Computational virtual screening

Wang RX, Wang SM. How does consensus scoring work for virtual library screening An idealized computer experiment. J Chem Inf Comput Sci 2001 41 1422-6. 

Test a substantial number of compounds. VS methods generally offer enrichment, but most ranked hit lists contain a significant proportion of false positives. Hitlists should be scaled to 1-5% of the compounds in the virtual library screened. In many real world situations, the computational chemist is being asked to choose lists of compounds representing 0.1% or less of the compounds screened (e.g., the best 100 of 100,000 compounds). Typically, VS methods have been validated considering 1%, 5%, or 10% of the total number of compounds in the VS collection. By following up on more compounds, one increases the probability of impact from VS. 

A major drawback of the PSAa is, however, the rather time-consuming calculation, particularly, the Monte Carlo conformational search, which makes PSAa inappropriate for computational screening (e-screening) of large virtual libraries. 

For the generation of targeted libraries, similarity algorithms are useful for computationally screening virtual libraries. Since the number of structures available from such libraries is beyond practical limits, the tools and strategies to be applied for computational screening often differ from the ones used for physically available... 

Wang RX, Wang SM. (2001) How does Consensus Scoring Work for Virtual Library Screening An Ideahzed Computer Experiment. /. Chem. Inf. Comp. Set. 41 1422-1426. 

Key Words Scoring functions virtual ligand screening computational dmg discovery. 

In a more recent virtual screening study, Ballester et al. reported the successful identification of novel inhibitors of ary-lamine N-acetyltransferascs using the USR algorithm (87). A computational screening of 700 million molecular conformers was conducted very efficiently. A small number of the predicted hits were purchased and experimentally tested. An impressive hit rate of 40% has been achieved. The authors also showed the ability of USR to find biologically active compounds with different chemical structures (i.e., scaffold hopping), evidenced by... 

Tanimoto index > 0.9 but may be very different in terms of activity (chemically similar, biologically diverse), while completely different strucmres are known to have the same biological activity (chemically diverse, biologically similar). This intrinsic drawback to the computational screening of virtual libraries should always be considered when interpreting screening results of a computationally designed library, and real data should be used to refine any virtual SAR information based on chemical similarity or dissimilarity. 

LCD is short for liquid crystal display. LCDs are devices that use liquid crystals to create images. Liquid crystal images are being used in watch faces, laptop computer screens, camcorder viewers, virtual reality helmet displays, and televisiou screens. 

The most important use of liquid crystals is in displays because the molecules of a liquid crystal can control the amount, color, and direction of vibration of the light that passes through them. This means that by controlling the arrangement of the molecules, an image in light can be produced and manipulated. Liquid crystal displays, or LCDs, are used in watch faces, laptop computer screens, camcorder viewers, virtual reality helmet displays, and even television screens. 

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