helicobacter pylori drugs: reverse docking, enzymatic assay, and X-ray crystallography validation. Protein science:a publication of the Protein Society,2006.15(9):p.2071-81.
    43. Tietze, S. and J. Apostolakis, GlamDock:development and validation of a new docking tool on several thousand protein-ligand complexes. Journal of chemical information and modeling, 2007.47(4):p.1657-72.
    44. Zahler, S., et al., Inverse in silico screening for identification of kinase inhibitor targets. Chemistry & biology,2007.14(11):p.1207-14.
    45. Kitchen, D.B., et al., Docking and scoring in virtual screening for drug discovery:methods and applications. Nature reviews. Drug discovery,2004.3(11):p.935-49.
    46. Taylor, R.D., P.J. Jewsbury, and J.W. Essex, A review of protein-small molecule docking methods. Journal of computer-aided molecular design,2002.16(3):p.151-66.
    47. Kellenberger, E., N. Foata, and D. Rognan, Ranking targets in structure-based virtual screening of three-dimensional protein libraries:methods and problems. Journal of chemical information and modeling,2008.48(5):p.1014-25.
    48. Marcou, G. and D. Rognan, Optimizing fragment and scaffold docking by use of molecular interaction fingerprints. Journal of chemical information and modeling,2007.47(1):p. 195-207.
    49. Flower, D.R., On the properties of bit string-based measures of chemical similarity. Journal of Chemical Information & Computer Sciences,1998.38(3):p.379-386.
    50. Garrido Cantarero, G. and R. Madero Jarabo, [The area under the ROC curve]. Medicina clinica,1996.106(9):p.355-6.
    51. Yang, L., et al., SePreSA:a server for the prediction of populations susceptible to serious adverse drug reactions implementing the methodology of a chemical-protein interactome. Nucleic acids research,2009.37(Web Server issue):p. W406-12.
    52. Friesner, R.A., et al., Glide:a new approach for rapid, accurate docking and scoring.Ⅰ. Method and assessment of docking accuracy. J Med Chem,2004.47(7):p.1739-49.
    53. Shen, J., et al., Discovery of potent ligands for estrogen receptor beta by structure-based virtual screening. J Med Chem,2010.53(14):p.5361-5.
    54. McRobb, F.M., et al., Homology Modeling and Docking Evaluation of Aminergic G Protein-Coupled Receptors. Journal of Chemical Information and Modeling,2010.50(4):p. 626-637.
    55. Cortial, S., et al., NADH oxidase activity of Bacillus subtilis nitroreductase NfrA1:insight into its biological role. FEBS Lett,2010.584(18):p.3916-22.
    56. Moitessier, N., et al., Towards the development of universal, fast and highly accurate docking/scoring methods:a long way to go. Br J Pharmacol,2008.153 Suppl 1:p. S7-26.
    57. Cross, J.B., et al., Comparison of several molecular docking programs:pose prediction and virtual screening accuracy. J Chem Inf Model,2009.49(6):p.1455-74.
    58. Li, X., et al., Evaluation of the performance of four molecular docking programs on a diverse set of protein-ligand complexes. J Comput Chem,2010.31(11):p.2109-25.
    59. Eldridge, M.D., et al., Empirical scoring functions:Ⅰ. The development of a fast empirical scoring function to estimate the binding affinity of ligands in receptor complexes. J Comput Aided Mol Des,1997.11(5):p.425-45.
    60. Baxter, C.A., et al., Flexible docking using Tabu search and an empirical estimate of binding affinity. Proteins,1998.33(3):p.367-82.
    61. Kaminski, G.A., et al., Evaluation and reparametrization of the OPLS-AA force field for proteins via comparison with accurate quantum chemical calculations on peptides. Journal of Physical Chemistry B,2001.105(28):p.6474-6487.
    62. Eldridge, M.D., et al., Empirical scoring functions:Ⅰ. The development of a fast empirical scoring function to estimate the binding affinity of ligands in receptor complexes. Journal of computer-aided molecular design,1997.11(5):p.425-45.
    63. Wang, R., et al., The PDBbind database:collection of binding affinities for protein-ligand complexes with known three-dimensional structures. J Med Chem,2004.47(12):p.2977-80.
    64. Berman, H.M., et al., The Protein Data Bank. Acta Crystallogr D Biol Crystallogr,2002.58(Pt 6 No 1):p.899-907.
    65. Chen, H., et al., On evaluating molecular-docking methods for pose prediction and enrichment factors. J Chem Inf Model,2006.46(1):p.401-15.
    66. Jones, G., et al., Development and validation of a genetic algorithm for flexible docking. J Mol Biol,1997.267(3):p.727-48.
    67. Kramer, B., M. Rarey, and T. Lengauer, Evaluation of the FLEXX incremental construction algorithm for protein-ligand docking. Proteins,1999.37(2):p.228-41.
    68. Pang, Y.P., et al., EUDOC:a computer program for identification of drug interaction sites in macromolecules and drug leads from chemical databases. J Comput Chem,2001.22(15):p. 1750-1771.
    69. Nissink, J.W., et al., A new test set for validating predictions of protein-ligand interaction. Proteins,2002.49(4):p.457-71.
    70. Paul, N. and D. Rognan, ConsDock:A new program for the consensus analysis of protein-ligand interactions. Proteins,2002.47(4):p.521-33.
    71. Friesner, R.A., et al., Glide:a new approach for rapid, accurate docking and scoring.1. Method and assessment of docking accuracy. Journal of medicinal chemistry,2004.47(7):p. 1739-49.
    72. Hartshorn, M.J., et al., Diverse, high-quality test set for the validation of protein-ligand docking performance. J Med Chem,2007.50(4):p.726-41.
    73. Hendlich, M., et al., Relibase:design and development of a database for comprehensive analysis of protein-ligand interactions. J Mol Biol,2003.326(2):p.607-20.
    74. Liu, T., et al., BindingDB:a web-accessible database of experimentally determined protein-ligand binding affinities. Nucleic Acids Res,2007.35(Database issue):p. D198-201.
    75. Muller, P., et al., In silico-guided target identification of a scaffold-focused library: 1,3,5-triazepan-2,6-diones as novel phospholipase A2 inhibitors. J Med Chem,2006.49(23):p. 6768-78.
    76. Li, H., et al., TarFisDock:a web server for identifying drug targets with docking approach. Nucleic Acids Res,2006.34(Web Server issue):p. W219-24.
    77. Cai, J., et al., Peptide deformylase is a potential target for anti-Helicobacter pylori drugs: reverse docking, enzymatic assay, and X-ray crystallography validation. Protein Sci,2006. 15(9):p.2071-81.
    78. Zahler, S., et al., Inverse in silico screening for identification of kinase inhibitor targets. Chem Biol,2007.14(11):p.1207-14.
    79. Kellenberger, E., N. Foata, and D. Rognan, Ranking targets in structure-based virtual screening of three-dimensional protein libraries:methods and problems. J Chem Inf Model, 2008.48(5):p.1014-25.
    80. Halgren, T., New method for fast and accurate binding-site identification and analysis. Chemical Biology & Drug Design,2007.69(2):p.146-148.
    81. Halgren, T.A., Identifying and Characterizing Binding Sites and Assessing Druggability. Journal of Chemical Information and Modeling,2009.49(2):p.377-389.
    82. Flower, D.R., On the Properties of Bit String-Based Measures of Chemical Similarity. J. Chem. Inf. Comput. Sci.,1998.38:p.379-386.
    83. Guha, R., et al., The Blue Obelisk-interoperability in chemical informatics. J Chem Inf Model, 2006.46(3):p.991-8.
    84. Jacobsson, M. and A. Karlen, Ligand bias of scoring functions in structure-based virtual screening. J Chem Inf Model,2006.46(3):p.1334-43.
    85. Carta, G., A.J. Knox, and D.G. Lloyd, Unbiasing scoring functions:a new normalization and rescoring strategy. J Chem Inf Model,2007.47(4):p.1564-71.
    86. Kitchen, D.B., et al., Docking and scoring in virtual screening for drug discovery:methods and applications. Nat Rev Drug Discov,2004.3(11):p.935-49.
    87. Seifert, M.H., Targeted scoring functions for virtual screening. Drug Discov Today,2009. 14(11-12):p.562-9.
    88. Kearns, M. and D. Ron, Algorithmic stability and sanity-check bounds for leave-one-out cross-validation. Neural Comput,1999.11(6):p.1427-53.
    89. Kellenberger, E., et al., sc-PDB:an annotated database of druggable binding sites from the Protein Data Bank. J Chem Inf Model,2006.46(2):p.717-27.
    90. Chang, C.E., W. Chen, and M.K. Gilson, Ligand configurational entropy and protein binding. Proc Natl Acad Sci U S A,2007.104(5):p.1534-9.
    91. Murray, C.W. and M.L. Verdonk, The consequences of translational and rotational entropy lost by small molecules on binding to proteins. J Comput Aided Mol Des,2002.16(10):p. 741-53.
    92. Gilson, M.K. and H.X. Zhou, Calculation of protein-ligand binding affinities. Annu Rev Biophys Biomol Struct,2007.36:p.21-42.
    93. Pan, Y., et al., Consideration of molecular weight during compound selection in virtual target-based database screening. J Chem Inf Comput Sci,2003.43(1):p.267-72.
    94. Cheng, T., et al., Comparative assessment of scoring functions on a diverse test set. J Chem Inf Model,2009.49(4):p.1079-93.
    95. Warren, G.L., et al., A critical assessment of docking programs and scoring functions. J Med Chem,2006.49(20):p.5912-31.
    96. Woo, H.J. and B. Roux, Calculation of absolute protein-ligand binding free energy from computer simulations. Proc Natl Acad Sci U S A,2005.102(19):p.6825-30.
    97. Friesner, R.A., et al., Extra precision glide:docking and scoring incorporating a model of hydrophobic enclosure for protein-ligand complexes. J Med Chem,2006.49(21):p.6177-96.
    98. Perez-Nueno, V.I., et al., APIF:a new interaction fingerprint based on atom pairs and its application to virtual screening. J Chem Inf Model,2009.49(5):p.1245-60.
    99. Rognan, D., Development and virtual screening of target libraries. J Physiol Paris,2006. 99(2-3):p.232-44.
    100. Wang, L., et al., Dissection of mechanisms of Chinese medicinal formula Realgar-Indigo naturalis as an effective treatment for promyelocytic leukemia. Proceedings of the National Academy of Sciences of the United States of America,2008.105(12):p.4826-31.

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